Dimethylacetamide → 8-Benzyloxy-1,3,3-trimethyl-1,5-dihydrobenzo[b][1,4]diazepine-2,4-dione

Participants

Reaction Steps

Under ice cooling, dimethylmalonic acid dichloride (9.9 mL, 74.9 mmol) was added dropwise to a N,N-dimethyl acetamide (90 mL) solution of 5-benzyloxy-N1-methylbenzene-1,2-diamine hydrochloride (18.0 g, 68.0 mmol). The mixture was stirred at the same temperature for 2.5 hours, and water (90 mL) was added thereto. The reaction solution was stirred at 10° C. or less for 30 minutes, and precipitated crystals were collected by filtration. The resulting crystals were washed with water, then added to methanol (180 mL), and heated under reflux. The mixture was cooled and stirred at 10° C. or less for 30 minutes, and precipitated crystals were collected by filtration. The resulting crystals were washed with methanol (36 mL), and dried at 60° C., thereby obtaining 18.3 g of a white, powdery target compound (yield: 83%).

Provenance & Evidence