Reactions of 1λ5σ4,2,4-triazoline-3,5-dione decomposition products with organophosphorus nucleophiles

Abstract

The reactions of 1,1-dialkyl-4-t-butyl-1λ⁵σ⁴,2,4-triazoline-3,5-diones, under conditions known to produce N-isocyanato dialkylamines and t-butyl isocyanate, with various phosphorus compounds have been investigated. With phosphonium ylides the products depend on the phosphonium compound; highly stable or highly reactive ylides give products derived from t-butyl isocyanate, whereas ylides of intermediate stability react with the N-isocyanato-amine. The former products were independently synthesised from the phosphonium ylide and t-butyl isocyanate. Reactions with iminophosphoranes gave carbodi-imides, but only through reaction with t-butyl isocyanate; in no case were products derived from reaction with N-isocyanato-amine obtained. No evidence was observed for reaction with either N-isocyanato-amine or t-butyl isocyanate in experiments with a variety of phosphorus(III) compounds.