Synthesis
Add 1/3 kettle capacity of carbon tetrachloride solvent and measured azodiisobutyronitrile, 48% hydrogen bromide to the reaction kettle, stirring and heated with steam; heated to about 75 , at the same time, drop-addition of measured o-nitrotoluene and 30% hydrogen peroxide, to keep the temperature does not drop to maintain reflux, drop-addition time of about 3-4 hours; drop-addition is completed, continue to hold the reflux reaction for 1-2 hours, turn off the steam, reduce the temperature to Room temperature, take samples to analyze the content of o-nitrobenzyl bromide: liquid separation, the organic layer is washed three times with 20% NaHSO3 aqueous solution and water, and then distilled at atmospheric pressure to remove the carbon tetrachloride solvent; petroleum ether is used for recrystallization of the reaction solution, and then centrifuged the crystals, and cold petroleum ether is used for rinsing, and then the solid product of o-nitrobenzyl bromide is obtained as white color.
