反应详情

A mixture of 20 g of 2-benzoyl-cyclohexanone, 21.6 g of ethyl pyruvate and 0.2 g of p-toluenesulfonic acid is heated at 150° for 15 hours. There is removed that fraction which distills at 1 mm (Hg up to 150°) and the residue is heated for 10 hours at 230° with 5 parts by weight of pyridine hydrochloride. After cooling the raw reaction products are poured in water and extracted with ether. The residue which is obtained after evaporation of the solvent is steam distilled. The part which does not distil is extracted with ether, the ether solution is dried well over sodium sulfate and to the dried solution there is added diethylamine until a clearly alkaline pH is reached. There thus precipitates a mixture of diethylamine salts from which, through fractional crystallization with hexane-ethyl acetate there is obtained the diathylamine salt of m-benzoyl-hydratropic acid m.p. 102°-104°. The free acid is obtained therefrom with the usual techniques.

1. temperatureis heated at 150° for 15 hours
2. customThere is removed that fraction which
3. distillationdistills at 1 mm (Hg up to 150°) and the residue
4. temperatureis heated for 10 hours at 230° with 5 parts by weight of pyridine hydrochloride
5. temperatureAfter cooling the raw
6. customreaction products
7. extractionextracted with ether
8. customThe residue which is obtained
9. customafter evaporation of the solvent
10. distillationdistilled
11. customThe part which does not distil
12. extractionis extracted with ether
13. dry with materialthe ether solution is dried well over sodium sulfate and to the dried solution there
14. additionis added diethylamine until a clearly alkaline pH
15. customThere thus precipitates
16. additiona mixture of diethylamine salts from which
17. customthrough fractional crystallization with hexane-ethyl acetate there