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Updated: Oct 3, 2026

Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
Published on: November 29, 2018
Solid-State Dynamic Behavior of the Boron-Nitrogen Bond Enables Mechanophotocatalysis of a [2 + 2]-Photocycloaddition
Alaric Shaw1, Peter F Gilbert1, Ivan Bondarenko1
1Department of Chemistry, Reed College, Portland, Oregon 97202-8199, United States.
Abstract:
We report reversible B←N coordinate bond formation and cleavage in the organic solid state. The dynamic behavior was probed using the [2 + 2]-photodimerization of 4-(1-naphthylvinyl)-pyridine (4-nvp) as a chemical reporter under concurrent mechanochemical vortex grinding and ultraviolet light-emitting diode (UV-LED) irradiation. Phenylboronic acid catechol ester (pbe) templates the regio- and stereoselective formation of 1,3-bis-(4-pyridyl)-2,4-bis-(1-naphthyl)-cyclobutane (pncb), and the reaction proceeds efficiently even when pbe is used in substoichiometric amounts (50%, 30% and 5% mol). The catalytic turnover demonstrates that B←N bonds can break and reform dynamically under mechanical stress in the organic solid state, establishing B←N coordination as a design element for responsive molecular materials.
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