| abstract |
A process for the preparation of diarylsulphides or of diarylselenides of the general formulae Ar - X - Ar, where X = S or Se and Ar = aryl, by the action of sulphur and sulphur dioxide or of selenium and selenium dioxide on a product of the formula Ar - H. Application to the preparation of the phenothiazines of the formula <IMAGE> (where X = S or Se and Z and Z1, which may be identical or different, = hydrogen, halogen, alkyl or alkoxy). |