[F:1][C:2]1[CH:7]=[CH:6][C:5]([C:8](=[O:18])[CH2:9][C:10]2[CH:15]=[CH:14][N:13]=[C:12]([S:16][CH3:17])[N:11]=2)=[CH:4][CH:3]=1.[N:19](OC(C)(C)C)=[O:20].Cl>C(O)C.C(O)CC>[F:1][C:2]1[CH:7]=[CH:6][C:5]([C:8](=[O:18])/[C:9](=[N:19]\[OH:20])/[C:10]2[CH:15]=[CH:14][N:13]=[C:12]([S:16][CH3:17])[N:11]=2)=[CH:4][CH:3]=1To a suspension of 1-(4-fluorophenyl)-2-(2-(methylthio)pyrimidin-4-yl)ethanone, 73 (1.0 g) in ethanol (20 mL) at −10° C., under an atmosphere of nitrogen, is added dropwise t-butyl nitrite (0.5 mL) followed by hydrogen chloride in n-propanol (2.5 to 3 N, 0.6 mL) while maintaining the temperature below −5° C. Once the addition is complete, the solution is allowed to warm to room temperature with stirring and after 2 h the solvent is evaporated and the residue partitioned between saturated aqueous sodium hydrogen carbonate and ethyl acetate. The layers are separated; the aqueous phase is extracted with ethyl acetate and the combined organic phases dried over sodium sulfate. Filtration and evaporation of the solvent affords the title compound, 74 (1.0 g).
Wird geladen…
