Efficient Preparation of ((3-Chloro-2-fluorophenyl)- [7-methoxy-8- (3-morpholin-4-yl-propoxy)-10,11-dihydro-5-oxa-2,4,11-triazadibenzo (a,d)cyclohepten-1-yl]amine) for in vivo Study.

An improved route for the preparation of highly functionalized 5,6-dihydro-pyrimido[4,5-b][1,4]oxazepine 1a in multigram quantities was developed. This new methodology was highlighted by the proper methoxy disposition via a regioselective methylation of 2,4,5-trihydroxy-benzaldehyde followed by a magnesium sulfate-promoted cyclization.