Enantioselective synthesis of cyclopropyl δ-lactonealdehydes and dodecyl-5-ene-1-yne-3-ol: advanced intermediates of solandelactone A and B

A stereocontrolled synthesis of cyclopropyl δ-lactonealdehydes and dodecyl-5-ene-1-yne-3-ol is accomplished with predictable absolute stereochemistry via organocatalytic and catalytic asymmetric transfer hydrogenation reactions. The salient feature of this protocol is the genesis of chirality through an organocatalytic reaction and utilized for installing a critical bifunctional trans-cyclopropane motif, which is a key segment of every representative member of the oxylipin class of natural products such as solandelactone A and B.