Conversion of 5-Aryl-3-phenylthio-2(3H)-furanones into Some Nitrogen- and Sulphur-Containing Heterocycles

Abstract

3-Phenylthio-5-aryl-2(3H)-furanones 4 were prepared from 2-phenylthio- 3-aroylpropionic acids 3 by a ring closure using acetic anhydride. Benzylamine reacted with 4 to give the benzylamide derivatives 5, which were cyclized to the corresponding 2(3H)-pyrrolones 6. The isothiazolone derivatives 7 were obtained from the benzylamides 5 by the action of SOCl₂. A ring opening of furanone 4 with hydrazine hydrate gave the acid hydrazides 8. The latter hydrazides were utilized as starting materials for the synthesis of pyridazinone derivatives 9 and 11, 1,3,4-oxadiazoles 13, and triazolone derivatives 14.

Keywords:

• 2(3H)-furanones
• 1,3,4-oxadiazales
• 2(3H)-pyrrolones
• pyridazinones
• 1,2,4-triazolones