A multistep flow process for the synthesis of highly functionalized benzoxazoles.
作者： Jörg Sedelmeier , Fabio Lima , Alain Litzler , Benjamin Martin , Francesco Venturoni
DOI: 10.1021/OL402706A
关键词: Intramolecular cyclization 、 Continuous flow 、 Chemistry 、 Flow process 、 Yield (chemistry) 、 Electrophile 、 Benzoxazole 、 Deprotonation 、 Combinatorial chemistry
摘要: An efficient and scalable transformation of 3-halo-N-acyl anilines to the corresponding benzoxazoles within a continuous flow reactor is reported. This proceeds via base-mediated deprotonation, ortho-lithiation, intramolecular cyclization provide unstable lithiated benzoxazole moieties. The subsequent in-line electrophilic quench results in formation substituted high yield quality. Continuous technology allowed for accurate temperature control immediate while minimizing hold-up time intermediates thereby associated byproduct formation.
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