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Updated: Oct 4, 2025

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Cascade cyclization for the synthesis of indolo[2,1-α]isoquinoline derivatives via visible-light-induced
Na Ma1, Lin Guo1, Zheng-Jia Shen1
1State Key Lab of Urban Water Resource and Environment, School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China. xyyang@hit.edu.cn.
Abstract:
A transition metal-free photoredox cascade cyclization is herein reported. In this protocol, sustainable visible light was used as the energy source and organic light-emitting molecule eosin Y served as an efficient photocatalyst. A variety of easily available 2-aryl-N-acryloyl indoles can readily react with alkyl radicals, which are generated from organohalides and tertiary amines via either the halogen-atom-transfer (XAT) or the hydrogen-atom-transfer (HAT) process, furnishing the desired indolo[2,1-α]isoquinoline derivatives in good to moderate yields. This protocol features broad substrate scope and good functional group tolerance under mild conditions.
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