反应详情

(5)In 25 ml of dry N,N-dimethylformamide was dissolved 11.0 g (25.1 mmol)of 5-(3,5-dichlorophenylthio)-4-isopropyl-2-(p-methoxybenzyloxymethyl)-1H-imidazole (16b), followed by addition of 5.2 g (38 mmol)of potassium carbonate powder. Then, 3.90 g (27.7 mmol)of methyl iodide was further added and the mixture was stirred at room temperature for 8 hours. This reaction mixture was concentrated under reduced pressure and the residue was diluted with water and extracted with diethyl ether. The organic layer was washed with water and dried over magnesium sulfate. The solvent was distilled off under reduced pressure and the residue was fractionated by silica gel chromatography (ethyl acetate:methylene chloride=1:9). From the first fraction, 1.7 g (yield 15%)of the objective position isomer (17b')was obtained as oil. From the subsequent fraction, 9.14 g (yield 80%)of the objective 5-(3,5-dichlorophenylthio)-1-methyl-4-isopropyl-2-(p-methoxybenzyloxymethyl)-1H-imidazole (17b)was obtained. mp 79-80° C.

1. concentrationThis reaction mixture was concentrated under reduced pressure
2. additionthe residue was diluted with water
3. extractionextracted with diethyl ether
4. washThe organic layer was washed with water
5. dry with materialdried over magnesium sulfate
6. distillationThe solvent was distilled off under reduced pressure
7. customFrom the first fraction, 1.7 g (yield 15%)of the objective position isomer (17b')was obtained as oil