Triethylamine → Benzyl tert-butyl malonate

Participants

Reaction Steps

Carbamoylmethyl-carbamic acid tert-butyl ester (8a; 0.84 g, 4.8 mmol) was dissolved in dichloromethane (10 mL), and added with triethylamine (1.0 mL, 7.2 mmol) and benzyl chloroformate (0.85 g, 0.75 mL, 5.0 mmol) at 0° C. After stirring for 5 min, 4-dimethylaminopyridine (DMAP; 0.32 g, 2.6 mmol) was added slowly with continuous stirring at 0° C. for 1 h. After the reaction is completed, dichloromethane (10 mL) and saturated Na2CO3 solution (10 mL) were added. The organic phase was washed by H2O (10 mL), 1N HCl (20 mL), H2O (20 mL) and saturated NaCl solution (20 mL) separately, and dried over MgSO4 and concentrated under reduced pressure to remove dichloromethane to obtain white solid product 12 (1.15 g; 95%). 1H-NMR (200 MHz) (CDCl3) δ: 7.30˜7.38 (m, 5H, ArH), 5.17 (s, 2H, CO2CH2Ph), 5.02 (br, s, 1H, NHBOC), 3.94 (d, 2H, Gly-H), 1.43 [s, 9H, CO2C(CH3)3]

Provenance & Evidence