Dithiobenzoic acid is the organosulfur compound with the formula C6H5CS2H. It is a dithiocarboxylic acid, an analogue of benzoic acid, but more acidic and deeply colored.
Synthesis and reactions
It can be prepared by sulfiding benzal chloride: C6H5CCl3 + 4 KSH → C6H5CS2K + 3 KCl + 2 H2S C6H5CS2K + H+ → C6H5CS2H + K+
It also arises by the reaction of the Grignard reagent phenylmagnesium bromide with carbon disulfide, followed by acidification: C6H5MgBr + CS2 → C6H5CS2MgBr C6H5CS2MgBr + HCl → C6H5CS2H + MgBrCl
It is about 100x more acidic than benzoic acid. Its conjugate base, dithiobenzoate, undergoes S-alkylation to give dithiocarboxylate esters. Similarly, dithiobenzoate reacts with "soft" metal salts to give complexes, e.g. Fe(S2CC6H5)3 and Ni(S2CC6H5)2.
Chlorination of dithiobenzoic acid gives the thioacyl chloride C6H5C(S)Cl.