MX2008006404A - Catalytic process for the oligomerization of olefinic monomers - Google Patents

Abstract

A process for the simultaneous trimerization and tetramerization of olefinic monomers , wherein the process comprises contacting at least one olefinic monomer with catalyst system comprising:a) a source of chromium, molybdenum or tungsten;b) a ligand having the general formula (I);(R1)2P-X-P (R1)m(R2)n wherein:X is a bridging group of the formula -N(R3)-, wherein R3is selected from hydrogen, a hydrocarbyl group, a substituted hydrocarbyl group, a heterohydrocarbyl group, a substituted heterohydrocarbyl group, a silyl group or derivative thereof;the R1groups are independently selected from an optionally substituted aromatic group bearing a polar substituent on at least one of the ortho-positions;and the R2groups are independently selected from hydrocarbyl, substituted hydrocarbyl, heterohydrocarbyl and substituted heterohydrocarbyl groups and c) a cocatalyst, at a pressure in the range of from below atmospheric to about 40 barg and at a temperature in the range of from about 0°C to about 120°C. The present invention further relates to a process for the simultaneous trimerization and tetramerization of ethylene to 1-hexene and 1-octene.

Description

CATALYTIC PROCESS FOR THE OLIGOMERIZATION OF OLEFINIC MONOMERS FIELD OF THE INVENTION The present invention relates to a process for the oligomerization of olefinic monomers. BACKGROUND OF THE INVENTION Efficient catalytic trimerization or tetramerization of olefinic monomers, such as trimerization and tetramerization of ethylene to 1-hexene and 1-octene, is an area of great interest for the production of olefinic trimers and tetramers of varying degrees of commercial value In particular, 1-hexene is a valuable comonomer for linear low density polyethylene (LLDPE) and 1-octene is valuable as a chemical intermediate in the production of plasticizing alcohols, fatty acids, detergent alcohol and additives. of lubricating oils as well as a valuable comonomer in the production of polymers such as polyethylene. 1-hexene and 1-octene can be produced by means of a conventional transition metal oligomerization process, although trimerization and tetramerization routes are preferred. Various catalytic systems have been described in the art for trimerization and tetramerization to 1-hexene. Several of these catalysts are based on chromium. US-A-5198563 (Philips) describes catalysts based on Ref.: 193065 chromium containing monodentate amine ligands useful for the trimerization of olefins. US-A-5968866 (Philips) discloses an ethylene oligomerization / trimerization process using a catalyst comprising a chromium complex containing an asymmetric tridentate coordinating phosphine, arsan or triband stiban ligand and an aluminoxane to produce alpha-olefins which are enriched in 1-hexene. US 5523507 (Philips) describes a catalyst based on a chromium source, a 2,5-dimethylpyrrole ligand and an aluminum alkyl activator for use in the trimerization of ethylene to 1-hexene. Chem. Commun., 2002, 8, 858-859 (BP), describes chromium complexes of ligands of the type Ar2PN (Me) PAr (Ar = ortho-methoxy-substituted aryl group) as a catalyst for the trimerization of ethylene. WO 02/04119 (BP) describes a catalyst for the trimerization of olefins comprising a source of chromium, molybdenum or tungsten, a ligand containing at least one phosphorus, arsenic or antimony atom linked to at least one hydrocarbyl group or heterohydrocarbyl having a polar substituent, but excluding the case where all of those polar substituents are phosphane, arsan or stiban groups, and optionally an activator. The ligand used in most of the examples is (2-methoxyphenyl) 2PN (Me) P (2-methoxyphenyl) 2. Although the catalysts described in the BP documents mentioned above have good selectivity for 1-hexene in the fraction e, a relatively high level of by-product formation is typically observed (e.g., Cio by-products). WO 2005/039758 (Shell) discloses a composition of a trimerization catalyst and a process for the trimerization of olefinic monomers using said catalyst composition. Recently, catalytic systems for the tetramerization of ethylene to 1-octene have been described. Several of these catalysts are based on chromium. WO 2004/056478 and WO 2004/056479 (Sasol) describe catalyst compositions and processes for the tetramerization of olefins. The catalyst compositions described in WO 2004/056478 comprise a transition metal and a heteroatomic ligand having the general formula (R) nA-BC (R) m wherein A and C are independently selected from a group comprising phosphorus, arsenic , antimony, oxygen, bismuth, sulfur, selenium, and nitrogen, and B is a linking group between A and C, and R is independently selected from any homo or heterohydrocarbyl group of which at least one R group is substituted with a substituent polar ynym are determined by means of the respective valence and oxidation state of A and / or C. The catalyst compositions described in WO 2004/056479 comprise a transition metal and a heteroatomic ligand having the general formula (R ') nA -BC (R ') m where A, B, C, n and m are as defined above, and R 'is independently selected from any homo or heterohydrocarbyl group. Example 16 of WO 2004/056478 describes a tetramerization reaction of ethylene using Cr (III) acetylacetoneate, (phenyl) 2 PN (isopropyl) P (2-methoxyphenyl) 2 in a ratio of 1: 2 mol / mol, and MAO , with an atomic ratio of 136: 1, at 45 ° C and 45 bar. gauge. However, the reaction produced a product composition with more than 24% of the products with more than 11 carbon atoms, based on the weight of all the products (9.0% by weight of Cn + liquids and 15.11% by weight of solids). WO 2004/056480 (Sasol) describes the tetramerization and tandem polymerization of ethylene Specifically, WO 2004/056480 describes a process for polymerizing olefins to produce branched polyolefins in the presence of a different polymerization catalyst and a different tetramerization catalyst, wherein the tetramerization catalyst produces 1-octene at a selectivity of greater than 30% and the 1-octene produced is incorporated at least partially into the polyolefin chain.

Although the tetramerization catalysts described in the Sasol documents mentioned above possess good selectivity for 1-octene in the C8 fraction, again, a relatively high level of by-product formation is observed. Typically, the byproduct consists of Ce compositions; however, only about 70 to 80% by weight of the composition of the byproduct C6 is 1-hexene, the remainder of the by-product Ce comprising compounds such as methylcyclopentane and methylenecyclopentane. The presence of these compositions of Ce by-products remaining, which have very little use or commercial value, is quite undesirable from both the economic point of view and from the point of view of product separation. It has now been found with surprise that the process of the present invention provides an efficient route for the trimerization and tetramerization of olefin monomers, in particular the selective production of 1-hexene and 1-octene from ethylene while reducing the level of formation of by-product, especially Cio byproducts (ie heavy waxes and / or polyethylene) and compositions / isomers of C other than 1-hexane. BRIEF DESCRIPTION OF THE INVENTION The present invention relates to a process for the simultaneous trimerization and tetramerization of olefinic monomers, wherein the process comprises contacting at least one olefinic monomer with a catalyst system comprising: a) a source of chrome; b) a ligand having the general formula (I); (R1) 2P-XP (R1) m (R2) n (I) wherein: X is a bridging group of the formula -N (R3) -, wherein R3 is selected from hydrogen, a hydrocarbyl group, a group substituted hydrocarbyl, a silyl group or derivative thereof; the R1 groups are independently selected from an optionally substituted aromatic group bearing a polar substituent in at least one of the ortho positions; and the R2 groups are independently selected from substituted or unsubstituted aromatic groups, including heteroaromatic groups, which do not contain a polar substituent at any of the ortho positions; with the proviso that m is 0 or 1, n is 1 or 2 and the total of m + n is 2; optionally, any of the groups R1 and R2 may be independently linked to one or more of each other or to the bridging group X to form a cyclic structure; and c) a cocatalyst, at a pressure in the range of below atmospheric to about 40 bars gauge and a temperature in the range of about 0 ° C to about 120 ° C. The present invention also relates to a process for the simultaneous trimerization and tetramerization of ethylene to 1-hexene and 1-octene with said catalyst system comprising (a), (b) and (c), and at the defined pressure and temperature above. DETAILED DESCRIPTION OF THE INVENTION As used herein, the term "trimerization" means the catalytic trimerization of an olefinic monomer to give a product composition enriched in the compound derived from the reaction of three of said olefinic monomers. The term trimerization includes the cases in which all the olefinic monomers in the feed stream are identical as well as the cases in which the feed stream contains two or more different olefinic monomers. In particular, the term "trimerization" when employed in connection with the trimerization of ethylene means trimerization of ethylene to form an alkene Cs, especially 1-hexene. The term "selective trimerization" when used in connection with the trimerization of ethylene means the amount of C6 fraction formed in the composition of the product. The term "1-hexene selectivity" when used in relation to ethylene trimerization means the amount of 1-hexene formed in the Ce fraction of the composition of the product. The overall yield of 1-hexene in the trimerization of Ethylene is the product of the "trimerization selectivity" multiplied by the "selectivity of 1-hexene". The term "tetramerization" means the catalytic tetramerization of an olefinic monomer to give a product composition enriched in the compound derived from the reaction of four of said olefinic monomers. The term "tetramerization" includes the cases in which all the olefinic monomers in the feed stream are identical as well as the cases in which the feed stream contains two or more different olefinic monomers. In particular, the term "tetramerization" when used in connection with the tetramerization of ethylene means the tetramerization of ethylene to form Cg-alkene, especially 1-octene. The term "tetramerization selectivity" when employed in relation to the tetramerization of ethylene means the amount of C8 fraction formed in the product composition. The term "1-octene selectivity" when used in relation to tetramerization of ethylene means the amount of 1-octene formed in the C8 fraction of the composition of the product. The overall yield of 1-octene in the tetramerization of ethylene is the product of the "tetramerization selectivity" multiplied by the "1-octene selectivity". The source of chromium, component (a), for the catalyst system of the process of the present invention may include simple inorganic or organic salts of chromium. Examples of simple inorganic or organic salts are halides, acetylacetonates, carboxylates, oxides, nitrates, sulfates and the like. Additional sources of chromium may also include coordination and organometallic complexes, for example chromium trichloride tris-tetrahydrofuran, (benzene) tricarbonylammonium complex, chromium hexacarbonyl, and the like. Preferably, the source of chromium, component (a), for the catalyst is selected from simple inorganic and organic salts of chromium, molybdenum or tungsten. In one embodiment of the present invention the source of chromium, component (a), for the catalyst system is a simple chromium inorganic or organic salt, which is soluble in a solvent such as those described in WO 02/04119. The chromium source may also include a mixture of any coation of simple inorganic salts, simple organic salts, coordination complexes and organometallic complexes. In a preferred embodiment herein, component (a) is a source of chromium (III). Preferred sources of chromium for use herein are simple inorganic and organic chromium salts and coordinating or organometallic chromium complexes. The most preferred sources of chromium for use herein are simple inorganic and organic chromium salts, such as salts of carboxylic acids, preferably alkanoic acid salts containing from 1 to 30 carbon atoms, salts of aliphatic beta-diketones and salts of beta-ketoesters (e.g., chromium (III) 2-ethylhexanoate, chromium (III) octanoate and chromium (III) acetylacetonate), and chromium halide salts, such as chromium trichloride, chromium trichloride complex tris-tetrahydrofuran, chromium tribromide, chromium trifluoride, and chromium triiodide. Specific examples of preferred sources of chromium for use herein are chromium (III) acetylacetonate, also referred to as tris (2,4-pentanedione), Cr (acac) 3, chromium trichloride, CrCl 3, and chromium trichloride tris complex. -tetrahydrofuran, CrCl3 (THF) 3.

The ligand of the catalyst system of the process of the present invention, component (b), is of the general formula (I); (R1) 2P-XP (R1) m (R2) n (I) wherein: X is a bridging group of the formula -N (R3) -, wherein R3 is selected from hydrogen, a hydrocarbyl group, a group substituted hydrocarbyl, a silyl group or derivative thereof; the R1 groups are independently selected from an optionally substituted aromatic group bearing a polar substituent in at least one of the ortho positions; and the R2 groups are independently selected from substituted or unsubstituted aromatic groups, including heteroaromatic groups, which do not contain a polar substituent in any of the ortho positions; with the proviso that m is 0 or 1, n is 1 or 2 and the total of m + n is 2; and optionally, any of the groups R1 and R2 can be independently linked to one or more of each other or to the bridging group X to form a cyclic structure. The bridging group X is of the formula -N (R3) -, where R3 is preferably a hydrocarbyl group, a substituted hydrocarbyl group, a silyl group or derivative thereof. Typically, R3 is selected from hydrogen or groups consisting of alkyl, substituted alkyl, aryl, substituted aryl, aryloxy, substituted aryloxy, alkenyl, substituted alkenyl, cycloalkyl, substituted cycloalkyl, silyl or derivatives thereof, and alkyl or aryl substituted with any of these substituents or an alkoxycarbonyl, carbonyloxy, alkoxy, aminocarbonyl, carbonylamino or dialkylamino group or a halogen or nitro group. More preferably R3 is an alkyl, substituted alkyl (including heterocyclic alkyl substituted with at least one heteroatom, such as N or 0, and alkyl groups substituted with a heteroatom or heteroatom group), cycloalkyl group, substituted cycloalkyl, substituted cyclic aryl, aryl substituted, aryloxy or substituted aryloxy. Examples of suitable R3 groups include C1-C15 alkyl groups, substituted C1-C15 alkyl groups, C2-C5 alkenyl groups, substituted C2-C alkenyl groups, C3-C15 cycloalkyl groups, substituted C3-C cycloalkyl groups , C5-C15 aromatic groups, substituted C5-C15 aromatic groups, C1-C15 alkoxy groups and substituted C1-C15 alkoxy groups. The most preferred R3 groups are the C1-C15 alkyl groups, which include both linear and branched alkyl groups; Suitable examples include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, pentyl groups, pentyl groups branched with alkyl, hexyl, hexyl groups branched with alkyl, heptyl, heptyl groups branched with alkyl, octyl, and branched octyl groups with alkyl.

Examples of suitable bridging groups include N (methyl) -, -N (ethyl) -, -N (propyl) -, -N (isopropyl) -, N (butyl) -, -N (t-butyl) -, - N (pentyl) -, - (hexyl) -, -N (2-ethylhexyl) -, -N (cyclohexyl) -, -N (1-cyclohexylethyl) -, -N (2-methylcyclohexyl) -, -N (benzyl) ) -, -N (phenyl) -, -N (2-octyl) -, -N (p-methoxyphenyl) -, -N (pt-butylphenyl) -, -N ((CH2) 3-N-morpholino), -N (Si (CH3) 3) -, -N (CH2CH2CH2Si (OMe) 3)) -, -N (decyl) -and -N (allyl) -. The term "hydrocarbyl" as used herein refers to a group containing only carbon and hydrogen atoms. The hydrocarbyl group can be a linear or branched, saturated or unsaturated alkyl, a non-aromatic ring or an aromatic ring. Unless stated otherwise, preferred hydrocarbyl groups for use herein are those containing from 1 to 20 carbon atoms. The term "substituted hydrocarbyl" as used herein refers to hydrocarbyl groups containing one or more inert heteroatom-containing functional groups. By "functional groups containing inert heteroatoms" it is understood that the functional groups do not interfere in any substantial degree with the trimerization and tetramerization process. The term "aromatic" as used herein is used, refers to a monocyclic or polycyclic, aromatic or heteroaromatic ring having from 5 to 14 ring atoms, optionally containing from 1 to 3 heteroatoms selected from N, 0 and S. Preferably, the aromatic groups are monocyclic or polycyclic aromatic rings, such as cyclopentadienyl (which may also include ferrocenyl groups), phenyl, naphthyl or anthracyl, Unless otherwise stated, the preferred aromatic groups are monocyclic or polycyclic aromatic rings having from 5 to 10 ring atoms, the most aromatic groups preferred are monocyclic aromatic rings containing from 5 to 6 carbon atoms, such as phenyl, cyclopentadienyl, and a more preferred aromatic group is a phenyl group. The term "substituted aromatic" as used herein means that the aromatic group can be substituted with one or more substituents. The term "ortho position" x when used in relation to substituents on the aromatic groups R1 and / or R2, it is understood that the substituent is in the ortho position in relation to the atom attached to the phosphorus atom. The substituents in the groups R1 and / or R2 may contain carbon atoms and / or heteroatoms. The substituents can be either polar or non-polar. Suitable substituents include hydrocarbyl groups which may be straight or branched chain, saturated or unsaturated, aromatic or non-aromatic. The hydrocarbyl substituents may optionally contain heteroatoms such as Si, S, N or 0. Suitable aromatic hydrocarbyl substituents include monocyclic and polycyclic aromatic groups, preferably with 5 to 10 carbon atoms in the ring, such as phenyl and C alquilo alkyl groups. -C4 phenyl Suitable non-aromatic hydrocarbyl substituents include branched alkyl or cycloalkyl groups, preferably with 1 to 10 carbon atoms, more preferably 1 to 4 carbon atoms. Other suitable substituents on the groups R1 and / or R2 include halides such as chloride, bromide and iodide, thiol, -OH, ^ O-, -S-A1, -CO-A1, -NH2, -NHA1, -NAXA2, - CO-NA ^ 2, -N02, = 0, in which A1 and A2, independently, are non-aromatic groups preferably having 1 to 10 carbon atoms, more preferably 1 to 4 carbon atoms, eg, methyl, ethyl, propyl and isopropyl. When the R1 and / or R2 groups of the ligand are substituted, the preferred substituents are hydrocarbyl groups. Particularly preferred hydrocarbyl substituents are C 1 -C 4 alkyl groups, preferably methyl, ethyl, propyl, isopropyl, butyl, isobutyl, more preferably methyl. In a ligand embodiment of the catalyst system of the process of the present invention, component (b), m is 1 and n is 1. In another embodiment of the ligand of the catalyst system of the process of the present invention, component (b) , m is 0 and n is 2. Typically, in the ligand of the catalyst system of the process of the present invention, component (b), m is 0 and n is 2. The Rl groups of the ligand of the catalyst system of the process of the present invention, component (b), are independently selected from optionally substituted aromatic groups, each bearing a polar substituent in at least one of the ortho positions. To avoid confusion, the phrase "bearing a polar substituent in at least one of the ortho positions" means that, in the same ligand, the group R1 is substituted with a polar substituent in one or both of its ortho positions. The term "optionally substituted" in relation to the groups R1 of the ligand of the catalyst system of the process of the present invention, component (b), which are independently selected from optionally substituted aromatic groups, each bearing a polar substituent in at least one of the ortho positions means that, in addition to the polar substituent in at least one of the ortho positions, the same group R1 may contain one or more substituents. Polar is defined by the IUPAC as an entity with a permanent electric dipole moment. Thus, as used herein, the term "polar substituents" means that it incorporates a permanent electric dipole moment. Polar substituents suitable for use herein include, but are not necessarily limited to, optionally branched C 1 -C 20 alkoxy groups, i.e., the R 1 and / or R 2 groups are substituted with a hydrocarbyl group connected through an oxygen atom. oxygen bridging; optionally substituted C5-C ?4 aryloxy groups, i.e. the groups R1 and / or R2 are substituted with an optionally substituted aromatic group connected through a hydrogen bridging atom; optionally C 1 -C 2 alkoxy (C 2 -C 2) alkyl optionally branched groups, ie, the groups R 1 and / or R 2 are substituted with a C 1 -C 20 hydrocarbyl group bearing a C 1 -C 20 alkoxy group; hydroxy; (di-) C 1 -C 6 alkylamino; nitro; C 1 -C 6 alkylsulfonyl; alkylthio; C 1 -C 6 alkyl groups; sulfate; heterocyclic groups, especially with at least one ring atom of N and / or O and tosyl groups Examples of suitable polar substituents include methoxy, ethoxy, isopropoxy, phenoxy, decyloxy, dodecyloxy, tetradecyloxy, hexadecyloxy, octadecyloxy, eicosanoxy, pentafluorophenoxy, trimethylsiloxy, dimethylamino, methylsulfonyl, tosyl, methoxymethyl, methylthiomethyl 1,3-oxazolyl , hydroxyl, amino, methoxymethyl, phosphino, arsino, stibino, sulfate, nitro and the like .. Preferably, the polar substituents on the R1 groups are independently selected from optionally branched C?-Co alkoxy groups, optionally substituted C5-C?? aryloxy groups , and alkyl groups C? -C20 alkoxy (C? -C20) optionally branched. More preferably, the polar substituents are independently selected from optionally branched C?-C2o alkoxy group, especially optionally branched Ci-Cß alkoxy groups such as, for example, methoxy, ethoxy or isopropoxy of which methoxy is a particularly preferred polar substituent; alternatively, optionally branched C?-C2o alkoxy groups, optionally branched such as optionally branched Cs-C2o alkoxy groups, for example decyloxy, dodecyloxy, tetradecyloxy, hexadecyloxy, octadecyloxy or eicosanoxy groups, of which eicosanoxy is preferred, may be preferred as polar substituents in order to increase the solubility of the ligand in organic media. In one embodiment, the group R1 is independently selected from substituted or unsubstituted aromatic groups bearing an optionally branched C?-C2o alkoxy group in at least one of the ortho positions, such as an o-anisyl group. It is preferred that the R1 groups of the ligand of the catalyst system of the process of the present invention, the component (b), are the same and that they bear the same number and type of polar substituent (s). It is particularly preferred that each of said groups R1 carries a polar substituent in only one of the ortho-available positions. The groups R2 of the ligand of the catalyst system of the process of the present invention, component (b) are independently selected from substituted or unsubstituted aromatic groups, including substituted or unsubstituted heteroaromatic groups, which do not contain a polar substituent in any of the ortho positions. . In one embodiment of the ligand of the catalyst system of the process of the present invention, the component (b), the R2 groups can be independently selected from a group comprising benzyl, phenyl, tolyl, xylyl, mesityl, biphenyl, naphthyl, anthracenyl groups, phenoxy, thlyloxy, thiophenyl, pyridyl, thiophenoxy, ferrocenyl and tetrahydrofuranyl, optionally substituted. In another embodiment of the ligand, said R2 groups can be independently selected from a group comprising phenyl, tolyl, biphenyl, naphthyl and thiophenyl groups, optionally substituted. In a further embodiment of the ligand of the catalyst system of the process of the present invention, said R2 groups are independently selected from optionally substituted phenyl groups which does not contain a polar substituent at any of the ortho positions, or alternatively, they do not contain any substituents at all. polar. Any polar substituent present in said R2 groups can be an electron donor. Said R2 groups may optionally contain a non-polar substituent. The IUPAC defines non-polar as an entity without a permanent electrical dipole moment. The non-polar substituents can be a methyl groupethyl, propyl, butyl, isopropyl, isobutyl, tertbutyl, pentyl, hexyl, cyclopentyl, 2-methylcyclohexyl, cyclohexyl, cyclopentadienyl, phenyl, bi-phenyl, naphthyl, tolyl, xylyl, mesityl, ethenyl, propenyl and benzyl, or the like. Preferably, the non-polar substituent is not an electron donor. In a specific embodiment of the ligand of the catalyst system of the process of the present invention, component (b), said group R2 is an unsubstituted phenyl group. Optionally, any of the groups R1 and R2 may be linked to one or more of them or to the bridging group X to form a catalytic structure. In particular, when n is 2 then the two groups R 2 can optionally be linked together to form a cyclic structure incorporating the phosphorus atom. In another embodiment of the present invention, one or both phosphorus atoms of the ligand of the catalyst system of the process of the present invention can be independently oxidized by S, Se, N or 0. Typically, none of the phosphorus atoms of the second ligands are oxidized by S, Se, N or 0. In a further embodiment of the present invention, the ligand of the catalyst system of the process of the present invention may optionally contain multiple units of (R1) 2P-XP (R1) m ( R2) n- Non-limiting examples of such ligands include ligands wherein the individual units are coupled via either one or more of the groups R1 or R2 or via the bridging group X. Typically, the ligand does not contain multiple units (R1) 2P-XP (R1) m (R2) n. Ligands according to formula (I) can be prepared using methods known to one of skill in the art or described in published literature. Examples of such compounds include: (2-methoxyphenyl) 2 PN (methyl) P (2-methoxyphenyl) (phenyl), (2-methoxyphenyl) 2 PN (methyl) P (phenyl) 2, (2-ethoxyphenyl) 2 PN (methyl) P (2-ethoxyphenyl) (phenyl), (2-ethoxyphenyl) 2 PN (methyl) P (phenyl) 2, (2-methoxyphenyl) (2-ethoxyphenyl) PN (methyl) P (2-methoxyphenyl) (phenyl), (2) -methoxyphenyl) (2-ethoxyphenyl) PN (methyl) P (phenyl) 2, (2-isopropoxyphenyl) 2P (methyl) P (2-isopropoxyphenyl) (phenyl), (2-isopropoxyphenyl) 2PN (methyl) P (phenyl) 2, (2-methoxyphenyl) 2 PN (methyl) P (methoxyphenyl) (3-methoxyphenyl), (2-methoxyphenyl) 2 P (methyl) P (3-methoxyphenyl) 2, (2-methoxyphenyl) 2 PN (methyl) P (2 -methoxyphenyl) (4-methoxyphenyl), (2-methoxyphenyl) 2 PN (methyl) P (4-methoxyphenyl) 2, (2-methoxyphenyl) 2 PN (methyl) P (2-methoxyphenyl) (4-fluorophenyl), (2- methoxyphenyl) 2 PN (methyl) P (4-fluorophenyl) 2, (2-methoxyphenyl) 2 PN (methyl) P (2-ethoxyphenyl) (4-fluorophenyl), (2-methoxyphenyl) 2 PN (methyl) P (2-methoxyphenyl) 2 (-dimethylamino-phenyl), (2-methoxyphenyl) 2PN (methyl) P (4-dimethylamino-f) enyl) 2, (2-methoxyphenyl) 2 PN (methyl) P (2-methoxyphenyl) (4- (4-methoxyphenyl) -phenyl), (2-methoxyphenyl) 2 PN (methyl) P (4- (4-methoxyphenyl) - phenyl) 2, (2-methoxyphenyl) 2 PN (methyl) P (2-methoxyphenyl) (4-dimethylamino-phenyl), (2-methoxyphenyl) 2 PN (methyl) P (4-dimethylamino-phenyl) 2, (2-methoxyphenyl) ) 2 PN (methyl) P (2-methoxyphenyl) (4- (4-methoxyphenyl) -phenyl), (2-methoxyphenyl) 2 PN (methyl) P (4- (4-methoxyphenyl) -phenyl) 2, (2-methoxyphenyl) ) 2 PN (methyl) P (2-methoxyphenyl) (o-ethylphenyl), (2-methoxyphenyl) 2 PN (methyl) P (o-ethylphenyl) 2, (2-methoxyphenyl) 2 PN (methyl) P (2-methoxyphenyl) ( 2-naphthyl), (2-methoxyphenyl) 2 PN (methyl) P (2-naphthyl) 2, (2-methoxyphenyl) 2 PN (methyl) P (2-methoxyphenyl) (p-biphenyl), (2-methoxyphenyl) 2 PN ( methyl) P (p-biphenyl) 2, (2-methoxyphenyl) 2 PN (methyl) P (2-methoxyphenyl) (p-methylphenyl), (2-methoxyphenyl) 2 PN (methyl) P (p-methylphenyl) 2, (2 -methoxyphenyl) 2 PN (methyl) P (2-methoxyphenyl) (2-thiophenyl), (2-methoxyphenyl) 2 PN (methyl) (2-thiophenyl) 2, (2-methoxyphenyl) 2 PN (methyl) P (2-methoxy? faith n? l) (m-methylphenyl), (2-methoxyphenyl) 2PN (methyl) P (m-methylphenyl) 2, (2-methoxyphenyl) 2PN (ethyl) P (2-methox? phenyl) (phenyl), (2) -methoxyphenyl) 2PN (ethyl) P (phenyl) 2, (2-methoxyphenyl) 2PN (propyl) P (2-methoxyphenyl) (phenyl), (2-methoxyphenyl) 2PN (propyl) P (phenyl) 2, (2-methoxyphenyl) 2PN (isopropyl) P (2-methoxyphenyl) (phenyl), (2-methoxyphenyl) 2PN (isopropyl) P (phenyl) 2, (2-methoxyphenyl) 2PN (butyl) P (2- methox? phenyl) (phenyl), (2-methox? feml) 2PN (but? l) P (phenol) 2, (2-methox? phenyl) 2 PN (t-butyl) P (2-methox? fem) (phenyl), (2-methoxyphenyl) 2PN (t-butyl) P (phenol) 2, (2-methoxyphenyl) 2PN (phenyl) P (2-methoxyphenyl) (phenyl), (2-methoxyphenyl) phenyl) 2PN (phenyl) P (phenyl) 2, (2-methoxyphenyl) 2PN (cyclohexyl) P (2-methoxyphenyl) (phenyl), (2-methoxyphenyl) 2PN (cyclohexyl) P (phenyl) 2, ( 2-methox? Phenyl) PN (1-cyclohexylethyl) P (2-methox? Phenyl) (phenyl), (2-methox? Phen? L) 2PN (lc? Clohex? Let? L) P (phenol) 2 (2-methoxyphenyl) 2PN (2-met? Lc? Clohex? L) P (2-methox? Phenyl) (phenyl), (2-methoxyphenyl) 2PN (2-met? Lc? Clohex? L) P (phenyl) 2, (2-methox? Feml) 2PN (decyl) P (2-methox? Phenyl) (phenyl), (2) -methoxyphenyl) 2PN (decyl) P (phenyl) 2, (2-methoxyphenyl) 2PN (allyl) P (2-methoxyphenyl) (phenyl), (2-methoxyphenyl) 2PN (allyl) P (phenyl) ) 2, (2-methoxyphenyl) 2 PN (p-methoxyphenyl) P (2-methoxyphenyl) (phenyl), (2-methoxyphenyl) 2 PN (p-methoxyphenyl) P (phenol) 2, (2-methoxyphenyl) 2PN (pt-butylphenyl) P (2-methoxyphenyl) (phenyl), (2-methoxyphenyl) 2PN (pt-butylphenyl) P (phenyl) 2, (2-methoxyphenyl) 2PN ((CH 2) 3-N-morpholino ) P (2-methoxyphenyl) (phenyl), (2-methoxyphenyl) 2PN ((CH2) 3-N-morpholino) P (phenyl), (2-methoxyphenyl) 2PN (Si (CH3) 3) P (2-methoxyphenyl) ) (phenyl), (2-methoxyphenyl) 2 PN (Si (CH 3) 3) P (phenyl) 2, (2-methoxyphenyl) 2 P (= Se) N (isopropyl) P (2-methoxyphenyl) (phenyl), (2) -methoxyphenyl) 2 P (= Se) N (isopropyl) P (phenyl) 2, (2-methoxyphenyl) 2 PN (benzyl) P (2-methoxyphenyl) (phenyl), (2-methoxyphenyl) 2 PN (benzyl) P (phenyl) 2, (2-methoxyphenyl) 2PN (1-cyclohexyl-ethyl) P (2-methoxyphenyl) (phenyl), (2-m) ethoxyphenyl) 2PN (1-cyclohexyl-ethyl) P (phenyl) 2, (2-methoxyphenyl) 2PN [CH2CH2CH2Si (0Me3) P (2-methoxyphenyl) (phenyl), (2-methoxyphenyl) 2PN [CH2CH2CH2Si (OMe3) P ( phenyl) 2, (2-methoxyphenyl) 2 PN (2-methylcyclohexyl) P (2-methoxyphenyl) (phenyl), (2-methoxyphenyl) 2 PN (2-methylcyclohexyl) P (phenyl) 2, (2-methoxyphenyl) 2 P (= S) N (isopropyl) P (2-methoxyphenyl) (phenyl), (2-methoxyphenyl) 2P (= S) N (isopropyl) P (phenyl) 2, (2-eicosanoxyphenyl) 2PN (methyl) P (2-eicosanophenyl) ) (phenyl), (2-eicosanoxyphenyl) 2 PN (methyl) P (phenyl) 2, (2-methoxyphenyl) (2-eicosanoxyphenyl) PN (methyl) P (phenyl) 2, (2-methoxyphenyl) (2-eicosanoxyphenyl) PN (methyl) P (2-eicosanoxyphenyl) (phenyl), (2-eicosanoxyphenyl) 2 PN (methyl) P (4-eicosanoxyphenyl) (phenyl), (2-methoxyphenyl) (2-eicosanoxyphenyl) PN (methyl) P (4 -eicosanoxyphenyl) (phenyl), (2-eicosanoxyphenyl) 2 PN (methyl) P (4-eicosanoxyphenyl) (phenyl) 2, (2-methoxyphenyl) (2-eicosanoxyphenyl) PN (methyl) P (4-eicosanoxyphenyl) 2, ( 2-eicosanoxyphenyl) 2 P (methyl) P (2-eicosanoxyphenyl) (4-e icosanoxyphenyl), (2-methoxyphenyl) (2-eicosanoxyphenyl) PN (methyl) P (2-eicosanoxyphenyl) (4-eicosanoxyphenyl), and the like. The cocatalyst, the component (c), can in principle be any compound or mixture of compounds that generates an active catalyst system with the source of chromium, the component (a), and the ligand, the component (b). Compounds which are suitable for use as a cocatalyst include organoaluminum compounds, organoboron compounds, organic salts, such as methylolithium bromide and methylmagnesium and inorganic acids and salts, such as tetrafluoroboric acid etherate, silver tetrafluoroborate, sodium hexafluoroantimonate and Similar . Particularly preferred cocatalysts are organoaluminum compounds. The organoaluminum compounds for use herein are those having the formula A1R43, wherein each R4 group is independently selected from C?-C30 alkyl (preferably C1-C12 alkyl), oxygen containing portions or halides, and compounds such as LiAlH4 and the like. Non-limiting examples of suitable organoaluminum compounds include trimethylaluminum (TMA), triethylaluminum (TEA), tri-n-butyl aluminum, triisobutylaluminum (TIBA), tri-n-octylaluminum, methylaluminum dichloride, ethylaluminum dichloride, dimethylaluminum chloride, diethylaluminum and aluminoxanes (also called alumoxanes). Mixtures of organoaluminum compounds are also suitable for use herein. In a preferred embodiment of the present, the cocatalyst is an aluminoxane cocatalyst. These aluminoxane cocatalysts can comprise any aluminoxane compound or a mixture of aluminoxane compounds. The aluminoxanes can be prepared by the controlled addition of water to an alkylaluminum compound, such as those mentioned above, or are commercially available. Non-limiting examples of suitable aluminoxanes include methyl aluminoxane (MAO), modified methyl aluminoxane (MMAO), tetreaisobutyl dialuminoxane (TIBAO), tetra-n-butyl dialuminoxane and tetra-n-octyl dialuminoxane. In this context it should be noted that the term "aluminoxane" as used herein in this specification includes commercially available aluminoxanes, which are derived from the corresponding trialkylaluminium by the addition of water and which may contain from 2 to 15% by weight, typically about 5% by weight. % by weight, but optionally approximately 10% by weight of aluminum. Other suitable cocatalysts include those mentioned in WO 02/04119, WO 2004/056478 and WO 2004/056479, the disclosures of which are hereby incorporated by reference in their entirety. The amount of cocatalyst in the catalyst system of the present invention is typically sufficient to provide a ratio in the range of 0.1 to 20,000, preferably 1 to 2000, more preferably 1 to 1000, more preferably 1 to 500, of aluminum or boron atoms per chromium atom. In a specific embodiment of the present invention, the catalyst system of the process of the present invention comprises: a) a source of chromium; b) a ligand having the general formula (I); (R1) 2 P-X-P (R2) 2 (I) wherein X, R1 and R2 are as defined above; and c) a cocatalyst. In another specific embodiment of the present invention, the catalyst system of the process of the present invention comprises: a) a source of chromium; b) a ligand having the general formula (I); (R1) 2 P-X-P (R1) (R2) (I) wherein X, R1 and R2 are as defined above; and c) a cocatalyst. The catalyst system of the process of the present invention can independently comprise more than one ligand as defined above. The amount of chromium, that is component (a), and the amount of ligand, component (b), may be present in the system in a molar ratio in the range of 100: 1 to 1: 100, preferably 10. : 1 A 1:10. More preferably, chromium, component (a), and ligand, component (b), are present in a molar ratio in the range of 3: 1 to 1: 3. More preferably, the amount of component (a) and the amount of component (b) are present in a molar ratio of 1: 0.9 to 1: 1.1. The three catalyst components of the catalyst system, (a), (b) and (c), can be added together simultaneously or sequentially in any order to provide an active catalyst. The three catalyst components of the catalyst system, (a), (b) and (c), can be contacted in the presence of any suitable solvent. Suitable solvents are known to those skilled in the art, suitable solvents can include any inert solvent that does not react with the cocatalyst component, such as saturated aliphatic, unsaturated aliphatic, aromatic, halogenated hydrocarbons and ionic liquids. Typical solvents include, but are not limited to, benzene, toluene, xylene, ethylbenzene, eumeno, propane, butane, pentane, heptane, decane, dodecane, tetradecane, methylcyclohexane, methylcyclopentane, cyclohexane, 1-hexene, 1-octene, and the like . Other examples of suitable solvents are those described in WO 02/04119, such as hydrocarbon solvents and polar solvents such as diethyl ether, tetrahydrofuran, acetonitrile and the like. In another embodiment of the present invention, the catalyst system of the process of the present invention is formed by the addition of the cocatalyst component, (c), to a catalyst precursor composition comprising components (a) and (b) . The catalyst system of the present invention can be prepared either in the presence (ie, "in situ") or absence of the olefinic monomer. The three catalyst components of the catalyst system, (a), (b) and (c), can be combined completely in the absence of the olefinic monomer, or the olefinic monomer can be included before contacting the components of the catalyst system, simultaneously with the components of the catalyst system or at any point in the process of contacting the catalyst components. The three components of the catalyst system, (a), (b) and (c), can be combined at a temperature in the range of -100 to 200 ° C, preferably 0 to 150 ° C, more preferably 20 to 100 ° C. ° C.

The catalyst system of the process of the present invention may be unsupported or supported on a support material. Examples of suitable support materials can be found in WO 02/04119, WO 2004/056478 and WO 2004/056479. Olefinic monomers suitable for use in the trimerization and tetramerization process of the present invention may be olefinic monomers, which may be converted to a trimer or tetramer. Suitable olefinic monomers include, but are not necessarily limited to, ethylene, propylene, C4-C24 alpha-olefins preferably C4-C2or optionally branched, C4-C4 internal, preferably C4-C20, branched, C4-C24 vinylidene olefins, preferably optionally branched C4-C20, cyclic olefins C4-C24, preferably C4-C2o optionally branched and C4-C24, preferably C4-C2o or optionally branched dienes, as well as C4-C24 functionalized olefins, preferably C-C2o or optionally branched. Examples of suitable olefinic monomers include, but are not necessarily limited to, linear alpha-olefins, such as ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1 -decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene and 1-eicosene; branched alpha-olefins such as 4-methylpent-l-ene and 2-ethyl-l-hexene; linear and branched internal olefins such as 2-butene; styrene; cyclohexene; norboreno and similar. Mixtures of olefinic monomers can also be used in the process of the present invention. Preferred olefinic monomers for use in the trimerization and tetramerization process of the present invention are propylene and ethylene. Ethylene is especially preferred. The catalyst and process system of the present invention are particularly useful for the simultaneous trimerization and tetramerization of ethylene to 1-hexene and 1-octene.

The trimerization and simultaneous tetramerization reaction can be carried out in the solution phase, suspension phase, gas phase or mass phase. When simultaneous trimerization and tetramerization is performed in the solution or suspension phase, you can employ a diluent or solvent, which is substantially inert under trimerization and tetramerization conditions. Suitable diluents or solvents which are aliphatic and aromatic hydrocarbons, halogenated hydrocarbons and olefins which are substantially inert under trimerization and tetramerization conditions, such as those described in WO 02/04119, WO 2004/056478 and WO 2004/056479 can be employed.

The trimerization and tetramerization process of the present invention can be carried out in any of several suitable reactors, which are well known to one skilled in the art. Typically the trimerization and tetramerization process of the present invention is carried out in a batch, semilot or continuous mode. The simultaneous trimerization and tetramerization process of the present invention can be carried out under the following range of reaction conditions. Typically, the temperature will be in the range of from about 0 ° C to about 120 ° C, preferably from about 10 ° C to about 110 ° C, more preferably from about 20 ° C to about 100 ° C, even more preferably from about 40 ° C to about 100 ° C. The process of the present invention can also be conveniently carried out at a temperature range from about 10 ° C to about 70 ° C. However, it may be commercially desirable to perform the process of the present invention at an elevated temperature, therefore, the process of the present invention is quite suitable to be applied at a temperature in the range of about 70 ° C to about 90 ° C. . The pressure range under which the process of the present invention can be performed is typically in the range of from below atmospheric pressure to about 40 bar. Gauge. Preferably, the pressure will be in the range of about 0.1 to about 40 bars gauge, more preferably from about 0.5 to about 38 bars gauge, especially in the range of about 1 to about 35 bar gauge. Temperatures and pressures other than those set forth above may also be employed, however, the reaction product will have an excess of heavy and / or solid by-products or an insignificant amount of the trimer or tetramer. By varying the temperature and pressure it is possible that the ratio of trimers to tetramers produced in the process of the present invention varies. The amount of trimers produced in the process of the present invention typically increases with increasing temperature. The amount of tetramers produced in the process of the present invention typically increases with increasing temperature. The amount of heavy byproducts (C? 2+) and / or solids also seems to increase with increasing process pressure for the simultaneous trimerization and tetramerization of ethylene to 1-hexene and 1-octene. The amount of by-products seems to decrease with the increase in temperature, although the amount of the tetramer produced also seems to decrease with the increase in temperature. Therefore, the process of the present invention can be used as a tuning process for the trimerization and tetramerization of olefinic monomers. By the term "tuning" as used herein, it is understood that by varying the reaction conditions of the process of the present invention, the amount of trimers and tetramers in the composition of the product produced by the process of the present invention may vary. . This may be useful for a continuous or semi-continuous tuning process for the trimerization and tetramerization of olefinic monomers, wherein the composition of the product may be changed (e.g., from the production of a higher proportion of trimers to a higher proportion of tetramers, or vice versa), changing reactor conditions without having to interrupt the olefinic monomer feed or the trimerization and tetramerization product flow. In particular, this may be especially useful for a continuous or semi-continuous tuning process, for the trimerization and tetramerization of ethylene, wherein the composition of the product may be changed (e.g., from the production of a greater proportion of 1-hexene to one higher ratio of 1-octene, or vice versa) by changing reactor conditions without having to interrupt the olefinic monomer feed or the trimerization and tetramerization product flow. In one embodiment of the present invention, there is a process for the trimerization and tetramerization of olefinic monomers, wherein the process comprises contacting at least one olefinic monomer under trimerization and tetramerization reaction conditions with a catalyst system of the process of the present invention, wherein the process is a continuous or semi-continuous process and the reaction conditions vary during the process. Variation of reaction conditions can be made to make continuous adjustments to a process to ensure consistent product distribution or can be made to a process to change the distribution of products produced. A preferred version of this embodiment is a process for the trimerization and tetramerization of ethylene, wherein the process comprises contacting ethylene with a catalyst system of the process of the present invention, wherein the process is a continuous or semi-continuous process and the reaction conditions vary during the process. The separation of the products, reagent and catalyst can be done by any technique known to someone skilled in the art, such as distillation, filtration, centrifugation, liquid / liquid separation, extraction, etc.

Additional details can be found with respect to reactors, solvents, separation techniques, and the like, in WO 02/04119. The use of the process of the present invention for the trimerization and catalytic tetramerization of olefinic monomers provides a simplified method of producing trimers and tetramers of olefinic monomer with reduced formation of by-products compared to equivalent trimerization and tetramerization processes. In particular, the use of the process of the present invention for the trimerization and catalytic tetramerization of ethylene to 1-hexene and 1-octene provides a process with very high selectivity for 1-hexene and 1-octene over all other products formed in the Ce and C8 fractions respectively and with reduced formation of by-products compared to equivalent trimerization and tetramerization processes. The overall yield of 1-hexene and 1-octene in the process for the trimerization and tetramerization of ethylene of the present invention depends on the reaction conditions employed. Typically, the selectivity of the trimerization and tetramerization (ie, the amount of trimers and tetramers of the olefinic monomers in the overall product composition) of the process of the present invention is at least 65% by weight, preferably at least of 70% by weight, more preferably at least 75% by weight of the composition of the overall product. The selectivity of the trimerization and tetramerization for the trimerization and tetramerization of ethylene (ie, the amount of the C6 and C8 fraction in the overall product composition) using the process of the present invention is at least 65% by weight, preferably at least 70% by weight, more preferably at least 75% by weight, of the overall product composition. The amount of 1-hexene produced by the trimerization and tetramerization of ethylene using the process of the present invention is typically in the range of 10% by weight to 90% by weight, preferably 11% by weight to 85% by weight, more preferably from 12% by weight to 80% by weight, of the overall product composition. The amount of 1-octene produced by the trimerization and tetramerization of ethylene using the process of the present invention is typically in the range of 10% by weight to 90% by weight, preferably 11% by weight to 85% by weight, more preferably from 12% by weight to 80% by weight, of the overall product composition. The selectivity of 1-hexene (ie, the amount of 1-hexene present in the C fraction of the product composition) in the trimerization and tetramerization of ethylene using the process of the present invention is preferably at least 85% by weight, more preferably at least 90% by weight, more preferably at least 92% by weight of the C6 fraction of the composition of the product.

The 1-octene selectivity (ie, the amount of 1-octene present in the C8 fraction of the product composition) in the trimerization and tetramerization of ethylene using the process of the present invention is preferably at least 85% by weight, more preferably at least 90% by weight, more preferably at least 92% by weight of the C8 fraction of the composition of the product. The amount of solids produced in the trimerization and tetramerization of ethylene using the process of the present invention is typically at most about 5% by weight. Lower levels of solid olefinic and polyethylene waxes produced in the trimerization and tetramerization of ethylene are desirable in commercial operations because this can reduce the amount of fouling of the reactor equipment, reduce the amount of waste by-products and reduce the amount of "stoppages" operational due to maintenance and cleaning of the reactor equipment. The amount of Cι produced in the trimerization and tetramerization of ethylene using the process of the present invention is typically at most about 10% by weight. In an embodiment of the present invention, the olefin product composition of ethylene trimerization and tetramerization using the process of the present invention typically comprises a combined total content of 1-hexene and 1-octene of at least 70% by weight of the overall product composition, where the content of 1-hexene is at least 10% by weight of the overall product composition, the selectivity to 1-hexene is at least 90% by weight of the C6 fraction of the composition of the product, 1-octene content is at least 10% by weight of the overall product composition, the selectivity to 1-octene is at least 90% by weight of the C8 fraction of the product composition, and the amount of solids produced at a time of much 5% by weight of the total product composition. In another embodiment of the present invention, the composition of the olefinic product of the trimerization and tetramerization of ethylene using the process of the present invention comprises a total content of compounds other than 1-hexene and 1-octene of at most 35% by weight of the overall product composition, preferably at most 30% by weight and more preferably at most 27% by weight, wherein the content of 1-hexene is at least 10% by weight of the overall product composition, selectivity to 1-hexene is at least 90% by weight of the fraction of the product composition, the content of 1-octene is at least 10% by weight of the overall product composition, the selectivity to 1- Octene is at least 90% by weight of the C8 fraction of the product composition, and the amount of solids produced is at most 5% by weight of the overall product composition. The process of the present invention is illustrated by means of the following non-limiting examples. EXAMPLES General Procedures and Characterization All chemical substances in the preparations were purchased from Aldrich and used without further purification unless otherwise stated. All operations with the catalyst systems were carried out under a nitrogen atmosphere. All solvents used were dried using standard procedures. Anhydrous toluene (99.8% purity) was dried over 4A molecular sieves (final water content of about 3 ppm). Anhydrous heptane (99.8% purity) was dried by passing over 4A molecular sieves (final water content of about 1 ppm). Ethylene (99.5% purity) was purified on a column containing 4Á molecular sieves and BTS catalyst (BASF) in order to reduce the water and oxygen content to < 1 ppm. The oligomers obtained were characterized by Gas Chromatography (GC), in order to evaluate the distribution of oligomers using an HP 5890 series II device and the following chromatographic conditions: Column: HP-1 (cross-linked methylsiloxane) , film thickness = 0.25 μm, internal diameter = 0.25 mm, length 60 m (by Hewlett Packard); injection temperature: 325 ° C; Detection temperature: 325 ° C; Initial temperature: 40 ° C for 10 minutes; temperature program speed 10.0 ° C / minute; final temperature: 325 ° C for 41.5 minutes; Internal standard: n-hexylbenzene. The yields of C4-C30 olefins were obtained from the GC analyzes. The term "trimerization selectivity" when used in connection with the trimerization of ethylene means the amount of C6 fraction formed in the composition of the product, determined by GC. The term "tetramerization selectivity" when employed in connection with the tetramerization of ethylene means the amount of C8 fraction formed in the composition of the product, determined by GC. The term "1-hexene selectivity" when employed in connection with the trimerization of ethylene means the amount of 1-hexene formed in the C fraction of the composition of the product, determined by GC. The overall yield of 1-hexene in the trimerization of ethylene is the product of the "trimerization selectivity" multiplied by the "selectivity to 1-hexene". The term "1-octene selectivity" when employed in connection with the tetramerization of ethylene means the amount of 1-octene formed in the C8 fraction of the composition of the product, determined by GC. The overall yield of 1-octene in the trimerization of ethylene is the product of the "trimerization selectivity" multiplied by the "1-octene selectivity". The amount of "solids", consisting mainly of heavy waxes and polyethylene, has been determined by weighing, after separation from the reactor wall and its appendages, followed by washing with toluene on a glass fiber filter (P3) and vacuum drying. The total amount of "total product" is the sum of the quantity of mainly olefinic product derived from GC analysis and the amount of solids. The NMR data were obtained at room temperature with a Varian 300 MHz or 400 Mhz apparatus. Catalyst Systems The catalyst compositions of the present invention were prepared from catalyst precursor compositions containing ligands A, B, C and D and a source of chromium, these components are described below.

Source of chromium The complex of chromium trichloride tris (tetrahydrofuran), ie CrCl3 (THF) 3, and tris (2,4-pentanedionate), also known as tris (acetylacetonate), ie Cr (acac) 3, is They have used as the sources of chromium in simultaneous reactions of tri and tetramerization of ethylene. Component Ligand A (comparative) The ligand (2-methoxyphenyl) (phenyl) PN (CH 3) P (2-methoxyphenyl) (phenyl) was prepared by first forming a suspension of 0.42 g of lithium (60 mmol) in 80 ml of THF, to which 9.66 g of (2-methoxyphenyl) 2P (phenyl) (30 mmol) were added at 0 ° C under an argon atmosphere. The mixture was stirred for 4 hours, after which time an aliquot of 5 ml of methanol was added. 60 ml of toluene were added to the mixture, after which the solution was extracted with two 40 ml portions of water. The extracted toluene solution was then concentrated to a volume of approximately 20 ml, which resulted in the formation of a suspension. The concentrated toluene solution was filtered, and 4.6 g of C2C16 was added to the toluene filtrate, which was then stirred for 2 hours at 90 ° C. The HCl gas that came off the reaction was "trapped" in an alkali bath. The mixture was then cooled to room temperature and purged with nitrogen until all the remaining HCl present in the solution was removed.

At room temperature, a 5 ml aliquot of triethylamine was added to the concentrated toluene solution and left for a few minutes, after which 6 ml of 2 M H2NMe (12 mmol) were added a few drops at a time. The suspension was filtered and washed with 20 ml of toluene. The toluene filtrate and the toluene wash fraction were combined. The combined toluene fractions were evaporated to dryness and 30 ml of methanol were added. The methanol solution was left overnight at -35 ° C where a white precipitate of (2-methoxyphenyl) (phenyl) PN (CH3) P (2-methoxyphenyl) (phenyl) was formed in the solution. The precipitated ligand was separated. The precipitated ligand consisted of two isomers, a racemic isomer (the RR and / or SS enantiomers of the ligand) and a mesoisomer (the RS enantiomer of the ligand); the proportions of these two isomers were determined by 31P NMR with peaks at 63.18 and 64.8 ppm corresponding to the two different isomers, respectively. The sample consisted of a mixture of both racemic isomers and mesoisomers with weight ratios of 92/8. Composition A 'was prepared (2-methoxyphenyl) (phenyl) P (CH 3) P (2-methoxyphenyl) (phenyl) in a molar ratio of 1: 1 with CrCl 3 (THF) 3 by stirring an equimolar mixture of CrCl 3 (THF) ) 3 and the ligand A component in toluene for 1 hour at 50 ° C, followed by evaporation of the solvent in vacuo and washing the residue with pentane. Component Ligand B (Comparative) The ligand (2-methoxyphenyl) (phenyl) PN (CH 3) P (2-methoxyphenyl) 2 was prepared by first forming a solution of 1.59 g (5 mmol) of (2-methoxyphenyl) 2 PNET 2 in 20 ml. of diethyl ether. To this solution was added 10 ml of a solution of 1 M HCl in diethyl ether (10 mmol of HCl) under an inert atmosphere at room temperature. The suspension thus formed was stirred overnight. The diethyl ether was removed from the product under vacuum and 20 ml of dry toluene were added. The resulting solution was filtered and the toluene was removed from the filtrate under vacuum to give a white solid product (2-methoxyphenyl) 2PC1. A solution of 0.51 g (5 mmol) of triethylamine in 20 ml of dry dichloromethane was added to the product (2-methoxyphenyl) 2PC1. To the resulting mixture, 1.25 ml of a solution of 2 M HNMe in THF (2.5 mmol) was added and the mixture was left stirring overnight. The solvents were removed from the resulting solution in vacuo and 20 ml of dry toluene were added. The mixture is then filtered. The toluene was removed from the filtrate under vacuum, and 10 ml of methanol was added to the residue to yield a suspension, which was filtered once more, to leave the white solid product (2-methoxyphenyl) (phenyl) PN (CH 3) P (2-methoxyphenyl) 2.

Composition B '(2-Methoxyphenyl) (phenyl) PN (CH 3) P (2-methoxyphenyl) 2 was prepared in a 1: 1 molar ratio with CrCl 3 (THF) 3 in a manner similar to Composition A'. Component Ligand C (Comparative) Ligand (phenyl) 2 PN (isopropyl) P (phenyl) 2 was prepared by the following method. At 0 ° C, under a nitrogen atmosphere, 15 ml of triethylamine was added to 6.3 g (phenyl) 2 PCl in 80 ml of dry dichloromethane. To the resulting mixture, 0.844 g of isopropylamine was added and allowed to stir overnight at room temperature. The solvents were removed from the resulting solution in vacuo and 50 ml of dry toluene was added. The mixture was then filtered over a small layer of silica. The toluene was removed from the filtrate in vacuo. The product (phenyl) 2 PN (isopropyl) P (phenyl) 2 was separated as a white solid. The crystallization of ethanol produced (phenyl) 2 PN (isopropyl) P (phenyl) 2 as white crystals. Component Ligand D The ligand (phenyl) 2 PN (isopropyl) P (2-methoxyphenyl) 2 was prepared by the following method. Under a nitrogen atmosphere, 12 ml of triethylamine was added to 3.39 g of isopropylamine in 10 ml of dry toluene. To the resulting mixture, 5.15 ml (phenyl) 2PC1 was slowly added and allowed to stir overnight at room temperature. The precipitate was removed by filtration. The solvents were removed from the resulting solution in vacuo. Pentane was added to the evaporation residue and then the solvent was removed in vacuo from the pentane solution, obtaining (phenyl) 2PNH (isopropyl) as a colorless oil, which crystallized when left at room temperature. Under a nitrogen atmosphere, 3 ml of triethyl amine was added to 0.9 g of (phenyl) 2 PNH (isopropyl) in 5 ml of dry dichloromethane. To the resulting mixture, 1.1 g of (2-methoxyphenyl) 2PC1 was added and left stirring for one week at room temperature. 5-10 ml of dry toluene were added to the resulting reaction mixture. The precipitate was removed by centrifugation. The solvents were removed from the resulting solution in vacuo. The resulting mixture was washed first with pentane and then with methanol yielding a white solid. The white solid was washed with pentane and dried in vacuo. Performance of 0.7 g of (phenyl) 2PN (isopropyl) P (2-methoxyphenyl) 2. Cocatalyst The cocatalyst used in the following experiments was selected from: methyl aluminoxane (MAO) in toluene, [Al] = 5.20% by weight, supplied by Crompton GmbH, Bergkamen , Germany; tetraisobutyl dialuminoxane (TIBAO) 30% by weight in cyclohexane, [Al] = 5.44% by weight, supplied by Witco Polimer Chemicals, Witco GmbH, Bergkamen, Germany. EXAMPLES 1-11 Preparation of the catalyst system for simultaneous trimerization and tetramerization in a batch autoclave In a Braun MB 200-G drying box, the CrCl 3 1: 1 complexes of ligands A or B (ie compositions A ' or B ', indicated in Table 1) were placed in a glass bottle. The catalyst precursor composition was converted to the catalyst solution by adding 3 or 1.5 mmol of MAO solution in toluene (approximately 1.6 g or 0.8 g of MAO solution), followed by typically 4 g of dry toluene. Finally the bottle was sealed by means of a diaphragm cap. These catalyst solutions, or part of these solutions, were used in the simultaneous reaction of tri- and tetramerization of ethylene. Alternatively, chromium tris (acetylacetonate) (typically 30 μmol) and the amount of the ligand component C or D, as indicated in Table 1, were placed in a glass bottle, to which was added dry toluene (typically 4 g. ) to obtain the catalyst precursor solution. Finally the bottle was sealed with a diaphragm cap.

These catalyst precursor solutions, or part of these solutions, were autoclaved as catalyst precursor solutions and activated by pre-dosed MAO or TIBAO in situ and subsequently used in the simultaneous tri- and tetramerization of ethylene reaction. . Trimerization and simultaneous tetramerization reactions of ethylene in a 1.0 liter batch autoclave Simultaneous tri- and tetramerization experiments were carried out in a 1.0 liter steel autoclave equipped with a cooling jacket with a heating / cooling bath (for example, Julabo , model ATS- 2) and a turbine / gas agitator and deviators. The reactor was cleaned by introducing 250 ml of toluene, MAO (0.6 g of solution) or a similar amount of a TIBAO solution, and subsequently stirred at 70 ° C under nitrogen pressure of 0.4-0.5 MPa for 30 min. The content of the reactor was discharged via a tap at the base of the autoclave. The reactor was evacuated to approximately 0.4 kPa and charged with approximately 250 ml of toluene, heated to 40 ° C and pressurized with ethylene at 15 bar gauge or as indicated in Table 1. While stirring, it was added to the reactor. a solution of MAO (typically an admission of 3.12 g, 6 mmol of Al) or a solution of TIBAO as indicated in Table 1, with the help of toluene to achieve an atomic ratio of Al / Cr of 200 (typically, the total volume injected was approximately 25 ml: the MAO solution diluted with toluene to 8 ml was injected and the injector system was rinsed twice with approximately 8 ml of toluene) and stirring at 800 rpm continued for 30 minutes. The Cr catalyst precursor system (typically 30 μmol at the Cr inlet), prepared as described above, was introduced into the stirred reactor using an injection system with the aid of toluene (the total volume injected was approximately 25 ml. : the catalyst solution diluted with toluene to 8 ml was injected and the injector system was rinsed twice with approximately 8 ml of toluene). The initial charge of the reactor was approximately 300 ml, mainly of toluene. The addition of the catalyst system resulted, after an induction period of about 5 minutes, in an exotherm (generally about 5-10 ° C), which generally reached a maximum in 1 minute and then set the temperature at 40 ° C and the pressure at 15 bar gauge, unless otherwise indicated in Table 1 After consuming the desired volume of ethylene, simultaneous tri- and tetramerization was stopped by rapid cooling to room temperature (in about 5 minutes), followed by ethylene vent, decanting the product mixture into a collection bottle using a tap at the base of the autoclave. Exposure of the mixture to the air resulted in a rapid deactivation of the catalyst.

After the addition of n-hexylbenzene (0.5-3.5 g) as an internal standard to the crude product, the amount of C-C30 olefins and the purity of C6, C8 and C6 olefins was determined by gas chromatography. The experimental data is reported in Table 1. In the case of experiments at 30 bar gauge ethylene pressure, a similarly equipped, charged 0.5 liter steel autoclave was used (similar to the procedure described above for the liter autoclave) with 150 ml of toluene, a solution of MAO or a solution of TIBAO and a catalyst system of Cr. The amounts of the catalyst system of Cr, MAO solution, TIBAO, solvent and ethylene consumption were typically half of those used in the corresponding 1.0 experiments to maintain the same atomic ratio of Al / Cr (of about 200) and final alpha olefin concentration as much as practical. The experimental data are provided in Table 1 below. t Q rrj I l # Comparative example f Cycle frequency (TOF) in ethylene converted kmol per hour / mol of catalyst (kmol / mol * h); Number of cycles (TON) in ethylene converted kmol / mol catalyst (kmol / mol). * 1-hexene% by weight of the C portion of the product composition. **% 1-octene by weight of the C8 portion of the composition of the product. t Olefin predominantly branched and / or internal, unless otherwise indicated. tt Approximately 50% by weight of 1-decene of the Cio portion of the product composition. C6 Hydrocarbons containing 6 carbon atoms. l-Cβ 1-hexene. C8 Hydrocarbons containing 10 carbon atoms. 1-C8 1-octene. Cío Hydrocarbons that contain 10 carbon atoms. C? 2-C24 Hydrocarbons containing 12 and / or 14 carbon atoms.

Solids The amount of wax and polyethylene separated by filtration. Total Product The amount of C4-100 olefins, derived from the GC analysis, including the amount of solids.

It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Claims (9)

1. CLAIMS Having described the invention as above, the content of the following claims is claimed as property: 1. A process for the simultaneous trimerization and tetramerization of olefinic monomers, characterized in that it comprises contacting at least one olefinic monomer with a catalyst system. comprising: a) a source of chromium; b) a ligand having the general formula (I); (R1) 2P-XP (R1) m (R2) n (I) wherein: X is a bridging group of the formula -N (R3) -, wherein R3 is selected from hydrogen, a hydrocarbyl group, a group substituted hydrocarbyl, a silyl group or derivative thereof; the R1 groups are independently selected from an optionally substituted aromatic group bearing a polar substituent in at least one of the ortho positions; and the R2 groups are independently selected from substituted or unsubstituted aromatic groups, including heteroaromatic groups, which do not contain a polar substituent at any of the ortho positions; with the proviso that m is 0 or 1, n is 1 or 2 and the total of m + n is 2; optionally, any of the groups R1 and R2 may be independently linked to one or more of each other or to the bridging group X to form a cyclic structure; and c) a cocatalyst, at a pressure in the range of below atmospheric to about 40 bars gauge and a temperature in the range of about 0 ° C to about 120 ° C.
2. 2. A process according to claim 1, characterized in that R3 is selected from C?-C15 alkyl groups, substituted C1-C15 alkyl groups, C2-C? Alkenyl groups, substituted C2-C alkenyl groups, cycloalkyl groups C3-C15, substituted C3-C5 cycloalkyl groups, C5-C15 aromatic groups and substituted C5-C15 aromatic groups, preferably C1-C15 alkyl groups.
3. 3. A process according to any of claims 1 and 2, characterized in that m is 0 and n is 2.
4. 4. A process according to any of claims 1 to 3, characterized in that the R2 groups are independently selected from optionally substituted phenyl groups which do not contain a polar substituent in any of the ortho positions.
5. 5. A process according to any of claims 1 to 4, characterized in that the group R1 is independently selected from substituted or unsubstituted aromatic groups bearing an optionally branched C? -C2o alkoxy group in at least one of the ortho positions , preferably an o-anisyl group.
6. 6. A process according to any of claims 1 to 5, characterized in that the temperature is in the range of 40 ° C to 100 ° C.
7. 7. A process according to any of claims 1 to 6, characterized in that the amount of chromium, a), and the amount of ligand b), are present in a molar ratio in the range of 1: 9 to 1: 1.1. .
8. 8. A process according to any of claims 1 to 7, characterized in that the olefinic monomer is selected from ethylene, propylene, optionally branched C4-C2 alpha-olefins, optionally branched C-C2 internal olefins, C-C24 vinylidene olefins. optionally branched, optionally branched C4-C24 cyclic olefins, optionally branched C4-C2 dienes, and optionally branched C4-C24 functionalized olefins.
9. 9. A process according to claim 8, characterized in that the olefinic monomer is ethylene.