[Cl:1][C:2]1[C:3]([C:9](=[O:11])[CH3:10])=[N:4][CH:5]=[C:6](Cl)[CH:7]=1.C(=O)([O-])[O-:13].[K+].[K+].C(=NO)C.O>CS(C)=O>[Cl:1][C:2]1[C:3]([C:9](=[O:11])[CH3:10])=[N:4][CH:5]=[C:6]([OH:13])[CH:7]=1To a solution of 3.8 g of the 1-(3,5-dichloropyridin-2-yl)ethanone prepared in Step 1 in Synthetic Example 2 and 13.8 g of potassium carbonate in 20 ml of dimethylsulfoxide, 5.9 g of acetaldoxime was added, and the mixture was stirred at 80° C. for 4 hours. After completion of the reaction, the reaction mixture was allowed to cool to room temperature, mixed with 50 ml of water and washed with diethyl ether (30 ml×1), the resulting aqueous layer was acidified with 6N aqueous hydrochloric acid and extracted with ethyl acetate (25 ml×2). The resulting organic layers were combined, dried over saturated aqueous sodium chloride and then anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure to obtain 1.0 g of desired crude product as brown crystals. The crystals were used in the next step without further purification.
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