4-Methylmorpholine → Benthiavalicarb isopropyl

Participants

Reaction Conditions

Reaction Steps

In 500 ml of toluene, 18.9 g (0.093 mol) of N-isopropoxycarbonyl-L-valine was dissolved. The solution was cooled to −5° C. Thereto were dropwise added, at −5° C., 23.0 g (0.233 mol) of N-methylmorpholine and 12.7 g (0.093 mol) of isobutyl chlorocarbonate. Thereto was added, at −5° C., 17.4 g (0.047 mol) of (R)-1-(6-fluoro-2-benzothiazolyl)ethylamine p-toluenesulfonate in one portion. The mixture was stirred at the same temperature for 0.5 hour and then at room temperature for 2 hours. To the reaction mixture was added 300 ml of water. The mixture was heated to 70° C. to dissolve the solid. The toluene layer was separated, washed with hot water, and then cooled, whereby a solid was precipitated. The solid was collected by filtration and dried to obtain 23.7 g (yield: 70%) of isopropyl {(S)-1-[(R)-1-(6-fluorobenzothiazol-2-yl)ethylcarbamoyl]-2-methylpropyl}carbamate. The compound obtained was confirmed for the structure by IR analysis and NMR analysis in comparison with its authentic material and identified.

Provenance & Evidence