Bromine → Methyl 3-bromomethyl-4-nitrobenzoate

Beteiligte Stoffe

Reaktionsschritte

In a 5-liter three-necked round-bottomed flask equipped with a reflux condenser, overhead stirrer, addition funnel and nitrogen inlet, was placed 220 g of methyl 3-methyl-4-nitrobenzoate, 2 l of anhydrous carbon tetrachloride and 4 g of benzoyl peroxide. To the resulting solution, irradiated with a 275 watt UV light, was added 198 g of bromine dropwise over a period of 2 hours at reflux. After the addition was complete the reaction mixture was refluxed for an additional 60 hours. The reaction mixture was cooled to room temperature. The solid which formed was separated by suction filtration. This solid (159.1 g) consisted of the expected methyl 3-bromomethyl-4-nitrobenzoate with minor amounts of the starting material. The mother liquors together with another 220 g of methyl 3-methyl-4-nitrobenzoate and 4 g of benzoyl peroxide were returned to the flask and treated with 198 g of bromine as described above. After the addition was complete the reaction mixture was refluxed another 96 hours, cooled to room temperature and the resulting solid separated by filtration yielding another 252 g of methyl 3-bromomethyl-4-nitrobenzoate. The solids were combined yielding a total of 411.1 g of methyl 3-bromomethyl-4-nitrobenzoate with minor amounts of the starting methyl 3-methyl-4-nitrobenzoate and methyl 3-dibromomethyl-4-nitrobenzoate. This solid was used as such in the next step.

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