Stereospecific synthesis of [gamma]-butyrolactones from acyclic vinyl sulfoxides: an asymmetric synthesis of optically pure oak lactones

The sulfoxide-directed lactonization of several trisubstituted vinyl sulfoxides with dichloroketene proceeds in a completely stereospecific manner. The lactonization of (E) -3 (R) --tolylsulfinyloctene occurs with complete enantiospecificity to produce a precursor for the synthesis of optically pure oak lactones.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25937/1/0000500.pd

The diastereoselective Meth-Cohn epoxidation of camphor-derived vinyl sulfones

Some camphor-derived vinyl sulfones bearing oxygen functionality at the allylic position have been synthesized and their nucleophilic epoxidation reactions under Meth-Cohn conditions have been explored. The γ-oxygenated camphor-derived vinyl sulfones underwent mildly diastereoselective nucleophilic epoxidation reactions, affording the derived sulfonyloxiranes in up to 5.8:1 dr. The observed diastereoselectivities were sensitive to the reaction conditions employed. In contrast, no stereoselectivity was observed in the nucleophilic epoxidation of the corresponding γ-oxygenated isobornyl vinyl sulfone. A tentative mechanism has been proposed to explain the origins of the diastereoselectivit