InBr3-catalyzed direct alkynylation of nitrones with terminal alkynes: an efficient synthesis of N-hydroxy-propargyl amines
作者:Du-Ming Ji、Ming-Hua Xu
DOI:10.1016/j.tetlet.2009.03.206
日期:2009.6
An InBr3-Catalyzed direct and efficient alkynylation of nitrones with terminal alkynes was developed. The process enables practical synthesis of a wide range of synthetically useful N-hydroxy-propargyl amine derivatives in good yields under mild conditions. The application of this method to optically active propargylic N-hydroxyamines syntheses was also described. With chiral nitrones, good diastereoselectivities were obtained. Moreover, the first chiral indium(III) complex-catalyzed asymmetric alkynylation of nitrone was achieved with moderate enantioselectivity. (C) 2009 Elsevier Ltd. All rights reserved.
A Lewis acid/metal amide hybrid as an efficient catalyst for carbon–carbon bond formation
synthetically useful propargyl hydroxylamines. It is noted that neither the Lewis acids (InCl3, In(OTf)3) nor the metal amides (In(HMDS)3) have activity; only the hybrids worked well, and the catalytic activity of the hybrids was shown to be much higher than that of previously reported catalysts for this reaction. The concept of a Lewis acid/metal amide hybrid as a catalyst may be expanded to broad acid/base