5C6H5-CH3+6KMnO4+9H2SO4---5C6H5-COOH+3K2SO4+6MnSO4+14H2O,C6H5-COOH+Cl2---Cl-C6H4-COOH（间氯苯甲酸）+HCl,Cl-C6H4-COOH+CH3MgCl----CH3-C6H4-COOH(间甲基苯甲酸)+MgCl2
