One-Pot Synthesis of 3,5-Disubstituted 1,2,4-Oxadiazoles Directly from Nitrile and Hydroxylamine Hydrochloride Under Solvent-Free Conditions Using Potassium Fluoride as Catalyst and Solid Support

Abstract

A one-pot synthesis of 3,5-disubstituted 1,2,4-oxadiazoles with two identical substituents directly from the reaction of nitriles and hydroxylamine hydrochloride in the presence of potassium fluoride as catalyst and solid support under solvent-free condition is described. Moreover, the formation of products has been discussed, and a plausible mechanism has been presented. Simplicity of the process, workup in aqueous media, and excellent yields are some advantages of this method.

Keywords:

• Amidoximes
• nitriles
• one-pot reaction
• 1,2,4-oxadiazole
• potassium fluoride
• solvent-free condition

ACKNOWLEDGMENT

The authors gratefully acknowledge the Research Council of K. N. Toosi University of Technology for partial financial support of this work.

Notes

^a All reactions were performed at 100 °C for 12 h.

^b Isolated yields.

^c 1 h after the reaction.

^a All reactions were performed with 2 mmol nitrile, 2 mmol hydroxylamine hydrochloride, and 1 g potassium fluoride at 100 °C for 12 h.

^b Isolated yields.