General procedure: Catalyst 1 (10 mol%), 2-bromo-5-nitroaniline (1.0 mmol), tetramethylammonium chloride (Me4NCl, 2.0 mmol) and ethanol (EtOH, 2.0 mL) were sequentially added to the Schlenk tube under nitrogen protection. The Schlenk tube was sealed using a polytetrafluoroethylene (Teflon) valve and the reaction mixture was stirred at 100 °C for the reaction time referred to in Table 2 (the reaction process was monitored by gas chromatography (GC)). Upon completion of the reaction, the solvent was removed by distillation under reduced pressure. The resulting residue was purified by silica gel column chromatography (eluent: petroleum ether/ethyl acetate = 10/1) to give 2-chloro-5-nitroaniline. The product yield was determined by high-resolution gas chromatography-mass spectrometry (GC-MS) analysis, and the structure was confirmed by comparing its physical properties and spectral data with known compounds.
