Hydrochloric Acid → 5,6-dimethoxybenzo[d]thiazol-2(3H)-one

Participants

Reaction Steps

19.7 gm (82 mmols) of 5,6-dimethoxy-2-ethoxybenzothiazole were dissolved in 500 ml of ethanol and admixed dropwise at the boiling point with 64 ml of concentrated aqueous hydrochloric acid. After refluxing the mixture for 3 hours, the solvent was evaporated. The residue was recrystallized from methanol. 8.1 gm (48% of theory) of 5,6-dimethoxy-2(3H)-benzothiazolone having a melting point of 191° C. were obtained.

Provenance & Evidence