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Part II- Synthesis of 4,6-dichloropyridine-3-carbaldehyde: (4,6-dichloropyridin-3-yl)methanol (4.9 g, 28 mmol) was dissolved in trichloromethane (100 mL). Subsequently, manganese dioxide (24 g, 280 mmol) was added and the reaction mixture was stirred at 75 °C for 12 hours. Upon completion of the reaction, the mixture was cooled to room temperature, filtered through a pad of diatomaceous earth and the filtrate was concentrated under reduced pressure to give 4,6-dichloropyridine-3-carbaldehyde. The mass of the product was 2.9 g in 90% yield. Liquid chromatography-mass spectrometry (electrospray ionization) analysis: calculated value C6H3Cl2NO = 175; measured value [M + H]+ signal is weak.

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