[C:1]([C:9]1[CH:14]=[CH:13][N+:12]([O-])=[CH:11][CH:10]=1)(=[O:8])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.P(Cl)(Cl)([Cl:18])=O.[OH-].[Na+]>O>[C:1]([C:9]1[CH:14]=[CH:13][N:12]=[C:11]([Cl:18])[CH:10]=1)(=[O:8])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1A mixture of 2.5 g 4-benzoylpyridine N-oxide m.p. 127°-30° C. (obtained according to T. KATO et. al., Yakugaku Zasshi 86, 1022-26, 1966), and 6 ml phosphorus oxychloride is refluxed for 2 hrs. After cooling, the reaction mixture is very slowly added to ice:water, basified (10N NaOH) and extracted with methylene chloride. The organic layer is washed with water, dried and solvent removed in a rotary evaporator. Yield: 2.4 g of title product, identical with that described in Ex. 4.
Wird geladen…