Diesters of (E)-2-alkylidenesuccinic acids obtained by conjugate addition of nitroalkanes to dimethylmaleate can be selectively monohydrolyzed at the more reactive carboxyl group to the corresponding half-ester. Alternatively, total hydrolysis to the diacid allows a subsequent selective methyl esterification of the alkanoic carboxyl group to give the other regioisomeric half-ester. 2-Alkylsuccinic
Nitroalkanes react with dimethyl maleate giving a tandem Michaeladdition/elimination of nitrous acid. The obtained (E)-2-alkylidene dimethyl succinates are: (i) reduced to the corresponding 2-alkyl dimethyl succinates which after hydrolysis produce 1,4-dicarboxylic acids that are prone to convert into the corresponding 3-alkyl succinic anhydrides or (ii) hydrolysed to (E)-2-alkylidene-succinic acids that