2-(4-Fluorophenyl)acetic acid → 4-Fluorophenylacetyl chloride

Participants

Reaction Steps

To a solution of 4-fluorophenylacetic acid (1) (25 g, 162 mmol) in DCM (75 mL) was added oxalyl chloride (28.4 mL. 324 mmol) and 3-4 drops of DMF. The mixture was stirred at r.t. for 1 h-2 h and concentrated to produce 2-(4-fluorophenyl)acetyl chloride (1a) (yellow oil) that was re-dissolved in toluene (100 mL). To this solution was added lead(II) thiocyanate (55.0 g, 170 mmol). The mixture was heated to reflux for 1.5 h-2 h, cooled down, filtered and the filtrate was concentrated. The residue was applied onto a silica gel pad (20 cm) and eluted with EtOAc/hexanes (1/9), to afford after evaporation of the solvents title compound 2 (31 g, 98% yield) as a yellow oil. MS (m/z): 228.1 (M+H+MeOH). 1H NMR (400 MHz, DMSO-d6) δ (ppm): 7.26-7.22 (m, 2H), 7.09-7.07 (m, 2H), 3.84 (s, 2H).

Provenance & Evidence