Preparation method of 2-bromo-6-nitrotoluene_Kain Industrial Additive

background and overview[1][2] 2-bromo-6-nitrotoluene can be used as a pharmaceutical synthesis intermediate. preparation[1] 2-bromo-6-nitrotoluene is prepared as follows: ① preparation of 3-nitro-4-methylbenzenesulfonic acid: place 100kg p-toluenesulfonic acid and 319kg concentrated sulfuric acid into the reaction kettle, stir for 1.5 hours, and slowly add 65% concentrated nitric acid while stirring 61.8kg, keep the temperature at 30-40°c…