[S:1]1[CH:5]=[CH:4][CH:3]=[CH:2]1.C([Li])CCC.CCCCCC.[CH3:17][C:18]1[CH:23]=[CH:22][C:21]([C:24]2[C:25]([Cl:31])=[N:26][CH:27]=[N:28][C:29]=2[Cl:30])=[CH:20][CH:19]=1.ClC1C(=O)C(C#N)=C(C#N)C(=O)C=1Cl.C>O1CCCC1.O.C(O)(=O)C>[CH3:17][C:18]1[CH:19]=[CH:20][C:21]([C:24]2[C:29]([Cl:30])=[N:28][C:27]([C:2]3[S:1][CH:5]=[CH:4][CH:3]=3)=[N:26][C:25]=2[Cl:31])=[CH:22][CH:23]=1To a solution of thiophene (1.69 g) in anhydrous tetrahydrofuran (20 ml) is added dropwise a 1.6M n-butyl lithium/n-hexane solution (11.4 ml) at 0° C. under argon atmosphere over a period of 30 minutes. To the mixture is added dropwise and gradually a solution of 5-(4-methylphenyl)-4,6-dichloropyrimidine (4.0 g) in anhydrous tetrahydrofuran (5 ml) at -60° C. The mixture is warmed to 0° C., and stirred for 1.5 hour. After the reaction is complete, to the mixture are added acetic acid (1.5 g) and water (0.25 g), and further added thereto a solution of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (5.70 g) in tetrahydrofuran (5 ml), and the mixture is stirred at 0° C. for one hour. The mixture is treated with an active charcoal, and extracted with a mixture of ethyl acetate and aqueous citric acid solution. The extract is washed, dried and evaporated to remove the solvent. The residue is purified by silica gel column chromatography (solvent; n-hexane/ethyl acetate=50:1) to give 5-(4-methylphenyl)-4,6-dichloro-2-(2-thienyl)pyrimidine (2.64 g) as powder.
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