反应详情

19 g (38 mmols) of (+)-1,4-dihydro-2,6-dimethyl-4-(3'-nitrophenyl)-pyridine-3,5-carboxylic acid isopropyl 2-methoxy-2-phenylethyl ester (compound A) in a solution of 0.87 g (38 mmols) of sodium in 100 ml of ethanol are heated to the boiling point under nitrogen for 8 hours. The solvent is then distilled off in vacuo, the residue is taken up in water and the mixture is acidified with dilute hydrochloric acid and extracted several times with methylene chloride. The extracts are concentrated in vacuo, after drying over sodium sulphate. The residue crystallised completely and is filtered off and recrystallised from methanol (crude yield: 4.1 g (2,%), melting point: 143°-146° C.), and the product is purified by high performance liquid chromatography, as described under

1. distillationThe solvent is then distilled off in vacuo
2. extractionextracted several times with methylene chloride
3. concentrationThe extracts are concentrated in vacuo
4. dry with materialafter drying over sodium sulphate
5. customThe residue crystallised completely
6. filtrationis filtered off
7. customrecrystallised from methanol (crude yield: 4.1 g (2,%), melting point: 143°-146° C.)
8. customthe product is purified by high performance liquid chromatography