Catalytic isomerization of 2 - methyl - 3 - butene - nitrile to linear pentene nitriles in the presence of certain metal salt - and / or tri - (hydrocarbyl radical) - boron - promoters

摘要

1,210,969. Isomerization of 2-methyl-3- butene nitrile to linear pentenenitriles. E.I. DU PONT DE NEMOURS & CO. 11 Nov., 1968 [26 Oct., 1967], No. 48417/68. Heading C2C. 2 - Methyl - 3 - butenenitrile is isomerized to linear pentenenitriles by contacting it with a catalyst comprising (a) a zero-valent nickel complex which is a nickel compound of the formula Ni(PXYZ) 4 where X is OR and Y and Z are OR or R, wherein R is an alkyl or aryl group having up to 18 carbon atoms and wherein any of X, Y and Z may be cojoined, and (b) an organoboron compound of the Formula B(R) 3 , wherein R is an alkyl or aryl group containing up to 18 carbon atoms, or a salt of a metal of atomic number 13, 21-32, 39-50 or 57-82, the molar ratio of (b) to (a) being from 1 : 20 to 50 : 1. The reaction may be effected batchwise or continuously at a temperature of 10-200‹ C., preferably under an inert, atmosphere, and an inert solvent may be present. Preferred catalysts are those wherein the nickel complex is (1) a preformed complex of the formula Ni(PXYZ) 4 where any two of X, Y and Z are alkylene or alkoxylene of up to 6 carbons, the third of X, Y and Z being as defined above; or (2) the product of reaction between an alkyl or aryl phosphite with an intermediate nickel compound of the formula Ni(ASP1/SP)(ASP2/SP)(ASP3/SP)(ASP4/SP), where ASP1/SP-ASP4/SP are the same or different neutral ligands and are each (a) carbon monoxide or (b) M(XSP1/SPYSP1/SPZSP1/SP) wherein M is P, As or Sb n and XSP1/SP, YSP1/SP and ZSP1/SP are the same or different and are R 1 , NR 2 , Cl or F, R being alkyl or aryl of up to 18 carbon atoms, or ASP1/SP and ASP2/SP are, together, a single acrylonitrile molecule and ASP3/SP and ASP4/SP are together a single acrylonitrile molecule or each a group M(XSP1/SPYSP1/SPZSP1/SP) as defined above; both the final zero-valent nickel complex and the intermediate nickel compound may be pre-formed or formed in situ. The anions in the metal salts employed as promotors may be, for example, halides, sulphates, phosphates and aliphatic carboxylates.