General procedure for the synthesis of 3-bromo-2-nitrobenzaldehyde from 3-bromo-2-nitrobenzenemethanol: 14.0 g of 3-bromo-2-nitrobenzenemethanol and 150 mL of 1,2-dichloroethane were added to a three-necked flask, followed by 42.0 g of manganese dioxide. The mixture was heated to reflux. After completion of the reaction, the reaction mixture was filtered through diatomaceous earth and the filtrate was concentrated. Purification by column chromatography separation resulted in 9.4 g (67.7% yield) of 3-bromo-2-nitrobenzaldehyde.
