A Convenient Synthesis of 2‐Sulfanylbenzoselenazole Derivatives via the Reaction of 2‐Lithiophenyl Isothiocyanates with Selenium

The title compounds have been prepared from 2-bromophenyl isothiocyanates 1. Thus, 2-lithiophenyl isothiocyanates 2, obtained from 1 and BuLi through Br/Li exchange, reacted with Se at −78° to form lithium benzoselenazole-2-thiolates 3, which, upon aqueous workup, afforded benzoselenazole-2(3H)-thiones 4. The thiolates 3 were alkylated with reactive alkyl halides and acylated with carboxylic acid chlorides to give 2-(alkylsulfanyl)benzoselenazoles 5 and S-(benzoselenazol-2-yl) thiocarboxylates 6, respectively.