Synergistic Indium and Silver Dual Catalysis: A Regioselective [2 + 2 + 1]-Oxidative N-Annulation Approach for the Diverse and Polyfunctionalized N-Arylpyrazoles

Raju S Thombal; Yong Rok Lee

doi:10.1021/acs.orglett.8b02008

Synergistic Indium and Silver Dual Catalysis: A Regioselective [2 + 2 + 1]-Oxidative N-Annulation Approach for the Diverse and Polyfunctionalized N-Arylpyrazoles

Org Lett. 2018 Aug 3;20(15):4681-4685. doi: 10.1021/acs.orglett.8b02008. Epub 2018 Jul 25.

Authors

Raju S Thombal¹, Yong Rok Lee¹

Affiliation

¹ School of Chemical Engineering , Yeungnam University , Gyeongsan 38541 , Republic of Korea.

PMID: 30044635
DOI: 10.1021/acs.orglett.8b02008

Abstract

Indium(III)/silver(I)-catalyzed [2 + 2 + 1] annulation of arylhydrazine hydrochlorides with β-enamino esters via multicomponent reactions for the construction of diverse and multisubstituted N-arylpyrazoles has been demonstrated. The oxidative cycloaddition proceeds via a cascade triple Michael addition/elimination/air oxidation. This novel protocol provides a rapid and efficient synthetic route to various 3,4-diester-substituted N-arylpyrazoles. The synthesized compounds are further utilized for various synthetic transformations.

Publication types

Research Support, Non-U.S. Gov't