Preparation of Mesoporous Silica-Supported Chiral AminoudAlcohols for the Enantioselective Addition of Diethylzinc toudAldehyde and Asymmetric Transfer Hydrogenation to Ketones

摘要

Optically active (−)-ephedrine, (−)-norephedrine, and (−)-prolinol were immobilized onto cubicmesoporousMCM-48 silica. The immobilized amino alcohols served as a heterogeneous chiral catalyst for the asymmetric addition of diethylzinc to aldehydes and transfer hydrogenation to ketones. The developed catalytic process yielded optically enriches secondary aromatic alcohols with 92–99% conversion and 70–82% enantioselectivity.