13726-16-4

D. General procedure for synthesizing 4-chloro-3-methoxybenzaldehyde: Manganese dioxide (5.65 g, 65 mmol) was added to a solution of (4-chloro-3-methoxyphenyl)methanol (5.08 g, 29.4 mmol) in benzene (120 mL). The reaction mixture was refluxed for 17 h. After cooling, the reaction mixture was filtered through diatomaceous earth and the filter cake was washed with dichloromethane (300 mL). The filtrate was concentrated under reduced pressure to give 4-chloro-3-methoxybenzaldehyde (4.5 g, 89% yield).

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