希土類複核錯体触媒を用いたO-メチルヒドロキシルアミンの不斉共役付加反応

摘要

The asymmetric conjugate addition reaction of O-alkylhydroxylamine is one of the attractive strategies to afford not only the beta-amino carbonyl compounds but also functionalized aziridine derivatives. We found that our Yttrium-Lithium-tris(Binaphthoxide) complex [(S)-YLB (1)] catalyzed the conjugate addition of 3 toward 2 to afford the Michael adduct 4 in high chemical yield (up to 98 percent yield) and high enantiomeric excess (up to 97 percent ee). Water contaminant decreased reactivity very much, so DRIERITE~R, a neutral desiccant, was added. Catalyst loading was reduced to 0.5 mol percent (95 percent yield, 96 percent ee). Mechanism of the reaction was also investigated.