反应详情

Diisopropylamine (0.563 g) was covered with 5 ml of tetrahydrofuran and 2 ml of 2.5M n-butyl lithium in hexane was added at -78° C. The mixture was stirred for 15 minutes, was then methyl 3-(2-thienyl)propenoate (0.89 g) in 3 ml of tetrahydrofuran was added. After 20 minutes, 1.04 g of 1-[2-(1-adamantyl)ethyl]-2-n-butyl-imidazol-5-carbox-aldehyde in 3 ml of tetrahydrofuran was added and the mixture was stirred for 30 minutes at -78° C. The mixture was poured into 40 ml of saturated ammonium chloride in water, extracted with ether, dried over magnesium sulfate, filtered, concentrated and chromatographed on silica gel eluting with 70% ethyl acetate and 30% hexane to give methyl 3-[1-(2-(1-adamantyl)ethyl)-2-n-butyl-1H -imidazol-5-yl]-3-hydroxy-2-(2-thienylmethyl)propanoate. To 1.27 g of this compound in methylene chloride (25 ml) was added 4-dimethylaminopyridine (1.25 g), then acetic anhydride (2.75 g) was added dropwise. The mixture was stirred for one hour, then poured into water and worked up to give 3-acetoxy-3-[1-(2-(1-adamantyl)ethyl)-2-n-butyl-1H -imidazol-5-yl]-2-(2-thienylmethyl)propanoate.

1. additionwas added at -78° C
2. waitAfter 20 minutes
3. stirringthe mixture was stirred for 30 minutes at -78° C
4. extractionextracted with ether
5. dry with materialdried over magnesium sulfate
6. filtrationfiltered
7. concentrationconcentrated
8. customchromatographed on silica gel eluting with 70% ethyl acetate and 30% hexane