2-Trifluoromethylbenzylsulfonyl chloride synthesis

Yield: 85%

Reaction Conditions:

with oxalyl dichloride;N,N-dimethyl-formamide in tetrahydrofuran at -20 - 0; for 5 h;

Steps:

5.3
To a suspension of (2-trifluoromethylphenyl)methanesulfonic acid (20.3 g, 84 mmol) in THF (1.9 L) and DMF (5.0 mL) at -20 ⁰C was added oxalyl chloride (44.7 mL,0.5 mol) slowly dropwise over 1hr. The bath temperature was maintained below 0 ⁰C for4 h, at which point the reaction was evaporated to a volume of ~ 250 mL and diluted with 50OmL of ethyl acetate. This solution was washed with brine in a separatory funnel and dried over magnesium sulfate. The solution was then evaporated to a brown oil. This oil was taken up in 50OmL of pet ether (30-50°) and heated with a heat gun until the oil went into solution. The solution was then placed into a dry-ice acetone bath to cool resulting in formation of a white crystalline material. This material was collected via EPO filtration and dried to afford 19 g (85%) of (2-trifluoromethylphenyl)methanesulfonyl chloride as a white solid.

References:

WYETH WO2006/128142, 2006, A2 Location in patent:Page/Page column 31-32