Transfer Hydrogenation of β‑Trifluoromethylated Nitroalkenes Catalyzed by Chiral Calcium Phosphate
Tatsuhiro Uchikura1, Yuki Kaneko1, Takanobu Setogawa1
1Department of Chemistry, Faculty of Science, Gakushuin University, Mejiro, Toshima-ku, Tokyo 171-8588, Japan.
Abstract:
We have developed a chiral calcium phosphate-catalyzed transfer hydrogenation of β-trifluoromethylated nitroalkenes. The reaction has a wide substrate scope, giving β-trifluoromethylated nitroalkanes in high yields with high to excellent enantioselectivities (up to 98% ee). Pentafluoroethylated nitroalkene was also a suitable substrate. After the reduction of the nitro group, β-trifluoromethyl amine was synthesized without a loss of enantioselectivity. Chiral 3-trifluoromethyl-2,3-dihydropyrrole derivatives were also synthesized through the intramolecular hydroamination of alkynyl-β-trifluoromethyl amines with high optical purity.
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