HYDROFORMYLATION PROCESS

摘要

1448090 Oxo synthesis; rhodium-containing organic complexes MONSANTO CO 28 Nov 1973 [29 Nov 1972] 55078/73 Headings C2C C2B C2J and C2P An aldehyde is obtained by hydroformylation of a C 2 to C 30 olefinically unsaturated compound by contacting the unsturated compound, CO and H 2 at 60‹ to 180‹ C. in the presence of a catalyst of a rhodium complex of the formula [Rh(CO) x L y ]+Anwherein is a number from 1 to 5, y is a number from 1 to 4 such that x+y=5, L is a tertiary organophosphorus, tertiary organo-arsenic, -antimony, or -nitrogen compound having from 3 to 90 carbon atoms, or a binary organosulphur compound having 2 to 60 carbon atoms, and Anis a non-co-ordinating anionic moiety, e.g. BPh 4 - (where Ph is phenyl), BF 4 -, ClO 4 -, PF 6 -, NO 3 - or SiF 6 -. Specified ligands L are P(C 6 H 5 ) 3 , P(C 6 H 5 O) 3 , As(C 6 H 5 ) 3 , Sb(C 6 H 5 ) 3 , N(C 6 H 5 ) 3 and S(C 2 H 5 ) 2 and specified complexes are An excess of the ligand L may be used as liquid reaction medium and this ligand may be the same as or different from that present in the complex. Various other liquids may also be used as reaction medium, and several such liquids are specified. The catalyst may be used in the liquid phase or dispersed on a porous solid support such as silica, carbon or alumina. Several olefinic compounds suitable for use as feedstock are specified and examples are given for the hydroformylation of 1-hexene, 1-octene, isomerized octene, isomerized dodecene, 1-dodecene, styrene,α-methylstyrene, ethyl vinyl ether, ethylene, propylene, vinyl acetate, isomerized pentenes, ethyl acrylate, iso-butylene and 1,5-hexadiene. The cationic rhodium complexes of the given formula are prepared by adding to a methanol solution of the ligand L, under a nitrogen atmosphere, an appropriate rhodium precursor such as [Rh(COD)Cl] 2 where COD is 1,5-cyclooctadiene, stirring the mixture and after 30 minutes adding a salt of the anion An-, e.g. NaBPh 4 or NaBF 4 , sitrring the suspension for 30 minutes and then recovering the precipitated product which is then washed with ether, dried, and then treated, e.g. in acetone solution, with carbon monoxide. An example is given for the production of Rh(COD)(Ph 3 P) 2 BPH 4 as intermediate and its conversion to by treatment with CO in acetone solution.