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Updated: Oct 13, 2025

Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes
Published on: November 21, 2017
Nickel-Catalyzed Annulations of ortho-Haloarylimines
Srinivas Kolluru1, Manvendra Singh1, Bryce Gaskins1
1Department of Medicinal Chemistry, University of Kansas, Lawrence 66045, Kansas.
Abstract:
We report the discovery, development, and mechanism of a nickel-catalyzed annulation reaction between o-haloarylimines and electron-poor olefins. The reaction produces two adjacent anti stereocenters and a free secondary amine. Spirocycles are formed from cyclic imines. We characterized the key oxidative addition intermediate and identified a major path leading to competing homocoupling products. The activation energy of oxidative addition and the rate of oxidative addition complex isomerization were determined. The sensitivity of the reaction to reaction conditions was established in a quantitative manner and both the scope and limitations of the method are presented.
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