[CH2:1]([C:3]1[C:4]([O:23][CH3:24])=[N:5][C:6]2[N:7]([CH:10]=[C:11]([CH:13]([C:15]3[CH:20]=[CH:19][C:18]([O:21][CH3:22])=[CH:17][CH:16]=3)[OH:14])[N:12]=2)[C:8]=1[CH3:9])[CH3:2]>C(Cl)(Cl)Cl.[O-2].[O-2].[Mn+4]>[CH2:1]([C:3]1[C:4]([O:23][CH3:24])=[N:5][C:6]2[N:7]([CH:10]=[C:11]([C:13]([C:15]3[CH:20]=[CH:19][C:18]([O:21][CH3:22])=[CH:17][CH:16]=3)=[O:14])[N:12]=2)[C:8]=1[CH3:9])[CH3:2]10 g of activated manganese dioxide were added to a solution of 2.2 g (6.7 mmol) of (6-ethyl-7-methoxy-5-methyl imidazo[1,2-a]pyrimidin-2-yl)(4-methoxyphenyl)methanol in 100 ml of chloroform and the mixture was stirred at room temperature for 18 hours. The mixture was filtered through celite and evaporation of the filtrate gave a solid product. Purification on a 100 g silica gel column using chloroform-methanol (98 to 2) as the eluant gave 1.3 g (59% yield) of pure (6-ethyl-7-methoxy-5-methylimidazo[1,2-a]pyrimidin-2-yl)(4-methoxyphenyl)methanone as a white crystalline solid melting at 196°-7° C. Overall yield from ester was 37%.
読み込み中…