A Concise and Versatile Total Synthesis of All Stereoisomers of Tarchonanthuslactone

We describe the versatile and concise total synthesis of all stereoisomers of tarchonanthuslactone from ( R )- or ( S )-3-hydroxybutyrate via eight steps. The key steps of the synthesis include a highly diastereoselective chelation-controlled Mukaiyama aldol reaction of a p -methoxybenzyl-protected aldehyde and a Yamaguchi lactonization of a δ-hydroxy- trans -α,β-unsaturated carboxylic acid.