Résumé
Diaminophosphonium diazaylides
2 react under mild conditions with diphenylacetyl chloride, to afford diphenyl-
N-(substituted)ketenimines
4 or, depending on the case, their transformation products: either the tautomer
8, or the dimer
9. The general reaction seems to proceed firstly via an elimination step on the acid chloride followed then by an aza-Wittig reaction between the resulting ketene
7 and the diaminophosphonium monoazaylide
6.