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[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
The photochemistry of 4-azidopyridine-1-oxide
Katherine J Hostetler1, Kyle N Crabtree, James S Poole
1Department of Chemistry, Ball State University, Muncie, Indiana 47306, USA.
Abstract:
Laser flash photolysis of 4-azidopyridine-1-oxide at 266 or 308 nm yields triplet 4-nitrenopyridine-1-oxide as the dominant reactive intermediate species, with k(ISC) of approximately 2 x 10(7) s(-1). No evidence of products arising from the singlet nitrene was observed, indicating a slow rate of cyclization to the benzazirine and didehydroazepine species. The slow rate of cyclization is postulated to be due to the aminoxyl-like electronic configuration of this species, which withdraws spin density from sites for potential cyclization.
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