Benzenesulfonyl fluoride, 3-chloro-4-fluoro- synthesis

Yield:915763-71-2 95.5%

Reaction Conditions:

with potassium fluoride;18-crown-6 ether in acetonitrile at 20;

Steps:

3a Preparation of reagent R-12a: 3-chloro-4-fluorobenzenesulfonyl fluoride

To a solution of the commercially available 3-chloro-4-fluorobenzenesulfonyl chloride (7 g, 30 mmol) in CH₃CN (40 mL) was added KF (7 g, 120 mmol) and 18-crown-6 (0.5 g), then the mixture was stirred at room temperature overnight. The mixture was quenched with aqueous water and extracted with EtOAc, the organic layer was washed with brine, dried over anhydrous Na₂SO₄, concentrated to give the crude product which was purified by column to give the reagent R-12a (4.2 g, 95.5%) as a pale yellow solid. ESI-MS (M+1 ): 213.2 calc. for C₆H₃CIF₂O₂S

References:

WO2014/12964,2014,A1 Location in patent:Page/Page column 53