Preparation of alkyl (un)substituted cyclohexane dicarboxylic acids, useful as polymer plasticizers, comprises reaction of a diene-maleic acid anhydride mixture, esterification and hydrogenation.

摘要

Preparation of alkyl (un)substituted cyclohexane dicarboxylic acids or corresponding derivatives comprises: (A) reaction of a diene-maleic acid anhydride mixture to form an alkyl (un)substituted cyclohexene dicarboxylic acid anhydride in the condensed phase; (B) formation of the esters; and (C) hydrogenation to the corresponding cyclohexane derivative in either order. Preparation of alkyl (un)substituted cyclohexane dicarboxylic acids or corresponding derivatives (I) comprises: (A) reaction of a diene-maleic acid anhydride mixture to form an alkyl (un)substituted cyclohexene dicarboxylic acid anhydride in the condensed phase; (B) formation of an ester of an alkyl substituted or unsubstituted cyclohexene dicarboxylic acid anhydride; and (C) hydrogenation of the ester from step (B) to the corresponding cyclohexane derivative or (B') hydrogenation of the alkyl (un)substituted cyclohexene dicarboxylic acid anhydride from step (A), followed by (C') formation of an ester from the cyclohexane dicarboxylic acid anhydride from step (B'). Independent claims are also included for the following: (1) a mixture (II) of alkyl (un)substituted cyclohexane dicarboxylic acids or derivatives (I); and (2) a process for the separation of butadiene from butadiene containing hydrocarbon streams comprises: (i) reaction of the hydrocarbon stream with maleic acid anhydride; and (ii) separation of the resulting cyclohexene dicarboxylic acid anhydride from the remaining hydrocarbons.