Hydrochloric Acid → 2-Methanesulfonylbenzene-1-sulfonyl chloride

Participants

Reaction Conditions

Reaction Steps

2-Methylsulfonylaniline (6.0 g; 0.035 mole) was added portionwise, with stirring, to a mixture of 30 mL of water and 30 mL of HCl. The mixture was cooled to 5° C. and sodium nitrite (2.7 g; 0.039 mole) dissolved in water (7 mL) was added dropwise maintaining the temperature between 0-5° C. After complete addition of sodium nitrite, the resulting solution was stirred at 0-5° C. for 30 minutes Sulfur dioxide was bubbled into 18 mL of HOAc for 14 min at room temperature. CuCl (0.8 g; 0.008 mole) was added and cooled to 10° C. Sulfur dioxide was bubbled through the suspension for an additional 15 min and the diazotized amine was added portionwise maintaining the temperature between 0-5° C. After the complete addition of diazotized amine, bubbling of SO2 was stopped and the green suspension was stirred at 0-5° C. for 3 hours. At the end of 3 hours, the suspension was diluted with 50 mL of water, filtered and washed three times with 10 mL of water to give, after drying in vacuum (30 in. Hg), 6.4 g (71% yield) of 2-methylsulfonylbenzenesulfonyl chloride which was characterized by its melting point and spectral data. mp 135-137° C. (lit. 133-135° C.). 1H NMR (CDCl3) δ 8.3-8.6 (m, 2H), 7.87-8.02 (m, 2H), 3.41 (s, 3H). 13C NMR (CDCl3) δ 142.94, 139.24, 136.61, 135.22, 133.58, 132.13, 45.49. CIMS (m/e) 255 (M+H+, 100%).

Provenance & Evidence