Remarkably Low Catalyst Loading in Brønsted Acid Catalyzed Transfer Hydrogenations: Enantioselective Reduction of Benzoxazines, Benzothiazines, and Benzoxazinones

Abstract

A highly efficient transfer hydrogenation of benzoxazines, benzothiazines, and benzoxazinones with as low as 0.01 mol % binol phosphate catalyst furnishes the dihydro-2H-benzoxazines, -benzothiazines, and -benzoxazinones in good yields and with excellent enantioselectivities (see scheme). Particularly noteworthy are the mild reaction conditions and the wide scope of substrates, including sulfur-containing compounds. Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2002/2006/z601832_s.pdf or from the author. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.