Publication Details (including relevant citation information):
DOI : 10.1021/ol402706a
Published on Web 10/22/2013
ORGANIC LETTERS 2013
Vol. 15, No. 21
Jörg Sedelmeier, Fabio Lima, Alain Litzler, Benjamin Martin and Francesco Venturoni
An efficient and scalable transformation of 3-halo-N-acyl anilines to the corresponding benzoxazoles within a continuous flow reactor is reported. This transformation proceeds via base-mediated deprotonation, ortho-lithiation, and intramolecular cyclization to provide unstable lithiated benzoxazole moieties. The subsequent in-line electrophilic quench results in the formation of substituted benzoxazoles in high yield and quality. Continuous flow technology allowed for accurate temperature control and immediate in-line quench while minimizing the hold-up time for the unstable lithiated intermediates thereby minimizing associated byproduct formation.
Address (URL): http://pubs.acs.org/doi/abs/10.1021%2Fol402706a