PROCESS FOR PREPARING ALKYLIDENE SUBSTITUTED SUCCINIC ACID ESTERS

A process for the preparation of alkylidene substituted succinates comprising a step (a) in which is carried out the reaction of a carbonilic compound, a succinic and a base in a reaction medium and a step (b) in which the alkylidene substituted product obtained in (a) is esterified, characterized in that the succinic ester is used in a molar amount substantially equal to, or lower than, the amount of compound carbonilic compound, (ii) the base is used in a molar amount substantially equal to the succinic ester and is selected from metal hydrides and metal and alkoxides, and (iii) the reaction medium comprises an aprotic liquid medium or a protic liquid medium having a Ka, measured in water, lower than that of iPrOH.