Asymmetric Synthesis of α-and β-Benzylhydroxy-γ-butyrolactones

Herein we describe a new asymmetric synthesis of α-benzyl-α-hydroxy-γ-butyrolactone, a core building block of new HIV-1 protease inhibitors containing a tertiary alcohol in the transition-state mimic. Immediate access to γ-benzyl-β-hydroxy-γ-butyrolactone is also possible from a common intermediate. Both lactones are useful building blocks in their own right.