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Updated: Aug 23, 2026

Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
Published on: November 29, 2018
Access to an excited state via the thermal ring-opening of a cyclopropylidene
Matthew E Cremeens1, Barry K Carpenter
1Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301, USA.
Abstract:
[reaction: see text] Thermal generation of singlet excited states is unusual in organic chemistry. The potential energy surface for the thermal ring-opening of 4-methylene-bicyclo[3.1.0]hex-2-ene-6-ylidene (1) was calculated at the CASSCF level of theory and found to produce alpha,3-didehydrotoluene in its biradical ground state (S(0)) and/or its zwitterionic excited state (S(1)).
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