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Updated: Jun 9, 2026

Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
Published on: November 29, 2018
[2 + 2] Photochemical cycloaddition/ring opening of 6-alkenyl-2,3-dihydro-4-pyridones
James J Sahn1, Daniel L Comins
1Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, USA.
Abstract:
During the course of a study aimed at constructing azaspirocycles from 2,3-dihydro-4-pyridones, an unexpected product was obtained in the SET ring-opening reaction of photocycloadduct 1. Differences in reactivity between homologues 1 and 2 were observed in the presence of SmI(2). Tricyclic ketone 2 afforded azaspiro[5.5]undecane 15 when treated with SmI(2); however, when ketone 1 was submitted to similar reaction conditions a double ring-opening/reduction sequence gave cis-piperidinol 10.
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