Ethyl Acetate → 2-(2-Bromo-4-methylphenyl)-1,3-difluoropropan-2-ol

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of 2-bromo-1-iodo-4-methylbenzene (18.5 g, 62.3 mmol) in THF (25 mL) at 0° C. was slowly added i-PrMgCl (24 mL, 24 mmol). After being stirred for 1 h at 0° C., the reaction mixture was cooled to −78° C. Then a solution of 1,3-difluoropropan-2-one (0.85 g, 9.04 mmol) in dry THF (25 mL) was added. The mixture was stirred at −70° C. for 1 h, and then dry ice bath was removed. The solution was acidified with HCl (2 N) and extracted with EA (60 mL×2). The combined organic layers were washed with brine, dried over Na2SO4, filtered and concentrated under reduced pressure. The residue was purified by column chromatography over silica gel, eluting with PE:EA (5:1) to give 2-(2-bromo-4-methylphenyl)-1,3-difluoropropan-2-ol (1.3 g, yield 55%) as colorless oil. 1H NMR (400 MHz, DMSO-d6): δ 7.60 (d, 1 H), 7.46 (s, 1 H), 7.21 (d, 1 H), 6.21 (s, 1 H), 4.97-4.94 (m, 1 H), 4.85-4.82 (m, 2 H), 4.74-4.71 (m, 1 H), 2.26 (s, 3 H) ppm.

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