Synthesis of some new N,N′-diarylsubstituted methylene-bis-dihydro-2H-1,3-benzoxazines

The synthesis of a new series of six-membered N,N'-diarylsubstituted methylene-bis-dihydro-2H- 1,3-benzoxazines (5a-e) was achieved in excellent yields by Mannich-type condensation of N, N'-diarylsubstituted methylene-bis-o-hydroxybenzyl amines (4a-e) with formaldehyde in chloroform at reflux. These amines (4a-e) were obtained by the reduction of N, N'-diarylsubstituted methylene-bis-o-hydroxybenzyl imines (3a-e) with NaBH4, which inturn were obtained by the condensation of methylene-bissalicylaldehyde (2) with various substituted arylamines. (c) 2008 Cherkupally Sanjeeva Reddy. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.