Catalytic Synthesis of 5-Fluoro-2-oxazolines: Using BF3·Et2O as the Fluorine Source and Activating Reagent

ACS Omega. 2022 Jun 1;7(23):19988-19996. doi: 10.1021/acsomega.2c01791. eCollection 2022 Jun 14.

Abstract

Hypervalent iodine catalyst-catalyzed nucleophilic fluorination of unsaturated amides using BF3·Et2O as the fluorine source and activating reagent was reported. Various 5-fluoro-2-oxazoline derivatives were synthesized in good to excellent yields (up to 95% isolated yield) within 10 min. The process was efficient and metal-free under mild conditions. A mechanism involving a fluorination/1,2-aryl migration/cyclization cascade was proposed on the basis of previous work and experimental results.