Chloride → 4-(p-Fluorophenyl)butyric acid

Participants

Reaction Conditions

Reaction Steps

At 0° C., chlorotrimethylsilane (10.6 ml, 84.1 mmol) was added dropwise to a solution of 4-(4-fluorophenyl)-4-oxobutanoic acid (15.0 g, 76.5 mmol) and triethylamine (11.7 ml, 84.1 mmol) in THF (200 ml). The reaction mixture was stirred for 20 min at 0° C. The solid was filtered off. The solvent was removed from the solution. The residue was dissolved in DCM (200 ml). Triethylsilane (40 ml, 252 mmol) was added. An 1 N solution of titan(IV) chloride in DCM (229 ml, 229 mmol) was added dropwise while cooling with a water bath. The reaction mixture was stirred for 16 hours at room temperature. It was given onto ice water (300 ml). The phases were separated. The aqueous phase was extracted with DCM (100 ml). The combined organic phases were extracted with a saturated aqueous solution of sodium hydrogen carbonate (3×150 ml). The sodium hydrogen carbonate phases were combined and acidified with 1 N hydrochloric acid to pH 2. They were extracted with ethyl acetate (5×150 ml). The combined ethyl acetate layers were dried. The solvent was removed in vacuo to give 7.4 g of crude 4-(4-fluorophenyl)butyric acid, which was used in the next step without further purification.

Provenance & Evidence