Evolution of chiral Lewis basic N-formamide as highly effective organocatalyst for asymmetric reduction of both ketones and ketimines with an unprecedented substrate scope
作者:Li Zhou、Zhouyu Wang、Siyu Wei、Jian Sun
DOI:10.1039/b703307a
日期:——
L-Pipecolinic acid derived Lewis basic N-formamide has been developed as a first highly effective catalyst for the asymmetric reduction of aromatic and aliphatic ketones as well as aromatic and aliphatic ketimines in good to high enantioselectivity.
asymmetric reduction of N-unsubstituted β-enamino esters with trichlorosilane as the reducing agent. The steric hindrance of silyl ether substitutes can remarkably influence the catalytic performance. The optimized triphenylsilyl substituted catalyst 2k can efficiently catalyze the reduction reaction, affording enantioenriched β-amino ester with excellent yield (95 %) and high ee (82 %).