4-Methylmorpholine → Benzyl 1-(2,2-dimethoxyethylamino)-2-methyl-1-oxopropan-2-ylcarbamate

Participants

Reaction Steps

A mixture of 2-(benzyloxycarbonylamino)-2-methylpropanoic acid (20 g, 0.084 mol), HATU (CAN 148893-10-1, 41.56 g, 0.11 mol) and N-methylmorpholine (CAN 109-02-4, 25.54 g, 0.253 mol) in DMF (400 mL) was stirred at room temperature for 10 min. 2,2-Dimethoxyethanamine (CAN 22483-09-6, 9.75 g, 0.093 mol) was added and the mixture was stirred overnight. After evaporation of solvents, the residue was diluted with methylene chloride (500 mL) and saturated sodium bicarbonate solution (500 mL). After being separated, the organic layer was washed with 5 N citric acid solution (500 mL), brine (500 mL) and dried over anhydrous sodium sulfate. Removal of the solvent under reduced pressure left a yellow oil (27 g, 99%) which was used in the next reaction step without further purification. 1H NMR (300 MHz, CDCl3): δ 7.36-7.33 (m, 5H), 6.44-6.38 (b, 1H), 5.31 (s, 1H), 5.09 (s, 2H), 4.34-4.33 (m, 1H), 3.40-3.37 (m, 8H), 2.06-2.03 (m, 6H).

Provenance & Evidence