The reaction of 2,2-dimethyl-3-phenylazirine with N-phthalylglycine acid chloride gives initially N-acyl-3-chloroaziridine, which undergoes isomerization to a substituted 2-oxazoline and the corresponding keto amide. The reaction of 2,2-di-methyl-3-phenylazirine with the chlorides of crotonic, β- (2-furyl) acrylic, cinnamic, and phenylpropiolic acids in benzene at 20 °C leads to 2,2-dimethylindoxyl and the corresponding unsaturated acid.