Synthesis 2022; 54(22): 5099-5109
DOI: 10.1055/a-1894-8303
paper

Visible-Light-Initiated Oxidative Coupling of Indole and Active Methylene Compounds Using Eosin Y as a Photocatalyst

Ambuj Kumar Kushwaha
,
Suresh Kumar Maury
,
Savita Kumari
,
Arsala Kamal
,
Himanshu Kumar Singh
,
Dhirendra Kumar
,
Ambuj Kushwaha acknowledges the Council of Scientific and Industrial Research (CSIR), New Delhi, India, for Senior Research Fellowship (SRF).


Abstract

A novel, efficient, mild, and inexpensive photocatalytic approach has been established for the visible-light-initiated oxidative coupling of indole and active methylene compounds using atmospheric air and water as an oxidant in the presence of Eosin Y to give 3-methyleneindolin-2-ones. In this work, only one molecule of malononitrile, ethyl acetoacetate, or dimedone reacts with one molecule of indole, but, in contrast, two molecules of barbituric acid react with one molecule of indole. The essential features of this approach are metal-free reaction, high yield of the products, no side product, and use of renewable energy sources.

Supporting Information



Publication History

Received: 03 March 2022

Accepted after revision: 08 July 2022

Accepted Manuscript online:
08 July 2022

Article published online:
08 August 2022

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