4-methoxy-2,3,5-trimethylbenzenesulfonyl chloride(SALTDATA: FREE) synthesis

Yield:1016500-29-0 40%

Reaction Conditions:

with chlorosulfonic acid in dichloromethane at 0 - 20;

Steps:

A solution of 2-methoxy-1,3,4-trimethylbenzene (85.18 g, 532 mmole) in DCM (500 ml) was cooled to 0° C. A solution of chlorosulfonic acid (38.9 ml, 585 mmole) was added dropwise to the solution and stirred overnight at RT. After completion of the reaction the reaction mixture was concentrated. The residue was taken up in heptane and vigorously stirred. The heptane was decanted and concentrated. Yield: 14.3 g, 11%. The still remaining solids were taken up in DCM. The organic phase was washed with water, dried over Na₂SO₄ and concentrated. A further fraction was obtained in a yield of 38.6 g, 29%.

References:

US2009/186899,2009,A1 Location in patent:Page/Page column 26-27