Phosphorus–nitrogen compounds. Part XLII. Reactions of PPP-triphenyiphosphazene with organic acid halides and mononuclear phosphorus halides

Abstract

PPP-Triphenylphosphazene, Ph₃PNH (tpp), reacts with simple acyl halides in benzene to afford excellent yields of N-acylmonophosphazenes and aminotriphenylphosphonium halide. Triphenylphosphazenyl-sym-triazines can also be prepared but no more than two Ph₃PN moieties can be introduced by this route. The ease of replacement of halogen by triphenylphosphazenyl is very dependent on the nature of the other groups present in the halide substrate, the Ph₃PN group exerting a much more powerful retarding effect than most other substituents. Thiophosphorus(V) halides react similarly to chloro-sym-triazines and the same substituent effect is noted. With phosphorus(III) halides, only one triphenylphosphazenyl group has been introduced by this route. Chloramination of diphenyl(triphenpyphosphazenyl)phosphine affords a hydrolytically stable diphosphazenium chloride, which may be converted into a previously reported phosphazenium bromide which had been incorrectly assigned a triphosphazenium structure.