反应详情

18 ml (0.242 mol) of thionyl chloride are slowly added dropwise to 800 ml of methanol at -10° C., while stirring. A solution of 44.3 g (0.201 mol) of 4-(4-piperidinyl)-butyric acid hydrochloride in 100 ml of methanol is then added dropwise at the same temperature, stirring is continued overnight at room temperature and the mixture is then concentrated to dryness in vacuo. The residue is partitioned between 50% strength potassium carbonate solution and ether. The aqueous phase is extracted twice more with ether. The combined ether extracts are dried and concentrated. The residue is dissolved in methanol and the solution is acidified to pH 6 with ethereal hydrochloric acid and concentrated to dryness in vacuo. The residue which remains is triturated with acetone. The crystals which have separated out are filtered off with suction.

1. stirringstirring
2. concentrationthe mixture is then concentrated to dryness in vacuo
3. customThe residue is partitioned between 50% strength potassium carbonate solution and ether
4. extractionThe aqueous phase is extracted twice more with ether
5. dry with materialThe combined ether extracts are dried
6. concentrationconcentrated
7. dissolutionThe residue is dissolved in methanol
8. concentrationconcentrated to dryness in vacuo
9. customThe residue which remains is triturated with acetone
10. customThe crystals which have separated out
11. filtrationare filtered off with suction