反应详情

4-(3,4-Dichlorophenyl)-5-(imidazol-1-yl)pent-1-ene hydrochloride (3.6 g) (see Preparation 24) was dissolved in a mixture of acetonitrile (50 ml) and water (20 ml) and osmium tetroxide (4 ml of a 0.05M solution in toluene) added. The mixture was stirred for 30 minutes, sodium periodate (5.3 g) added and stirring continued for 2 hours. A further portion of acetonitrile (20 ml) was added and stirring continued for 16 hours before removal of the organic solvent under reduced pressure to give an aqueous suspension. This was basified to pH>7 by the addition of solid sodium carbonate. The mixture was then extracted with dichloromethane, the organic phase dried over anhydrous sodium sulphate and the solvent removed under reduced pressure to give a dark oil which was chromatographed on silica gel eluting with a solvent gradient of 98:2 changing to 92.5:7.5, by volume, dichloromethane:methanol to give 3-(3,4-dichlorophenyl)-4-(imidazol-1-yl)butan-1-al (2.28 g) as a colourless, viscous oil.

1. additionadded
2. stirringstirring
3. waitcontinued for 2 hours
4. stirringstirring
5. customcontinued for 16 hours before removal of the organic solvent under reduced pressure
6. customto give an aqueous suspension
7. extractionThe mixture was then extracted with dichloromethane
8. dry with materialthe organic phase dried over anhydrous sodium sulphate
9. customthe solvent removed under reduced pressure
10. customto give a dark oil which
11. customwas chromatographed on silica gel eluting with a solvent gradient of 98:2 changing to 92.5:7.5, by volume, dichloromethane