Acid-catalyzed $\mathrm{S_N^H(An)}$ thiolation of p-dihydroxybenzene

The anodic functionalization of p-dihydroxybenzene with poorly nucleophilic thiols is performed by acid activation of p-quinone electrogenerated at the first stage followed by treatment with thiols at the second stage. This two-stage process is preferable in terms of efficiency.