Unusually long lifetimes of the singlet nitrenes derived from 4-azido-2, 3, 5, 6-tetrafluorobenzamides

…, SY Chan, R Floresca, K Rajagopalan…

Index: Marcinek, Andrzej; Platz, Matthew S.; Chan, Stephen Y.; Floresca, Rey; Rajagopalan, Krishnan; et al. Journal of Physical Chemistry, 1994 , vol. 98, # 2 p. 412 - 419

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Citation Number: 45

Abstract

Laser flash photolysis (308 nm, 20 ns, 150 mJ) of 4-azido-2, 3, 5, 6-tetrafluorobenzamides, esters, and thioesters generates singlet nitrenes which can be intercepted with pyridine to produce strongly absorbing ylides. It was possible to resolve the rate of formation of the ylides as a function of pyridine concentration. This has led to direct measurements of the absolute rate constants of (a) the reaction of the nitrene with pyridine,(b) ring expansion of ...