A new method for the synthesis of unsymmetric disubstituted isopropylidene malonates has been developed, in which conjugate addition of isopropylidene alkylidenemalonates with Grignard reagents, followed by α-alkylation, regiospecifically introduces two alkyl groups in α and β position of the original isopropylidene alkylidenemalonates. Disubstituted isopropylidene malonates can be further hydrolyzed and decarboxylated to give corresponding carboxylic acids, or subjected to decarboxylative alcoholysis to give esters. This method may also be used efficiently to synthesize carboxylic acids and esters with α and β branched chains.

Key words: CONJUGATION, ALKYLATION, MALONIC ACID P, ADDITION REACTION, ISOPROPYL ESTER, GRIGNARD REAGENT