Hydrochloric Acid → HCID 14392098, compound

Participants

Reaction Steps

A solution of 5,6-dihydro-4-ethylamino-6,6-dimethyl-4H thieno[2,3-b]thiopyran-2-sulfonamide (3.95 g, 0.013 mol) in methanol (85 ml) was acidified with 6.25N methanolic hydrogen chloride (2.1 ml). With stirring, a solution of `OXONE` (11.68 g, 0.019 mol) in water (65 ml) was added over 15 minutes. After stirring at ambient temperature for 17.5 hours, the mixture was filtered and the solid was washed with methanol. The combined filtrate and washings were concentrated in vacuo below 55° C. to remove methanol and the cloudy aqueous solution was basified with saturated sodium bicarbonate solution. The mixture was extracted with ethyl acetate (150 ml and 2×100 ml), and the combined extracts were washed twice with water, dried over sodium sulfate and evaporated in vacuo. The amorphous residue was converted to the crystalline hydrochloride salt using ethanolic hydrogen chloride to yield 2.16 g (44%) of analytically pure product melting at 255°-255.5° C.

Provenance & Evidence