(1H-Benzotriazol-1-yloxy)tris(dimethylamino)phosphonium Hexafluorophosphate- and (1H-Benzotriazol-1-yloxy)tripyrrolidinophosphonium Hexafluorophosphate-Mediated Activation of Monophosphonate Esters: Synthesis of Mixed Phosphonate Diesters, the Reactivity of the Benzotriazolyl Phosphon...

Article abstract of DOI:10.1021/jo00121a045

A general method for synthesizing mixed phosphonate diesters from monoesters using (1H-benzotriazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate or (1H-benzotriazol-1-yloxy)tripyrrolidinophosphonium hexafluorophosphate reagents is described.The reaction proceeded through a benzotriazolyl ester as shown by comparison with other reagents such as DCC, DCC/DMAP, DCC/1-hydroxybenzotriazole, bromotris(dimethylamino)phosphonium hexafluorophosphate, or O-(1H-benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium hexafluorophosphate and by 31P NMR analysis.This benzotriazolyl phosphonic ester intermediate was more reactive toward alcohols than toward amines, contrary to its carboxylic analogue.