反应详情

A mixture of 6-bromo-8-methyl-2-(1H)-quinolone (2.38 g), (see Preparation 67 of European patent application publication No. 0148623), 4-acetyl-2-methylimidazole (2.48 g), finely divided copper-bronze (0.64 g), potassium carbonate (1.38 g), and a few crystals of iodine was stirred and heated in N-methyl-2-pyrrolidone (8 cm3) at 190° C. for 24 hours under nitrogen. The cooled mixture was then poured into methanol:dichloromethane (100 cm3, 1:10 by volume), stirred and filtered. The filtrate was poured into aqueous ammonia (20 cm3, S.G. 0.880) and the mixture was filtered through "Solkafloc" (Trademark for a cellulose-based filtering aid). The filtrate was separated and the aqueous phase was re-extracted with methanol:dichloromethane (3×100 cm3), 1:10 by volume). The combined and dried (MgSO4) organic extracts were evaporated in vacuo to give a residue which was chromatographed on silica (Merck "MK 60.9385" [Trademark]). Elution with methanol:dichloromethane, 1:33 by volume, followed by combination and evaporation of the appropriate fractions, gave unreacted starting bromo-quinolone (0.68 g) and a solid which was recrystallised from ethyl acetate/methanol to afford the title compound, m.p. 306°-8°, (0.26 g), which was also confirmed spectroscopically to be identical to the product of Example 3.

1. customPreparation 67 of European patent application publication No
2. filtrationfiltered
3. additionThe filtrate was poured into aqueous ammonia (20 cm3, S.G. 0.880)
4. filtrationthe mixture was filtered through "Solkafloc" (Trademark for a cellulose-
5. filtrationbased filtering aid)
6. customThe filtrate was separated
7. extractionthe aqueous phase was re-extracted with methanol
8. dry with materialdried (MgSO4) organic extracts
9. customwere evaporated in vacuo
10. customto give a residue which
11. customwas chromatographed on silica (Merck "MK 60.9385" [Trademark])
12. washElution with methanol
13. customdichloromethane, 1:33 by volume, followed by combination and evaporation of the appropriate fractions
14. customgave unreacted
15. customa solid which was recrystallised from ethyl acetate/methanol