Hydrochloric Acid → (Boc)2NN(Boc)CH2CONHCH2CH2N3

Participants

Reaction Steps

HCl.H2NCH2CH2N3 (4) was synthesized by dissolving azide 3 (2.11 g, 11.33 mmol) in 4 N HCl in dioxane (100 mL) and stirring at room temperature for 1 h. The solvent was removed under reduced pressure to give a dirty white powder. (Boc)2NN(Boc)CH2CO2H (4.42 g, 11.33 mmol) was then added, and the mixture was dissolved in methylene chloride/DMF (70:45 mL). The mixture was cooled to 0° C., and PyBOP (5.9 g, 11.33 mmol) and Et3N (3.2 mL, 22.66 mmol) were added. The reaction mixture was allowed to warm to room temperature and stirred under Ar(g) for 21 h. The solvent was removed under reduced pressure, and the residue was purified by flash chromatography (silica gel, 50% v/v ethyl acetate in hexanes) to give (Boc)2NN(Boc)CH2CONHCH2CH2N3 as a colorless viscous oil (4.9 g, 95%). HRMS (ESI) [M+Na]+ calcd for C19H34N6O7Na, 481.2387; found, 481.2389; 1H NMR (400 MHz, CDCl3, 2 rotamers) δ 8.51 and 8.27 (bs, 1H), 4.06 and 3.99 (s, 2H), 3.49-3.40 (m, 4H), 1.56-1.44 (m, 27H); 13C NMR (100 MHz, CDCl3, 2 rotamers) δ 169.5, 169.2, 154.0, 153.5, 151.4, 151.2, 85.2, 85.1, 83.5, 82.8, 56.5, 54.8, 50.6, 38.9, 34.1, 29.9, 28.2, 28.1.

Provenance & Evidence