反应详情

A mixture comprising 8.24 g of 3-benzyloxybenzylamine hydrochloride prepared in Reference Example 2A, 3.11 g of 2-i-propyl-4,5-dichloro-3(2H)pyridazinone, 7.26 g of potassium carbonate, 30 ml of 1,4-dioxane and 90 ml of water was refluxed under stirring for 4.5 hours. The majority of 1,4-dioxane was distilled off under reduced pressure, and the residue was extracted with ethyl acetate. The extract was washed with diluted hydrochloric acid, and then treated with cerite to remove the precipitate. The organic layer was separated, and washed with water and a saturated sodium chloride aqueous solution, and then dried over sodium sulfate. Then, the solvent was distilled off. The pale yellow oily substance thereby obtained was crystallized from ether-n-hexane to obtain 2.51 g of the above identified compound having a melting point of from 106° to 108° C. as colorless crystals.

1. temperaturewas refluxed
2. distillationThe majority of 1,4-dioxane was distilled off under reduced pressure
3. extractionthe residue was extracted with ethyl acetate
4. washThe extract was washed with diluted hydrochloric acid
5. additiontreated with cerite
6. customto remove the precipitate
7. customThe organic layer was separated
8. washwashed with water
9. dry with materiala saturated sodium chloride aqueous solution, and then dried over sodium sulfate
10. distillationThen, the solvent was distilled off
11. customThe pale yellow oily substance thereby obtained
12. customwas crystallized from ether-n-hexane
13. customto obtain 2.51 g of the
14. customof from 106° to 108° C.