Olefin disproportionation catalyst

Claim 1

A catalyst composition consisting essentially of (1) at least one neutral carbene complex having the general formula ##STR26## wherein R is an aryl or substituted aryl radical containing 6 to 30 carbon atoms per radical wherein the substituted aryl radical can have one or more substituents each of which can be the same or different and selected from the group consisting of halides, alkoxides and alkyl radicals containing 1 to 20 carbon atoms per radical; R I is selected from the group consisting of alkyl, cycloalkyl, aryl, substituted aryl, trialkylsilyl, and triarylsilyl radicals containing 1 to 30 carbon atoms per radical with the aryl substituents being the same as for the substituted aryl of R; Y is O, Se, S, N, or P; m is 1 when Y is O, Se, or S and 2 when Y is N or P; M is tungsten or rhenium; each L is individually selected from CO, NO, PF 3 , PCl 3 , or pyridine; L I is cyclopentadienyl; p is 0 or 1; and n is 5 when p is 0 or 2 when p is 1, (2) at least one halogenated promoter selected from the group consisting of fully halogenated methanes and halogenated unsaturated organo compounds having 3 to 30 carbon atoms per molecule, no hydrogens other than those bonded to the ring carbons of an aromatic ring, and a fully halogenated alkyl radical bonded to the carbon of an olefinic carbon-carbon double bond, a ketone carbonyl double bond, or an aromatic carbon-carbon double bond and wherein the halogens of the halogenated promoters are individually selected from chlorine, bromine, and iodine, and (3) at least one tin promoter selected from (a) tetraorganotin compounds having 4 to 40 carbon atoms per molecule and the formula SnR.sup.II.sub.4 wherein each R II contains 1 to 10 carbon atoms per radical and is individually selected from the group consisting of alkyl, cycloalkyl, aryl, and substituted aryl radicals wherein the substituents are individually selected from alkyl or alkyoxy radicals or chloride or bromide, and (b) organotrihalotin compounds having 1 to 10 carbon atoms per molecule and the formula R.sup.II SnX.sub.3 wherein R II is as defined above and wherein each X is individually selected from the group consisting of chloride, bromide, and iodide, wherein said neutral carbene complex of said halogenated promoter, and said tin promoter are present in such amounts as to have a catalytic effect upon the disproportionation of 1-pentene.