Highly Diastereoselective Synthesis and Epoxidation of Chiral 1,2-Dihydronaphthaienes

摘要

Fpoxidations are one of the most important methods for the formation of carbon oxygen bonds. Catalytic enantioseleetive processes, which have been studied particularly intensively, were first developed tor allylic alcohols and have been extended to unfunctionalized olefins in the last few years. The diastereoselective epoxidation of chiral alkenes is also very important with regard to the directing effect of various functional groups. Although epoxidations of monocyclic alkenes have attracted the most attention, the analogous reactions of chiral 1,2-dihydronaphthaienes have not been investigated in detail. This is surprising since achiral dihydronaphthalenes and structurally related chromenes are prime substrates for asymmetric epoxidations. We wereinterested in the synthesis and epoxidation of chiral 1,2-dihydronaphthalenes in the context of the svnthesis of podophvllotoxin analogues.