PL233568B1 - Precursor of chelating carbene ligand, isomeric complexes containing the chelating ligand created from that precursor and their application as the catalyst of the metathesis of olefins - Google Patents

Abstract

The subject of the application is a precursor of a chelating carbene ligand represented by formula 1, where: R1, R2 and R3 are independently selected hydrogen atoms, hydrocarbon fragments, hydrocarbon fragments containing heteroatom(s); R4 and R5 are independently selected hydrogen atoms, hydrocarbon moieties, hydrocarbon moieties containing heteroatom(s), wherein R4 and R5 may (not) form a ring; R5 is a hydrocarbon moiety, a hydrocarbon moiety containing heteroatom(s); the term "hydrocarbon moiety" means a hydrocarbon substituent containing from 1 to about 64 carbon atoms, preferably 1 to about 32 carbon atoms, most preferably from 1 to about 16 carbon atoms, including linear, branched, cyclic, saturated and unsaturated chains, and the term "hydrocarbon moiety" "hydrocarbon containing a heteroatom" means a hydrocarbon fragment in which at least one of the carbon or hydrogen atoms is replaced anywhere by a heteroatom, a heteroatom being any atom in an organic molecule that is not a carbon or hydrogen atom, e.g. nitrogen, phosphorus, oxygen, sulfur, silicon. The application also covers the five- and six-membered isomer of the complex containing the chelating ligand formed from such a precursor, as well as the isomer, especially one in which M is ruthenium, as an olefin metathesis catalyst.

Description

Description of the invention

The present invention relates to a carbene chelating ligand precursor, isomeric complexes containing a chelating ligand formed from this precursor and their use as an olefin metathesis catalyst.

The olefin metathesis reaction is an important chemical tool for the formation of new double bonds between carbon atoms. New bindings are created, among others by cross-reaction (CM), ring closure (RCM) and ring opening polymerization (ROMP). The reaction is catalyzed by transition metal compounds and is widely used in industry. By metathesis, one obtains, inter alia, low molecular weight olefins ("Olefin Conversion Technology"), precursors of perfumes (Tonalide®) and antifungal agents (Terbinafine®), polymers based on cyclooctene (Vestenamer®), norbornene (Norsorex®) and dicyclopentadiene (Telene®, Pentem®, Metton®) . Thanks to the discovery of well-defined Grubbs-Hoveyda-type ruthenium catalysts, this reaction gained great popularity in the scientific community as well as found new applications in other industrial sectors. Currently, insecticides and pharmaceuticals obtained in this way are being implemented for mass production. Apart from the search for new applications for olefin metathesis, works related to the design of new catalysts are carried out in parallel. Currently, catalysts capable of being activated or deactivated on demand are of particular interest. Such a property will then allow the sale of ready-made preparations containing inactive catalyst, and then starting the metathesis reaction at any place and at any time. It is sufficient, for example, to heat the reaction mixture or to light it to start the reaction.

The temperature activated catalysts are obtained by using strongly chelating ligands. A strong bond, usually between ruthenium and nitrogen or sulfur, prevents the ligand from dissociating and thus initiating the reaction at room temperature. This process only takes place at elevated temperatures. The activation temperature (Ta) of the catalyst is usually determined by thermal analysis using ROMP reactions. Ruthenium catalysts showing this behavior have been described so far in a few scientific papers. Until now, as a chelating element, an imine group (Ta = 70-90 ° C; Slugovc et al., Organometallics, 2005, 24, 2255-2258), a quinoline ring (Ta = approx. 50-120 ° C; Gstrein et al., J. Polym. Sci A Polym. Chem., 2007, 45, 3494-3500), benzoquinoline (Ta = approx. 130 ° C; Pump et al., Organometallics, 2015, 34, 5383-5392) or phenylpyridinium (Ta = approx. 70 ° C; Szadkowska et al., Organometallics, 2010, 29, 117-124), and a thioether group (Ben-Asuly et al., Organometallics, 2008, 27, 811-813; Ben-Asuly et al., Organometallics, 2009, 28,4652-4655; Ginzburg et al., Organometallics, 2011, 30, 3430-3437). A research group led by Prof. Lemcoff observed that a catalyst having a thioether group can be activated in addition to temperature also with light (Ben-Asuly et al., Organometallics, 2009, 28, 4652-4655). The possibility of independent activation of the catalyst with different external stimuli has not been reported so far for complexes containing the nitrogen group; the literature examples only mention thermal (see above) or light activation (triazene group, Wang et al., Eur. J. Inorg. Chem., 2013, 5462-5468). Catalysts having chelating groups are also the subject of a number of inventions and patent applications.

The subject of US patent No. 8,846,938 B2 Method for preparation of ruthenium-based metathesis catalysts with chelating alkylidene ligands is a method of preparing O- and N-chelating ruthenium catalysts of the Hoveyda type. In one embodiment of the invention, the ruthenium center is nitrogen-chelated with an amino group that is part of an aromatic ring, namely quinolines.

The subject of US Patent No. 9,108,996 B2 Ruthenium-based metathesis catalysts and precursors for their preparation are amine precursors and their use in the synthesis of suitable ruthenium catalysts. In one embodiment of the invention, diarylamine derivatives are used as precursors. In yet another embodiment of the invention, the catalyst is used in an RCM reaction at 50 ° C.

The subject of US Patent No. 7,820,843 B2 Chelating carbene ligand precursors and their use in the synthesis of metathesis catalysts are ligand precursors containing various heteroatoms which are then used for the synthesis of ruthenium catalysts. In one embodiment of the invention, these precursors are aryloxy compounds. In another embodiment of the invention, the catalysts obtained by this method are shown to be active in the metathesis reaction at about room temperature.

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The subject of US Patent No. 8,871,879 B2 Latent, high-activity olefin metathesis catalysts containing an N-heterocyclic carbene ligand are ruthenium catalysts containing N-chelating ligands. In one embodiment of the invention, the ruthenium atom is chelated with an imino group. In another embodiment of the invention the RCM reaction is catalyzed at 60 ° C. In yet another embodiment of the invention, the ROMP reaction in the presence of a catalyst is started at 30 ° C.

The subject of the international patent application No. WO 2011091980 A1 Process for preparation of ruthenium-based carbene catalysts with chelating alkylidene ligands is a method of preparing ruthenium catalysts containing oxygen and sulfur groups. In one embodiment of the invention, 2-isopropoxystyrene is used as the ligand precursor.

The subject of the US patent application No. US 20140155511 A1 Sulfur chelated ruthenium compounds useful as olefin metathesis catalysts are ruthenium catalysts containing in their structure a sulfur atom chelating to ruthenium. In one embodiment of the invention, activation of the catalyst in a RCM reaction under the influence of temperature is shown. In yet another embodiment of the invention, activation of a catalyst in a ROMP reaction due to exposure to light has been demonstrated.

The present invention relates to a chelating carbene ligand precursor given by Formula 1

where:

R ¹ , R ² and R ³ are independently selected hydrogen atoms, hydrocarbon substituents, hydrocarbon substituents containing at least one heteroatom;

R ⁴ and R ⁵ are independently selected hydrogen atoms, hydrocarbon substituents, hydrocarbon substituents containing at least one heteroatom, wherein R ⁴ and R ⁵ may join to form a ring (not);

R ⁶ is a hydrocarbyl substituent, a hydrocarbyl substituent containing at least one heteroatom;

wherein the hydrocarbyl substituent may be linear, branched, cyclic, saturated and unsaturated and has from 1 to about 64 carbon atoms, preferably 1 to about 32 carbon atoms, most preferably from 1 to about 16 carbon atoms, and the hydrocarbon substituent contains at least one heteroatom represents a hydrocarbyl substituent in which at least one of the carbon or hydrogen atoms is replaced anywhere with a heteroatom, heteroatom being any atom in the organic molecule other than carbon or hydrogen, e.g. nitrogen, phosphorus, oxygen, sulfur, silicon. Preferably, R ^1, R ^2, and R ³ is hydrogen.

Preferably, a represents a delocalized carbon-carbon double bond.

Preferably, R ⁴ and R ⁵ form a benzene ring. Preferably, R ⁶ is a phenyl substituent.

The invention also relates to a five-membered isomer of a complex containing a chelating ligand formed from the precursor according to claims 1 to 5, given by formula 2

pattern 2

PL 233 568 Β1 where:

L ¹ is a neutral donor ligand dwuelektronowym selected from phosphines such as tricyckloheksylofosfina or N-heterocyclic carbene (NHC), preferably unsaturated ligand such as 1,3-bis- (2,4,6-trimethylphenyl) imidazolidin-2-ylidene (IMES) , most preferably 1,3-bis- (2,4,6-trimethylphenyl) imidazol-2-ylidene ligand (hLIMes);

X ¹ and X ² are anionic organic or inorganic ligands which may be the same or different and may be in cis or trans orientation with respect to the coordination center;

M is a Group 8 transition metal of the Periodic Table of the Elements, preferably ruthenium and a represents a single or multiple carbon-carbon bond.

Preferably, X ¹ and X ² are halogen, preferably chlorine atoms.

The invention also relates to a six-membered isomer of a complex containing a chelating ligand formed from the precursor according to claims 1 to 6, given by formula 3

formula 3 where:

L ¹ is a neutral donor ligand dwuelektronowym selected from phosphines such as tricyckloheksylofosfina or N-heterocyclic carbene (NHC), preferably unsaturated ligand such as 1,3-bis- (2,4,6-trimethylphenyl) imidazolidin-2-ylidene (IMES) , most preferably 1,3-bis- (2,4,6-trimethylphenyl) imidazol-2-ylidene ligand (HzIMes);

X ¹ and X ² are anionic organic or inorganic ligands which may be the same or different and may be in cis or trans orientation with respect to the coordination center;

M is a Group 8 transition metal of the Periodic Table of the Elements, preferably ruthenium and a represents a single or multiple carbon-carbon bond.

Preferably, X ¹ and X ² are halogen, preferably chlorine atoms.

The invention also relates to the use of an isomer according to claim 1. 6-7 and 8-9, especially one in which

M is ruthenium as a catalyst for olefin metathesis.

Summary of the invention

The present invention relates to a chelating ligand precursor and isomeric complexes containing such ligand. The complex containing the five-membered chelating ring is a kinetic isomer that transforms into a thermodynamically favored six-membered product in solution. The latter is characterized by high stability in the presence of air, both in solution and in a solid. It also has the characteristics of a so-called dormant catalyst, i.e. it is practically inactive under normal conditions, but capable of being activated by temperature or light.

Isomeric complexes containing the ligand of the invention are formed by the chemical reaction illustrated below:

PL 233 568 Β1

where:

L ¹

L ²

X ¹ and X ²

R ¹ , R ² and R ³

R ⁴ and R ⁵

R ⁶

is a two-electron neutral donor ligand selected from phosphines or N-heterocyclic carbenes (NHC);

is a neutral ligand selected from amines or phosphines; are anionic organic or inorganic ligands, can be the same or different, cis or trans orientation with respect to the coordination center;

are independently selected hydrogen atoms, hydrocarbon substituents, hydrocarbon substituents containing at least one heteroatom; Y ¹ and Y ² can join into a ring (not);

is a transition metal from Group 8 of the Periodic Table of the Elements; represents a single or multiple carbon-carbon bond;

are independently selected hydrogen atoms, hydrocarbon substituents, hydrocarbon substituents containing at least one heteroatom;

are independently selected hydrogen atoms, hydrocarbon substituents, hydrocarbon substituents containing at least one heteroatom; R ⁴ and R ⁵ can join to form a ring (not);

is a hydrocarbyl substituent, a hydrocarbyl substituent containing at least one heteroatom.

The term "hydrocarbyl substituent" denotes a hydrocarbon substituent containing from 1 to about 64 carbon atoms, preferably 1 to about 32 carbon atoms, most preferably from 1 to about 16 carbon atoms, including linear, branched, cyclic, saturated and unsaturated chains. A "heteroatom-containing hydrocarbon substituent" means a hydrocarbon substituent in which at least one of the carbon or hydrogen atoms is replaced at any point with a heteroatom. A heteroatom is defined as any atom in an organic molecule that is not carbon or hydrogen, e.g. nitrogen, phosphorus, oxygen, sulfur, silicon.

Preferably, L ¹ is an unsaturated ligand 1,3-bis- (2,4,6-trimethylphenyl) imidazolidin-2-ylideneowym (IMES), the ligand is most preferably 1,3-bis- (2,4,6-trimethylphenyl) -imidazol-2-ylidene (H ₂ IMes).

Preferably, L ² is pyridine, most preferably tricyclohexylphosphine.

Preferably, X ¹ and X ² are halides, most preferably chlorides.

Preferably, R ^1, R ^2, and R ³ is hydrogen.

Preferably, Y ¹ is hydrogen and Y ² is a phenyl substituent.

Preferably, M is ruthenium.

Preferably, a represents a delocalized carbon-carbon double bond.

Preferably, R ⁴ and R ⁵ form a benzene ring.

Preferably, R ⁶ is a phenyl substituent.

According to the invention, the chelating ligand precursor has an olefin and an azo group (-N = N-) separated from each other by two carbon atoms linked and is selected from the group consisting of compounds given by Formula 1.

Preparation of the chelating ligand precursor of the invention.

Preferably, the chelating ligand precursor is obtained by reacting nitrosobenzene with the appropriate aniline derivative.

Preferably, the reaction is carried out in the range of 0 ° -85 ° C, most preferably at room temperature.

Preferably, glacial acetic acid is used as the solvent.

Preferably, the solvent is added to the mixture of nitrosobenzene and 2-vinylanaline.

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Preferably, twice the excess of nitrosobenzene is used.

Preferably, mixing is for 0.25 to 48 hours, most preferably for one day.

Preferably, the compound is separated from the reaction mixture using chromatography.

Preferably, hydrocarbon solvents are used as eluent, more preferably n-hexane, most preferably pentane.

The ruthenium catalyst containing the chelating ligand according to the invention is obtained by reacting a precursor of such ligand with a ruthenium complex selected from the group consisting of compounds given by Formula 4 (commercially available).

pattern 4

Preparation of an isomer of a five-membered complex containing a chelating ligand of the invention.

The five-membered isomer given by Formula 2 is formed in a preferred temperature range of 0 ° - (- 60) ° C, more preferably at -10 ° C, most preferably at about 0 ° C.

Preferably, halogenated hydrocarbon solvents are used as the reaction medium, most preferably methylene chloride.

Preferably, the reaction is carried out in the presence of copper (I) chloride as a phosphine scavenger.

Preferably, the substrates are used in stoichiometric amounts.

Preferably, the reaction time is from 15 minutes to 2 hours, most preferably half an hour.

Preferably, the isomerically pure product is obtained by crystallization at -30 ° C.

Preferably, the five-membered isomer is stored in a crystalline form at 4 ° C in a dark place.

Preparation of an isomer of a six-membered complex containing a chelating ligand of the invention.

The six-membered isomer given by Formula 3 is formed in the preferred temperature range of 20 ° -80 ° C, more preferably at 20 ° -60 ° C, most preferably at about room temperature.

Preferably, the solvent is halogenated hydrocarbon solvents, most preferably methylene chloride.

Preferably, the reaction is carried out in the presence of copper (I) chloride as a phosphine binder.

Preferably, the substrates are used in stoichiometric amounts.

Preferably, the reaction takes from 2 to 24 hours, more preferably from 4 to 12, most preferably about 6 hours.

Preferably, the product is isolated by chromatography, most preferably followed by a crystallization performed from a pentane-methylene chloride solvent mixture.

Preferably, the six-membered isomer is stored in a crystalline form at 4 ° C in a dark place.

Properties and use of the complex containing the chelating ligand of the invention.

A complex, especially a ruthenium - that is, one in which M is ruthenium, containing a six-membered chelating ring shows catalytic properties in olefin metathesis reactions, preferably RCM reaction, most preferably ROMP reaction.

Preferably, the activation of the complex is by irradiation, most preferably by heating the reaction mixture.

Preferably, light activation is used for the ROMP reaction.

Preferably, the amount of catalyst used is 0.1-5 mol%, more preferably 0.2-1 mol%, most preferably 0.3 mol%.

Preferably, the monomer used is 5-norbornene-2,3-dicarboxylic acid diethyl ester.

Preferably, substituted or unsubstituted hydrocarbon solvents are used as the solvents, most preferably toluene.

Preferably, wavelengths below 320 nm are used, most preferably - 254 nm.

PL 233 568 B1

Preferably, the lamp power is in the range of 1-100 W, most preferably 4 W.

Preferably, the polymerization reaction time is from 1 to 48 hours, most preferably 24 hours.

Preferably, the polymer is extracted from the reaction mixture by precipitation with a polar solvent, most preferably methanol.

In another embodiment of the invention, elevated temperature is used to activate the catalyst.

Preferably, the reaction is carried out in the range 80 ° -160 ° C, preferably 100 ° -120 ° C, most preferably at a temperature of 110 ° C.

Preferably, the thermal activation of the catalyst is used in RCM reactions, most preferably ROMP reactions.

Preferably W, W-diallyl-p-tosylamide is used as the RCM substrate.

Preferably, 5-norbornene-2,3-dicarboxylic acid diethyl ester is used as the ROMP substrate.

Preferably, 1 mol% of catalyst is used for the RCM reaction, and 0.3 mol% for the ROMP reaction.

Preferably, the amount of catalyst used in the ROMP reaction is 0.1-5 mol%, more preferably 0.2-1 mol%, most preferably 0.3 mol%.

Preferably, the solvents are high boiling hydrocarbons, most preferably toluene.

Preferably, the RCM reaction is run for 2 to 144 hours, more preferably 6 to 48 hours, most preferably 24 hours.

Preferably, the ROMP reaction is performed for 15 minutes to 4 hours, more preferably for 0.5 to 2 hours, most preferably for one hour.

Preferably, the RCM product is purified by liquid chromatography.

Preferably, the ROMP product is purified by precipitation from the reaction mixture, most preferably with methanol.

Detailed description of the invention

The invention will now be illustrated in more detail in the preferred embodiments with reference to the accompanying drawings in which:

Fig. 1. Shows the absorbance spectra of the ruthenium complex isomeric complex containing the chelating ligand according to example 6.

Fig. 2. Illustrates the differential thermal analysis of the monomer-catalyst system according to Example 7.

Experimental part

Materials and equipment

Chemical reagents were purchased from Sigma-Aldrich, Apeiron Synthesis and Fluorochem; quality solvents p.a. from Merck, ChemPur and Poch. Solvents and glass for NMR measurements were purchased from Armar Chemicals.

Preparative column chromatography was performed using Kieselgel 60, 230-400 mesh silica gel (Merck). NMR spectra were made on Bruker 400 and 600 MHz instruments. Mass spectra were recorded on a Waters Maldi SYNAPT G2-S HDMS instrument. A handy Benda UV lamp (254 nm, 4W) was used in the photochemical experiments. DTA measurements were performed on an SDT-Q600 analyzer.

Preferred Embodiments of the Invention

Example 1 - Synthesis of a chelating ligand (AST) precursor

The ligand was synthesized according to a modified literature method (Shirtcliff et al., J. Org. Chem., 2004, 69, 6979-6985). Glacial acetic acid (6 ml) was added to 2-vinyl aniline (238 mg, 2 mmol) and nitrosobenzene (428 mg, 4 mmol) and stirred at room temperature under argon for 16 hours. The color of the solution changed from green to brown during the reaction. The reaction mixture was diluted with brine and the crude product was extracted with ethyl acetate. The extract was concentrated on a rotary evaporator and the residue was purified by column chromatography using petroleum ether as eluent. The product was isolated in a yield of 20% (84 mg) as a dark orange oil which solidifies in the refrigerator. 1 H NMR (400 MHz, CDCl 3) δ 7.97 (d, J = 7.5 Hz, 2H), 7.84 (dd, J = 17.7, 11.1 Hz, 1H), 7.73 (dd , J = 20.0, 8.0 Hz, 2H), 7.72 - 7.42 (m, 4H), 7.37 (t, J = 7.6 Hz, 1H), 5.89 (d, J = 17.7 Hz, 1H), 5.48 (d, J = 11.1 Hz, 1H). ^13C NMR (100 MHz, CDCl3): δ 153.1, 149.2, 136.9, 132.6, 131.1, 131.1, 129.2, 128.4, 126.1, 123.2 , 116.3, 115.7. HRMS (ASAP): m / z: calcd for C13H13N2: 209.1079 [M + H] +; found: 209.1074.

PL 233 568 Β1

The synthesis product of Example 1 is represented by the following structural formula. This is a special case of the relationship given generally by formula 1.

Example 2 - Synthesis of a ruthenium complex containing a five-membered chelating ring (CASH)

A dry Schlenk flask containing 2nd generation Grubbs complex (122mg, 0.144mmol), AST (30mg, 0.144mmol) and copper (I) chloride (14mg, 0.144mmol) was emptied and purged with argon three times, then placed in a bath with ice filled with water. Cold methylene chloride (1 mL) was added via a syringe to the flask and the resulting solution was stirred for 30 minutes at 0 ° C. The supernatant solution was carefully transferred by cannula into a small glass vial placed inside a larger vial filled with chilled pentane. The larger vial was sealed and placed in a refrigerator (-30 ° C) overnight. Brown CAST1 crystals were collected and analyzed by NMR and MS. According to ¹ H NMR CAST1 contains small amounts CAST2 due to rapid isomerization in solution. ¹ H NMR (600 MHz, methylene chloride-d 2, 10 ° C): 517.14 (s, 1H), 7.80 - 7.73 (m, 2H), 7.64 (d, J = 8.1 Hz, 1H), 7.57 (td, J = 7.6, 1.3 Hz, 1H), 7.51-7.47 (m, 1H), 7.32 (td, J = 7.4, 1.2 Hz, 1H), 7.16 (t, J = 7.9 Hz, 2H), 7.16 - 6.95 (m, 4H), 6.95 (dd, J = 7.6, 1 , 3 Hz, 1H), 4.12 - 3.85 (m, 4H), 2.46 (s, 12H), 2.33 (s, 6H). ¹³ C NMR (150 MHz, methylene chloride-d ₂ , 10 ° C): 5298.9, 208.0, 156.2, 152.4, 148.1, 138.6 (m), 137.7 (m ), 134.1, 130.4, 130.1, 129.8, 129.0, 120.8, 119.8, 117.9, 52.0, 21.2, 19.7, 18.2. HRMS (ESI): m / z: calcd for C8NN2N2BRuNa: 695.1258 [M + Na] ⁺ ; found: 695.1246.

The synthesis product of Example 2 shows the following structural formula. This is a special case of the relationship given generally by formula 2.

Example 3 - Synthesis of a ruthenium complex containing a six-membered chelating ring (CAST2)

A dry Schlenk flask containing 2nd generation Grubbs complex (122 mg, 0.144 mmol), AST (30 mg, 0.144 mmol) and copper (I) chloride (14 mg, 0.144 mmol) was emptied and filled with argon three times. Methylene chloride (5 mL) was added via a syringe to the flask and the resulting solution was stirred at room temperature for 6 hours. The reaction mixture was then concentrated in vacuo and the residue was chromatographed (petroleum ether: ethyl acetate = 7: 3) to give CAST2 as microcrystalline powder. CAST2 was recrystallized in 67% yield from pentane-methylene chloride solution. ¹ H NMR (600 MHz, methylene chloride-d 2, 20 ° C): 517.83 (s, 1H), 8.13 (dd, J = 7.8, 1.2 Hz, 1H), 7.95 ( td, J = 7.6, 1.4 Hz, 1H), 7.78 - 7.72 (m, 2H), 7.65 (td, J = 7.5, 1.3 Hz, 1H), 7 , 52 - 7.44 (m, 1H), 7.26 (dd, J = 8.5, 7.3 Hz, 2H), 7.18 (s, 4H), 6.82 (dd, J = 7 , 8, 1.4 Hz, 1H), 4.26-4.05 (m, 4H), 2.55 (s, 12H), 2.42 (s, 6H). ¹³ C NMR (150 MHz, methylene chloride-d2, 20 ° C): 5309.6, 211.6, 155.8, 142.6, 140.0 (m), 139.4, 138.3 (m) , 135.1 (m), 134.1, 131.2, 131.0, 130.2, 129.1, 126.6, 122.6, 122.1, 52.8, 51.6, 21, 5, 20.3, 18.5. HRMS (ESI): m / z: calcd for C8NN2N2BRuNa: 695.1258 [M + Na] ⁺ ; found: 695.1248.

The synthesis product of Example 3 shows the following structural formula. It is a special case of the relationship given generally by formula 3.

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Example 4 - Light initiated ROMP reaction

5-norbornene-2,3-dicarboxylic acid diethyl ester (21.3 mg, 89.2 μπιοΙ, 100 eq.), CAST2 (0.60 mg, 0.89 μπιοΙ, 1 eq.) Was added to the NMR tube made of quartz. ) and toluene-ds (700 μί). The solution was degassed by freezing in liquid nitrogen, then placed in front of a UV lamp and irradiated. The progress of the reaction was monitored by ¹ H NMR analysis, which showed 68% conversion after 24 hours.

Example 5 - Temperature-initiated ROMP reaction

5-norbornene-2,3-dicarboxylic acid diethyl ester (23.4 mg, 98.1 μπιοΙ, 300 eq.), CAST2 (0.22 mg, 0.33 μπιοΙ, 1 eq.) And toluene were added to the NMR tube. -ds (700 μί). The solution was degassed by freezing in liquid nitrogen and then placed in a 110 ° C bath. The progress of the reaction was monitored by ¹ H NMR analysis which showed a conversion of greater than 99% after one hour.

Example 5 - Temperature-initiated RCM reaction

To the NMR tube, / V, / V-diallyl-p-tosylamide (10.0 mg, 40.0 μπιοΙ, 100 eq.), CAST2 (0.27 mg, 0.40 μπιοΙ, 1 eq.) And toluene ds (700 μί). The solution was degassed by freezing in liquid nitrogen and then placed in a 110 ° C bath. The progress of the reaction was monitored by ¹ H NMR analysis, which showed 75% conversion after one day.

Example 6 - Study of the conversion of CAST1 to CAST2 by UV-Vis spectroscopy

CAST1 solution ⁽⁵ M 3Ί0-, toluene) in quartz cuvette provided with a handle spectroscope and a spectrum was recorded at room temperature at five minutes intervals. Fig. 1 shows the initial (CAST1) and final (CAST2) absorbance spectra.

Example 7 - Determination of the activation temperature of the CAST2 catalyst

CAST2 (1.0 mg, 1.5 μπιοΙ, 1 eq.) Was dissolved in methylene chloride (200 μί) and then 5-norbornene-2,3-dicarboxylic acid diethyl ester (177 mg, 750 μπιοΙ, 500 eq.) Was added. ). The solution was concentrated in vacuo and the residue placed in a Differential Scanning Calorimetry (DSC) pan. The mixture was heated at 3 ° C / min under argon. Fig. 2 shows the temperature difference of the test sample with the reference sample with increasing temperature (DTA profile). The exothermic peak at 100 ° C indicates the start of the polymerization reaction and therefore the catalyst activation temperature.

Claims (10)

Patent claims 1. A precursor of a chelating carbene ligand given by formula 1 formula 1 where: R ¹ , R ² and R ³ are independently selected hydrogen atoms, hydrocarbon substituents, hydrocarbon substituents containing at least one heteroatom; R ⁴ and R ⁵ are independently selected hydrogen atoms, hydrocarbon substituents, hydrocarbon substituents containing at least one heteroatom, wherein R ⁴ and R ⁵ may join to form a ring (not); PL 233 568 Β1 2. 3. 4. 5. 6. 7. 8. R ⁶ is a hydrocarbyl substituent, a hydrocarbyl substituent containing at least one heteroatom; wherein the hydrocarbyl substituent may be linear, branched, cyclic, saturated and unsaturated and has from 1 to about 64 carbon atoms, preferably 1 to about 32 carbon atoms, most preferably from 1 to about 16 carbon atoms, and the hydrocarbon substituent contains at least one heteroatom represents a hydrocarbyl substituent in which at least one of the carbon or hydrogen atoms is replaced anywhere with a heteroatom, heteroatom being any atom in the organic molecule other than carbon or hydrogen, e.g. nitrogen, phosphorus, oxygen, sulfur, silicon. The precursor according to Claim The process of claim 1, wherein R ¹ , R ² and R ³ is hydrogen. The precursor according to Claim The method of claim 1 or 2, wherein a represents a delocalized carbon-carbon double bond. The precursor according to Claim 3. A process according to claim 1, 2 or 3, characterized in that R ⁴ and R ⁵ form a benzene ring. The precursor according to any one of the preceding claims 1-4, characterized in that R ⁶ is a phenyl substituent. A five-membered isomer of a complex containing a chelating ligand formed from a precursor as defined in claims 1 to 5, given by the formula 2 χ! ^ 1 ¹ R ³ Χ ^^ Κ-R ⁴ N- ( ^a r ⁶ -n ^{from r5} formula 2 where: L ¹ is a neutral donor ligand dwuelektronowym selected from phosphines such as tricyckloheksylofosfina or N-heterocyclic carbene (NHC), preferably unsaturated ligand such as 1,3-bis- (2,4,6-trimethylphenyl) imidazolidin-2-ylidene (IMES) , most preferably 1,3-bis- (2,4,6-trimethylphenyl) imidazol-2-ylidene ligand (hhlMes); X ^{1 and} X ² are anionic organic or inorganic ligands which may be the same or different and may be in cis or trans orientation with respect to the coordination center; M is a Group 8 transition metal of the Periodic Table of the Elements, preferably ruthenium and a represents a single or multiple carbon-carbon bond. An isomer according to claim 6, characterized in that X ^{1 and} X ² are halogen, preferably chlorine atoms. A six-membered isomer of a complex comprising a chelating ligand formed from the precursor according to claims 1 to 6 given by formula 3 1 'l ¹ R ³ χί I, ^R χζΧ ^{Μ =} \ n' ^ ^r4 R ⁶ ^ 'ΝΑ' * R ⁵ formula 3 where: L ¹ is a neutral donor ligand dwuelektronowym selected from phosphines such as tricyckloheksylofosfina or N-heterocyclic carbene (NHC), preferably unsaturated ligand such as 1,3-bis- (2,4,6-trimethylphenyl) imidazolidin-2-ylidene (IMES) , most preferably 1,3-bis- (2,4,6-trimethylphenyl) imidazol-2-ylidene ligand (H 2 1Mes); X ^{1 and} X ² are anionic organic or inorganic ligands which may be the same or different and may be in cis or trans orientation with respect to the coordination center; PL 233 568 Β1 M is a Group 8 transition metal of the Periodic Table of the Elements, preferably ruthenium and a represents a single or multiple carbon-carbon bond. 9. The isomer according to claim 8, characterized in that X ^{1 and} X ² are halogen, preferably chlorine atoms. 10. The use of an isomer according to claim 1 6-7 and 8-9, especially one in which M is ruthenium, as olefin metathesis catalyst.