process for isomerisation of 1.4.diclorobutene.2 to 3.4.diclorobutene.i and 3.4.diclo robutene. the diclorobutene to 1.4. 2.

摘要

1332213 Isomerization of dichlorobutenes BP CHEMICALS INTERNATIONAL Ltd 29 Feb 1972 [16 March 1971] 6973/71 Heading C2C Each of 1,4-dichlorobutene-2 and 3,4-dichlorobutene-1 is isomerized to the other by contacting (e.g. at 80-160‹ C.) with a catalyst composition comprising one or more Cu compounds (e.g. organic or inorganic salts) and an alkyl, cyoloalkyl, aryl or aralkyl substituted urea wherein the hydrocarbon substituent may be further substituted. The substituted urea may be present in an amount of between 0À5 and 10% by weight based on the total weight of catalyst and dichlorobutenes. The process is preferably carried out continuously and a mixture of the two isomers, obtained by the direct chlorination of butadiene, may be used as starting material. In the examples, the catalyst compositions used comprise one of cuprous chloride, cupric naphthenate, cupric oleate and cupric stearate together with one of various substituted ureas: methyl urea, ethyl urea, isopropyl urea, phenyl urea, tetramethyl urea, p-phenetyl urea, mtolyl urea, 1,3-dibenzyl urea and 1,3-dicyclohexyl urea.