反应详情

A commercial solution of 25 wt % sodium methoxide in methanol (0.49 mL, 2.0 mmol) was added drop wise to an ice-cooled solution of 4-phenyl-3,6-dichloropyridazine (1-1; 448 mg, 2.0 mmol) in dry methanol (10 mL). This solution was gradually warmed to room temperature over three hours. The solvent was evaporated and the residue dissolved in methylene chloride, washed with aq. NaHCO4, the organic layer dried over anhydrous Na2SO4, filtered and evaporated to give a 2:1 mixture of isomeric products. Upon chromatography on silica gel and elution with 15% ethyl acetate/hexane, the desired and major isomer was isolated. Trituration of this material with diethyl ether/hexane afforded 3-chloro-6-methoxy-4-phenylpyridazine as a white solid (2-1). NMR (CDCl3): δ7.49 (5H, br s), 6.96 (1H, s), 4.17 (3H, s).

1. customThe solvent was evaporated
2. dissolutionthe residue dissolved in methylene chloride
3. washwashed with aq. NaHCO4
4. dry with materialthe organic layer dried over anhydrous Na2SO4
5. filtrationfiltered
6. customevaporated
7. customto give
8. additiona 2:1 mixture of isomeric products
9. washUpon chromatography on silica gel and elution with 15% ethyl acetate/hexane
10. custommajor isomer was isolated