4-Fluorobenzenesulfonyl chloride → Sodium 4-fluorobenzene sulfinate

Participants

Reaction Conditions

Reaction Steps

A solution of 4-fluorobenzenesulfonyl chloride (2 g, 10.28 mmol) in 50 mL of THF (distilled from Na-benzophenone) is cooled to 0+ C. and sodium borohydride (1.9 g, 51.4 mmol) is added portionwise. The reaction is stirred at 0° C. for 2 h, then warmed to RT, and after 2 h, quenched with water (5 mL). The solvent is evaporated and the aqueous residue is acidified by addition of aqueous 6N HCl. The product is taken up in EtOAc, washed with brine, dried over anhydrous Na2SO4 and concentrated to give 4-fluorobenzenesulfinic acid: NMR (DMSO-d6) 7.12 (app t, 2H, J=8.3), 7.5 (dd, 2H, J=8.3, 6); ESI-MS 159 [M−1]−.

Provenance & Evidence