Hydrogen iodide → 3-(5-hydroxy-2-methyl-1,3-benzothiazol-6-yl)-1,3-dihydro-2H-indol-2-one

Participants

Reaction Steps

A mixture of 3-hydroxy-3-(5-hydroxy-2-methyl-1,3-benzothiazol-6-yl)-1,3-dihydro-2H-indol-2-one (4.81 g, 15.4 mmol) and 48% aqueous hydroiodic acid (25 mL) was heated at reflux for 1 h. The reaction mixture was allowed to cool to ambient temperature and was diluted with water (50 mL) and ethyl acetate (50 mL). The mixture was briefly sonicated, causing a precipitate to be deposited. The solid was collected by filtration, washed with water (20 mL) and dried in vacuo to afford 3-(5-hydroxy-2-methyl-1,3-benzothiazol-6-yl)-1,3-dihydro-2H-indol-2-one (4.52 g, 99%) as a pale yellow solid: MS (ES+) m/z 297.2 (M+1).

Provenance & Evidence