A Multistep Flow Process for the Synthesis of Highly Functionalized Benzoxazoles
Accepted version
Peer-reviewed
Repository URI
Repository DOI
Change log
Authors
Sedelmeier, Jörg
Lima, Fabio https://orcid.org/0000-0003-2127-9568
Litzler, Alain
Martin, Benjamin
Venturoni, Francesco
Abstract
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.
Description
Keywords
Aniline Compounds, Benzoxazoles, Catalysis, Cyclization, Molecular Structure, Stereoisomerism
Journal Title
Organic Letters
Conference Name
Journal ISSN
1523-7060
1523-7052
1523-7052
Volume Title
15
Publisher
American Chemical Society (ACS)