One-Pot Synthesis of Fluorescent Alkenylated Benzo[a]imidazo[2,1,5-c,d]indolizine via Tandem Intramolecular Direct C–H Bond Arylation Cyclization/Mizoroki–Heck Reaction

Abstract

We developed a one-pot synthetic method combining stepwise, direct C–H bond arylation cyclization and the Mizoroki–Heck reaction for the efficient synthesis of benzo[a]imidazo[2,1,5-c,d]indolizine fluorescent cores. This method has a broad substrate scope and applies to both electron-donating and electron-withdrawing styrene derivatives. Evaluation of the photophysical properties revealed that the benzoimidazoindolizine fluorophores synthesized by this method exhibited a red-shift of up to 40 nm in absorption and fluorescence compared to previously reported biaryl-type compounds.

Keywords

Pd catalyst - Mizoroki–Heck reaction - Direct C–H bond arylation - Intramolecular cyclization - PHAs

Publication History

Received: 17 November 2025

Accepted after revision: 10 December 2025

Accepted Manuscript online:
11 December 2025

Article published online:
13 January 2026

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