UNEXPECTED STAUDINGER REACTION OF ALPHA-AZIDOACETONITRILES ALPHA-PHENYL SUBSTITUTED WITH TRIPHENYLPHOSPHINE - PREPARATION, X-RAY CRYSTAL AND MOLECULAR-STRUCTURES OF A PHOSPHAZINE, AN AMINOPHOSPHONIUM CARBANIONSALT AND A PHOSPHAZIDE, WITH (Z)-CONFIGURATION

Staudinger reaction of alpha-azidophenylacetonitrile with triphenylpho sphine in 1:2 molar ratio provides the triphenylphosphazine 4 derived from alpha-diazophenylacetonitrile, whereas in 2:1 molar ratio the fin al product is found to be the aminotriphenylphosphonium salt of phenyl malononitrile 6. However, the Staudinger reaction of alpha-azidodiphen ylacetonitrile with triphenylphosphine affords the corresponding (Z)-p hosphazide 17. The crystal and molecular structures of compounds 4, 6, and 17 have been determined by X-ray analysis. Compound 17 is the fir st isolated phosphazide which presents the (Z)-configuration with resp ect to the central N-N bond of the PN3C moiety (P-N-N-N=0.0(3)degrees) . Copyright (C) 1996 Elsevier Science Ltd