Synthesis and Transformation of 1-Monosubstituted Tetrazoles to Pyrimidinones, Benzoxazoles and Quinazolinediones Through 1,4-Disubstituted Tetrazolium Salts

Synthesis and some new transformations of 1-aryltetrazoles into other heterocycles through 1,4-disubstituted tetrazolium salts are described. 1-Aryltetrazoles, quaternized with tert-butanol and diacetone alcohol in perchloric acid media, gave pure 1,3- or 1,4-disubstituted tetrazolium salts or their mixtures. 1,3-Disubstituted tetrazolium salts are slowly converted into the corresponding 1,4-salts under dissolving in perchloric acid. 1,4-Disubstituted tetrazolium salts are recyclized to 2-alkylaminobenzoxazoles, 3-monosubstituted 2,4-quinazolinediones and mixtures of di- and tetrahydropyrimidin-2(1H)- ones in basic conditions.