Iodine → (4-Bromo-3-fluorophenyl)methanol

Participants

Reaction Steps

A suspension of 4-bromo-3-fluorobenzoic acid (84) (1.61 g, 7.35 mmol) in anhydrous THF (10 mL, then 4×3 mL to rinse) under N2 was added drop-wise (over 40 min) to a suspension of sodium borohydride (400 mg, 10.6 mmol) in anhydrous THF (15 mL) under N2, and then the mixture was cooled in an ice bath. A solution of iodine (1.008 g, 3.97 mmol) in anhydrous THF (10 mL, then 2×3 mL) was added drop-wise (over 35 min) to the stirred solution and then the mixture was stirred at room temperature for 14 h. The mixture was concentrated under reduced pressure and then treated successively with water (20 mL), 10% HCl (3.4 mL) and water (20 mL), and extracted with CH2Cl2 (4×50 mL). The extracts were evaporated to dryness and the residue was chromatographed on silica gel, eluting with 50% CH2Cl2/petroleum ether, to give (4-bromo-3-fluorophenyl)methanol (85) (1.096 g, 73%) as a white solid: mp (CH2Cl2/petroleum ether) 39-40° C.; 1H NMR (CDCl3) δ 7.52 (dd, J=8.0, 7.2 Hz, 1H), 7.16 (dd, J=9.3, 1.8 Hz, 1H), 7.02 (dd, J=8.2, 1.8 Hz, 1H), 4.67 (d, J=5.9 Hz, 2H), 1.75 (t, J=5.9 Hz, 1H); HREIMS calcd for C7H6BrFO m/z (M+) 205.9567, 203.9586, found 205.9566, 203.9580.

Provenance & Evidence