Allyl bromide → 2-Allyl-3-(3-fluoro-phenyl)-pentanedioic acid 1-methyl ester

Participants

Reaction Steps

To a cooled (-78° C.) solution of LDA (7.1 mL, 2.0 M, 14.2 mmol) in 50 mL THF was added a solution of 3-(3-fluoro-phenyl)-pentanedioic acid monomethyl ester (2-4) (1.58 g, 6.58 mmol) in 10 mL THF gradually. The mixture was stirred for 40 min, treated with allyl bromide (1.71 mL, 19.7 mmol) at -78° C. and stirred overnight while it was warmed to room temperature. It was then concentrated and diluted with 20 mL CH2Cl2 and 15 mL EtOH. To the resulting solution was added EDAC (1.88 g, 9.87 mmol) and DMAP (25 mg, 0.02 mmol). After stirring for 5 hr, the reaction was quenched with 20 mL 10% NaHCO3 and extracted with EtOAc (×3). The combined organic layers were washed with brine, dried (Na2SO4) and concentrated to provide 2-5 as an oil, which was further purified using flash silica chromatography (Hexane/EtOAc, 4:1).

Provenance & Evidence