New method for the preparation of dibenzo[b, f][1,4]thiazepines
Abstract
The S-amination of 9H-thioxanthen-9-ol (2a) and 9-substituted derivatives 2b–e (Me (b), Et (c), iPr (d), Ph (e)) with O-mesitylenesulfonylhydroxylamine (MSH) was carried out. The expected product, 10-amino-9-hydroxy-9-isopropyl-9H-thioxanthenium mesitylenesulfonate (3d), was obtained in 78(%) yield from the corresponding thioxanthen(9)-ol 2d. However, in the case of 2a–c and 2e the reaction led instead to dibenzo[b,f][1,4]thiazepines 6a–c and 6e in moderate yields. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:246–250, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20010