IT202000016255A1 - NEW METALLIC COMPLEXES WITH SALEN-TYPE BINDERS. - Google Patents

Description

NEW METALLIC COMPLEXES WITH SALEN-TYPE BINDERS

DESCRIPTION

The present invention relates to metal complexes with a salen-type binder. Pi? in particular, the present invention relates to a metal complex with a salen-type binder having the specific general formula (I) or (II) reported below.

Said metal complex with a salen-type binder can? be advantageously used as a catalyst in a process for preparing polycarbonates.

The present invention also relates to some salen-type binders, in particular salen-type binders having the specific general formula (XV) or (XVI) reported below.

? It is known that aliphatic polycarbonates are biodegradable polymers mainly used in multilayer compositions for barrier films, as thickeners in the formulation of inks and in the production of various objects. Their interest at an industrial level also derives from the fact that aliphatic polycarbonates can be produced without the use of dangerous reagents such as, for example, phosgene, through a process which involves the copolymerization of an epoxy compound and carbon dioxide (CO2): said process? therefore ?eco-compatible? and has greater prospects for development especially due to the use of carbon dioxide (CO2) which is? considered a readily available and low cost compound.

Since the 1960s many researchers have developed various types of catalytic systems suitable for preparing polycarbonates by means of alternating copolymerization between an epoxy compound and carbon dioxide (CO2).

For example, Inoue S. et al., in ?Journal of Polymer Science Part C: Polymer Letters? (1969), Vol. 7, Issue 4, p. 287-292 , describe the use of an insufficiently characterized heterogeneous catalytic system obtained by partial hydrolysis of diethylzinc (ZnEt2) in the copolymerization of an epoxy compound and carbon dioxide (CO2). However, the catalyst so? obtained has levels of activity? very low, requiring a number of days to produce quantity? significant of polycarbonate.

Aida T. et al., in ?Journal of the American Chemical Society? (1983), Vol.

105, p. 1304-1309, describe the use of aluminum porphyrins having the purpose of activating carbon dioxide (CO2) which is subsequently reacted with an epoxy compound. Furthermore, in this case, the activity? catalytic ? insufficient (< 0.3 turnover/hour).

Darensbourg D.J. et al., in ?Macromolecules? (1995), Vol. 28, p. 7577-7579, describe the use of some phenoxides hindered by zinc (II) in the copolymerization of an epoxy compound and carbon dioxide (CO2), obtaining activity? catalytic up to 2.4 turnover/hour.

Over the years some researchers have proposed the use of catalytic systems based on transition metals and, in particular, the use of chromium(III) or cobalt(III) complexes.

For example, Holmes A.B. et al., in ?Macromolecules? (2000), Vol. 33(2), p. 303-308, describe the use of particular chromium (III) porphyrins in the copolymerization of an epoxy compound and carbon dioxide (CO2). In particular, they describe the production of polycarbonates, in particular poly(cyclohexane carbonate) with considerable yields varying around 50% - 70% and having not very high molecular weights [i.e., having a number average molecular weight (Mn) which varies from 1500 to 3900].

Chen X. et al., in ?Polymer? (2009), Vol. 50, p. 441-446, disclose the use of a series of chromium(III) halide complexes with Schiff base N,N?-bis(salicylidene)-1,2-phenyldiamine (e.g., [Cr(Salen)Cl]) to produce carbonated polypropylene, with not very high yields (< 50%) and selectivity? unsatisfactory towards the formation of polypropylene oxide and/or cyclic dicarbonate, but with interesting molecular weights (number average molecular weight Mn up to 25,000). Similar results were obtained by Lu X. et al., in ?Science Chinese Chemistry? (2010), Vol. 53, p. 1646-1652, which describe the use of complexes based on Co(Salen)Cl in order to produce polypropylene carbonate with yields around 50% and variable molecular weights (number average molecular weights Mn ranging from 6500 to 30000).

Pescarmona P.P. et al., in ?Journal of Applied Polymer Science? (2014), DOI: 10.1002/APP.41141, effectively describe all the aspects inherent in the reaction between epoxides and carbon dioxide (CO2) reporting the chemical/physical characterization of the polymers obtained and their potential field of application.

From what has been described above, the importance of the role of the catalytic system in the production of polycarbonate? therefore clear for the purpose of having high performance in terms of activity?, selectivity?, as well as? in the determination of the properties? ends of the polycarbonate obtained. One of the catalytic systems pi? studied involves the use of transition metal complexes with organic ligands such as, for example, salen-like ligands, as shown in several scientific publications including, for example, Childers M.I., et al., ?Chemical Review? (2014), Vol. 114, p. 8129-8152 and Luo M. et al., in ?Polymer? (2016), Vol. 82, p.

406-431.

Conductive metallopolymers derived from salen-type ligands with thiophene-based substituents are already? been reported in the literature, as well as? other salen-type ligands with substituents based on thiophene groups. The synthesis and characterization of said conductive metal polymers and salen-type ligands have been described, for example, by Reddinger J.L., et al., in ?Synthetic Metals? (1997), Vol. 84, p.

225-226; in ?Macromolecules? (1997), Vol. 30, p. 673-675; in ?Chemistry of Materials? (1998), Vol. 10, p. 1236-1243; by Swager T.M. et al., in ?Journal of the American Chemical Society? (1999), Vol. 121, p. 8825-8834; in ?Chemistry of Materials? (2000), Vol. 12, p. 872-874; in ?Chemical Communication? (2005), p. 23-26; by Asatkar A.K., et al., in ?Chemical Communication? (2014), Vol. 50, p. 7036-7039; in ?Polyhedron? (2015), Vol. 96, p. 25-32; by Hong X., et al., in ?Catalysis Science & Technology? (2013), Vol. 3, p.

723-729.

Since, as reported above, the process for obtaining polycarbonate which involves the copolymerization of an epoxy compound and carbon dioxide (CO2) is ? ?eco-friendly? and of interest especially because of the use of carbon dioxide (CO2) that ? considered a readily available and low-cost component, the study of new metal complexes with a salen-type binder that can be advantageously used in a process for obtaining polycarbonate which involves the copolymerization of an epoxy compound and carbon dioxide (CO2) ? still of great interest.

Is the Applicant yes? therefore set the goal of solving the problem of finding new metal complexes with salen-type ligands.

The Applicant has now found that metal complexes can be used with salen-type ligands having the specific general formula (I) or (II) reported below which can be advantageously used in a process for the preparation of polycarbonates.

Therefore, an object of the present invention is a metal complex with salen-type ligand having general formula (I) or (II):

in which:

- R1 and R2, identical or different, represent a hydrogen atom; or are selected from C1-C20 linear or branched alkyl groups, saturated or unsaturated, preferably C1-C12, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups;

- or R1, identical or different, represent a monovalent organic radical having the general formula (III):

in which:

- R3, R4 and R5, identical or different, represent a hydrogen atom; or are selected from C1-C20 linear or branched alkyl groups, saturated or unsaturated, preferably C1-C12, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups;

- r, s and t, identical or different, are integers ranging from 0 to 5, preferably ranging from 0 to 2, provided that r s t varies from 1 to 5, preferably ranging from 1 to 3;

- or R1 and R2 in the general formula (I), can be connected together to form, together with the other atoms to which they are connected, a saturated or unsaturated cycle or bicycle, which can? optionally being substituted with saturated or unsaturated linear or branched C1-C20 alkyl groups, optionally including heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups;

- Z represents a divalent organic radical having the general formula (IV), (V), (VI), (VII), (VIII), (IX), (X), (XI) or (XII):

in which:

- R6 represents a hydrogen atom; or ? selected from linear or branched, saturated or unsaturated, C1-C20 alkyl groups, preferably C1-C12, optionally containing heteroatoms;

- R7 represents a halogen atom such as, for example, fluorine, chlorine, bromine or iodine, preferably fluorine; either a cyano group, or a nitro group; or ? selected among linear or branched C1-C20 perfluoroalkyl groups, preferably saturated ? a trifluoromethyl group;

- R8, identical or different, represent a hydrogen atom; or represent a halogen atom such as, for example, fluorine, chlorine, bromine or iodine, preferably fluorine; either a cyano group, or a nitro group; or are selected from saturated, linear or branched C1-C20 perfluoroalkyl groups, preferably a trifluoromethyl group, saturated or unsaturated, linear or branched C1-C20 alkyl groups, preferably C1-C12, optionally containing heteroatoms, optionally substituted aryl groups, heteroaryl groups optionally substituted, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups;

- o Z represents a divalent organic radical having general formula (XIII) or (XIV):

in which:

- R9, R10, R11, R12, R13 and R14, identical or different, represent a hydrogen atom; or are selected from C1-C20 linear or branched alkyl groups, saturated or unsaturated, preferably C1-C12, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups;

- either R9 and R10, or R9 and R12 in general formula (XIII), or R9 and R13, or R9 and R14 in general formula (XIV), can be connected together to form, together with the other atoms to which they are connected, a cycle saturated or unsaturated, which can? optionally be substituted with linear or branched C1-C20 alkyl groups, saturated or unsaturated, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups, trialkyl- or triaryl-silyl groups, dialkyl- or diarylamine, dialkyl- or diaryl phosphine groups, C1-C20 linear or branched alkoxy groups, saturated or unsaturated, preferably C2-C10, optionally substituted aryloxy groups, optionally substituted thioalkoxy or thioaryloxy groups, cyano groups, said cyclo optionally containing heteroatoms such as, for example, oxygen, sulfur, nitrogen, silicon, phosphorus, selenium, preferably oxygen, nitrogen; provided that when Z represents a divalent organic radical having general formula (XIII) or (XIV), R1 represents a monovalent organic radical having general formula (III) or R1 and R2, may be linked together to form, together with the other atoms a which are connected, a cycle or bicycle saturated or unsaturated, which can? be optionally replaced with linear or branched C1-C20 alkyl groups, saturated or unsaturated, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups;

- Z? represents a divalent organic radical having general formula (XIII) or (XIV) given above;

- Y represents an oxygen atom, or a sulfur atom, or a selenium atom, or a tellurium atom, preferably an oxygen atom or a sulfur atom; or represents an imido group -N-R15, wherein R15 represents a hydrogen atom; or ? selected from C1-C20 linear or branched alkyl groups, saturated or unsaturated, preferably C1-C12, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted cycloalkyl groups;

- X represents a halogen anion such as, for example, a fluoride anion, a chloride anion, a bromide anion, an iodide anion, preferably a chloride anion, a bromide anion; or ? selected from inorganic anions such as, for example, azide anion, hydroxide anion, amide anion, perchlorate anion, chlorate anion, sulfate anion, phosphate anion, nitrate anion, preferably an azide anion; or ? selected from organic anions such as, for example, carboxylate anion having general formula -OCOR16, alcoholate anion having general formula -OR16, thioalcoholate anion having general formula -SR16, alkyl amide anion having general formula -NHR16, dialkyl-amide anion having general formula -N (R16)2, where R16 ? selected from C1-C20 linear or branched alkyl groups, saturated or unsaturated, preferably C1-C12, optionally containing heteroatoms, or ? selected from optionally substituted aryl groups or optionally substituted cycloalkyl groups;

- M represents a metal atom selected from chromium, manganese, iron, cobalt, aluminium, preferably chromium, cobalt.

For the purposes of this description and the following claims, definitions of numerical ranges always include extremes unless otherwise specified.

For the purposes of the present description and the following claims, the term ?comprising? also includes the terms ?consisting essentially of? or ?which consists of?.

For the purposes of the present description and the following claims, the term ?C1-C20 alkyl groups? means alkyl groups having from 1 to 20 carbon atoms, linear or branched, saturated or unsaturated. Specific examples of C1-C20 alkyl groups are: methyl, ethyl, n-propyl, isopropyl, n-butyl, iso-butyl, tert-butyl, pentyl, hexyl, heptyl, octyl, 2-ethyl, 2-ethylhexyl, 2-butenyl, 2-pentenyl, 2-ethyl-3-hexenyl, 3-octyl, 1-methyl-4-hexenyl, 2-butyl-3-hexenyl.

For purposes of the present description and the following claims, the term ?C1-C20 alkyl groups optionally containing heteroatoms? means alkyl groups having from 1 to 20 carbon atoms, linear or branched, saturated or unsaturated, in which at least one of the hydrogen atoms ? replaced with a heteroatom selected from: halogens such as, for example, fluorine, chlorine, bromine, preferably fluorine; nitrogen; sulfur; oxygen. Specific examples of C1-C20 alkyl groups optionally containing heteroatoms are: fluoromethyl, difluoromethyl, trifluoromethyl, trichloromethyl, 2,2,2-trifluoroethyl, 2,2,2-trichloroethyl, 2,2,3,3-tetrafluoropropyl, 2,2 ,3,3,3-pentafluoropropyl, perfluoropentyl, perfluorooctyl, perfluorodecyl, ethyl-2-methoxy, propyl-3-ethoxy, butyl-2-thiomethoxy, hexyl-4-amino, hexyl-3-N,N'-dimethylamino, methyl-N,N'-dioctylamino, 2-methyl-hexyl-4-amino.

For the purposes of the present description and of the following claims, the term ?aryl groups? means aromatic carbocyclic groups containing 6 to 60 carbon atoms. Said aryl groups can optionally be replaced with one or more? groups, identical or different, selected from: halogen atoms such as, for example, fluorine, chlorine, bromine, preferably fluorine; hydroxyl groups; C1-C12 alkyl groups; C1-C12 alkoxy groups; C1-C12 thioalkoxy groups; C3-C24 trialkylsilyl groups; polyethyleneoxy groups; cyan groups; amine groups; C1-C12 mono- or di-alkylamine groups; nitro groups. Specific examples of aryl groups are: phenyl, methylphenyl, trimethylphenyl, methoxyphenyl, hydroxyphenyl, phenyloxyphenyl, fluorophenyl, pentafluorophenyl, chlorophenyl, bromophenyl, nitrophenyl, dimethylaminophenyl, naphthyl, phenylnaphthyl, phenanthrene, anthracene.

For the purposes of the present description and of the following claims, the term ?heteroaryl groups? means penta- or hexa-atomic heterocyclic aromatic groups, also benzocondensate or heterobicyclic, containing from 4 to 60 carbon atoms and from 1 to 4 heteroatoms selected from nitrogen, oxygen, sulphur, silicon, selenium, phosphorus. Said heteroaryl groups can optionally be replaced with one or more? groups, identical or different, selected from: halogen atoms such as, for example, fluorine, chlorine, bromine, preferably fluorine; hydroxyl groups; C1-C12 alkyl groups; C1-C12 alkoxy groups; C1-C12 thioalkoxy groups; C3-C24 trialkylsilyl groups; polyethyleneoxy groups; cyan groups; amine groups; C1-C12 mono- or di-alkylamine groups; nitro groups. Specific examples of heteroaryl groups are: pyridine, methylpyridine, methoxymethylpyridine, phenylmethylpyridine, fluoromethylpyridine, pyrimidine, pyridazine, pyrazine, triazine, tetrazine, quinoline, quinoxaline, quinazoline, furan, thiophene, hexylthiophene, bromothiophene, dibromothiophene, pyrrole, oxazole, thiazole, isoxazole , isothiazole, oxadiazole, thiadiazole, pyrazole, imidazole, triazole, tetrazole, indole, benzofuran, benzothiophene, benzoxazole, benzothiazole, benzoxadiazole, benzothiadiazole, benzopyrazole, benzimidazole, benzotriazole, triazole pyridine, triazole pyrimidine, coumarin. Said optionally substituted heteroaryl groups may optionally be in the cationic form. Specific examples of heteroaryl groups in the cationic form are: pyridinium, N-methyl-pyridinium, N-butylpyridinium, N-phenyl-pyridinium, N-methyl-4-methoxy-pyridinium, N-ethyl -2-fluoropyridinium, pyrilium, trimethyl- pyrylium, 2,6-di-tert-butyl-pyrylium, 4-phenyl-2,6-di-iso-propylpyrylium, 2,6-di-tert-butyl-thiopyrylium, 2,6-diphenyl-thiopyrylium.

For the purposes of the present description and the following claims, the term ?cycloalkyl groups? means cycloalkyl groups having from 3 to 60 carbon atoms. Said cycloalkyl groups can optionally be replaced with one or more? groups, identical or different, selected from: halogen atoms such as, for example, fluorine, chlorine, bromine, preferably fluorine; hydroxyl groups; C1-C12 alkyl groups; C1-C12 alkoxy groups; C1-C12 thioalkoxy groups; C3-C24 trialkylsilyl groups; polyethyleneoxy groups; cyan groups; amine groups; C1-C12 mono- or di-alkylamine groups; nitro groups. Specific examples of cycloalkyl groups are: cyclopropyl, 2,2-difluorocyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, methylcyclohexyl, methoxycyclohexyl, fluorocyclohexyl, phenylcyclohexyl, decalin, abetyl.

For the purposes of the present description and of the following claims, the term ?heterocyclic groups? indicates rings having from 3 to 12 atoms, saturated or unsaturated, containing at least one heteroatom selected from nitrogen, oxygen, sulphur, silicon, selenium, phosphorus, optionally condensed with other aromatic or non-aromatic rings. Said heteroaryl groups can optionally be replaced with one or more? groups, identical or different, selected from: halogen atoms such as, for example, fluorine, chlorine, bromine, preferably fluorine; hydroxyl groups; C1-C12 alkyl groups; C1-C12 alkoxy groups; C1-C12 thioalkoxy groups; C3-C24 trialkylsilyl groups; polyethyleneoxy groups; cyan groups; amine groups; C1-C12 mono- or di-alkylamine groups; nitro groups. Specific examples of heterocyclic groups are: pyrrolidine, methoxypyrrolidine, piperidine, fluoropiperidine, methylpiperidine, dihydropyridine, piperazine, morpholine, thiazine, indoline, phenylindoline, 2-ketoazetidine, diketopiperazine, tetrahydrofuran, tetrahydrothiophene. Said optionally substituted heterocyclic groups can optionally be in the cationic form. Specific examples of heterocyclic groups in cationic form are: N-butylpyrrolidinium, N,N'-dimethylpyrrolidinium, N,N'-diethylpyrrolidinium, N-ethyl,N'-phenylpyrrolidinium, N,N'-dimethylpiperidinium, N-methyl,N' -butylpiperidinium, N-methyl,N'-phenylpiperidinium.

For the purposes of the present description and of the following claims, the term ?cycle? or ?bicycle? means a system containing from 1 to 16 carbon atoms, optionally containing heteroatoms selected from nitrogen, oxygen, sulphur, silicon, selenium, phosphorus. Specific examples of cycle or bicycle? they are: toluene, benzonitrile, cycloheptatriene, cyclooctadiene, pyridine, piperidine, tetrahydrofuran, thiadiazole, pyrrole, thiophene, selenophene, tert-butylpyridine, 1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H, 5H-pyrido[3,2,1-ij]quinolone.

For the purpose of the present description and the following claims, the term ?trialkyl- or triaryl-silyl groups? means groups comprising a silicon atom to which are bonded three C1-C12 alkyl groups, or three C6-C24 aryl groups, or a combination thereof. Specific examples of trialkyl- or triaryl-silyl groups are: trimethylsilane, triethylsilane, triesylsilane, tridodecylsilane, dimethyl-(dodecyl)silane, triphenylsilane, methyl(diphenyl)silane, dimethyl(naphthyl)-silane.

For the purpose of the present description and the following claims, the term ?dialkyl- or diaryl-amine groups? means groups comprising a nitrogen atom to which are bonded two C1-C12 alkyl groups, or two C6-C24 aryl groups, or a combination thereof. Specific examples of dialkyl- or diarylamine groups are: dimethylamine, diethylamine, dibutylamine, di-iso-butylamine, diphenylamine, methylphenylamine, dibenzylamine, ditolylamine, dinaphthylamine

For the purpose of the present description and the following claims, the term ?dialkyl- or diaryl-phosphine groups? means groups comprising a phosphorus atom to which are bonded two C1-C12 alkyl groups, or two C6-C24 aryl groups, or a combination thereof. Specific examples of dialkyl- or diaryl-phosphine groups are: dimethylphosphine, diethylphosphine, dibutylphosphine, diphenylphosphine, methylphenylphosphine, dinaphthylphosphine.

For the purposes of the present description and the following claims, the term ?C1-C20 alkoxy groups? denotes groups comprising an oxygen atom to which ? connected a linear or branched C1-C20 alkyl group. Specific examples of C1-C20 alkoxy groups are: methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, iso-butoxy, tert-butoxy, pentoxy, hexyloxy, heptyloxy, octyloxy, nonyloxy, decyloxy, dodecyloxy.

For the purposes of the present description and of the following claims, the term ?aryloxy groups? means groups comprising an oxygen atom to which ? linked a linear or branched C6-C24 aryl group. Said aryloxy groups can optionally be replaced with one or more? groups, identical or different, selected from: halogen atoms such as, for example, fluorine, chlorine, bromine, preferably fluorine; hydroxyl groups; C1-C12 alkyl groups; C1-C12 alkoxy groups; C1-C12 thioalkoxy groups; C3-C24 trialkylsilyl groups; cyan groups; amine groups; C1-C12 mono- or di-alkylamine groups; nitro groups. Specific examples of aryloxy groups are: phenoxy, para-methylphenoxy, parafluorophenoxy, ortho-butylphenoxy, naphthyloxy, anthracenoxy.

For the purposes of the present description and the following claims, the term ?thioalkoxy or thioaryloxy groups? means groups comprising a sulfur atom to which ? bound a C1-C12 alkoxy group or a C6-C24 aryloxy group. Said thioalkoxy or thioaryloxy groups can optionally be replaced with one or more? groups, identical or different, selected from: halogen atoms such as, for example, fluorine, chlorine, bromine, preferably fluorine; hydroxyl groups; C1-C12 alkyl groups; C1-C12 alkoxy groups; C1-C12 thioalkoxy groups; C3-C24 trialkylsilyl groups; cyan groups; amine groups; C1-C12 mono- or dialkylamine groups; nitro groups. Specific examples of thioalkoxy or thioaryloxy groups are: thiomethoxy, thioethoxy, thiopropoxy, thiobutoxy, thio-iso-butoxy, 2-ethylthiohexyl, thiophenoxy, para-methylthiophenoxy, para-fluorothiophenoxy, ortho-butylthiophenyl, anthracenylthioxy.

Specific examples of metal complexes with a salen-type ligand having general formula (I) or (II) are shown in table 1.

Table 1

The metal complexes with salen-type ligand having general formula (I) or (II) can be prepared according to processes known in the art as described, for example, by Darensbourg D.J. et al., in ?Inorganic Chemistry? (2004), Vol.

43(19), p. 6024-6034. Further details relating to the preparation of said metal complexes with a salen-type binder having general formula (I) or (II) can be found in the following examples.

As reported above, the present invention also relates to some salen-type binders.

Consequently, a further objective of the present invention ? a salen-type binder having general formula (XV) or (XVI):

in which:

- R17, identical or different, represent a hydrogen atom; or they are selected from linear or branched, saturated or unsaturated C1-C6 alkyl groups, preferably C1-C2; more preferably, they are identical and represent a hydrogen atom or a methyl group;

- R1 and R2, identical or different, represent a hydrogen atom; or are selected from C1-C20 linear or branched alkyl groups, saturated or unsaturated, preferably C1-C12, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups;

- or R1, identical or different, represent a monovalent organic radical having the general formula (III):

in which:

- R3, R4 and R5, identical or different, represent a hydrogen atom; or are selected from C1-C20 linear or branched alkyl groups, saturated or unsaturated, preferably C1-C12, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups;

- r, s and t, identical or different, are integers ranging from 0 to 5, preferably ranging from 0 to 2, provided that r s t varies from 1 to 5, preferably ranging from 1 to 3;

- or R1 and R2 in the general formula (I), can be connected together to form, together with the other atoms to which they are connected, a saturated or unsaturated cycle or bicycle, which can? optionally being substituted with saturated or unsaturated linear or branched C1-C20 alkyl groups, optionally including heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups;

- Z represents a divalent organic radical having the general formula (IV), (V), (VI), (VII), (VIII), (IX), (X), (XI) or (XII):

in which:

- R6 represents a hydrogen atom; or ? selected from linear or branched, saturated or unsaturated, C1-C20 alkyl groups, preferably C1-C12, optionally containing heteroatoms;

- R7 represents a halogen atom such as, for example, fluorine, chlorine, bromine or iodine, preferably fluorine; either a cyano group, or a nitro group; or ? selected among linear or branched C1-C20 perfluoroalkyl groups, preferably saturated ? a trifluoromethyl group;

- R8, identical or different, represent a hydrogen atom; or represent a halogen atom such as, for example, fluorine, chlorine, bromine or iodine, preferably fluorine; either a cyano group, or a nitro group; or are selected from saturated, linear or branched C1-C20 perfluoroalkyl groups, preferably a trifluoromethyl group, saturated or unsaturated, linear or branched C1-C20 alkyl groups, preferably C1-C12, optionally containing heteroatoms, optionally substituted aryl groups, heteroaryl groups optionally substituted, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups;

- o Z represents a divalent organic radical having general formula (XIII) or (XIV):

in which:

- R9, R10, R11, R12, R13 and R14, identical or different, represent a hydrogen atom; or are selected from C1-C20 linear or branched alkyl groups, saturated or unsaturated, preferably C1-C12, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups;

- either R9 and R10, or R9 and R12 in general formula (XIII), or R9 and R13, or R9 and R14 in general formula (XIV), can be connected together to form, together with the other atoms to which they are connected, a cycle saturated or unsaturated, which can? optionally be substituted with linear or branched C1-C20 alkyl groups, saturated or unsaturated, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups, trialkyl- or triaryl-silyl groups, dialkyl- or diarylamine, dialkyl- or diaryl phosphine groups, C1-C20 linear or branched alkoxy groups, saturated or unsaturated, preferably C2-C10, optionally substituted aryloxy groups, optionally substituted thioalkoxy or thioaryloxy groups, cyano groups, said cyclo optionally containing heteroatoms such as, for example, oxygen, sulfur, nitrogen, silicon, phosphorus, selenium, preferably oxygen, nitrogen; provided that when Z represents a divalent organic radical having general formula (XIII) or (XIV), R1 represents a monovalent organic radical having general formula (III) or R1 and R2, may be linked together to form, together with the other atoms a which are connected, a cycle or bicycle saturated or unsaturated, which can? be optionally replaced with linear or branched C1-C20 alkyl groups, saturated or unsaturated, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups;

- Z? represents a divalent organic radical having general formula (XIII) or (XIV) given above;

- Y represents an oxygen atom, or a sulfur atom, or a selenium atom, or a tellurium atom, preferably an oxygen atom or a sulfur atom; or represents an imido group -N-R15, wherein R15 represents a hydrogen atom; or ? selected from C1-C20 linear or branched alkyl groups, saturated or unsaturated, preferably C1-C12, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted cycloalkyl groups;

- X represents a halogen anion such as, for example, a fluoride anion, a chloride anion, a bromide anion, an iodide anion, preferably a chloride anion, a bromide anion; or ? selected from inorganic anions such as, for example, azide anion, hydroxide anion, amide anion, perchlorate anion, chlorate anion, sulfate anion, phosphate anion, nitrate anion, preferably an azide anion; or ? selected from organic anions such as, for example, carboxylate anion having general formula -OCOR16, alcoholate anion having general formula -OR16, thioalcoholate anion having general formula -SR16, alkyl amide anion having general formula -NHR16, dialkyl-amide anion having general formula -N (R16)2, where R16 ? selected from C1-C20 linear or branched alkyl groups, saturated or unsaturated, preferably C1-C12, optionally containing heteroatoms, or ? selected from optionally substituted aryl groups or optionally substituted cycloalkyl groups;

- M represents a metal atom selected from chromium, manganese, iron, cobalt, aluminium, preferably chromium, cobalt.

Salen-type binders having general formula (XV) or (XVI) can be prepared according to processes known in the art as described, for example, by Darensbourg D.J. et al., in ?Inorganic Chemistry? (2004), Vol. 43(19), p.

6024-6034, listed above. Further details relating to the preparation of said salen-type binders having general formula (XV) or (XVI) can be found in the following examples.

As reported above, said metal complex with salen-type ligand can? be advantageously used in a process for preparing polycarbonates.

Consequently, a further objective of the present invention ? the use of a metal complex with a salen-type binder having general formula (I) or (II) as a catalyst in a process for preparing polycarbonates.

In order to better understand the present invention and to put it into practice, some illustrative and non-limiting examples are given below.

Reagents and materials

The reagents and materials used in the following examples, as well as their manufacturers, have been listed below:

- methanol (Aldrich): used as such;

- copper(II) oxide (powder; 99.99% purity) (Aldrich): used as such; - sodium iodide (purity ? 99.5%) (Aldrich): used as such;

- 3,4-dibromothiophene (99% purity) (Aldrich): used as such;

- dioxane (Aldrich): used as such;

- 1 M hydrochloric acid (HCl) solution (Aldrich): used as such;

- petroleum ether (Aldrich): used as such;

- magnesium sulphate (MgSO4) (purity ? 99.99%) (Aldrich): used as such;

- dichloromethane (CH2Cl2) (Aldrich): used as such;

- 3-methylthiophen-2-yl-2-boronic acid (Alfa Aesar): used as such;

- sodium carbonate (Na2CO3) (purity ? 99.5%) (Aldrich): used as such; - tetrakis(triphenylphosphine)palladium(0) [(Pd(PPh3)4] (Aldrich): used as such - ethyl acetate (purity ?99.5%) (Aldrich): used as such;

- sodium chloride (NaCl) (Aldrich): used as such;

- phosphorus(V) oxychloride (POCl3) (purity 99.999%) (Aldrich): used as such;

- dimethylformamide (DMF) (anhydrous; purity 99.8%) (Aldrich): used as such;

- 1,2-dichloroethane (Aldrich): used as such;

- sodium acetate (NaOAc) (~3 M in H2O) (Aldrich): used as such;

- (1R, 2R)-cyclohexane-1,2-diamine (purity 98%) (Aldrich): used as such;

- acetic acid (glacial; purity ? 99.85%) (Aldrich): used as such; - thiophene (purity ? 99%) (Aldrich): used as such;

- n-butyl lithium (1.6 M solution in hexanes) (Aldrich): used as such;

- 2-ethylhexylbromide (Aldrich): used as such;

- tetrahydrofuran (THF) (anhydrous; purity ? 99.9%): used as such;

- n-butyl lithium (2.5 M solution in hexanes) (Aldrich): used as such; - tri-butyltin chloride (purity 96%) (Aldrich): use as such;

- sodium fluoride (NaF) (0.5 M aqueous solution) (Aldrich): used as such;

- celite (Celite<? >S) (Aldrich): used as such;

- 3-bromo-2-hydroxybenzaldehyde (97% purity) (Aldrich): used as such; - toluene (purity ? 99.5%) (Aldrich): degassed and stored in a nitrogen atmosphere before use;

- bromine (Br2) (purity ? 99.5%) (Aldrich): used as such;

- 3,5-tert-butyl-2-hydroxybenzaldehyde (purity 98%) (Aldrich): used as such;

- sodium sulfite (NaHSO3) (Aldrich): used as such;

- sodium bicarbonate (purity ? 99.7%) (Aldrich): used as such;

- 1,2,5-oxadiazol-3,4-diamine (Aldrich): used as such;

- 3,5-di-tert-butyl-2-hydroxybenzaldehyde (99% purity) (Aldrich): used as such;

- naphthalene-2,3-diamine (purity ? 95%) (Aldrich): used as such;

- aluminum trichloride (AlCl3) (purity 98%) (Aldrich): used as such; - dichloromethane (CH2Cl2) (anhydrous; purity ? 99.8%) (Aldrich): used as such;

- tert-butyl chloride (99% purity) (Aldrich): used as such;

- N-bromosuccinimide (99% purity) (Aldrich): used as such;

- 2-bromothiophene (98% purity) (Aldrich): used as such;

- magnesium shavings (purity 98%) (Aldrich): used as such;

- diethyl ether (anhydrous; purity ? 99%) (Aldrich): used as such;

- [1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium(II) complex with dichloromethane [Pd(dppf)Cl2<.>CH2Cl2] (Aldrich): used as such;

- 8-hydroxy-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-pyrido[3,2,1-ij]quinoline-9-carbaldehyde (Aldrich): used as such;

- chromium(II) chloride (CrCl2) (purity 95%) (Aldrich): used as such; - ammonium chloride (NH4Cl) (purity ? 99.5%) (Aldrich): used as such;

- petroleum ether (Aldrich): used as such;

- dicalite (Thermofischer Scientific): used as such;

- cobalt acetate ([Co(AAc)2] (purity 99.995%) (Aldrich): used as such;

- deuterated methylene chloride (CD2Cl2) (Aldrich): used as such;

- 3,4-diaminobenzonitrile (97% purity) (Aldrich): used as such;

- 4-fluoro-1,2-phenylenediamine (97% purity) (Aldrich): used as such; - 9,10-diaminophenanthrene (97% purity) (Aldrich): used as such;

- acetone (Aldrich): used as such;

- heptane (Aldrich): used as such.

The following analysis and characterization methodologies are used.

NMR spectra

NMR spectra were recorded with a Bruker AVANCE III 300 spectrometer (<1>H, 300 MHz and <13>C, 76 MHz). For this purpose, about 5 mg of the sample to be tested was dissolved in about 0.4 ml of deuterated solvent directly in the glass cuvette used for the measurement. The chemical shifts are reported in ppm with respect to TMS (<1>H and <13>C) and the coupling constants J in Hz. Non-deuterated solvent residues were used as internal standard for <1>H NMR spectra: a singlet at 7.26 ppm for CHCl3 and a quintet at 2.50 ppm for DMSO-d5. For <13>C NMR spectra, a triplet at 77.16 ppm for CDCl3 or a septet at 39.52 ppm for DMSO-d6 were used as the internal standard. Matrix-assisted laser desorption/ionization (MALDI)

Matrix assisted laser desorption/ionization ? was performed on MALDI-TOF MS BIFLEX III Bruker Daltonics spectrometer using dithranol or DCTB (2-[(2E)-3-(4-tert-butylphenyl)-2-methylprop-2-enylidene]malononitrile) as matrix.

High Resolution Mass Spectrometry (HRMS)

High Resolution Mass Spectrometry (HRMS) ? was performed with a JEOL JMS-700 B/E spectrometer by electron impact (EI), positive chemical ionization (CI<+>) or fast atomic bombardment (FAB).

Purification

The purification of compounds ? was performed using standard column chromatography using analytical grade solvents and Aldrich silica gel (engineer grade, 60 E pore size, 230-400 mesh particle size). ALUGRAM flexible plates? Xtra SIL G UV254 from MACHEREY-NAGEL were used for TLC. The compounds were detected by UV irradiation (Bioblock Scientific), unless otherwise indicated.

In some cases, the compounds were purified by recycle preparative size-exclusion HPLC (Japan Analytical Industry) using chloroform as a solvent.

EXAMPLE 1

Synthesis of N,N'-((1R,2R)-cyclohexane-1,2-diyl)bis(1-(4'-methoxy-3-methyl-[2,3'-bitiophen]-5'-yl) metanimine) (XVa)

Dioxane = dioxane

Synthesis of 3-bromo-4-methoxythiophene (2)

In a 250 ml double-necked flask, to a solution of sodium (1.27 g, 55.24 mmol) in methanol (12 ml), was added in the order: copper(II) oxide powder (2 .09 g, 26.27 mmol), sodium iodide (240 mg, 1.60 mmol), and a solution of 3,4-dibromothiophene (1) (4.6 mL, 41.16 mmol) in dioxane (20 mL ): the mixture obtained ? was vigorously stirred and refluxed for 60 hours. Subsequently, the solvent ? been removed through a rotary evaporator and the residue obtained? was added to an aqueous solution of hydrochloric acid (HCl) (1 M) and extracted with light petroleum (3 x 30 ml). The organic phases obtained were combined, dried over magnesium sulphate (MgSO4), filtered and, subsequently, the remaining solvent ? been removed, vacuum packed. The residue obtained? was purified by silica gel chromatography (eluent: petroleum ether) to obtain a colorless oil (2.9 g, yield: 37%) corresponding to 3-bromo-4-methoxythiophene (2).

<1>H NMR (300 MHz, CDCl3) ? 7.20 (d, 1H, J= 3.4Hz), 6.24 (d, 1H, J= 3.4Hz), 3.88 (s, 3H).

Synthesis of 4'-methoxy-3-methyl-2,3-bithiophene (4)

In a 250 ml double-necked flask, to a stirred suspension of 3-bromo-4-methoxythiophene (2) obtained as described above (3 g, 15.54 mmol) and (3-methylthiophen-2-yl)boronic acid (3) (3.31 g, 23.31 mmol) in dioxane (120 mL) ? was added sodium carbonate (Na2CO3) (14.82 g, 139.85 mmol) dissolved in distilled water (50 ml): the mixture obtained? was degassed under argon flow for 30 minutes. Subsequently ? tetrakis(triphenylphosphine)palladium(0) [(Pd(PPh3)4] (1.87 g, 1.55 mmol) was added and the mixture was kept at 120°C overnight. obtained was cooled to room temperature (25°C) and extracted with ethyl acetate (3 x 50 ml).The organic phases obtained were combined, washed with a saturated aqueous solution of sodium chloride (NaCl) (3 x 100 ml ), dried over magnesium sulphate (MgSO4), filtered and subsequently the remaining solvent was removed under vacuum.The residue obtained was purified by silica gel chromatography (eluent: petroleum ether/dichloromethane, 1/1 v/ v) obtaining a colorless oil (3.2 g, yield: 98%) corresponding to 4?-methoxy-3-methyl-2,3'-bithiophene (4).

<1>H NMR (300 MHz, CDCl3) ? 7.23-7.17 (m, 2H), 6.91 (d, 1H, J= 5Hz), 6.32 (d, 1H, J= 3.4Hz), 3.86 (s, 3H), 2.26 (s, 3H).

Synthesis of 4'-methoxy-3-methyl-[2,3'-bithiophene]-5'-carbaldehyde (5)

In a 250 ml two-necked flask, under argon, ? phosphorus (V) oxychloride (POCl3) (1 ml, d = 1.65 g/l, 10.46 mmol) was added to a solution of 4'-methoxy-3-methyl-2,3'-bithiophene (4 ) obtained as above (2 g, 9.51 mmol) and anhydrous dimethylformamide (DMF) (1.1 ml, 14.26 mmol) in 1,2-dichloroethane (120 ml), at 0?C. The mixture obtained? stirred for 15 hours at room temperature (25°C), cooled again to 0°C and, subsequently, a saturated aqueous solution of sodium acetate (NaOAc) (10 ml) ? been added to the same: the mixture obtained ? was further stirred, for 4 hours, at room temperature (25°C). Subsequently, the mixture obtained ? was extracted with dichloromethane (CH2Cl2) (2 x 25 mL). The organic phases obtained were combined, washed with water (40 ml), dried over magnesium sulphate (MgSO4), filtered and, subsequently, the remaining solvent ? been removed, vacuum packed. The residue obtained? was purified by silica gel chromatography (eluent: petroleum ether/dichloromethane, 1/1 v/v) to obtain a colorless oil (963 mg, yield: 40%) corresponding to 4'-methoxy-3-methyl-[2 ,3'-bitiophene]-5'-carbaldehyde (5).

<1>H NMR (300 MHz, CDCl3) ? 10.11 (d, 1H, J= 1.2Hz), 7.58 (d, 1H, J=1.2Hz), 7.28 (d, 1H, J=5.0Hz), 6.93 (d, 1H, J=5.0Hz), 3.87 ( s, 3H), 2.24 (s, 3H).

HRMS (EI) calculated for C11H10O2S2: 238.0122; found: 238.0120.

Synthesis of N,N'-((1R,2R)-cyclohexane-1,2-diyl)bis(1-(4'-methoxy-3-methyl-[2,3'-bitiophen]-5'-yl) metanimine) (XVa)

In a 100 ml double-necked flask, a mixture of 4'-methoxy-3-methyl-[2,3'-bitiophen]-5'-carbaldehyde (5) obtained as above (234 mg, 0.98 mmol ), (1R,2R)-cyclohexane-1,2-diamine (6) (50 mg, 0.44 mmol) and methanol (20 ml) with a few drops of a glacial acetic acid, ? refluxed overnight. Subsequently, the solvent ? been removed, through a rotary evaporator and the residue obtained? was purified by recycle preparative size exclusion HPLC to obtain an orange solid (140 mg, yield: 58%) corresponding to Salen (XVa).

<1>H NMR (300 MHz, CDCl3) ? 8.19 (s, 2H), 7.19 (d, J= 3.4 Hz, 2H), 6.98 (s, 2H), 6.30 (d, J= 3.4 Hz, 2H), 3.84 (s, 6H), 3.34 ? 3.27 (m, 2H), 2.18 (s, 6H), 1.86 ? 1.37 (m, 8H).

HRMS (FAB) calculated for [M+H] C28H31N2O2S4: 555.1190; found: 555.1271.

EXAMPLE 2

Summary of Salen (XVIa)

Synthesis of 2-(2-ethylhexyl)thiophene (7)

A stirred solution of thiophene (2.50 mL, 31.26 mmol) in anhydrous tetrahydrofuran (THF) (50 mL) in a 250 mL double-necked flask, ? been cooled down to 0?C, in an ice bath. During stirring, a solution of n-butyl lithium in hexane (1.6 M solution, 21.49 mL, 34.37 mmol), ? was added drop by drop, over 30 minutes. After another 30 minutes of stirring, at 0?C, ? 2-ethylhexylbromide (5.56 mL, 31.26 mmol) was added rapidly. Subsequently, the mixture obtained ? was heated up to 60°C and maintained at this temperature, under stirring, for 16 hours, subsequently cooled down to room temperature (25°C) and subjected to quenching with water. Next, the blend was extracted with petroleum ether (3 x 50 ml): the obtained organic phases were combined, washed with water (40 ml), dried over magnesium sulphate (MgSO4), filtered and, subsequently, the remaining solvent ? been removed, vacuum packed. The colorless oil obtained? was purified by silica gel chromatography [eluent: petroleum ether] to obtain a clear oil (2.57 g, yield: 42%) corresponding to 2-(2-ethylhexyl)thiophene (7).

<1>H NMR (300 MHz, CDCl3) ? 7.12 (dd, J= 5.1, 1.2 Hz, 1H), 6.92 (dd, J= 5.1, 3.4 Hz, 1H), 6.77 (dd, J= 3.4, 0.9 Hz, 1H), 2.77 (d, J= 6.7 Hz , 2H), 1.63 ? 1.49 (m, 1H), 1.39 ? 1.23 (m, 8H), 0.89 (t, J= 7.4Hz, 6H).

Synthesis of tributyl(5-(2-ethylhexyl)thiophen-2-yl)stannane (8)

A stirred solution of 2-(2-ethylhexyl)thiophene(7) obtained as above (2.57 g, 13.09 mmol) in anhydrous tetrahydrofuran (THF) (40 ml) in a 250 ml double-necked flask, ? been cooled down to 0?C, in an ice bath. During stirring, a solution of n-butyl lithium in hexane (1.6 M solution, 21.49 mL, 34.37 mmol), ? was added drop by drop, over 30 minutes. After another 30 minutes of stirring, at 0?C, ? tributyltin chloride (4.26 mL, 15.71 mmol) was added rapidly. Subsequently, the mixture obtained ? was heated up to 60°C and maintained at this temperature, under stirring, for 16 hours, subsequently cooled down to room temperature (25°C) and subjected to quenching with water. Next, the blend was extracted with ethyl acetate (2 x 50 ml), concentrated under vacuum and subsequently redissolved in ethyl acetate (50 ml). The solution obtained? was washed with a saturated aqueous solution of sodium fluoride (NaF) (100 ml) and stirred for 15 minutes, obtaining a residue which ? was removed by filtration on celite and washed with ethyl acetate (3 x 20 ml). Subsequently, the obtained aqueous phases were combined and extracted with ethyl acetate (3 x 50 ml). The organic phases obtained were combined, washed with a saturated aqueous solution of sodium chloride (NaCl) (2 x 100 ml), dried over magnesium sulphate (MgSO4), filtered and subsequently the remaining solvent ? was removed, in vacuo, to obtain a crude tan oil corresponding to tributyl(5-(2-ethylhexyl)thiophen-2-yl)stannane (8) (6.70 g, 13.80 mmol, yield: 105%) which ? was used without further purification.

Synthesis of 3-(5-(2-ethylhexyl)thiophen-2-yl)-2-hydroxybenzaldehyde (9)

In a 250 ml double-necked flask, to a stirred mixture of tributyl(5-(2-ethylhexyl)thiophen-2-yl)stannane (8) obtained as above (2.17 g, 4.48 mmol) and 3-bromo-2-hydroxybenzaldehyde (750 mg, 3.73 mmol) in degassed toluene (40 ml), ? tetrakis(triphenylphosphine)palladium(0) [(Pd(PPh3)4] (216 mg, 0.186 mmol) was added: the resulting mixture was stirred at 110°C overnight, then cooled down to room temperature ( 25°C) and concentrated under vacuum.The residue obtained was purified by silica gel chromatography (eluent: dimethyl carbonate/petroleum ether, 1/1 v/v) to obtain a yellow oil (0.74 g, yield: 63 %) corresponding to 3-(5-(2ethylhexyl)thiophen-2-yl)-2-hydroxybenzaldehyde (9).

<1>H NMR (300 MHz, CDCl3): ? 11.91 (s, 1H), 9.93 (s, 1H), 7.84 (dd, J= 7.7, 1.5 Hz, 1H), 7.49 (d, J= 3.7 Hz, 1H), 7.46 (dd, J= 7.8, 1.6 Hz , 1H), 7.05 (t, J= 7.7 Hz, 1H), 6.78 (d, J= 3.6 Hz, 1H), 2.78 (d, J= 6.8 Hz, 2H), 1.67 ? 1.56 (m, 1H), 1.42 ? 1.27 (m, 8H), 0.93 ? 0.86 (m, 6H).

<13>C NMR (76 MHz, CDCl3): ? 197.06, 157.91, 145.36, 135.14, 135.09, 132.34, 126.52, 125.76, 123.96, 121.10, 120.03, 41.57, 34.19, 32.54, 29.03, 25.66 , 11.16pm, 2.30pm, 10.99am.

Summary of Salen (XVIa)

In a 100 ml double-necked flask, a mixture of 3-(5-(2-ethylhexyl)thiophen-2-yl)-2-hydroxybenzaldehyde (9) obtained as described above (730 mg, 2.31 mmol) and (1R,2R)-cyclohexane-1,2-diamine (6) (132 mg, 1.15 mmol) in methanol (15 ml), ? been stirred all night. Next, the blend been concentrated under vacuum and the residue obtained ? was purified by recycle preparative size exclusion HPLC to obtain an orange-red oil (0.79 g, yield: 96.3%) corresponding to Salen (XVIa).

<1>H NMR (300 MHz, CDCl3): ? 14.46 (s, 2H), 8.27 (s, 2H), 7.58 (dd, J = 7.7, 1.6 Hz, 2H), 7.39 (d, J = 3.6 Hz, 2H), 7.04 (dd, J = 7.6, 1.6 Hz , 2H), 6.80 (d, J = 7.7 Hz, 2H), 6.75 (d, J = 3.7 Hz, 2H), 3.42 ? 3.30 (m, 2H), 2.77 (d, J = 6.8Hz, 4H), 2.05 ? 1.85 (m, 4H), 1.84 ? 1.68 (m, 2H), 1.68 ? 1.58 (m, 2H), 1.52 ? 1.23 (m, 18H), 0.90 (t, J = 7.4Hz, 12H).

<13>C NMR (76 MHz, CDCl3): ? 165.34, 158.03, 144.53, 136.61, 130.71, 130.48, 125.28, 125.16, 123.03, 118.80, 118.54, 72.35, 41.56, 34.23, 33.19, 32.57 , 29.04, 25.65, 24.35, 23.19, 14.32, 10.99.

MALDI-TOF MS (dithranol): 711.3.

HRMS (FAB): calculated for C44H58N2O2S2 (710.3940); found 710.3942 & 711.4025 (M 1).

EXAMPLE 3

Summary of Salen (XVIb)

Synthesis of 3-bromo-5-(tert-butyl)-2-hydroxybenzaldehyde(11)

In a 250 mL double-necked flask, a mixture of bromide (Br2) (2.29 g, 0.73 mL, 14.31 mmol) in glacial acetic acid (25 mL) ? was added dropwise over a period of 30 minutes to a stirred solution of sodium acetate (NaOAc) (2.30 g, 28.05 mmol) and 5-(tert-butyl)-2-hydroxybenzaldehyde (10) ( 2.50 g, 2.41 mL, 14.03 mmol) in glacial acetic acid (60 ml): the reaction mixture obtained ? was stirred at 50°C for 24 hours. Subsequently, after removal of the solvent under vacuum, water (80 mL) and dichloromethane (CH2Cl2) (65 mL) were added. The aqueous phase obtained? was extracted with dichloromethane (CH2Cl2) (2 ? 30 ml). The organic phases obtained were combined, washed with an aqueous solution of sodium sulphite (NaHSO3) (80 ml, 10% w/v) and with a saturated aqueous solution of sodium bicarbonate (80 ml), dried over magnesium sulphate (MgSO4), filtered and, subsequently, the remaining solvent ? been removed under vacuum. The residue obtained? was purified by recrystallization from petroleum ether to obtain yellow crystals corresponding to 3-bromo-5-(tert-butyl)-2-hydroxybenzaldehyde (11) (3.1 g, yield: 86%).

<1>H NMR (300 MHz, CDCl3): ? 11.41 (s, 1H), 9.85 (s, 1H), 7.81 (d, J= 2.3 Hz, 1H), 7.51 (d, J= 2.4 Hz, 1H), 1.33 (s, 9H).

Synthesis of 5-(tert-butyl)-3-(5-(2-ethylhexyl)thiophen-2-yl)-2-hydroxy-benzaldehyde (12) In a 250 ml double-necked flask, to a stirred mixture of tri-butyl(5-(2-ethylhexyl)thiophen-2-yl)stannane (8) obtained as reported in example 2 (2.27 g, 4.67 mmol) and 3-bromo-5-(tert-butyl) -2-Hydroxybenzaldehyde (11) obtained as reported above (800 mg, 3.11 mmol) in degassed toluene (40 ml), ? tetrakis(triphenylphosphine)palladium (0) [(Pd(PPh3)4] (180 mg, 0.156 mmol) was added): the resulting mixture was stirred at 110°C overnight, then cooled down to room temperature ( 25°C) and concentrated under vacuum.The residue obtained was purified by silica gel chromatography (eluent: dimethylcarbonate/petroleum ether, 3/7 v/v) obtaining a yellow oil corresponding to 5-(tert-butyl) -3-(5-(2-ethylhexyl)thiophen-2-yl)-2-hydroxybenzaldehyde (12) (0.86 g, yield: 74%).

<1>H NMR (300 MHz, CDCl3): ? 11.72 (s, 1H), 9.92 (s, 1H), 7.86 (d, J= 2.4 Hz, 1H), 7.47 (d, J= 3.6 Hz, 1H), 7.43 (d, J= 2.4 Hz, 1H), 6.78 (d, J= 3.6 Hz, 1H), 2.78 (d, J= 6.8 Hz, 2H), 1.68 ? 1.57 (m, 1H), 1.41 ? 1.26 (m, 17H), 0.94 ? 0.87 (m, 6H).

<13>C NMR (76 MHz, CDCl3): ? 197.27, 155.91, 145.14, 142.79, 135.69, 133.03, 128.87, 126.39, 125.75, 123.38, 120.58, 41.58, 34.33, 34.24, 32.53, 31.42 , 29.01, 25.65, 23.16, 14.30, 10.97.

HRMS (CI<+>): calculated for C23H32O2S (372.2123); found 372.2127(M)/373.2199(M 1).

Summary of Salen (XVIb)

In a 100 ml double-necked flask, a solution of 5-(tert-butyl)-3-(5-(2-ethylhexyl)thiophen-2-yl)-2-hydroxybenzaldehyde (12) obtained as described above (850 mg, 2.28 mmol) and (1R,2R)-cyclohexane-1,2-diamine (6) (130 mg, 1.14 mmol) in methanol (15 ml), ? been stirred all night. The mixture obtained? been concentrated under vacuum and the residue obtained ? Preparative size-exclusion recycling HPLC was purified to obtain an orange-red oil (0.79 g, yield: 96.3%) corresponding to Salen (XVIb) (0.785 g, yield: 83.6%).

<1>H NMR (300 MHz, CDCl3): ? 14.46 (s, 2H), 8.27 (s, 2H), 7.58 (dd, J= 7.7, 1.6 Hz, 2H), 7.39 (d, J= 3.6 Hz, 2H), 7.04 (dd, J= 7.6, 1.6 Hz , 2H), 6.80 (d, J= 7.7 Hz, 2H), 6.75 (d, J= 3.7 Hz, 2H), 3.42 ? 3.30 (m, 2H), 2.77 (d, J= 6.8Hz, 4H), 2.05 ? 1.85 (m, 4H), 1.84 ? 1.68 (m, 2H), 1.68 ? 1.58 (m, 2H), 1.52 ? 1.23 (m, 18H), 0.90 (t, J= 7.4Hz, 12H).

<13>C NMR (76 MHz, CDCl3): ? 165.63, 155.72, 144.35, 141.05, 137.18, 128.35, 127.31, 125.26, 125.11, 122.31, 118.30, 72.65, 41.57, 34.29, 34.09, 32.55 , 31.48, 29.04, 25.63, 24.38, 23.19, 14.32, 10.97.

MALDI-TOF MS (dithranol): 823.4.

HRMS (FAB): calculated for C52H74N2O2S2 (822.5192); found 822.5185. EXAMPLE 4

Summary of Salen (XVIc)

In a 250 ml double-necked flask, a mixture of 3,5-di-tert-butyl-2-hydroxybenzaldehyde (13) (6.64 g, 28.33 mmol) and 1,2,5-oxadiazol-3 ,4-diamine (14) (808 mg, 8.07 mmol) in methanol (60 ml) with a few drops of a glacial acetic acid, were refluxed overnight. Subsequently, the solvent ? been removed, through a rotary evaporator and the residue obtained? was purified by silica gel chromatography (eluent: petroleum ether/dichloromethane, 8/2, v/v) to obtain a yellow solid corresponding to Salen (XVIc) (370 mg, yield: 8%).

<1>H NMR (300 MHz, acetone-d6) ? 9.43 (s, 2H), 7.67 (d, J= 2.4 Hz, 2H), 7.59 (d, J= 2.4 Hz, 2H), 1.50 (s, 18H), 1.36 (s, 18H).

<13>C NMR (75 MHz, acetone-d6): ? 199.0, 173.6, 160.1, 159.7, 155.5, 155.5, 142.3, 142.2, 137.9, 137.8, 132.2, 131.5, 129.6, 129.6, 129.1, 118.8, 35.7, 34. 8, 31.6, 29.7.

HRMS (FAB) calculated for C32H44N4O3 [M<+>]: 532.3413; found: 532.3414.

EXAMPLE 5

Summary of Salen (XVId)

In a 250 ml double-necked flask, a mixture of 3,5-di-tert-butyl-2-hydroxybenzaldehyde (13) (533 mg, 3.37 mmol) and naphthalene-2,3-diamine (15) ( 2.09 g, 8.91 mmol) in methanol (50 ml) with a few drops of glacial acetic acid, ? refluxed overnight. Subsequently, the solvent ? been removed, through evaporation in a rotary evaporator and the residue obtained? was washed with cold methanol (3 x 5 ml) to obtain a yellow solid corresponding to Salen (XVId) (1.34 g, yield: 67%).

<1>H NMR (300 MHz, Chloroform-d) ? 8.77 (s, 2H), 7.93 ? 7.79 (m, 2H), 7.59 (s, 2H), 7.51 ? 7.43 (m, 4H), 7.28 (d, J= 2.4 Hz, 2H), 1.45 (s, 18H), 1.34 (s, 18H).

<13>C NMR (126MHz, DMSO) ? 165.5, 157.4, 141.6, 139.8, 135.8, 132.0, 127.1, 127.0, 125.6, 118.1, 116.3, 34.1, 33.4, 30.7, 29.9, 28.9.

HRMS (FAB) calculated for C40H50N2O2 [M<+>]: 590.3872; found: 590.3862.

EXAMPLE 6

Summary of Salen (XVIe)

Synthesis of 2-(tert-butyl)thiophene (16)

In a 250 mL double-necked flask, a stirred mixture of aluminum trichloride (AlCl3) (12.7 g, 95.28 mmol) in anhydrous dichloromethane (CH2Cl2) (40 mL) ? been cooled down to -78°C in an argon atmosphere. Next, a mixture of thiophene (8.02 g, 7.64 mL, 95.28 mmol) and tert-butyl chloride (8.82 g, 10.50 mL, 95.28 mmol) in anhydrous dichloromethane (CH2Cl2) (40 mL ) ? been added drop by drop in 10 minutes: the mixture obtained? been stirred for 1 hour and then ? was allowed to warm up to room temperature (25°C), under stirring, for 2 days. Next, the blend was poured into an ice bath, neutralized with aqueous sodium bicarbonate solution, and extracted with dichloromethane (CH2Cl2) (3 x 30 mL). The obtained organic phases were combined, washed with water (2 x 50 ml) and brine, dried over magnesium sulphate (MgSO4), filtered and the solvent ? been removed under vacuum. The oil obtained? was purified by column chromatography on silica gel (eluent: petroleum ether) to obtain a colorless oil corresponding to 2-(tert-butyl)thiophene (16) (8.3 g, 59.18 mmol, yield: 62% ).

<1>H NMR (300 MHz, CDCl3): ? 7.12 (dd, J = 5.1, 1.2 Hz, 1H), 6.92 (dd, J = 5.1, 3.5 Hz, 1H), 6.84 (dd, J = 3.5, 1.2 Hz, 1H), 1.40 (s, 9H).

Synthesis of tri-butyl (5-(2-tert-butyl)thiophen-2-yl) stannane (17)

In a 250 ml double-necked flask, a stirred solution of 2-(terbutyl)thiophene (16) obtained as above (5 g, 35.65 mmol) in anhydrous tetrahydrofuran (THF) (100 ml)? been cooled to 0?C, with an ice bath. During stirring, a solution of n-butyl lithium in hexane (2.5 M solution, 17.11 mL, 42.78 mmol), ? was added drop by drop, over 30 minutes. After another 30 minutes of stirring, at 0?C, ? tributyltin chloride (11.80 mL, 442.78 mmol) was added rapidly. Subsequently, the mixture obtained ? was heated up to 60°C and maintained at this temperature, under stirring, for 16 hours, subsequently cooled down to room temperature (25°C) and subjected to quenching with water. The mixture ? was extracted with ethyl acetate (3 x 25 ml), concentrated under vacuum and subsequently redissolved in ethyl acetate (50 ml). The solution obtained? was mixed with a saturated aqueous solution of sodium fluoride (NaF) (50 ml) and stirred for 15 minutes, obtaining a residue which ? was removed by filtration on celite and washed with ethyl acetate (2 x 10 ml). Subsequently, the obtained aqueous phases were combined, extracted with ethyl acetate (3 x 25 ml) and the obtained organic phases were combined and washed with brine (2 x 100 ml), subsequently dried over magnesium sulfate (MgSO4), filtered and the solvent? was removed, in vacuo, to obtain a crude light brown oil corresponding to tri-butyl(5-(2-tert-butyl)thiophen-2-yl)stannane (17) (16 g, 37.27 mmol, yield: 105% ) as crude tan oil, which ? was used without further purification.

Synthesis of 3-(5-(tert-butyl)thiophen-2-yl)-2-hydroxybenzaldehyde (18)

In a 250 ml double-necked flask, to a stirred mixture of tri-butyl(5-(2-tert-butyl)thiophen-2-yl)stannane (17) obtained as above (3.2 g, 7, 46 mmol) and 3-bromo-2-hydroxybenzaldehyde (1 g, 4.97 mmol) in degassed toluene (50 ml), ? tetrakis(triphenylphosphine)palladium(0) [(Pd(PPh3)4] (287 mg, 0.249 mmol) was added: the resulting mixture was stirred at 80°C overnight, then cooled down to room temperature ( 25°C) and concentrated under vacuum.The obtained residue was purified by silica gel chromatography (eluent: dichloromethane/petroleum ether, 1/1 v/v) obtaining a yellow oil corresponding to 3-(5-(ter -butyl)thiophen-2-yl)-2-hydroxybenzaldehyde (18) (0.81 g, yield: 62.5%).

<1>H NMR (300 MHz, CDCl3): ? 11.90 (s, 1H), 9.93 (s, 1H), 7.84 (dd, J = 7.7, 1.6 Hz, 1H), 7.48 ? 7.44 (m, 2H), 7.05 (t, J = 7.7 Hz, 1H), 6.85 (d, J = 3.8 Hz, 1H), 1.43 (s, 9H).

<13>C NMR (76 MHz, CDCl3): ? 197.04, 158.17, 158.00, 135.26, 134.48, 132.40, 126.43, 123.99, 122.03, 121.09, 120.01, 32.58.

HRMS (CI ): calculated for C15H16O2S (260.0871); found 260.0868 (M)/261.0950 (M 1).

Summary of Salen (XVIe)

In a 100 ml double-necked flask, a solution of 3-(5-(tert-butyl)thiophen-2-yl)-2-hydroxybenzaldehyde (18) obtained as described above (790 mg, 3.03 mmol) and (1R,2R)-cyclohexane-1,2-diamine (6) (173 mg, 1.52 mmol) in methanol (15 ml), ? been stirred all night. The mixture obtained? been concentrated under vacuum and the residue obtained ? was purified by recycle preparative size exclusion HPLC to obtain an orange-red oil (XVIe) (0.81 g, yield: 89%).

<1>H NMR (300 MHz, CDCl3): ? 14.40 (s, 2H), 8.27 (s, 2H), 7.57 (dd, J = 7.7, 1.6 Hz, 2H), 7.36 (d, J = 3.7 Hz, 2H), 7.04 (dd, J = 7.6, 1.6 Hz , 2H), 6.82 (d, J = 3.7 Hz, 2H), 6.78 (t, J = 7.7 Hz, 2H), 3.45 ? 3.27 (m, 2H), 2.04 ? 1.95 (m, 2H), 1.93 ? 1.84 (m, 2H), 1.79 (s, 2H), 1.52 ? 1.45 (m, 2H), 1.43 (s, 18H).

<13>C NMR (76 MHz, CDCl3): ? 165.35, 158.06, 157.35, 135.96, 130.92, 130.55, 125.12, 123.05, 121.54, 118.78, 118.53, 72.34, 34.67, 33.15, 32.63, 24.33 .

MALDI-TOF MS (dithranol): 598.1.

HRMS (FAB): calculated for C36H42N2O2S2 (598.2688); found 598.2679 (M)/599.2760 (M 1).

EXAMPLE 7

Summary of Salen (XVIf)

Synthesis of 5-(tert-butyl)-3-(5-(tert-butyl)thiophen-2-yl)-2-hydroxy-benzaldehyde (19) In a 250 ml double-necked flask, to a stirred solution of tributyl(5-(2-tert-butyl)thiophen-2-yl)stannane (17) obtained as reported in example 6 (3.01 g, 7.00 mmol) and 3-bromo-5-(tert-butyl) -2-hydroxybenzaldehyde (11) obtained as reported in example 3 (1.2 g, 4.67 mmol), in degassed toluene (50 ml), ? tetrakis(triphenylphosphine)palladium (0) [(Pd(PPh3)4] (270 mg, 0.233 mmol) was added: the resulting mixture was stirred at 80°C overnight, then cooled down to room temperature ( 25°C) and concentrated under vacuum.The obtained residue was purified by silica gel chromatography (eluent: dichloromethane/petroleum ether, 1/1 v/v) obtaining a yellow oil corresponding to 5-(tert-butyl) -3-(5-(tert-butyl)thiophen-2-yl)-2-hydroxybenzaldehyde (19) (0.99 g, yield: 67%).

<1>H NMR (300 MHz, CDCl3): ? 11.70 (s, 1H), 9.92 (s, 1H), 7.86 (d, J = 2.4 Hz, 1H), 7.46 ? 7.42 (m, 2H), 6.85 (d, J = 3.7 Hz, 1H), 1.43 (s, 9H), 1.37 (s, 9H).

<13>C NMR (76 MHz, CDCl3): ? 197.25, 157.91, 156.02, 142.80, 135.05, 133.31, 128.91, 126.38, 123.45, 122.04, 120.56, 32.60, 31.43.

HRMS (CI ): calculated for C19H24O2S (316.1497); found 316.1496 (M)/317.1577 (M 1).

Summary of Salen (XVIf)

In a 100 ml double-necked flask, a solution of 5-(tert-butyl)-3-(5-(tert-butyl)thiophen-2-yl)-2-hydroxybenzaldehyde (19) (1.18 g, 3, 73 mmol) obtained as above and (1R,2R)-cyclohexane-1,2-diamine (6) (213 mg, 1.86 mmol) in methanol (15 ml), ? been stirred all night. The mixture obtained? been concentrated under vacuum and the residue obtained ? was purified by recycle preparative size-exclusion HPLC to obtain a red-orange oil (XVIf), (1.21 g, 1.70 mmol, yield: 91%).

<1>H NMR (300 MHz, CDCl3): ? 14.11 (s, 2H), 8.28 (s, 2H), 7.57 (d, J = 2.4 Hz, 2H), 7.33 (d, J = 3.7 Hz, 2H), 7.04 (d, J = 2.4 Hz, 2H), 6.82 (d, J = 3.7Hz, 2H), 3.40 ? 3.25 (m, 2H), 2.01 ? 1.84 (m, 4H), 1.82 ? 1.64 (m, 2H), 1.52 ? 1.45 (m, 2H), 1.43 (s, 18H), 1.25 (s, 18H).

<13>C NMR (76 MHz, CDCl3): ? 165.64, 157.14, 155.77, 141.04, 136.53, 128.71, 127.39, 125.15, 122.38, 121.55, 118.27, 72.65, 34.66, 34.08, 33.31, 32.65 , 31.49, 24.39.

MALDI-TOF MS (DCTB): 710.2.

HRMS (FAB ): calculated for C44H58N2O2S2 (710.3940); found 710.3931 (M)/711.4023 (M 1).

EXAMPLE 8

Synthesis of Salen (XVIg)

Synthesis of 2-bromo-5-(tert-butyl)thiophene (20)

In a 100 ml double-necked flask, shielded from light and cooled with an ice bath, to a stirred solution of 2-(tert-butyl)thiophene (16) (3.3 g, 23.53 mmol) obtained as disclosed in example 6, in dimethylformamide (DMF) (10 mL), a solution of N-bromosuccinimide (5.03 g, 28.24 mmol) in dimethylformamide (DMF) (20 mL) ? been added drop by drop, in 30 minutes: the mixture obtained? been left to reach room temperature (25?C), stirred overnight and, subsequently, the solvent ? been removed under vacuum. Subsequently water (100 ml) and petroleum ether (100 ml) were added to obtain an aqueous phase and an organic phase which were separated through a separating funnel. Subsequently, the aqueous phase ? was extracted with petroleum ether (2 x 50 ml) and the organic phases obtained were combined and washed with brine (100 ml) and water (100 ml), subsequently dried over magnesium sulphate (MgSO4), filtered and the solvent ? been removed, vacuum packed. The oil obtained? was purified by silica gel chromatography [eluent: petroleum ether] to obtain a pale yellow oil corresponding to 2-bromo-5-(tert-butyl)thiophene (20) (3.34 g, yield: 65%).

<1>H NMR (300 MHz, CDCl3): ? 6.84 (d, J = 3.8 Hz, 1H), 6.57 (d, J = 3.8 Hz, 1H), 1.35 (s, 9H).

Synthesis of 5-(tert-butyl)-2,2'-bithiophene (22)

In a 100 ml double-necked flask, a solution of Grignard's reagent (21) ? been prepared by treating 2-bromothiophene (2.86 g, 1.70 ml, 17.53 mmol) with magnesium chips (667 mg, 27.43 mmol) in anhydrous diethyl ether (25 ml) and the solution obtained ? was refluxed for 45 minutes under argon. The Grignard solution obtained ? was added dropwise in a 250 ml double-necked flask over 60 minutes under argon at 0°C to a stirred suspension of [1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium(II) complex with dichloromethane (CH2Cl2) [Pd(dppf)Cl2<.>CH2Cl2] (124 mg, 0.152 mmol) and 2-bromo-5-(tert-butyl) thiophene (20) obtained as above (3.34 g, 15.24 mmol) in anhydrous diethyl ether (10 ml). The mixture obtained? was allowed to reach room temperature (25°C) and stirred for 23 hours: subsequently, methanol (20 ml) ? been added to finish the reaction and the mixture ? filtered through a double layer of magnesium sulfate (MgSO4)/silica (1.5cm/2.5cm). Next, the double layer ? been eluted with diethyl ether (30 ml) and the solvent ? been removed through a rotary evaporator obtaining a yellow oily liquid which? was purified by silica gel chromatography (eluent: petroleum ether) to obtain a pale yellow oil corresponding to 5-(tert-butyl)-2,2'-bithiophene (22) (2.52 g, yield: 74%) .

<1>H NMR (300 MHz, CDCl3): ? 7.17 (dd, J = 5.2, 1.1 Hz, 1H), 7.11 (dd, J = 3.6, 1.1 Hz, 1H), 7.00 (d, J = 3.6 Hz, 1H), 6.98 (dd, J = 3.6, 1.2 Hz , 1H), 6.73 (d, J = 3.7 Hz, 1H), 1.40 (s, 9H).

Synthesis of 5-bromo -5'-(tert-butyl)-2,2'-bithiophene (23)

In a 100 ml double-necked flask, shielded from light and cooled with an ice bath, to a stirred solution of 5-(tert-butyl)-2,2'-bithiophene (22) obtained as reported above (2, 17 g, 9.76 mmol) in dimethylformamide (DMF) (10 ml) ? a solution of N-bromosuccinimide (2.08 g, 11.71 mmol) in dimethylformamide (DMF) (20 ml) was added dropwise, over 30 minutes: the mixture obtained ? been left to reach room temperature (25?C), stirred overnight and subsequently the solvent ? been removed under vacuum. Subsequently water (100 ml) and petroleum ether (100 ml) were added to obtain an aqueous phase and an organic phase which were separated through a separating funnel. Subsequently, the aqueous phase ? was extracted with petroleum ether (2 x 50 ml) and the organic phases obtained were combined and washed with brine (100 ml) and water (100 ml), subsequently dried over magnesium sulphate (MgSO4), filtered and the solvent ? been removed, under vacuum, obtaining an oil that ? was purified by silica gel chromatography (eluent: petroleum ether) to obtain a yellow oil corresponding to 5-bromo-5'-(tertbutyl)-2,2'-bithiophene (23), (2.2 g, 75% ).

<1>H NMR (300 MHz, CDCl3): ? 6.94 (d, J = 3.8 Hz, 1H), 6.91 (d, J = 3.7 Hz, 1H), 6.83 (d, J = 3.8 Hz, 1H), 6.72 (d, J = 3.7 Hz, 1H), 1.39 ( s, 9H).

Synthesis of tri-butyl (5'-(tert-butyl)-[2,2'-bitiophen]-5-yl)stannane (24)

A stirred solution of 5-bromo-5'-(tert-butyl)-2,2'-bithiophene (23) obtained as above (1 g, 3.32 mmol) in anhydrous tetrahydrofuran (THF) (30 ml) in a 250 ml double-necked flask, ? been cooled down to 0?C, in an ice bath. During stirring, a solution of n-butyl lithium in hexane (2.5 M solution, 1.59 mL, 3.98 mmol), ? was added drop by drop, over 30 minutes. After another 30 minutes of stirring, at 0?C, ? tri-butyltin-chloride (1.37 mL, 4.98 mmol) was added rapidly. Subsequently, the mixture obtained ? was heated up to 60°C and maintained at this temperature, under stirring, for 16 hours, subsequently cooled down to room temperature (25°C) and subjected to quenching with water. The mixture ? was extracted with ethyl acetate (50 ml), concentrated under vacuum and subsequently redissolved in ethyl acetate (100 ml). The solution obtained? was mixed with a saturated aqueous solution of sodium fluoride (NaF) (100 ml) and stirred for 15 minutes, obtaining a white precipitate which was was removed by filtration on celite and washed with ethyl acetate (2 x 20 ml) obtaining an aqueous phase and an organic phase which were separated through a separating funnel. Subsequently, the aqueous phase ? was extracted with ethyl acetate (2 x 30 ml) and the obtained organic phases were combined and washed with water (2 x 100 ml), subsequently dried over magnesium sulphate (MgSO4), filtered and the solvent ? was removed, in vacuo, to obtain tri-butyl(5'-(tert-butyl)-[2,2'-bitiophen]-5-yl)stannane (24) (1.65 g, yield: 97%) as oil light brown what? was used without further purification.

Synthesis of 3-(5'-(tert-butyl)-[2,2'-bitiophen]-5-yl)-2-hydroxybenzaldehyde (25)

In a 250 ml double-necked flask, to a stirred mixture of tri-butyl(5'-(terbutyl)-[2,2'-bitiophen]-5-yl)stannane (24) obtained as described above (1, 65 g, 3.23 mmol) and 3-bromo-2-hydroxybenzaldehyde (668 mg, 3.32 mmol) in degassed toluene (40 mL), ? tetrakis (triphenylphosphine)palladium (0) [(Pd(PPh3)4] (384 mg, 0.332 mmol) was added: the resulting mixture was stirred at 80°C overnight, then cooled down to room temperature ( 25°C) and concentrated under vacuum.The obtained residue was purified by silica gel chromatography (eluent: dichloromethane/petroleum ether, 1/1 v/v) obtaining an orange powder corresponding to 3-(5'-( tert-Butyl)-[2,2'-bitiophen]-5-yl)-2-hydroxybenzaldehyde (25) (0.72 g, yield: 63%).

<1>H NMR (300 MHz, CDCl3): ? 11.98 (s, 1H), 9.94 (s, 1H), 7.88 (dd, J = 7.7, 1.4 Hz, 1H), 7.56 (d, J = 3.9 Hz, 1H), 7.49 (dd, J = 7.6, 1.4 Hz , 1H), 7.12 (d, J = 3.9 Hz, 1H), 7.07 (t, J = 7.8 Hz, 1H), 7.04 (d, J = 3.7 Hz, 1H), 6.75 (d, J = 3.7 Hz, 1H ), 1.41 (s, 9H).

<13>C NMR (76 MHz, CDCl3): ? 197.03, 157.98, 157.33, 138.44, 135.75, 134.84, 134.35, 132.68, 127.28, 123.43, 123.38, 123.34, 122.28, 121.15, 120.12, 3 4.84, 32.53.

MALDI-TOF MS (DCTB): 342.0.

HRMS (CI<+>): calculated for C19H18O2S2 (342.0748); found 342.0743. Synthesis of Salen (XVIg)

In a 250 ml double-necked flask, a solution of 3-(5'-(tert-butyl)-[2,2'-bitiophen]-5-yl)-2-hydroxybenzaldehyde (25) obtained as described above ( 750 mg, 2.19 mmol) and (1R,2R)-cyclohexane-1,2-diamine (6) (125 mg, 2.19 mmol) in methanol (25 ml), ? been stirred all night. The mixture obtained? been concentrated under vacuum and the residue obtained ? was purified by recycle preparative size-exclusion HPLC to obtain a red-orange oil (XVIg) (0.69 g, yield: 83%).

<1>H NMR (300 MHz, CDCl3): ? 14.58 (s, 1H), 8.28 (s, 1H), 7.61 (dd, J = 7.8, 1.5 Hz, 1H), 7.47 (d, J = 3.9 Hz, 1H), 7.11 (d, J = 3.9 Hz, 1H ), 7.08 ? 7.02 (m, 2H), 6.79 (d, J = 7.7 Hz, 1H), 6.75 (d, J = 3.7 Hz, 1H), 3.44 ? 3.31 (m, 1H), 2.06 ? 1.96 (m, 1H), 1.96 ? 1.86 (m, 1H), 1.84 ? 1.68 (m, 1H), 1.53 ? 1.45 (m, 1H), 1.41 (s, 9H).

<13>C NMR (76 MHz, CDCl3): ? 165.29, 158.44, 156.77, 137.68, 137.39, 134.86, 130.86, 130.45, 125.85, 123.03, 122.89, 122.54, 122.18, 118.75, 118.53, 7 2.18, 34.79, 33.11, 32.54, 24.31.

HRMS (FAB): calculated for C44H46N2O2S4 (762.2442); found 762.2435. EXAMPLE 9

Summary of Salen (XVIh)

Synthesis of 5-(tert-butyl)-3-(5'-(tert-butyl)-[2,2'-bitiophen]-5-yl)-2-hydroxybenzaldehyde (26)

In a 250 ml double-necked flask, add a stirred mixture of tri-butyl (5'(ter-butyl)-[2,2'-bitiophen]-5-yl)stannane (24) obtained as reported in example 8 (1.5 g, 2.93 mmol) and 3-bromo-5-(tert-butyl)-2-hydroxybenzaldehyde (11) obtained as reported in example 3 (754 mg, 2.93 mmol), in degassed toluene ( 40ml), ? tetrakis (triphenylphosphine) palladium (0) [(Pd(PPh3)4] (169 mg, 0.147 mmol) was added): the resulting mixture was stirred at 80°C overnight, then cooled down to room temperature ( 25°C) and concentrated under vacuum.The obtained powder was purified by silica gel chromatography (eluent: dichloromethane/petroleum ether, 1/1 v/v) to obtain a corresponding orange powder to give 5-(tert-butyl )-3-(5'-(tert-butyl)-[2,2'-bitiophen]-5-yl)-2-hydroxybenzaldehyde (26) (0.66 g, yield: 56%).

<1>H NMR (300 MHz, CDCl3): ? 11.78 (s, 1H), 9.93 (s, 1H), 7.90 (d, J = 2.4 Hz, 1H), 7.56 (d, J = 3.9 Hz, 1H), 7.47 (d, J = 2.4 Hz, 1H), 7.12 (d, J = 3.9 Hz, 1H), 7.04 (d, J = 3.7 Hz, 1H), 6.75 (d, J = 3.7 Hz, 1H), 1.41 (s, 9H), 1.38 (s, 9H).

<13>C NMR (76 MHz, CDCl3): ? 197.25, 157.24, 156.00, 142.95, 138.17, 136.36, 134.42, 132.74, 129.29, 127.24, 123.41, 123.28, 122.85, 122.28, 120.66, 3 4.83, 34.38, 32.54, 31.43.

HRMS (EI): calculated for C23H26O2S2 (398.1374); found 398.1373 Summary of Salen (XVIh)

In a 100 ml double-necked flask, a solution of 3-(5'-(tert-butyl)-[2,2'-bitiophen]-5-yl)-2-hydroxybenzaldehyde (26) obtained as described above ( 655 mg, 1.64 mmol) and (1R, 2R)-cyclohexane-1,2-diamine (6) (94 mg, 0.822 mmol) in methanol (25 mL), ? been stirred all night. The mixture obtained? been concentrated under vacuum and the residue obtained ? was purified by recycle preparative size-exclusion HPLC to obtain an orange-red powder (XVIh) (0.70 g, 0.799 mmol, yield: 97%).

<1>H NMR (300 MHz, CDCl3): ? 14.26 (s, 1H), 8.30 (s, 1H), 7.62 (d, J = 2.4 Hz, 1H), 7.46 (d, J = 3.9 Hz, 1H), 7.10 (d, J = 3.8 Hz, 1H), 7.07 (d, J = 2.4 Hz, 1H), 7.02 (d, J = 3.6 Hz, 1H), 6.74 (d, J = 3.7 Hz, 1H), 3.43 ? 3.31 (m, 1H), 2.03 ? 1.94 (m, 1H), 1.94 ? 1.86 (m, 1H), 1.86 ? 1.70 (m, 1H), 1.51 ? 1.44 (m, 1H), 1.41 (s, 9H), 1.25 (s, 9H).

<13>C NMR (76 MHz, CDCl3): ? 165.62, 156.71, 156.09, 141.16, 138.02, 137.47, 134.90, 128.09, 127.74, 125.90, 123.08, 122.84, 122.16, 121.83, 118.33, 7 2.54, 34.79, 34.12, 33.27, 32.55, 31.47, 24.39.

HRMS (FAB): calculated for C52H62N2O2S4 (874.3694); found 874.3684. EXAMPLE 10

Synthesis of Salen (XVIj)

Synthesis of 2-bromo-5-(n-hexyl)thiophene (28)

In a 250 ml double-necked flask, shielded from light and cooled with an ice bath, to a stirred solution of 2-n-hexylthiophene (27) (5.12 g, 5.49 mmol) in dimethylformamide (DMF) (15ml) ? a solution of N-bromosuccinimide (6.5 g, 36.51 mmol) in dimethylformamide (DMF) (25 ml) was added dropwise, over 30 minutes: the solution obtained ? been left to reach room temperature (25?C), stirred overnight and subsequently the solvent ? been removed under vacuum. Subsequently water (100 ml) and petroleum ether (100 ml) were added to obtain an aqueous phase and an organic phase which were separated through a separating funnel. Subsequently, the aqueous phase ? was extracted with petroleum ether (2 x 50 ml) and the organic phases obtained were combined and washed with brine (100 ml) and water (100 ml), subsequently dried over magnesium sulphate (MgSO4), filtered and the solvent ? been removed, under vacuum, obtaining an oil that ? was purified by silica gel chromatography (eluent: petroleum ether) to obtain a yellow oil corresponding to 2-bromo-5-(n-hexyl)thiophene (28) (7.12 g, yield: 95%).

<1>H NMR (300 MHz, CDCl3): ? 6.84 (d, J = 3.6 Hz, 1H), 6.53 (dt, J = 3.6, 0.9 Hz, 1H), 2.74 (dt, J = 7.5, 0.9 Hz, 2H), 1.69 ? 1.56 (m, 2H), 1.40 ? 1.25 (m, 6H), 0.89 (t, J = 6.8Hz, 3H).

Synthesis of 5-(n-Hexyl)-2,2'-bithiophene (29)

A solution of Grignard's reagent (21) (33.12 mmol) in anhydrous diethyl ether (25 ml) prepared as reported in example 8, ? was added dropwise in a 250 ml double-necked flask over 30 minutes under argon at 0°C to a stirred suspension of [1,1'-bis(diphenylphosphino)ferrocene]-dichloropalladium(II) complex ) with dichloromethane (CH2Cl2) [Pd(dppf) Cl2<.>CH2Cl2] (234 mg, 0.228 mmol) and 2-bromo-5-(n-hexyl) thiophene (28) obtained as above (7.12 g, 28.80 mmol) in anhydrous diethyl ether (25 ml). The mixture obtained? was allowed to reach room temperature (25°C) and stirred for 23 hours: subsequently, methanol (20 ml) ? been added to finish the reaction and the mixture ? filtered through a double layer of magnesium sulfate (MgSO4) /silica (1.5cm/2.5cm). Next, the double layer ? been eluted with diethyl ether (30 ml) and the solvent ? been removed through a rotary evaporator obtaining a yellow oily liquid which? was purified by silica gel chromatography (eluent: petroleum ether) to obtain a yellow oil corresponding to 5-(n-hexyl)-2,2'-bithiophene (29) (6.96 g, 27.79 mmol yield: 96%).

<1>H NMR (300 MHz, CDCl3): ? 7.16 (dd, J = 5.1, 0.7 Hz, 1H), 7.10 (dd, J = 3.6, 1.0 Hz, 1H), 7.00 (d, J = 4.2 Hz, 1H), 6.98 (d, J = 3.6 Hz, 1H ), 6.68 (dd, J = 3.5, 0.6 Hz, 1H), 2.79 (t, J = 7.6 Hz, 2H), 1.76 ? 1.62 (m, 2H), 1.44 ? 1.26 (m, 6H), 0.90 (t, J = 6.7Hz, 3H).

Synthesis of 5-bromo-5'-(n-hexyl)-2,2'-bithiophene (30)

In a 250 ml double-necked flask, shielded from light and cooled with an ice bath, to a stirred solution of 5-(n-butyl)-2,2'-bithiophene (29) obtained as reported above (6, 96 g, 27.79 mmol) in dimethylformamide (DMF) (10 ml) ? was added dropwise a solution of N-bromosuccinimide (5.94 g, 33.35 mmol) in dimethylformamide (DMF) (20 ml), over 30 minutes: the solution obtained ? been left to reach room temperature (25?C), stirred overnight and subsequently the solvent ? been removed under vacuum. Subsequently water (100 ml) and petroleum ether (100 ml) were added to obtain an aqueous phase and an organic phase which were separated through a separating funnel. Subsequently, the aqueous phase ? was extracted with petroleum ether (2 x 50 ml) and the organic phases obtained were combined and washed with brine (100 ml) and water (100 ml), subsequently dried over magnesium sulphate (MgSO4), filtered and the solvent ? been removed, under vacuum, obtaining an oil that ? was purified by silica gel chromatography (eluent: petroleum ether) to obtain a yellow oil corresponding to 5-bromo-5'-(n-hexyl)-2,2'-bithiophene (30), (9.00 g, yield: 98%).

<1>H NMR (300 MHz, CDCl3): ? 6.94 (d, J = 3.8 Hz, 1H), 6.91 (d, J = 3.6 Hz, 1H), 6.83 (d, J = 3.8 Hz, 1H), 6.66 (dt, J = 3.6, 0.9 Hz, 1H), 2.78 (t, J = 7.6Hz, 2H), 1.73 ? 1.61 (m, 2H), 1.43 ? 1.23 (m, 6H), 0.89 (t, J = 6.8Hz, 3H).

Synthesis of tri-butyl(5'-(n-hexyl)-[2,2 -bitiophen]-5-yl)stannane (31)

A stirred solution of 5-bromo-5'-(n-hexyl)-2,2'-bithiophene (30) obtained as above (4.50 g, 13.66 mmol) in anhydrous tetrahydrofuran (THF) (50 ml ) in a 250 ml two-necked flask, ? been cooled to 0?C, in an ice bath. While stirring, a solution of n-butyl lithium in hexane (2.5 M solution, 6.56 mL, 16.40 mmol), ? was added drop by drop, over 30 minutes. After another 30 minutes of stirring, at 0?C, ? Tributyltin chloride (4.71 mL, 16.40 mmol) was added rapidly. Subsequently, the mixture obtained ? was heated up to 60°C and maintained at this temperature, under stirring, for 16 hours, subsequently cooled down to room temperature (25°C) and subjected to quenching with water. The reaction mixture obtained ? been extracted with ethyl acetate (50 ml), obtaining a mixture that ? was concentrated under vacuum and subsequently redissolved in ethyl acetate (100 ml). The solution obtained? was mixed with a saturated aqueous solution of sodium fluoride (NaF) (100 ml) and stirred for 15 minutes, obtaining a residue which ? was removed by filtration on celite and washed with ethyl acetate (2 x 30 ml) obtaining an aqueous phase and an organic phase which were separated through a separating funnel. Subsequently, the aqueous phase ? was extracted with ethyl acetate (3 x 30 ml) and the organic phases obtained were combined and washed with brine (2 x 100 ml), subsequently dried over magnesium sulphate (MgSO4), filtered and the solvent ? was removed, in vacuo, to obtain a light brown oil corresponding to tri-butyl(5'-(n-hexyl)-[2,2'-bitiophen]-5-yl)stannane (31) (7.1 g, yield : 97%) what ? was used without further purification.

Synthesis of 3-(5'-n-Hexyl-[2,2'-bitiophen]-5-yl)-2-hydroxybenzaldehyde (32)

In a 250 ml double-necked flask, to a stirred mixture of tri-butyl(5'-(nesyl)-[2,2'-bitiophen]-5-yl)stannane (31) obtained as reported above (3, 02 g, 5.60 mmol) and 3-bromo-2-hydroxybenzaldehyde (750 mg, 3.73 mmol) in degassed toluene (40 ml), ? tetrakis (triphenylphosphine)palladium(0) [(Pd(PPh3)4] (216 mg, 0.186 mmol) was added: the resulting mixture was stirred at 80°C overnight, then cooled down to room temperature ( 25°C) and concentrated under vacuum.The obtained residue was purified by silica gel chromatography (eluent: dichloromethane/petroleum ether, 1/1 v/v) obtaining an orange powder corresponding to 3-(5'-n -hexyl-[2,2'-bitiophen]-5-yl)-2-hydroxybenzaldehyde (32) (0.993 g, 2.68 mmol, yield: 72%).

<1>H NMR (300 MHz, CDCl3): ? 11.98 (s, 1H), 9.93 (s, 1H), 7.87 (dd, J = 7.8, 1.5 Hz, 1H), 7.55 (d, J = 3.9 Hz, 1H), 7.49 (dd, J = 7.6, 1.6 Hz , 1H), 7.11 (d, J = 3.9 Hz, 1H), 7.08 (d, J = 7.7 Hz, 1H), 7.04 (d, J = 3.6 Hz, 1H), 6.70 (d, J = 3.5 Hz, 1H ), 2.80 (t, J = 7.6Hz, 2H), 1.75 ? 1.57 (m, 2H), 1.45 ? 1.24 (m, 6H), 0.93 (t, J = 7.4Hz, 3H).

<13>C NMR (76 MHz, CDCl3): ? 197.02, 157.98, 145.81, 138.42, 135.70, 134.85, 132.69, 127.28, 124.98, 123.57, 123.35, 121.14, 120.12, 31.72, 30.35, 28. 91, 22.72, 14.23, 13.74.

HRMS (CI<+>): calculated for C21H22O2S2 (370.1061); found 370.1055. Synthesis of Salen (XVIj)

In a 100 ml double-necked flask, a solution of 3-(5'-n-hexyl-[2,2'bitiophen]-5-yl)-2-hydroxybenzaldehyde (32) obtained as described above (980 mg, 2.64 mmol) and (1R,2R)-cyclohexane-1,2-diamine (6) (151 mg, 1.32 mmol) in methanol (25 ml), ? been stirred all night. The mixture obtained? been concentrated under vacuum and the residue obtained ? was purified by recycle preparative size-exclusion HPLC to yield an orange-red powder (XVIj) (687 mg, 63%).

<1>H NMR (300 MHz, CDCl3): ? 14.58 (s, 1H), 8.27 (s, 1H), 7.61 (dd, J = 7.8, 1.5 Hz, 1H), 7.47 (d, J = 3.9 Hz, 1H), 7.10 (d, J = 3.8 Hz, 1H ), 7.07 ? 7.01 (m, 2H), 6.77 (t, J = 7.7 Hz, 1H), 6.69 (d, J = 3.5 Hz, 1H), 3.41 ? 3.29 (m, 1H), 2.80 (t, J = 7.6Hz, 2H), 2.05 ? 1.94 (m, 1H), 1.94 ? 1.85 (m, 1H), 1.83 ? 1.74 (m, 1H), 1.74 ? 1.63 (m, 2H), 1.48 ? 1.42 (m, 1H), 1.41 ? 1.29 (m, 6H), 0.91 (t, J = 6.8Hz, 3H).

<13>C NMR (76 MHz, CDCl3): ? 165.28, 158.47, 145.26, 137.66, 137.35, 135.30, 130.87, 130.46, 125.85, 124.89, 123.13, 123.02, 122.52, 118.73, 118.51, 7 2.15, 10.33, 31.72, 30.34, 28.92, 24.30, 22.72, 14.23.

HRMS (FAB+): calculated for C48H54N2O2S4 (818.3068); found 818.3062. EXAMPLE 11

Summary of Salen (XVIk)

Synthesis of 5-(tert-butyl)-3-(5'-n-hexyl-[2,2'-bitiophen]-5-yl)-2-hydroxy-benzaldehyde (33) In a 250 g double-necked flask ml, to a stirred mixture of tri-butyl(5'-(nesyl)-[2,2'-bitiophen]-5-yl)stannane (31) obtained as reported in example 10 (2.36 g, 4.38 mmol) and 3-bromo-5-tert-butyl-2-hydroxybenzaldehyde (11) obtained as reported in example 3 (750 mg, 2.92 mmol) in degassed toluene (40 ml), tetrakis (triphenylphosphine) palladium(0) [(Pd(PPh3)4] (169 mg, 0.146 mmol) was added: the obtained mixture was stirred, at 80°C, overnight, subsequently cooled down to room temperature (25°C) and concentrated under The resulting residue was purified by silica gel chromatography (eluent: dichloromethane/petroleum ether, 1/1 v/v) to obtain an orange powder corresponding to 5-(tert-butyl)-3-(5'- n-Hexyl-[2,2'-bitiophen]-5-yl)-2-hydroxybenzaldehyde (33) (0.707 g, yield: 57%).

<1>H NMR (300 MHz, CDCl3): ? 11.77 (s, 1H), 9.93 (s, 1H), 7.89 (d, J = 2.4 Hz, 1H), 7.55 (d, J = 3.9 Hz, 1H), 7.47 (d, J = 2.4 Hz, 1H), 7.11 (d, J = 3.9 Hz, 1H), 7.04 (d, J = 3.5 Hz, 1H), 6.70 (d, J = 3.6 Hz, 1H), 2.80 (t, J = 7.6 Hz, 2H), 1.75 ? 1.63 (m, 2H), 1.38 (s, 9H), 1.36 ? 1.28 (m, 6H), 0.90 (t, J = 7.3Hz, 3H).

<13>C NMR (76 MHz, CDCl3): ? 197.24, 156.01, 145.74, 142.95, 138.17, 136.32, 134.87, 132.76, 129.30, 127.24, 124.98, 123.52, 123.39, 122.85, 120.66, 3 4.38, 31.72, 31.44, 30.36, 28.92, 22.73, 14.23. HRMS (CI ): calculated for C25H30O2S2 (426.1687); found 426.1682.

Summary of Salen (XVIk)

In a 100 ml double-necked flask, a solution of 5-(tert-butyl)-3-(5?-hexyl-[2,2'-bitiophen]-5-yl)-2-hydroxybenzaldehyde (33) obtained as reported above (700 mg, 1.64 mmol) and (1R,2R)-cyclohexane-1,2-diamine (6) (94 mg, 0.820 mmol) in methanol (25 ml), ? been stirred all night. The mixture obtained? been concentrated under vacuum and the residue obtained ? was purified by recycle preparative size exclusion HPLC to obtain an orange-red powder corresponding to Salen (XVIk) (750 mg, yield: 98%) as an orange-red powder.

<1>H NMR (300 MHz, CDCl3): ? 14.29 (s, 1H), 8.31 (s, 1H), 7.63 (d, J = 2.4 Hz, 1H), 7.45 (d, J = 3.8 Hz, 1H), 7.10 (d, J = 3.8 Hz, 1H), 7.08 (d, J = 2.4 Hz, 1H), 7.03 (d, J = 3.5 Hz, 1H), 6.69 (d, J = 3.6 Hz, 1H), 3.43 ? 3.32 (m, 1H), 2.80 (t, J = 7.6Hz, 2H), 2.05 ? 1.94 (m, 1H), 1.94 ? 1.86 (m, 1H), 1.81 ? 1.74 (m, 1H), 1.75 ? 1.63 (m, 2H), 1.54 ? 1.47 (m, 1H), 1.47 ? 1.27 (m, 6H), 1.25 (s, 9H), 0.91 (t, J = 6.8 Hz, 3H).

<13>C NMR (76 MHz, CDCl3): ? 165.60, 156.11, 145.21, 141.15, 137.98, 137.47, 135.34, 128.11, 127.74, 125.89, 124.86, 123.09, 123.06, 121.83, 118.32, 7 2.52, 34.11, 33.26, 31.72, 31.46, 30.34, 28.91, 24.37, 22.72, 14.23.

HRMS (FAB): calculated for C56H70N2O2S4 (930.4320); found 930.4325. EXAMPLE 12

Synthesis of Salen (XVIm)

In a 250 ml double-necked flask, a mixture of 8-hydroxy-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-pyrido[3,2,1-ij ]quinoline-9-carbaldehyde (34) (538 mg, 4.71 mmol) and (1R,2R)-cyclohexane-1,2-diamine (6) (3.1 g, 11.34 mmol) in methanol (50 ml) with 2-3 drops of a glacial acetic acid ? been subjected to reflux throughout the night obtaining a residue that ? was filtered and washed with cold methanol (3 x 5 ml) to obtain a yellow solid corresponding to Salen (XVIm) (2.63 g, yield: 89%).

<1>H NMR (500MHz, DMSO-d6) ? 8.05 (s, 2H), 6.75 (s, 2H), 3.25 ? 3.11 (m, 6H), 3.10 ? 3.04 (m, 4H), 1.97 ? 1.74 (m, 4H), 1.70 ? 1.42 (m, 12H), 1.41 ? 1.36 (m, 12H), 1.16 (s, 6H), 1.12 (s, 6H).

<13>C NMR (126MHz, DMSO-d6) ? 163.7, 160.1, 144.8, 126.6, 121.0, 113.6, 107.9, 69.9, 46.2, 45.8, 35.9, 32.4, 31.2, 30.8, 30.3, 30.2, 27.9, 27.9, 23.5.

HRMS (FAB) calculated for C40H56N4O2 [M<+>]: 624.9140; found: 625.4481.

EXAMPLE 13

Synthesis of Cr(Ia)Cl

In a 100 ml double-necked flask, Salen (XVIc) obtained as reported in example 4 (370 mg, 0.69 mmol) and chromium(II) chloride (CrCl2) (98 mg, 0.80 mmol), are were dissolved in anhydrous tetrahydrofuran (THF) (10 ml) and stirred, under argon, for 6 hours. Subsequently, the reaction mixture ? been exposed to air and agitated for 3 hours, and ? was subsequently added ethyl acetate (30 ml). Subsequently, the mixture obtained ? been washed with a saturated aqueous solution of ammonium chloride (NH4Cl) (3 x 50 ml), dried over magnesium sulphate (MgSO4) and the solvent ? been removed, under vacuum, obtaining a residue that ? was purified by dicalite filtration to obtain a dark purple powder corresponding to Cr(Ia)Cl (0.345 g, yield: 80%).

HRMS (FAB) calculated for C32H42CrN4O3 [M<+>-Cl]: 582.2662; found: 582.2654.

EXAMPLE 14

Synthesis of Cr(Ib)Cl

In a 100 ml double-necked flask, Salen (XVId) obtained as reported in example 5 (1 g, 1.69 mmol) and chromium (II) chloride (CrCl2) (350 mg, 2.84 mmol), are were dissolved in anhydrous tetrahydrofuran (THF) (20 ml) and stirred, under argon, for 6 hours. Subsequently, the reaction mixture ? been exposed to air and agitated for 3 hours, and ? was subsequently added ethyl acetate (50 ml). Subsequently, the mixture obtained ? been washed with ammonium chloride (NH4Cl) (3 x 50 ml), dried over magnesium sulphate (MgSO4) and the solvent ? been removed, under vacuum, obtaining a residue that ? was purified by dicalite filtration to obtain a dark purple powder corresponding to Cr(Ia)Cl (720 mg, yield: 63%).

HRMS (FAB) calculated for C40H48CrN2O2 [M<+>-Cl]: 640.3121; found: 640.3115.

EXAMPLE 15

Synthesis of Cr(Ic)Cl

In a 100 ml double-necked flask, Salen (XVIa) obtained as reported in example 2 (785 mg, 1.10 mmol) and chromium(II) chloride (CrCl2) (163 mg, 1.32 mmol), are were dissolved in anhydrous tetrahydrofuran (THF) (20 ml) and stirred under argon, at room temperature (25°C), overnight. Subsequently, the reaction mixture ? been exposed to air, stirred for 12 hours, and the solvent ? been removed, under vacuum, obtaining a residue that ? washed with saturated aqueous ammonium chloride (NH4Cl) solution (50 ml), filtered, and washed again with aqueous ammonium chloride (NH4Cl) solution (30 ml) and water (25 ml) to obtain a brown powder corresponding to Cr(Ic)Cl (652 mg, yield: 74%).

MALDI-TOF MS (DCTB): 795.5

EXAMPLE 16

Synthesis of Cr(Id)Cl

In a 100 ml double-necked flask, Salen (XVIb) obtained as reported in example 3 (780 mg, 0.947 mmol) and chromium(II) chloride (CrCl2) (139 mg, 1.14 mmol), were dissolved in anhydrous tetrahydrofuran (THF) (20 ml) and stirred under argon, at room temperature (25°C), overnight. Subsequently, the reaction mixture ? been exposed to air, stirred for 12 hours, and the solvent ? been removed, under vacuum, obtaining a residue that ? was washed with saturated aqueous ammonium chloride (NH4Cl) solution (50 ml), filtered and washed again with saturated aqueous ammonium chloride (NH4Cl) (50 ml) and water (50 ml) solution to obtain a powder brown corresponding to Cr(Id)Cl (753 mg, yield: 87%).

MALDI-TOF MS (DCTB): 907.7.

EXAMPLE 17

Synthesis of Cr(Ie)Cl

In a 100 ml double-necked flask, Salen (XVIe) obtained as reported in example 6 (810 mg, 1.35 mmol) and chromium(II) chloride (CrCl2) (199 mg, 1.62 mmol), are were dissolved in anhydrous tetrahydrofuran (THF) (20 ml) and stirred under argon, at room temperature (25°C), overnight. Subsequently, the reaction mixture ? been exposed to air, stirred for 12 hours, and the solvent ? been removed, under vacuum, obtaining a residue that ? was washed with saturated aqueous ammonium chloride (NH4Cl) solution (40 ml), filtered and washed again with saturated aqueous ammonium chloride (NH4Cl) solution (30 ml) and water (20 ml) to obtain a powder brown corresponding to Cr(Ie)Cl (753 mg, yield: 87.5%).

MALDI-TOF MS (DCTB): 683.1.

EXAMPLE 18

Synthesis of Cr(If)Cl

In a 100 ml double-necked flask, Salen (XVIf) obtained as reported in example 7 (1.21 mg, 1.70 mmol) and chromium(II) chloride (CrCl2) (251 mg, 2.04 mmol) , were dissolved in anhydrous tetrahydrofuran (THF) (20 ml) and stirred under argon, at room temperature (25°C), overnight. Subsequently, the reaction mixture ? been exposed to air, stirred for 12 hours, and the solvent ? been removed, under vacuum, obtaining a residue that ? was washed with saturated aqueous ammonium chloride (NH4Cl) solution (50 ml), filtered and washed again with saturated aqueous ammonium chloride (NH4Cl) (40 ml) and water (40 ml) solution to obtain a powder brown corresponding to Cr(If)Cl (1.08 g, yield: 79.7%).

MALDI-TOF MS (DCTB): 795.29.

EXAMPLE 19

Synthesis of Cr(Ig)Cl

In a 100 ml double-necked flask, Salen (XVIg) obtained as reported in example 3 (690 mg, 0.904 mmol) and chromium(II) chloride (CrCl2) (133 mg, 1.09 mmol), were dissolved in anhydrous tetrahydrofuran (THF) (20 ml) and stirred under argon, at room temperature (25°C), overnight. Subsequently, the reaction mixture ? been exposed to air, stirred for 12 hours, and the solvent ? been removed, under vacuum, obtaining a residue that ? was washed with saturated aqueous ammonium chloride (NH4Cl) solution (50 ml), filtered and washed again with saturated aqueous ammonium chloride (NH4Cl) (50 ml) and water (30 ml) solution to obtain a powder brown corresponding to Cr(Ig)Cl (676 mg, yield: 88%).

MALDI-TOF MS (DCTB): 847.1.

EXAMPLE 20

Synthesis of Cr(Ih)Cl

In a 100 ml double-necked flask, Salen (XVIh) obtained as reported in example 9 (620 mg, 0.708 mmol) and chromium(II) chloride (CrCl2) (104 mg, 0.850 mmol), were dissolved in tetrahydrofuran anhydrous (THF) (20 ml) and stirred under argon, at room temperature (25°C), overnight. Subsequently, the reaction mixture ? been exposed to air, stirred for 12 hours, and the solvent ? been removed, under vacuum, obtaining a residue that ? was washed with saturated aqueous ammonium chloride (NH4Cl) solution (40 ml), filtered and washed again with saturated aqueous ammonium chloride (NH4Cl) (40 ml) and water (30 ml) solution to obtain a powder brown corresponding to Cr(Ih)Cl (593 mg, yield: 87%).

MALDI-TOF MS (DCTB): 959.0.

EXAMPLE 21

Synthesis of Cr(Ik)Cl

In a 100 ml double-necked flask, Salen (XVIj) obtained as reported in the example 10 (690 mg, 0.842 mmol) and chromium(II) chloride (CrCl2) (124 mg, 1.01 mmol), were dissolved in anhydrous tetrahydrofuran (THF) (20 ml) and stirred under argon, at room temperature (25°C), overnight. Subsequently, the reaction mixture ? been exposed to air, stirred for 12 hours, and the solvent ? been removed, under vacuum, obtaining a residue that ? was washed with saturated aqueous ammonium chloride (NH4Cl) solution (50 ml), filtered and washed again with saturated aqueous ammonium chloride (NH4Cl) (40 ml) and water (40 ml) solution to obtain a powder brown corresponding to Cr(Ij)Cl (650 mg, yield: 85%).

MALDI-TOF MS (DCTB): 903.0.

EXAMPLE 22

Synthesis of Cr(Ik)Cl

In a 100 ml double-necked flask, Salen (XVIk) obtained as reported in example 11 (750 mg, 0.805 mmol) and chromium(II) chloride (CrCl2) (119 mg, 0.966 mmol), were dissolved in tetrahydrofuran anhydrous (THF) (20 ml) and stirred under argon, at room temperature (25°C), overnight. Subsequently, the reaction mixture ? been exposed to air, stirred for 12 hours, and the solvent ? been removed, under vacuum, obtaining a residue that ? was washed with saturated aqueous ammonium chloride (NH4Cl) solution (40 ml), filtered and washed again with saturated aqueous ammonium chloride (NH4Cl) (30 ml) and water (30 ml) solution to obtain a powder brown corresponding to Cr(Il)Cl (780 mg, yield: 95%).

MALDI-TOF MS (DCTB): 1015.2.

EXAMPLE 23

Synthesis of Cr(Im)Cl

In a 100 ml double-necked flask, Salen (XVIm) obtained as reported in example 12 (1.0 g, 1.60 mmol) and chromium(II) chloride (CrCl2) (300 mg, 2.44 mmol) , were dissolved in anhydrous tetrahydrofuran (THF) (20 ml) and stirred under argon, at room temperature (25°C), for 6 hours. Subsequently, ? ethyl acetate (50 ml) was added and the resulting reaction mixture was washed with saturated aqueous ammonium chloride (NH4Cl) solution (3 x 50 ml), dried over magnesium sulfate (MgSO4) and the solvent was removed, under vacuum, obtaining a dark brown powder corresponding to Cr(Im)Cl (1.07 g, yield: 94%).

HRMS (FAB) calculated for C40H54CrN4O2 [M<+>-Cl]: 674.3652; found: 674.3664.

EXAMPLE 24

Synthesis of Co(Im)]OAc

In a 100 ml double-necked flask, ? was added to a solution of Salen (XVIm) obtained as reported in example 12 (1.52 g, 2.43 mmol) in dichloromethane (CH2Cl2) (20 ml), a solution of cobalt acetate ([Co(OAc)2 ] (722 mg, 4.08 mmol) in methanol (10 ml): the resulting solution was stirred, under argon, at room temperature (25°C), for 6 hours.Then, the reaction mixture was exposed to The air was stirred for 3 hours, and the solvent was removed under vacuum, obtaining a residue which was redissolved in methanol (25 ml) and precipitated by slow addition of water.The resulting residue was washed with water (2 x 10 ml) and purified by dicalite filtration to obtain a brown powder corresponding to Co(Im)OAc (1.51 g, yield: 84%).

HRMS (FAB) calculated for C40H54CoN4O2: 681.3579; found: 681.3575.

EXAMPLE 25

Summary of Salen (XVIn)

In a 250 ml double-necked flask, a mixture of 3,5-di-tert-butyl-2hydroxybenzaldehyde (13) (4.23 g, 18.05 mmol) and 3,4-diaminobenzonitrile (35) (1, 20 g, 9.01 mmol) in methanol (50 ml) with a few drops of a glacial acetic acid, ? refluxed overnight. Subsequently, the reaction mixture ? been cooled to room temperature (25?C) obtaining a yellow solid that ? was recovered by filtration, washed with cold methanol (3 x 5 mL). The solid ? been subsequently dissolved with dichloromethane (CH2Cl2) (30 ml) and the solution obtained ? was washed with water (2x10 ml) obtaining an aqueous phase and an organic phase which were separated through a separating funnel. The organic phases obtained were combined, dried over magnesium sulphate (MgSO4) and the solvent ? was removed in vacuo, obtaining a yellow solid corresponding to Salen (XVIn) (2.62 g, yield: 51%). <1>H NMR (300 MHz, acetone-d6) ? 9.03 (d, J = 3.54 Hz, 1H), 8.99 (d, J = 3.92 Hz, 1H), 7.93 (t, J = 2.15, 2.15 Hz, 1H), 7.80 (dd, J = 1.8, 8.2 Hz, 1H ), 7.67 (dd, J = 2.6, 8.2 Hz, 1H), 7.55 (dd, J= 2.51, 4.77 Hz, 2H), 7.51 (dt, J = 2.10, 2.10, 4.14 Hz, 2H), 1.45 (s, 18H), 1.33 (s, 18H).

EXAMPLE 26

Summary of Salen (XVIp)

In a 250 ml double-necked flask, a mixture of 3,5-di-tert-butyl-2-hydroxybenzaldehyde (13) (9.46 g, 40.36 mmol) and 4-fluoro-1,2-phenylenediamine (36) (2.04 g, 16.14 mmol) in methanol (70 ml) with a few drops of glacial acetic acid, ? refluxed overnight. Subsequently, the reaction mixture ? been cooled to room temperature (25?C) obtaining a yellow solid that ? was recovered by filtration and washed with cold methanol (3 x 5 mL). Subsequently, the solid obtained ? been dissolved with dichloromethane (CH2Cl2) (30 ml) and the solution obtained? was washed with water (2 x 10 ml) obtaining an aqueous phase and an organic phase which were separated through a separating funnel. The organic phases obtained were combined, dried over magnesium sulphate (MgSO4) and the solvent ? was removed in vacuo, obtaining a yellow solid corresponding to Salen (XVIn) (2.12 g, yield: 24%).

<1>H NMR (300 MHz, acetone-d6) ? 8.97 (d, J= 3.53 Hz, 1H), 8.92 (d, J = 3.44 Hz, 1H), 7.55 (ddd, 1H), 7.53 (d, J = 2.44 Hz, 1H), 7.51 (d, J = 2.48 Hz, 1H), 7.49 (t, J = 2.20, 2.20 Hz, 1H), 7.46 (t, J = 2.18, 2.18 Hz, 1H), 7.37 (dt, J = 2.67, 2.67, 9.85 Hz, 1H), 7.19 (td, J = 2.86, 8.46, 8.53 Hz, 1H), 1.45 (d, J = 0.95 Hz, 18H), 1.33 (d, J = 1.99 Hz, 18H).

EXAMPLE 27

Summary of Salen (XVIp)

In a 250 ml double-necked flask, a mixture of 3,5-di-tert-butyl-2-hydroxybenzaldehyde (13) (2.35 g, 10.02 mmol) and 9,10-diaminophenanthrene (37) ( 1.04 g, 5.01 mmol) in methanol (70 ml) with a few drops of a glacial acetic acid ? refluxed overnight. Subsequently, the reaction mixture ? been cooled to room temperature (25?C) obtaining a yellow solid that ? was recovered by filtration and washed with cold methanol (3 x 5 mL). The solid ? been subsequently dissolved with dichloromethane (CH2Cl2) (30 ml) and the solution obtained ? was washed with water (2 x 10 ml) obtaining an aqueous phase and an organic phase which were separated through a separating funnel. The organic phases obtained were combined, dried over magnesium sulphate (MgSO4) and the solvent ? was removed in vacuo, obtaining a yellow solid corresponding to Salen (XVIq) (1.06 g, yield: 33%). <1>H NMR (300 MHz, acetone-d6) ? 8.94 (dd, J = 1.8, 7.5 Hz, 2H), 8.93 (s, 2H), 8.07 (dd, J = 1.8, 7.8 Hz, 3H), 7.77 (td, J = 1.3, 7.0 Hz, 2H), 7.72 (td, J = 1.3, 6.9 Hz, 2H), 7.50 (d, J = 2.50 Hz, 2H), 7.37 (d, J = 2.55 Hz, 2H), 1.43 (d, J = 1.0 Hz, 18H), 1.27 (d, J = 1.0Hz, 18H).

EXAMPLE 28

Synthesis of Cr(In)Cl

In a 100 ml double-necked flask, Salen (XVIn) obtained as reported in the example 25 (1.06 g, 1.87 mmol) and chromium(II) chloride (CrCl2) (0.34 g, 2.77 mmol), were dissolved in anhydrous tetrahydrofuran (THF) (20 ml) and stirred under argon, at room temperature (25°C), overnight and in air for 6 hours. Subsequently, ? been added diethyl ether (50 ml) and the reaction mixture obtained ? been washed with a saturated aqueous solution of ammonium chloride (NH4Cl) (3 x 100 ml), dried over magnesium sulphate (MgSO4) and the solvent ? been removed, under vacuum, obtaining a dark brown powder which? was crystallized from acetone (20 ml)/heptane (150 ml) obtaining Cr(In)Cl as brown crystals (1.04 g, yield: 86%).

HRMS (FAB) calculated for C37H45CrN3O2 [M<+>-Cl]: 615.2917; found: 615.2941.

EXAMPLE 29

Synthesis of Cr(In)Cl

In a 100 ml double-necked flask, Salen (XVIp) obtained as reported in the example 26 (1.50 g, 2.69 mmol) and chromium(II) chloride (CrCl2) (0.49 g, 4.03 mmol), were dissolved in anhydrous tetrahydrofuran (THF) (30 ml) and stirred under argon, at room temperature (25°C), overnight and in air for 6 hours. Subsequently, ? been added diethyl ether (70 ml) and the reaction mixture obtained ? been washed with a saturated aqueous solution of ammonium chloride (NH4Cl) (3 x 150 ml), dried over magnesium sulphate (MgSO4) and the solvent ? been removed, under vacuum, obtaining a dark brown powder which? was crystallized from acetone (30 ml)/heptane (200 ml) obtaining Cr(Ip)Cl as brown crystals (0.57 g, yield: 33%).

HRMS (FAB) calculated for C36H45CrFN2O2 [M<+>-Cl]: 608.2870; found: 608.2881.

EXAMPLE 30

Synthesis of Cr(Iq)Cl

In a 100 ml two-neck flask, Salen (XVIq) obtained as reported in example 27 (0.46 g, 0.72 mmol) and chromium(II) chloride (CrCl2) (0.13 g, 1.08 mmol), were dissolved in anhydrous tetrahydrofuran (THF) (15 ml) and stirred under argon, at room temperature (25°C), overnight and in air for 6 hours. Subsequently, ? been added diethyl ether (30 ml) and the reaction mixture obtained ? been washed with a saturated aqueous solution of ammonium chloride (NH4Cl) (3 x 70 ml), dried over magnesium sulphate (MgSO4) and the solvent ? been removed, under vacuum, obtaining a dark brown powder which? was crystallized from acetone (10 ml)/heptane (100 ml) obtaining Cr(Iq)Cl as brown crystals (0.38 g, yield: 72%).

HRMS (FAB) calculated for C44H50CrN2O2 [M<+>-Cl]: 690.3277; found: 690.3295.

Claims (3)

CLAIMS 1. Metal complex with salen-type ligand having general formula (I) or (II): in which: - R1 and R2, identical or different, represent a hydrogen atom; or are selected from C1-C20 linear or branched alkyl groups, saturated or unsaturated, preferably C1-C12, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups; - or R1, identical or different, represent a monovalent organic radical having the general formula (III): in which: - R3, R4 and R5, identical or different, represent a hydrogen atom; or are selected from C1-C20 linear or branched alkyl groups, saturated or unsaturated, preferably C1-C12, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups; - r, s and t, identical or different, are integers ranging from 0 to 5, preferably ranging from 0 to 2, provided that r s t varies from 1 to 5, preferably ranging from 1 to 3; - or R1 and R2 in the general formula (I), can be connected together to form, together with the other atoms to which they are connected, a saturated or unsaturated cycle or bicycle, which can? optionally being substituted with saturated or unsaturated linear or branched C1-C20 alkyl groups, optionally including heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups; - Z represents a divalent organic radical having the general formula (IV), (V), (VI), (VII), (VIII), (IX), (X), (XI) or (XII): in which: - R6 represents a hydrogen atom; or ? selected from linear or branched, saturated or unsaturated, C1-C20 alkyl groups, preferably C1-C12, optionally containing heteroatoms; - R7 represents a halogen atom such as fluorine, chlorine, bromine or iodine, preferably fluorine; either a cyano group, or a nitro group; or ? selected among linear or branched C1-C20 perfluoroalkyl groups, preferably saturated ? a trifluoromethyl group; - R8, identical or different, represent a hydrogen atom; or represent a halogen atom such as fluorine, chlorine, bromine or iodine, preferably fluorine; either a cyano group, or a nitro group; or are selected from saturated, linear or branched C1-C20 perfluoroalkyl groups, preferably a trifluoromethyl group, saturated or unsaturated, linear or branched C1-C20 alkyl groups, preferably C1-C12, optionally containing heteroatoms, optionally substituted aryl groups, heteroaryl groups optionally substituted, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups; - o Z represents a divalent organic radical having general formula (XIII) or (XIV): in which: - R9, R10, R11, R12, R13 and R14, identical or different, represent a hydrogen atom; or are selected from C1-C20 linear or branched alkyl groups, saturated or unsaturated, preferably C1-C12, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups; - either R9 and R10, or R9 and R12 in general formula (XIII), or R9 and R13, or R9 and R14 in general formula (XIV), can be connected together to form, together with the other atoms to which they are connected, a cycle saturated or unsaturated, which can? optionally be substituted with linear or branched C1C20 alkyl groups, saturated or unsaturated, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups, trialkyl- or triaryl-silyl groups, dialkyl groups or diarylamine, dialkyl- or diaryl phosphine groups, C1-C20 linear or branched alkoxy groups, saturated or unsaturated, preferably C2-C10, optionally substituted aryloxy groups, optionally substituted thioalkoxy or thioaryloxy groups, cyano groups, said cycle optionally containing heteroatoms such as oxygen, sulphur, nitrogen, silicon, phosphorus, selenium, preferably oxygen, nitrogen; provided that when Z represents a divalent organic radical having general formula (XIII) or (XIV), R1 represents a monovalent organic radical having general formula (III) or R1 and R2, may be linked together to form, together with the other atoms a which are connected, a cycle or bicycle saturated or unsaturated, which can? be optionally replaced with linear or branched C1-C20 alkyl groups, saturated or unsaturated, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups; - Z? represents a divalent organic radical having general formula (XIII) or (XIV) given above; - Y represents an oxygen atom, or a sulfur atom, or a selenium atom, or a tellurium atom, preferably an oxygen atom or a sulfur atom; or represents an imido group -N-R15, wherein R15 represents a hydrogen atom; or ? selected from C1-C20 linear or branched alkyl groups, saturated or unsaturated, preferably C1-C12, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted cycloalkyl groups; - X represents a halogen anion such as a fluoride anion, a chloride anion, a bromide anion, an iodide anion, preferably a chloride anion, a bromide anion; or ? selected from inorganic anions such as azide anion, hydroxide anion, amide anion, perchlorate anion, chlorate anion, sulfate anion, phosphate anion, nitrate anion, preferably an azide anion; or ? selected from organic anions such as carboxylate anion having general formula -OCOR16, alcoholate anion having general formula -OR16, thioalcoholate anion having general formula -SR16, alkyl amide anion having general formula -NHR16, dialkyl-amide anion having general formula -N(R16) 2, where R16 ? selected from C1-C20 linear or branched alkyl groups, saturated or unsaturated, preferably C1-C12, optionally containing heteroatoms, or ? selected from optionally substituted aryl groups or optionally substituted cycloalkyl groups; - M represents a metal atom selected from chromium, manganese, iron, cobalt, aluminium, preferably chromium, cobalt. 2. Salen-type binder having general formula (XV) or (XVI): in which: - R17, identical or different, represent a hydrogen atom; or they are selected from linear or branched, saturated or unsaturated C1-C6 alkyl groups, preferably C1-C2; more preferably, they are identical and represent a hydrogen atom or a methyl group; - R1 and R2, identical or different, represent a hydrogen atom; or are selected from C1-C20 linear or branched alkyl groups, saturated or unsaturated, preferably C1-C12, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups; - or R1, identical or different, represents a monovalent organic radical having the general formula (III): in which: - R3, R4 and R5, identical or different, represent a hydrogen atom; or are selected from C1-C20 linear or branched alkyl groups, saturated or unsaturated, preferably C1-C12, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups; - r, s and t, identical or different, are integers ranging from 0 to 5, preferably ranging from 0 to 2, provided that r s t varies from 1 to 5, preferably ranging from 1 to 3; - or R1 and R2 in the general formula (I), can be connected together to form, together with the other atoms to which they are connected, a saturated or unsaturated cycle or bicycle, which can? optionally being substituted with saturated or unsaturated linear or branched C1-C20 alkyl groups, optionally including heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups; - Z represents a divalent organic radical having the general formula (IV), (V), (VI), (VII), (VIII), (IX), (X), (XI) or (XII): in which: - R6 represents a hydrogen atom; or ? selected from linear or branched, saturated or unsaturated, C1-C20 alkyl groups, preferably C1-C12, optionally containing heteroatoms; - R7 represents a halogen atom such as fluorine, chlorine, bromine or iodine, preferably fluorine; either a cyano group, or a nitro group; or ? selected among linear or branched C1-C20 perfluoroalkyl groups, preferably saturated ? a trifluoromethyl group; - R8, identical or different, represent a hydrogen atom; or represent a halogen atom such as fluorine, chlorine, bromine or iodine, preferably fluorine; either a cyano group, or a nitro group; or are selected from saturated, linear or branched C1-C20 perfluoroalkyl groups, preferably a trifluoromethyl group, saturated or unsaturated, linear or branched C1-C20 alkyl groups, preferably C1-C12, optionally containing heteroatoms, optionally substituted aryl groups, heteroaryl groups optionally substituted, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups; - o Z represents a divalent organic radical having general formula (XIII) or (XIV): in which: - R9, R10, R11, R12, R13 and R14, identical or different, represent a hydrogen atom; or are selected from C1-C20 linear or branched alkyl groups, saturated or unsaturated, preferably C1-C12, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups; - either R9 and R10, or R9 and R12 in general formula (XIII), or R9 and R13, or R9 and R14 in general formula (XIV), can be connected together to form, together with the other atoms to which they are connected, a cycle saturated or unsaturated, which can? optionally be substituted with linear or branched C1-C20 alkyl groups, saturated or unsaturated, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups, trialkyl- or triaryl-silyl groups, dialkyl- or diarylamine, dialkyl- or diaryl phosphine groups, C1-C20 linear or branched alkoxy groups, saturated or unsaturated, preferably C2-C10, optionally substituted aryloxy groups, optionally substituted thioalkoxy or thioaryloxy groups, cyano groups, said cyclo optionally containing heteroatoms such as oxygen, sulfur, nitrogen, silicon, phosphorus, selenium, preferably oxygen, nitrogen; provided that when Z represents a divalent organic radical having general formula (XIII) or (XIV), R1 represents a monovalent organic radical having general formula (III) or R1 and R2, may be linked together to form, together with the other atoms a which are connected, a cycle or bicycle saturated or unsaturated, which can? be optionally replaced with linear or branched C1-C20 alkyl groups, saturated or unsaturated, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted heteroaryl groups, optionally substituted cycloalkyl groups, optionally substituted heterocyclic groups; - Z? represents a divalent organic radical having general formula (XIII) or (XIV) given above; - Y represents an oxygen atom, or a sulfur atom, or a selenium atom, or a tellurium atom, preferably an oxygen atom or a sulfur atom; or represents an imido group -N-R15, wherein R15 represents a hydrogen atom; or ? selected from C1-C20 linear or branched alkyl groups, saturated or unsaturated, preferably C1-C12, optionally containing heteroatoms, optionally substituted aryl groups, optionally substituted cycloalkyl groups; - X represents a halogen anion such as a fluoride anion, a chloride anion, a bromide anion, an iodide anion, preferably a chloride anion, a bromide anion; or ? selected from inorganic anions such as azide anion, hydroxide anion, amide anion, perchlorate anion, chlorate anion, sulfate anion, phosphate anion, nitrate anion, preferably an azide anion; or ? selected from organic anions such as carboxylate anion having general formula -OCOR16, alcoholate anion having general formula -OR16, thioalcoholate anion having general formula -SR16, alkyl amide anion having general formula -NHR16, dialkyl-amide anion having general formula -N(R16) 2, where R16 ? selected from C1-C20 linear or branched alkyl groups, saturated or unsaturated, preferably C1-C12, optionally containing heteroatoms, or ? selected from optionally substituted aryl groups or optionally substituted cycloalkyl groups; - M represents a metal atom selected from chromium, manganese, iron, cobalt, aluminium, preferably chromium, cobalt. 3. Use of a metal complex with a salen-type binder having general formula (I) or (II) according to claim 1, as a catalyst in a process for preparing polycarbonates.