[2,3]-Sigmatropic rearrangement of ynamides: preparation of α-amino allenephosphonates.
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.
Laboratoire de Synthèse Organique et Méthodologie, ICMMO, UMR CNRS 8182, Bât. 420, Université Paris-Sud, 15 rue Georges Clemenceau, 91405 Orsay Cedex, France.
Filipe
F
Gomes
Antoine
A
Fadel
Nicolas
N
Rabasso