MOLECULAR REARRANGEMENT OF SULFUR COMPOUNDS. PART V: PYROLYSIS OF MERCAPTOOXADIAZOLE DERIVATIVES

Abstract

Pyrolysis of 5-phenyl-2-benzylthio-1,3,4-oxadiazole (1) by heating at ca. 250°C in a sealed tube gives rise to CO₂, H₂S, H₂O, benzyl thiocyanate, benzonitrile, benzyl sulfide, aniline, benzamide, benzaldehyde, 2-mercaptoquinazolinone, dibenzyl, stilbene, and tetraphenylthiophene. Furthermore pyrolysis of 5-phenyl-2-phenacylthio-1,3,4-oxadiazole (9) gives analogous results, besides phenancyl thiocyanate. Pyrolysis of 5(2-hydroxyphenyl)-2-benzylthio-1,3,4-oxadiazole (11) gives 2-hydroxybenzonitrile, 5(2-hydroxyphenyl)-1,3,4-oxadiazole-2-thiol, and 2-hydroxybenzamide, in addition to the previous obtained results. The mechanism of these results has been discussed.

Key Words:

• Molecular rearrangement
• Pyrolysis
• mercaptooxadiazoles.