Diisopropylethylamine → N2-(tert-butoxycarbonyl)-N,N2-dimethyl-N-[3-(triphenylphosphonio)propyl]glycinamide bromide

Participants

Reaction Steps

N-(tert-butoxycarbonyl)-N-methylglycine (309 mg, 1.63 mmol) was taken up in methylene chloride (7.8 mL) and treated with N,N-diisopropylethylamine (1.0 mL, 5.7 mmol), and 1-hydroxybenzotriazole hydrate (233 mg, 1.52 mmol). After 10 minutes at room temperature, [3-(methylamino)propyl](triphenyl)phosphonium bromide hydrobromide (933 mg, 1.88 mmol) was added, followed by 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (353 mg, 1.84 mmol) and 4-dimethylaminopyridine (145 mg, 0.11 mmol). The mixture was stirred overnight at room temperature. The reaction was isolated by washing with aqueous NaHCO3 and water to give crude product that was purified on a silica gel column eluting with 5-10% 1 M NH3 in methanol and methylene chloride to give the title compound (739 mg) in a 76% yield.

Provenance & Evidence