GB946062A - Metal complexes between transition metals and trivalent phosphorus compounds - Google Patents

Abstract

The invention comprises a complex of a transition metal in a valence state of less than +1 selected from Group V, VI, VII or VIII of the Periodic Table and a trivalent phosphorus compound having at least one RwZ-group bonded to the phosphorus atom, wherein R is an unsubstituted or halogen-substituted alkyl, aryl, alkaryl or aralkyl group, Z is oxygen, sulphur or nitrogen and w is 1 when Z is oxygen or sulphur, or 2 when Z is nitrogen. The trivalent phosphorus compound may contain one, two or three RwZ-groups and may suitably be a phosphinite, a phosphonite or a phosphite of an aliphatic or aromatic monohydric hydroxy compound or an amidophosphinite, an amidophosphonite or amidophosphite of an aliphatic or aromatic amine. The trivalent phosphorus compound is preferably a compound of the formula (RwZ)x-P-Ry1 wherein R, Z and w are as defined above and R1 is an unsubstituted or halogen-substituted alkyl, aryl, alkary or aralkyl group, x is 1, 2 or 3 and x+y=3. Preferably x is 3 and R and R1 are alkyl groups having not more than 20 carbon atoms. The complexes may be prepared by dissolving a salt of the transition metal in the trivalent phosphorus compound and hydrogenating the solution. The hydrogenation may be carried out at from 50 DEG to 200 DEG C. under a hydrogen pressure of from less than 1 atmosphere to 100 atmospheres. Preferably the hydrogenation is effected at about 100 DEG C. under a hydrogen pressure of 1 to 10 atmospheres. The transition metal salt may be a salt of an inorganic or organic acid, e.g. a non-oxidising inorganic acid or a carboxylic acid. Preferred salts are chlorides, bromides, cyanides, acetates, propionates and butyrates, but salts of polybasic acids such as sulphuric acid or phosphoric acid and of sulphonic and phosphonic acids may also be used. The mole ratio of the phosphorus compound to the metal may suitably be from 10:1 to 50:1 and the hydrogenation may be carried out in the presence of a nitrobenzene. The transition metal in the complex may be present in any desired positive low valency state of less than +1 or negative valency state depending on the extent of the hydrogenation and the complex generally comprises one metal atom and a plurality of phosphorus compound molecules. Preferred transition metals are Group VIII metals, e.g. Fe, Co, Ni, Rh and Pt. Examples are given for the production of COCl2 complexes with various phosphite triesters, of cobalt acetate with triethyl phosphite, of NiCl2 6H2O, RLCl3. 3H2O and Fe2(SO4)3 and H2PtCl6 both containing water of crystallisation with triethyl phosphite. Other complexes are specified in which the transition metal is vanadium, antimony, bismuth, chromium, molybdenum, tungsten, manganese, rhenium, ruthenium, palladium, rhodium, osmium and iridium. The complexes are useful as gasoline additives (see Division C5) and as hydrogenation catalysts and the invention also includes a process for the hydrogenation of a hydrogenatable organic compound by contacting the latter with hydrogen in the liquid phase and in the presence of one or more of the metal-containing complexes. A biphyllic ligand may be added to the complex before use as hydrogenation catalyst. Suitable biphyllic ligands are the trivalent phosphorus compounds used to form the complexes, diethyl thio-urea, triphenyl arsine, triphenyl stibine and phenanthroline. Hydrogenatable organic compounds which may be used include unsaturated and aromatic hydrocarbons (see Division C5), macromolecular hydrocarbon materials (see Division C3), unsaturated alcohols, aldehydes and acids, e.g. acrolein may be hydrogenated to form propionaldehyde, allyl alcohol to form n-propyl alcohol, acrylic acid to form propionic acid, propargyl alcohol to form allyl alcohol and/or n-propyl alcohol, 1-hydroxy-2,4-pentadiene to form 1-hydroxy-2-pentene and/or 1-pentanol, and unsaturated amines or esters, e.g. allyl acrylate and allyl amine to form propyl acrylate and propylamine respectively. Other reduction processes mentioned are the reduction of aldehydes and ketones to alcohols, of acids to aldehydes and ketones, of nitriles to amines, of nitro groups to amino groups and of epoxides to alcohols and/or hydrocarbons and the reduction of phenol, aniline benzene sulphonic acid and heterocyclic compounds such as pyridine, furans, pyrans and acrolein dimer. The reductive cleavage of CH3CH2CH2CH2COOC2H5\t to form CH3(CH2)3CH2OH and C2H5OH is also mentioned. The reduction process may be carried out at from 0.35 atmosphere to 70 atmospheres of hydrogen and suitable temperatures are between 100 and 300 DEG C. A solvent may be present during the hydrogenation. The complex used as catalyst may be prepared separately before use or may be formed in situ by adding the reactants necessary for its preparation to the reactor at the same time as the compound to be hydrogenated and then hydrogenating. Examples are given for the hydrogenation of benzaldehyde to a mixture of benzyl alcohol and toluene.ALSO:Hydrogenatable organic compounds are hydrogenated by contacting them with hydrogen in the liquid phase in the presence of one or more complexes of a transition metal in a valency state of less than +1 selected from Group V, VI, VII or VIII of the Periodic Table and a trivalent phosphorus compound having at least one RwZ group bonded to the phosphorus atom, wherein R is an unsubstituted or halogen-substituted alkyl, aryl, alkaryl or aralkyl group, Z is oxygen, sulphur or nitrogen and w is 1 when Z is oxygen or sulphur or 2 when Z is nitrogen (see Division C2). Specified hydrogenatable organic compounds include macromolecular materials such as polyethylene, polybutadiene, co-polymers of olefins e.g. an ethylenepropylene co-polymer, and polyacroleins. The trivalent phosphorus compound is suitably a phosphite, phosphonite or phosphinite of an aliphatic or aromatic monohydroxy compound or an amidophosphite, amidophosphonite, or amidophosphinite of an aliphatic or aromatic amine. A biphyllic ligand may be added to the complex before use in the hydrogenation process, specified biphyllic ligands being diethylthiourea, triphenyl amine, triphenyl stibine, phenanthroline and a trivalent phosphorus compound of the above type. The hydrogenation may be effected at from 0.35 atmosphere to 70 atmospheres of hydrogen and at between 100 and 300 DEG C. A solvent may also be present. The complex may be prepared separately before use or may be formed in situ by adding the reactants necessary for its preparation to the reactor at the same time as the compound to be hydrogenated and then hydrogenating. The transition metal present in the complex is preferably iron, cobalt, nickel, rhodium or platinum.ALSO:Hydrogenatable organic compounds are hydrogenated by contacting them with hydrogen in the liquid phase and in the presence of one or more complexes of a transition metal in a valency state of less than +1 selected from Group V, VI, VII or VIII of the Periodic Table and a trivalent phosphorus compound having at least one RwZ group bonded to the phosphorus atom, wherein R is an unsubstituted or halogen-substituted alkyl, aryl, alkaryl or alralky group, Z is oxygen, sulphur or nitrogen and w is 1 when Z is oxygen or sulphur or 2 when Z is nitrogen (see Division C2). The trivalent phosphorus compound may be a phosphite, phosphinite, or phosphonite of an aliphatic or aromatic monohydroxy compound or an amidophosphinite, amidophosphonite or amidophosphite of an aliphatic or aromatic amine. A biphyllic ligand may be added to the complex before use in the hydrogenation process, suitable biphyllic ligands being diethylthiourea, triphenyl arsine, triphenyl stibine, phenanthroline, and a trivalent phosphorus compound of the type used to form the complex. The hydrogenation may be carried out at a pressure of from 0.35 atmosphere to 70 atmospheres of hydrogen and suitable temperatures are between 100 DEG and 300 DEG C. A solvent may also be present. The complex may be prepared separately before use or may be formed in situ by adding the reactants necessary for its preparation to the reactor at the same time as the compound to be hydrogenated and then hydrogenating. Hydrogenatable organic compounds include ethylenic, acetylenic, and aromatic hydrocarbons, e.g. ethylene, propylene, butylene, 3-pentyne, 1,3-butadiene, 1,5-hexadiene, 1-pentene, 4-octene, cyclopentene, cyclohexene, cycloheptene, terpenes, fused ring polycyclic olefins, benzene, naphthalene, anthracene and alpha-ethyl naphthalene. The process may also be applied to the reduction of alcohols, epoxides, carbonyl compounds and mercapto compounds (e.g. those present in petroleum) to hydrocarbons. In examples using the above catalysts octene-1 is hydrogenated to n-octane, naphthalene to tetralin and benzaldehyde to toluene. The invention also includes a motor fuel containing a major proportion of hydrocarbons having a boiling point in the gasoline boiling range and a minor proportion of one or more of the above defined complexes. The complexes are stated to serve as antiknock agents.