Synthesis of fluorophenothiazines by Smiles rearrangement

1-Chloro-3-fluorophenothiazines have been prepared by Smiles rearrangement of 3-chloro-5-fluoro-2-formamido-2'-nitrophenylsulfides in alcoholic potass ium hydroxide solution. The formyl derivatives were prepared by the formyla tion of the resultant diphenyulsulfides obtained by the condensation of 2-a mino-3-chloro-5-fluorobenzenethiol with o-halonitrobenzenes in ethanolic ac etate solution. 9-Chloro-7-floronitrophenothiazines have been prepared by t he condensation of 2-amino-3-chloro-5-fluorobenzenethiol with o-halonitrobe nzenes containing nitro group (s) or one nitro and halogen atom at both ort ho positions to the reactive halogen atom in ethanolic sodium hydroxide sol ution where Smiles rearrangement occures in situ.