Abstract:
1. Trichloroacetyl isocyanate reacts with the p-CH3- and p-CH3O-substituted and unsubstituted phenylacetylenes and certain tolanes of the 2,4-cycloaddition type, with the formation of 1,3-oxazin-4-one derivatives. 2. A thermographic study of the reaction of trichloroacetyl isocyanate with p-substituted phenylacetylenes revealed that the reactivity of p-substituted phenylacetylenes in the reaction with-trichloroacetyl isocyanate depends on the electronic effect of the substituents. © 1974 Consultants Bureau.