Kinetics and Mechanism of Azole n-π*-Catalyzed Amine Acylation.

ABSTRACT: Azole anions are highly competent in the activation of weak acyl donors, but, unlike neutral (aprotic) Lewis bases, are not yet widely applied as acylation catalysts. Using a combination of in situ and stopped-flow ¹H/¹⁹F NMR spectroscopy, kinetics, isotopic labeling, ¹H DOSY, and electronic structure calculations, we have investigated azole-catalyzed aminolysis of p-fluorophenyl acetate. The global kinetics have been elucidated under four sets of conditions, and the key elementary steps underpinning catalysis deconvoluted using a range of intermediates and transition state probes. While all evidence points to an overarching mechanism involving n-π* catalysis via N-acylated azole intermediates, a diverse array of kinetic regimes emerges

SUBMITTER: Dale HJA 

PROVIDER: S-EPMC10436283 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature