Chitosan-SO₃H (CTSA) an efficient and biodegradable polymeric catalyst for the synthesis of 4,4′-(arylmethylene)bis(1H-pyrazol-5-ol) and α-amidoalkyl-β-naphthol’s

Abstract

An efficient, green procedure for the synthesis of 4,4′-(arylmethylene)bis(1H-pyrazol-5-ol) and α-amidoalkyl-β-naphthol’s using biodegradable polymeric catalyst chitosan-SO₃H (CTSA), is operationally easy to prepare by mixing chitosan and chlorosulfonic acid. This catalyst displays excellent catalytic activity and reusable for five subsequent reactions without significant loss of catalytic activity. This protocol proceeds with short reaction times, at mild temperatures, in a solvent-free reaction, and generally with high yields. We present herein a practical, efficient and simple procedure with a broad substrate scope that allows access to two different reactions 1H-pyrazole-5-ol and α-amidoalkyl-β-naphthol’s core unit.

Graphical Abstract

Keywords:

• 4,4′-(arylmethylene)bis(1H-pyrazol-5-ol) arens
• α-amidoalkyl-β-naphthol’s arens
• biodegradable polymeric catalyst
• CS-SO3H
• solid acid catalyst

Acknowledgments

The authors are thankful to IIT Mandi Himachal Pradesh for providing analytical facilities. We also gratefully acknowledge the School of chemical Science K.B.C.N.M.U for providing all necessary facilities.

Disclosure statement

No conflict of interest was reported by the author(s).