A facile and environmentally benign access to N-aryl/alkyl-4H-benzoxazin-2-amines is achieved from 1-[2-(hydroxymethyl)phenyl/alkyl]-3-phenylthioureas under transition-metal-free conditions. The conversions occur smoothly in the presence of a catalytic amount of molecular iodine and hydrogen peroxide as the oxidant in tetrahydrofuran at room temperature to afford moderate to good yields (28–90%) of
Synthesis of 2-amino-4h-3,1-benzoxazines from diphenyl cyanocarbonimidate. facile replacement of the n-cyanoimine function by nitrogen nucleophiles
作者:Peter J. Garratt、Christopher J. Hobbs、Roger Wrigglesworth
DOI:10.1016/0040-4020(89)80113-9
日期:1989.1
The reaction of 2-aminobenzylalcohol (2) with diphenylcyanocarbonimidate (1) gave 2-N-cyanoimino-4H-3,1-benzoxazine (3). The cyanoimino group can be readily replaced by amines to give a variety of 2-amino-4H-3,1-benzoxazines.