One-Pot Synthesis of 1,2-Disubstituted Indoles from 2-Ethynylanilines and Benzaldehydes
Jie Ma1, Xi Wang1, Er-Jun Hao2
1School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan 430205, China.
Abstract:
An efficient synthesis of a variety of 1,2-disubstituted indoles from 2-ethynylanilines was developed. Using 2-ethynylanilines and benzaldehydes as starting materials, the target products (1,2-disubstituted indoles) were obtained smoothly through condensation, reduction, and subsequent cyclization. Various functional groups attached to the aryl ring of 1,2-disubstituted indoles were well tolerated. The protocol features easy performance, easily available starting materials, good yield, and a broad substrate scope, showing potential synthetic value for the preparation of a variety of biologically or pharmaceutically active compounds.
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