Dimerisierungsverfahren

1,143,539. Dimerization of unsaturated nitriles. NATIONAL DISTILLERS & CHEMICAL CORP. 25 Feb., 1966 [2 March, 1965], No. 8501/66. Heading C2C. Unsaturated α,α-dinitriles are prepared by dimerizing an acrylonitrile compound of the formula R 1 R 2 C = CHCN where R 1 and R 2 are hydrogen or C 1-10 organic radicals, under an inert atmosphere and in the presence of an inert solvent and a tricycloalkyl-phosphine catalyst, other than tricyclopentyl or tricyclohexyl phosphine. It is preferred to effect the reaction at 0‹-150‹ C. in the presence of a solvent which is a C 6-10 aromatic hydrocarbon optionally in admixture with a C 2-12 alkanol. Examples relate to the preparation of 2- methylene glutaronitrile from acrylonitrile in the presence of tricycloheptyl or tricyclohexyl phosphine.