Alkyl- and arylthiodediazoniations of dry arenediazonium o-benzenedisulfonimides. Efficient and safe modifications of the Stadler and Ziegler reactions to prepare alkyl aryl and diaryl sulfides

The reaction between dry arenediazonium o-benzenedisulfonimides 1 and sodiu m thiolates in anhydrous methanol represents an efficient and safe procedur e, of general validity, for the preparation of unfunctionalized or variousl y functionalized alkyl aryl and diaryl sulfides. As a rule, the reaction te mperature was maintained at 0-5 degrees C for the alkylthiodediazoniations and at room temperature (20-25 degrees C) for the alkylthiodediazoniations. The sulfide yields are generally high; of the 63 considered examples, 43 g ave yields greater than 80% and 13 were between 70% and 80% Lower yields we re obtained only when sterically hindered diazonium salts or thiols were us ed. A good amount of the o-benzenedisulfonimide (8) was always recovered fr om the reactions and could be reused to prepare salts 1. The copious experi mental data collected in homogeneous conditions have offered several starti ng points for the study of the mechanism of these reactions.