Weinreb amides in carbene chemistry: a time-resolved IR investigation into a potential intramolecular stabilization mechanism
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Updated: Jun 8, 2026

Characterizing Lewis Pairs Using Titration Coupled with In Situ Infrared Spectroscopy
Published on: February 20, 2020
Anthony S Evans1, G S M Sundaram, Jörg Sassmannshausen
1Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, USA.
Abstract:
A chloromethylhydroxamiccarbene was generated photochemically in an attempt to form an intramolecularly stabilized carbene. A rapidly formed intermediate at 1645 cm(-1) decayed with an observed rate of 1.99 × 10(6) s(-1). Other intermediates were also observed. These also decayed, albeit much more slowly (k(obs) = 3.47 × 10(3) and 1.98 × 10(4) s(-1)). Multiple intermediates are apparently a function of both the proximal N,O-dimethylhydroxamic ester and multiple conformers of both the carbene and precursor.
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