Asymmetric synthesis of stereodefined α-alkyl-γ-benzyloxymethyl-β-trimethylsilyl-γ-butyrolactones that serve as an efficient precursor for constructing carbon skeletons having a tertiary or quaternary stereogenic center

The optically active lactone 1 can be transformed to a chiral building block or intermediate for constructing carbon skeletons containing either a tertiary or quaternary stereogenic center by taking advantage of the steric bulk as well as the reactivity of a trimethylsilyl group at the β-position of 1.