SYNTHESIS OF MONOESTER OR DIESTER OF 9, 10-ENDOETHANO-9, 10-DIHYDROANTHRATHENE-11, 11-DICARBOXYLIC ACID, OBTAINED NOVEL MONOESTER OR DIESTER AND APPLICATION THEREOF TO SYNTHESIS OF SYMMETRIC OR ASYMMETRIC METHYLIDENE MALONATE

摘要

These new mono- and diesters correspond to the following chemical structural formula (II): …IMAGE… in which R1 and R2 are identical or different and may denote H or an alkali or alkaline-earth metal atom, a linear or branched alkyl group containing from 1 to 6 carbon atoms, alicyclics containing from 3 to 6 carbon atoms, alkenyls containing from 2 to 6 carbon atoms, defined in their cis or trans form, or else alkynyls containing from 2 to 6 carbon atoms, optionally functionalised by one or more groups such as ether, epoxide, halo, cyano, ester, aldehyde, ketone, aryl etc., where R1 and R2 cannot simultaneously be H or ethyl. These addition products constitute valuable intermediates for the preparation of methylidenemalonates in high yields, in a high purity.