反应详情

A mixture of 3.0 g of ethyl 4-chloro-7-methyl-1,8-naphthyridine-3-carboxylate (prepared according to U.S. Pat. No. 3,786,043) and 1.42 g of phenylhydrazine in 30 ml of n-butanol is refluxed for 18 hours. The mixture is chilled in an ice bath and filtered to give a solid which is taken up in 50 ml of 1N sodium hydroxide and sufficient water to dissolve. The resulting solution is filtered to remove insoluble, washed with ether and neutralized with 3.0 g of ammonium chloride. The resulting mixture is filtered collecting a solid which is washed with water and dried to yield 7-methyl-2-phenylpyrazolo[4,3-c][1,8]naphthyridin-3(5H)-one hemihydrate, m.p. 305°-308°.

1. customprepared
2. temperatureThe mixture is chilled in an ice bath
3. filtrationfiltered
4. customto give a solid which
5. filtrationThe resulting solution is filtered
6. customto remove insoluble
7. washwashed with ether and neutralized with 3.0 g of ammonium chloride
8. filtrationThe resulting mixture is filtered
9. customcollecting a solid which
10. washis washed with water
11. customdried