Dynamic asymmetric hemithioacetal transformation by lipase-catalyzed γ-lactonization: in situ tandem formation of 1,3-oxathiolan-5-one derivatives.

Dynamic hemithioacetal systems were efficiently generated in organic solvents and subsequently allowed to react with a range of lipases. This resulted in direct, dynamic asymmetric transformation of the systems, leading to optically active 1,3-oxathiolan-5-one products. The tandem process identified lipase-catalyzed lactonization as a useful method for the resolution of optimal constituents with high chemo- and stereoselectivities.