A mild and metal-free synthesis of chiral 2,3-dihydro-3-hydroxymethyl-1,4-benzoxazines

Tandem Amination/Oxetane Ring Opening toward Benzomorpholines

Herein, a tandem approach that allows rapid access to the benzomorpholine scaffold is reported. This operationally simple method allows for valuable heterocycles to be isolated in moderate to high yields. The overall transformation consists of an initial C-N coupling, demonstrated using traditional Ullmann or Buchwald-Hartwig conditions, followed by an in situ oxetane ring opening. A range of functionality is tolerated on the aryl ring, and the cyclization exposes a pendant hydroxymethyl substituent, providing opportunities for further functionalization.