摘要：

Enantioselective 1,4-addition reactions of diethyl-, dimethyl-, and di-n-butylzinc to 6-methylcyclohex-2-enone ( 1 ) and 6-t-butylcyclohex-2-enone ( 4 ), catalyzed by Cu(OTf) 2 and phosphoramidites L1 – L4 were examined. The additions to enone 1 proceeded with high enantioselectivity; by acid- or base-catalyzed epimerization, adduct (S,S)- 2 can be obtained from racemic 1 in diastereo- and enantiomerically pure form. In contrast, Michael additions to substrate 4 were rather slow and could be used for the kinetic resolution of the enone.

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