Diisopropylethylamine → benzyl N-(2-oxoethyl)carbamate

Participants

Reaction Steps

To a stirred solution of (2-hydroxyethyl)carbamic acid benzyl ester (1.0 g, 5.1 mmol) and DIPEA (1.78 mL, 10.2 mmol) in DCM (15 mL) was added a solution of sulfur trioxide-pyridine complex (1.63 g, 10.2 mmol) in DMSO (15 mL) at −20° C. After 1 h, the reaction was warmed to room temperature, diluted with dichloromethane (50 mL) and washed with 1.0 N HCl (50 mL) and brine. The organics were separated, dried with anhydrous sodium sulfate, filtered, concentrated, and purified by silica gel chromatography to give the title intermediate (810 mg, 82%). 1H NMR (CDCl3, 300 MHz) δ (ppm): 9.5 (s, 1H) 7.4-7.2 (m, 5H), 5.1 (s, 2H), 3.9 (d, J=5.8 Hz, 2H), 2.9-3.3 (br, 1H).

Provenance & Evidence