反应详情

A mixture of ethyl 2-ethyl-3-[2'-(1-trityl-1H-tetrazol-5-yl)biphenyl-4-yl]methyl-4,5,6,7-tetrahydroimidazo[4,5-c]pyridine-4-carboxylate (1.51 g), acetic anhydride (0.44 g), sodium hydrogen carbonate (1.09 g), chloroform (18 ml) and water (18 ml) is stirred overnight at room temperature. The aqueous layer is extracted with chloroform, and the combined organic layer is washed with aqueous citric acid solution and brine, dried, and evaporated. To the residue (1.46 g) is added fumaric acid (1.2 g) and ethanol (20 ml), and the mixture is refluxed for four hours, then evaporated. The residue is treated with a saturated sodium hydrogen carbonate solution and then extracted with chloroform. The organic layer is dried and evaporated. Purification by silica gel column chromatography (solvent; chloroform/methanol) gives ethyl 2-ethyl-5-acetyl-3-[2'-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl-4,5,6,7-tetrahydroimidazo[4,5-c]pyridine-4-carboxylate (0.76 g) as a white foam.

1. extractionThe aqueous layer is extracted with chloroform
2. washthe combined organic layer is washed with aqueous citric acid solution and brine
3. customdried
4. customevaporated
5. additionTo the residue (1.46 g) is added fumaric acid (1.2 g) and ethanol (20 ml)
6. temperaturethe mixture is refluxed for four hours
7. customevaporated
8. additionThe residue is treated with a saturated sodium hydrogen carbonate solution
9. extractionextracted with chloroform
10. customThe organic layer is dried
11. customevaporated
12. customPurification by silica gel column chromatography (solvent; chloroform/methanol)