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Updated: Nov 2, 2025

Light-driven Enzymatic Decarboxylation
Published on: May 22, 2016
Visible-light-driven spirocyclization of epoxides via dual titanocene and photoredox catalysis
Shuangjie Lin1, Yuqing Chen1, Fusheng Li1
1Zhang Dayu School of Chemistry, State Key Laboratory of Fine Chemicals, Dalian University of Technology Dalian 116024 China shilei17@dlut.edu.cn.
Abstract:
We describe the synergistic utilization of titanocene/photoredox dual catalysis driven by visible light for the radical opening/spirocyclization of easily accessible epoxyalkynes. This environmentally benign process uses the organic donor-acceptor fluorophore 2,4,5,6-tetra(9H-carbazol-9-yl)isophthalonitrile (4CzIPN) as a photocatalyst and Hantzsch ester (HE) as an electron donor instead of stoichiometric metallic reductants. The photocatalytic conditions showed exceptionally high reactivity for the synthesis of privileged and synthetically challenging spirocycles featuring a spiro all-carbon quaternary stereocenter. Cyclic voltammetry (CV) studies suggest that Cp2TiIIICl is the catalytically active species.
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