Hydrochloric Acid → HCID 20355557, compound

Participants

Reaction Steps

Sulfonamide 6 (109 g, 0.26 mol) was dissolved in DMF (800 mL) and stirred at ambient temperature. To this was added K2CO3 (63 g, 0.46 mol) in one portion and the resultant mixture heated at reflux (oil bath 160° C.) for 3 hours. After this time the heating was ceased and the reaction allowed to cool with stirring overnight. The completed reaction was poured into water (1 L) and acidified with aqueous HCl (1 M, ˜500 mL) to pH 2. The resultant brown suspension was extracted with DCM (5×500 mL) and the combined organics washed with brine (1 L). A thick emulsion formed which was separated by the addition of iPrOAc until two distinct layers were visible. The organics were separated, dried (MgSO4) and evaporated to give an orange oil (66 g). This oil was purified by flash column chromatography (silica gel, 5% MeOH/DCM) to yield dioxide 7 as a yellow-orange oil (40 g, 64%).

Provenance & Evidence