反应详情

30.8 g (0 1 mol) of 2-bromo-4-fluoro-3',5'-dimethylbenzophenone were dissolved in 140 g of 90% sulfuric acid, and 5.7 g of 90% hydrogen peroxide solution were added dropwise (metering time 1 h) between -10° C. and 0° C. After subsequent stirring for 2 h, the mixture was poured on to 500 g of ice and then heated at the boil for 5 h. Isolation as described in Example 8 gave 9.6 g (0.079 mol, 79%) of 3,5-dimethylphenol and 15.6 g (0.071 mol, 71%) of 2-bromo-4-fluorobenzoic acid (crude, purity (GC) ca. 90%, melting point 160°-166° C.)

1. temperatureheated at the boil for 5 h