Methyl 4-oxothiolane-3-carboxylate and methyl 2-methyl-4-oxothiolane-3-carboxylate anions as synthetic equivalents of α-acrylate and α-crotonate anions. Formal synthesis of integerrinecic acid

Abstract

The base-promoted fragmentation of the C-alkylation products (6a–h) and (8a–e) of methyl 4-oxothiolane-3-carboxylate (4) and methyl 2-methyl-4-oxothiolane-3-carboxylate (5) gave good yields of the α-substituted acrylates (7a–h) and α-substituted crotonates (9a–e); thus the corresponding heterocyclic anions (1a) and (1b) could be considered to be synthetic equivalents of α-acrylate and α-crotonate anions respectively. A formal synthesis of integerrinecic acid (10) is reported, demonstrating the usefulness of this strategy in natural product chemistry.