Aziridines. 27. The Synthesis and Reactions of 4-Aroyltetrahydro-2H-1,2,4-oxadiazines

2-Aryl- or 2-alkyl-4-aroyltetrahydro-2H-1,2,4-oxadiazines have been prepared by heating 1-aroylaziridines and nitrones in toluene or m-xylene. In hot acetic acid 2-(p-tolyl)-3-phenyl-4-(3,5-dinitrobenzoyl)tetrahydro-2ff-1,2,4-oxadiazine (6) is converted into a mixture of p-azotoluene, p-azoxytoluene, benzaldehyde and -(β-hydroxyethyl)-3,5-dinitrobenzamide. 6 reacts with p-nitrotoluene in concentrated sulfuric acid to give 2-methyl-5-nitro-4′-aminodiphenylmethane, Ar-(d-hydroxyethyD-3,5-dinitrobenzamide, and benzaldehyde. In hot basic solution 2-(p-tolyl)-3-phenyl-4-(p-nitrobenzoyl)tetrahydro-2H-1,2,4-oxadiazine (5) isomerizes into N-(p-tolyl)-β- (p-nitrobenzamido)ethylbenzimidate (17). Reduction of 6 leads to A′-benzyl-p-toluidine and thermolysis of 6 at 200° causes vigorous decomposition and formation of AI-benzal-p-toluidine.