A new efficient methodology for the preparation of 3, 4-difunctionalized pyridine derivatives by an amidoalkylation/Staudinger/aza-Wittig sequence has been developed. The synthesis includes condensation of 3-azidopropanal with urea and p-toluenesulfinic acid followed by reaction of the N-[(3-azido-1-tosyl) propyl] urea obtained with Na-enolates of tosylacetophenone or acetyl acetone to give N-[(5-azido-1-oxo-1-phenyl-2-tosyl) pent-3-yl] ...
