An easy access to anomeric glycosyl amides and imines (Schiff bases) via transformation of glycopyranosyl trimethylphosphinimides

The preparation and application of anomeric glycosyl phosphinimides in preparative synthesis were studied. Starting from the appropriate glycosyl azides and trialkyl or triaryl phosphines, the corresponding phosphinimides were obtained by modified Staudinger reactions. The latter compounds were readily converted into 1-N-acyl-gluco- and galactopyranosyl amines with high yields by applying activated acid derivatives or simple carboxylic acids. 1-N-Alkylidene- or arylidenephosphinimines (Schiff bases) were obtained by means of aza-Wittig reactions using aliphatic or aromatic aldehydes, respectively. (C) 2001 Elsevier Science Ltd. All rights reserved.