The general procedure for the synthesis of toluene and 2-bromophenylhydrazine from 2-bromotoluene was as follows: in an 8 mL screw-capped test tube, the indicated amounts of CuBr, ligand, phase transfer catalyst (PTC), and 50 mg of water were mixed well. Subsequently, 1 mmol of aryl halide and 10 mol% of the indicated amount of base were added, and the resulting mixture was stirred at a set temperature (bath temperature) for 10 min. Next, the remaining amount of base and the specified amount of hydrazine hydrate (N2H4-H2O) were added. The reaction mixture was continued to be stirred in a closed test tube at the same temperature for 1 hour. After completion of the reaction, it was cooled to room temperature and extracted with 5 mL of ethyl acetate (EtOAc). A 0.1 to 0.2 mL sample of the organic phase was dried over anhydrous sodium sulfate (Na2SO4) and analyzed by gas chromatography (GC).
