Dimethyl Sulfoxide → Di-tert-butyl (2-oxopropane-1,3-diyl)dicarbamate

Participants

Reaction Conditions

Reaction Steps

To a solution of dimethyl sulfoxide (25.2 ml, 0.36 mol) in methylene chloride (357 ml) at −78° C. (dry ice/acetone) was added a solution of oxalyl chloride (20 ml, 0.23 mol) in methylene chloride (115 ml). The reaction mixture was stirred at −78° C. for 30 min under an atmosphere of N2 then a solution of (3-tert-Butoxycarbonylamino-2-hydroxy-propyl)-carbamic acid tert-butyl ester (31.9 g, 0.11 mol) in methylene chloride (300 ml) and triethylamine (75 ml, 0.54 mol) were added. The reaction was stirred for 16 hours, allowing the reaction to warm up to room temperature. The mixture was diluted with water (800 ml) and extracted with methylene chloride (2×300 ml). The combined organic extracts were dried (Na2SO4), filtered, and concentrated in vacuo to afford a yellowish oil. Purification via column chromatography on silica gel (ethyl acetate:hexane, 3:7, v/v) afforded the product as a white solid (28 g, 88%). 1H NMR (CDCl3) δ 1.44 (s, 18H), 4.04 (m, 4H), 5.19 (s, 1H).

Provenance & Evidence