反应详情

A mixture comprising 500 mg of 4-chloro-5-(3-n-propoxy-4-methoxybenzylamino)-6-nitro-3(2H)pyridazinone (Compound No. 22) prepared in Example 2, 634 mg of ethyl iodide, 562 mg of anhydrous potassium carbonate and 25 ml of methyl ethyl ketone, was refluxed under stirring for 1.5 hours. The solvent was distilled off under reduced pressure, and water was added to the residue thereby obtained and the mixture was extracted with diethyl ether. The extract was washed with a saturated sodium chloride aqueous solution and dried over sodium sulfate. Then, the solvent was distilled off, and the residual oily substance thereby obtained was crystallized from a solvent mixture of diethyl ether-n-hexane, to obtain 473 mg of the above identified compound having a melting point of from 76° to 77° C. as yellow crystals.

1. temperaturewas refluxed
2. distillationThe solvent was distilled off under reduced pressure, and water
3. additionwas added to the residue
4. customthereby obtained
5. extractionthe mixture was extracted with diethyl ether
6. washThe extract was washed with a saturated sodium chloride aqueous solution
7. dry with materialdried over sodium sulfate
8. distillationThen, the solvent was distilled off
9. customthe residual oily substance thereby obtained
10. customwas crystallized from a solvent mixture of diethyl ether-n-hexane
11. customto obtain 473 mg of the
12. customof from 76° to 77° C.