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Updated: Jun 13, 2026

Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes
Published on: November 21, 2017
A general strategy for regiocontrol in nickel-catalyzed reductive couplings of aldehydes and alkynes
Hasnain A Malik1, Grant J Sormunen, John Montgomery
1Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109-1055, USA.
Abstract:
A strategy for catalyst-controlled regioselectivity in aldehyde-alkyne reductive couplings has been developed. This strategy is the first where either regiochemical outcome may be selected for a broad range of couplings, without relying on substrate biases or directing effects. The complementary use of small cyclopropenylidene carbene ligands or highly hindered N-heterocyclic carbene ligands allows the regiochemical reversal with unbiased internal alkynes, aromatic internal alkynes, conjugated enynes, or terminal alkynes.
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