Amidation of α-Amino Acids Using Dichloro(methyl)(3,3,3-trifluoropropyl)silane and Imidazole without Conventional Protection and Deprotection of α-Amino Group

Abstract

Amidation of amino acids using dichloro(methyl)(3,3,3-trifluoropropyl)silane (MTFPSCl₂) and imidazole is described. MTFPSCl₂ activates the carboxy group and protects the α-amino group of amino acids. The amidation proceeded with 19 amino acids and 19 amines, including α-branched amines and anilines; the corresponding amino acid amides were synthesized in good-to-high yields (up to 96%) with low-to-no racemization.

Key words

amidation - unprotected amino acid - coupling reagent - silyl reagent - dichloro(methyl)(3,3,3-trifluoropropyl)silane

Publication History

Received: 28 April 2022

Accepted after revision: 31 May 2022

Accepted Manuscript online:
31 May 2022

Article published online:
22 June 2022

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