Rearrangement reactions of 1,3,6-triaryl-1,4-dihydro-s-tetrazines leading to 2,4-diarylquinazolines, 1-anilino-3,5-diaryl-1H-1,2,4-triazoles, 1,3,5-triaryl-1H-1,2,4-triazoles, and 2,5-diaryl-1H-1,3,4-oxadiazoles. X-Ray structure determination of 6-isopropyl-2,4-diphenylquinazoline

Abstract

1,3,6-Triaryl-1,4-dihydro-s-tetrazines (2c–g) rearrange on heating at ca. 200 °C to 2,4-diaryl-quinazolines (for which an X-ray determination was carried out on the 6-isopropyl compound) and 1-anilino-3,5-diaryl-1H-1,2,4-triazoles as major products. Hydrolysis in chloroform solution of the title compounds (2) and their 1 -alkyl analogues gives rise to 1 -aryl (or alkyl)-3,5-diaryl-1H-1,2,4-triazoles and 2,5-diaryl-1,3,4-oxadiazoles.