The Generation of Difluoroketenimine and Its Application in the Synthesis of α,α‐Difluoro‐β‐amino Amides
作者:Rui Zhang、Zhikun Zhang、Qi Zhou、Lefei Yu、Jianbo Wang
DOI:10.1002/anie.201901591
日期:2019.4.16
Fluorine‐containing β‐amino acids and their derivatives have attracted significant attention due to their importance in life sciences. Herein the previously unknown difluoroketenimine, the analogue of the elusive difluoroketene, has been generated by the reaction of difluorocarbene and isocyanide, which further undergoes [2+2] cycloaddition with imine. The three‐component reaction affords α,α‐difluoro‐β‐amino amides
The simple and selective synthesis of 3-amino-2,2-difluorocarboxylic esters and difluoro-β-lactams using ethyl bromodifluoroacetate in the presence of rhodium catalyst
Treatment of imines (5) with ethyl bromodifluoroacetate (1) and Et2Zn in the presence of RhCl(PPh3)(3) in anhydrous medium gave difluoro-beta-lactams (7) in good to excellent yields, while 3-amino-2,2-difluorocarboxylic esters (6) were obtained in good yields by adding MgSO(4)(.)7H(2)O to the reaction medium. (c) 2005 Elsevier Ltd. All rights reserved.
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