Chitosan-SO <sub>3</sub> H (CTSA) an efficient and biodegradable polymeric catalyst for the synthesis of 4,4′-(arylmethylene)bis(1 <i>H</i> -pyrazol-5-ol) and α-amidoalkyl-β-naphthol’s
Paresh G. Patil, Suman Sehlangia, Dhananjay H. More
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.