2-Hydroxybenzothiazole (2-OHBT) is a 2-substituted benzothiazole. It is a tautomer of 2-benzothiazolinone. Its enthalpy of formation in the gas phase has been determined using high-level ab initio molecular orbital calculations at the G3(MP2)//B3LYP level of theory. Polarized IR spectra of the hydrogen-bonded molecular crystals of 2-OHBT have been studied. Oxidation of 2-OHBT using H2O2/UV and iron(III) photoassisted Fenton techniques have been reported. 2-OHBT is released into wastewaters during the industrial production of 2-mercaptobenzothiazole, a rubber vulcanization accelerator. The anodic oxidation of 2-OHBT on copper, iron and platinum in alcohol and alcohol-water solutions by cyclic polarization and chronoamperometry has been reported.