反应详情

A solution of 4.0 g of 6-chloro-3,4-dihydro-2,4-dimethyl-3-oxo-2H-1,4-benzoxazine-8-carboxylic acid in 80 ml of tetrahydrofuran is cooled to below 0° C. and 3.17 g of N-methylmorpholine is added under stirring thereto. Further, 2.35 g of isobutyl chlorocarbonate is added and the mixture is stirred at the same temperature for an hour. To the resultant mixture is added 3.28 g of 3-amino-1-benzylpiperidine and the mixture stirred for 4 hours. After completion of the reaction, aqueous sodium hydrogen carbonate and ethyl acetate are added. The organic layer is separated, washed with water and dried over magnesium sulfate. The solvent is distilled off and the residue is recrystallized from ethanol followed by treating with ethanolic hydrochloric acid to give N-(1-benzyl-4-piperidyl)-6-chloro-3,4-dihydro-2,4-dimethyl- 3-oxo-2H-1,4-benzoxazine-8-carboxamide hydrochloride, melting at 214° C. with decomposition.

1. stirringthe mixture is stirred at the same temperature for an hour
2. stirringthe mixture stirred for 4 hours
3. additionare added
4. customThe organic layer is separated
5. washwashed with water
6. dry with materialdried over magnesium sulfate
7. distillationThe solvent is distilled off
8. customthe residue is recrystallized from ethanol
9. additionby treating with ethanolic hydrochloric acid