[2,3]-Sigmatropic rearrangement of ynamides: preparation of α-amino allenephosphonates
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Updated: May 21, 2026

Preparation of N-(2-alkoxyvinyl)sulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines
Published on: January 3, 2018
Filipe Gomes1, Antoine Fadel, Nicolas Rabasso
1Laboratoire de Synthèse Organique et Méthodologie, ICMMO, UMR CNRS 8182, Bât. 420, Université Paris-Sud, 15 rue Georges Clemenceau, 91405 Orsay Cedex, France.
Abstract:
α-Amino allenephosphonates were easily prepared in two steps from protected amines, propargyl alcohols, and chlorophosphites. First, ynamides were synthesized from unprotected 1-bromopropargyl alcohols using a copper(II) catalyzed coupling reaction. In the second step, the previously prepared ynamides were transformed directly to allenes through a [2,3]-sigmatropic rearrangement of propargyl phosphites. This efficient method led to the formation of a series of α-amino allenephosphonates with diverse substituents on the amine, the phosphonate, and the allene moieties.
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