反应详情

1.8 g of methyl 3,4-dihydro-2H-1,4-benzoxazine-6-carboxylate, 93.2 ml of dichloromethane and 4.62 ml of diisopropylethylamine are placed in a 250 ml round-bottomed flask under a nitrogen atmosphere. 1.38 g of triphosgene are added at 0° C. and then the reaction mixture is left stirring at ambient temperature for three hours. 1.62 ml of diisopropylethylamine and 1.45 g of 3-(pyrrolidin-3-yl)pyridine are subsequently added and the reaction mixture is stirred for eighteen hours. A saturated aqueous sodium hydrogencarbonate solution and dichloromethane are added. The aqueous phase is extracted three times with dichloromethane. The organic phases are combined, washed with water and with a saturated aqueous sodium chloride solution and dried over sodium sulfate and then the solvent is evaporated under reduced pressure. The residue is chroratographed on silica gel with a dichloromethane/methanol 95/5 mixture. 2.39 g of methyl 4-[(3-(pyridin-3-yl)pyrrolidin-1-yl)carbonyl]-3,4-dihydro-2H-1,4-benzoxazine-6-carboxylate are obtained.

1. waitthe reaction mixture is left
2. stirringthe reaction mixture is stirred for eighteen hours
3. extractionThe aqueous phase is extracted three times with dichloromethane
4. washwashed with water and with a saturated aqueous sodium chloride solution
5. dry with materialdried over sodium sulfate
6. customthe solvent is evaporated under reduced pressure