76356-13-3Relevant articles and documents
The Meisenheimer Rearrangement in Heterocyclic Synthesis. II. Synthesis and X-Ray Crystal Structure of a Tetrahydro-1H-2,3-benzoxazocine and Preparation of a Hexahydro-2,3-benozoxazonine
Bremner, John B.,Browne, Elaine J.,Davies, Peter E.,Raston, Colin L.,White, Allan H.
, p. 1323 - 1334 (2007/10/02)
The heterocyclic derivatives, 8,9-dimethoxy-3-methyl-1-phenyl-3,4,5,6-tetrahydro-1H-2,3-benzoxazocine (3a) and 9,10-dimethoxy-3-methyl-1-phenyl-1,3,4,5,6,7-hexahydro-2,3-benzoxazonine (3b), examples of two new ring systems, have been prepared by Meisenheimer rearrangement of the corresponding 2-benzazepine and 2-benzazocine N-oxide derivatives (2a) and (2b).The Bischler-Napieralski-type cyclization reaction was used in the preparation of the tertiary amine precursors of these N-oxides; reaction conditions for the cyclization were critical and phosphorus oxychloride inrefluxing butanenitrile was found to give the best yields of the seven- or eight-membered cyclic imine intermediates.Reductive cleavage of the benzoxazocine derivative (3a) with zinc in acetic acid followed by N-methylation gave the expected product, -4,5-dimethoxyphenyl>phenylmethanol (12).The crystal and molecular structure of (3a) has been determined by X-ray crystallographic analysis.
