Imidazole → (R)-Methyl 2-((tert-butoxycarbonyl)amino)-3-((tert-butyldimethylsilyl)oxy)propanoate

Participants

Reaction Steps

To a solution of tert-butyl (R)-1-(methoxycarbonyl)-2-hydroxyethylcarbamate (27.5 g, 0.126 mol) in DMF (250 mL) was added imidazole (25.7 g, 0.378 mol), followed by TBSCl (20.9 g, 0.139 mol) and the reaction mixture was stirred for 4 h. The solvents were removed in vacuo. EtOAc (300 mL) was added and the solution was washed with sat'd aq NH4Cl (2×100 mL), sat'd aq NaHCO3 (100 mL) and brine (100 mL), dried, filtered and evaporated to give tert-butyl (R)-1-(methoxycarbonyl)-2-(t-butyldimethylsilyloxy)ethylcarbamate (40 g, yield 95%) as an oil that was used without further purification. 1H NMR (CDCl3, 400 MHZ): δ=0.02 (s, 6 H), 0.86 (s, 9 H), 1.45 (s, 9 H), 3.73 (s, 3 H), 3.82 (dd, J=14, 4.4 Hz, 1 H), 4.05 (dd, J=13.2, 3.6 Hz, 1H), 4.35 (m, 1 H), 5.34 (brs, 1 H).

Provenance & Evidence