(-)-METHYL CUCURBATE AND (-)-METHYL JASMONATE BY KINETIC RESOLUTION

The kinetic resolution of a malonate-substituted cyclopentenone gave r ise to the formation of an enantiopure Diels-Alder adduct which was co nverted into methyl dehydrocucurbate 2 of by diastereoselective alkyla tion with (Z)-1-bromo-2-pentene and subsequent borohydride reduction. Selective hydrogenation of 2 with a palladium/calcium carbonate cataly st proved to be a reliable route to (-)-methyl cucurbate (1) the oxida tion of which with pyridinium chlorochromate and subsequent treatment with acid afforded (-)-methyl jasmonate (9).