Enantioselective organocatalytic amine conjugate addition.
نویسندگان
چکیده
The first enantioselective organocatalytic amine conjugate addition has been successfully developed. The application of LUMO-lowering iminium catalysis has enabled the highly chemo- and enantioselective 1,4-addition of a rationally designed N-silyloxycarbamate nucleophile (HOMO-raised) to alpha,beta-unsaturated aldehydes. Imidazolidinone 2*pTSA was found to catalyze the addition of various orthogonally N-protected silyloxycarbamate nucleophiles to a range of alpha,beta-unsaturated aldehydes, affording synthetically useful beta-amino aldehyde intermediates. The synthetic utility of the protocol was demonstrated in the rapid synthesis of enantioenriched beta-amino acids in one operation and 1,3-amino alcohol derivatives in three operations.
منابع مشابه
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عنوان ژورنال:
- Journal of the American Chemical Society
دوره 128 29 شماره
صفحات -
تاریخ انتشار 2006