Borane;tetrahydrofuran → HCID 66724839, compound

Participants

Reaction Conditions

Reaction Steps

Two-hundred (200) mg (0.48 mmol) of Boc-(3R)-4-amino-3-[4-chloro-3-(3-cyanophenyl)phenyl]butanoic acid (52a) (200 mg, 0.48 mmol) was dissolved in 1 mL of tetrahydrofuran (THF). The reaction mixture was cooled to 0° C. and 3 equivalents of 2M borane/THF solution was added. The mixture was warmed to room temperature and stirred for 3 days. The reaction mixture was then carefully quenched with excess methanol. After stirring for 15 min, 2 mL of 1N NaOH was added and the mixture stirred for one hour. The mixture was extracted with ethyl acetate (3×10 mL), the aqueous solution acidified to pH 3, and then extracted two additional times with ethyl acetate. The combined organic layers were dried over Na2SO4 and concentrated in vacuo. The crude residue was purified by HPLC to provide the title compound (53) (4.3 mg, 10% yield). 1H-NMR (400 MHz, CD3OD): δ 1.93-2.01 (m, 1H), 1.81-1.88 (m, 1H), 3.22-3.27 (dd, J=22.4, 9.6 Hz, 1H), 3.14-3.19 (m, 1H), 3.30-3.39 (m, 1H), 3.52-3.57 (m, 1H), 7.54-7.56 (m, 1H), 7.33-7.36 (m, 2H), 7.61-7.65 (m, 1H), 7.75-7.78 (m, 1H), 7.80-7.81 (m, 1H); MS (ESI) m/z 301.04 (M+H)+.

Provenance & Evidence