Bromine benzyl ammonium drug intermediates adjacent bromine toluene synthesis method

摘要

#$%^&*AU2016102199A420170216.pdf#####ABSTRACT Bromine benzyl ammonium drug intermediates adjacent bromine toluene synthesis method, comprising the following steps: 0.Imol sulfate crystals was added in reaction vessel, and a quantity of metal powder, 0.6-0.8mol potassium bromide crystals, 1100-1500ml water, 18-21mol concentrated sulfuric acid, maintaining reflux for 2-2.5h, followed by addition of sodium bisulfite 3-8g, obtain bromide salt solution as a backup; equipped with a stirrer, a thermometer, a dropping funnel, the reaction vessel was added 500-700mL water, 0.6-0.8mol o-toluidine, 2mol concentrated phosphoric acid solution with a mass fraction of 80% 90% was slowly added, the solution was heated and maintained the temperature at 85-90C, after sustained 30min, the solution temperature is reduced to 5-10 C, 0.8-0.9mol sodium hydrogen sulphate was added dropwise in solution, maintaining the reaction temperature at 12-20C ,generating diazonium salt (3) solution; the resulting bromide salt solution was heated to 90--95 C, the resulting diazonium salt (3) was added to it through a separatory funnel sticking below the liquid surface about 1-1.5cm, the duration of the process is 20-25min, and then steam distillation until no oil was distilled out, the distillate was adjusted to PH 8-9 by sodium carbonate solution with a mass fraction of 40%-50%, the separation of the crude o-bromotoluene washed with concentratedphosphoric acid with a mass fraction of 60%, washed with saline solution, dehydrated with dehydratingagent and distillation, collecting fractions of 185-195C, ultimately got o-bromotoluene.