GB1398089A - Process for the catalytic dimerisation of acrylonitrile - Google Patents

Abstract

1398089 Dimerisation of acrylonitrile IMPERIAL CHEMICAL INDUSTRIES Ltd 31 Oct 1972 [8 Nov 1971] 51720/71 Heading C2C Acrylonitrile is dimerized to dicyanobutenes, especially 1,4-dicyanobutenes by heating it, in the absence of hydrogen, with a bismuth catalyst. The bismuth catalyst may be elemen. tary bismuth, an inorganic bismuth compound such as a bismuth salt, e.g. BiCl 3 , BiBr 3 , bismuth nitrate or bismuth carbonate, or bismuth oxide or hydroxide; or an organic bismuth compound, e.g. BiR 1 R 2 R 3 where R 1 , R 2 and R 3 are hydrocarbyl radicals, e.g. alkyl, cycloalkyl, aralkyl or aryl and in particular bismeth triphenyl, bismuth triethyl and bismuth tricyclohexyl The bismuth hydrocarbyl catalyst may be pre-activated by heating in a stream of hydrogen. The bismuth catalyst may also be used in admixture with transition metal catalysts by mixing the bismuth compound and the transition metal compound, e.g. molybdenum carbonyl, palladium acetate, ruthenium acetylacetonate, cobalt acetate or cuprous chloride and pre-reducing in a stream of hydrogen. The 1,4-dicyanobutenes may be hydrogenated to adiponitrile and either directly, or in two stages via adiponitrile to hexamethylenediamine.