Hydroquinone → Potassium dobesilate

Participants

Reaction Conditions

Reaction Steps

Hydroquinone (20 g, 0.1816 mol) and n-heptane (60 mL) was taken in a round bottom flask, after cooling the flask to about 10-15° C., sulfuric acid (36 N, 17.8 g) was added dropwise at the same temperature and stirring continued further for about 10-15 min. The temperature was slowly raised to 50-60° C. then stirred for 3-8 h. The reaction mass was then cooled to 25-35° C., n-heptane was decanted and ethyl acetate (200 mL) added to dissolve the solid formed. A solution of potassium 2-ethylhexanoate (36.4 g, 0.1996 mol) in ethyl acetate (200 mL) was added slowly. The reaction was further stirred for an hour. The precipitated crude solid was filtered, washed with ethyl acetate to give 40 g of 2,5-dihydroxybenzenesulfonic acid potassium salt.

Provenance & Evidence