Optically Active Lithium-Alkoxide Catalyzed Asymmetric Reduction of Imines with Trimethoxyhydrosilane

Abstract

Optically active lithium alkoxide catalyzed asymmetric reduction of imines with trimethoxhydroysilane in moderate enantioselectivity (up to 72% ee).

asymmetric reduction - lithium alkoxide - imine - solvent effect

References

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7 Matsumura et al. reported proline derivatives catalyzed asymmetric reduction with trichlorosilane and moderate enantioselectivity of 66% ee was achieved: Iwasaki F. Onomura O. Mishima K. Kanematsu T. Maki T. Matsumura Y. Tetrahedron Lett.  2001,  42:  2525 

8

We have already found that diastereoselectivity was switched by selection of solvent in the reduction of α,β-epoxyketones. See ref. [4b]