反应详情

2.35 g of 3-methyl 5-(2-bromoethyl) (+)-1,4-dihydro-2,6-dimethyl-4-(3-nitrophenyl)-pyridine-3,5-dicarboxylate, 1.46 g of 4,4-diphenylpiperidine hydrochloride and 1.55 g of finely powdered potassium carbonate in 15 ml of anhydrous dimethylformamide are stirred for 6 h at 80° C. After the mixture has cooled, 100 ml of water are added and the mixture is then extracted with ether. The ether phase is washed twice with water, dried over sodium sulphate and then evaporated in vacuo. The residue is chromatographed over a silica gel column using a 95:5 chloroform/ethanol as the mobile phase. The chromatographically pure fractions are collected and evaporated. The residue is dissolved in ether and 2 ml of a saturated solution of hydrogen chloride in ether are added to the solution, crystallisation occurring. The product is filtered off under suction, washed with ether and dried. 1.4 g of the title compound of m.p. 155°-158° C. (decomp.) and [α]22D =+68.4° (c=1, methanol) are obtained.

1. temperatureAfter the mixture has cooled
2. extractionthe mixture is then extracted with ether
3. washThe ether phase is washed twice with water
4. dry with materialdried over sodium sulphate
5. customevaporated in vacuo
6. customThe residue is chromatographed over a silica gel column
7. customThe chromatographically pure fractions are collected
8. customevaporated
9. dissolutionThe residue is dissolved in ether
10. addition2 ml of a saturated solution of hydrogen chloride in ether are added to the solution, crystallisation
11. filtrationThe product is filtered off under suction
12. washwashed with ether
13. customdried