Desymmetrization of meso-cyclic imides via enantioselective monohydrogenation
Satoshi Takebayashi1, Jeremy M John, Steven H Bergens
1Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2.
Abstract:
meso-Cyclic imides are monohydrogenated to form the corresponding hydroxy lactams in 88-97% ee using trans-[Ru((R)-BINAP)(H)(2)((R,R)-dpen)] and related compounds as catalysts with base in THF. The hydrogenation proceeds with high enantiogroup- and chemoselectivity, and it is a desymmetrization reaction, forming up to five stereogenic centers in one reaction. Conversion of a hydroxy lactam into the corresponding iminium ion followed by addition of indene extended the number of stereogenic centers from 5 to 7.
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