Benzyl Bromide → HCID 68669637, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of methyl 2-(4-butyl-2,3-dioxopiperazin-1-yl)acetate (Intermediate E, 270 mg, 1.1 mmol) in 10 mL THF, cooled to −78° C., was added lithium bis(trimethylsilyl)amide (1M solution in THF, 1.3 mL, 1.3 mmol) dropwise. The reaction was stirred at −78° C. for 30 min and benzyl bromide (0.33 mL, 2.75 mmol) was added. The mixture was allowed to warm to rt over 2.5 h, quenched with saturated NH4Cl solution and extracted with EtOAc. The combined organic layers were washed with brine, dried and concentrated. Flash chromatography (silica gel, 50-100% EtOAc/hexanes) gave methyl 2-(4-butyl-2,3-dioxopiperazin-1-yl)-3-phenylpropanoate. 1H NMR (CDCl3) δ 7.26 (m, 5H), 5.35 (X of ABX, 1H, J=11 Hz, J=5.6 Hz), 3.76 (s, 3H), 3.47-3.34 (m, 6H), 3.12 (m, 2H), 1.49 (m, 2H), 1.27 (m, 2H), 0.90 (t, 3H, J=7.3 Hz).

Provenance & Evidence