Weinreb amides in carbene chemistry: a time-resolved IR investigation into a potential intramolecular stabilization mechanism.
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.
Evans
Anthony S
AS
Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, USA.
Sundaram
G S M
GS
Sassmannshausen
Jörg
J
Toscano
John P
JP
Tippmann
Eric M
EM