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[摘要]：DABCO-catalyzed aza-MBH reactions of N-Boc imines with MVK and EVK have been thoroughly investigated in the paper. The asymmetric version of this aza-MBH reaction was also systematically investigated by using a chiral amine or a chiral phosphane catalyst. It was found that most of the N-protected imines are suitable substrates under the mild reaction conditions and are able to give the corresponding adducts in moderate yields with high ee values. The TQO- or LB1-catalyzed aza-MBH reactions of N-protected alpha-amido-alkyl phenyl sulfones or alpha-amidoalkyl p-tolyl sulfones with MVK could be well conducted, which provides a facile and direct route to obtain highly enantioselective aza-MBH adducts. The Boc protecting group of the aza-MBH product could be easily removed under acidic conditions to give the corresponding alpha-methylene-beta-amino ketone or alpha-methylene-beta-amino alcohol derivatives in good yields. |
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