Investigations for synthesizing chlorothricolide

Functionally substituted acrylates 8a,b obtained by direct lithiation of the corresponding acids, and cyclohexanone derivative 6 accessible in a five step sequence afforded spirotetronates 9a,b containing the carbon skeleton and the stereochemistry of the top half of chlorothricolide 1 (R = H). Subsequent direct lithiation of the tetronate moiety in a-position enabled the introduction of the required a-hydroxy group.