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

Publikationsverlauf

Eingereicht: 28. April 2022

Angenommen nach Revision: 31. Mai 2022

Accepted Manuscript online:
31. Mai 2022

Artikel online veröffentlicht:
22. Juni 2022

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Copper-catalyzed syntheses of amino acid anilides from unprotected amino acid amides with iodobenzenes have been reported:
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