GENERAL STEPS: DMSO (2.0 mL) was added to a 25 mL Schlenk tube protected by nitrogen and equipped with a magnetic stirrer. 2-Bromobenzylamine (1) (0.5 mmol), guanidine hydrochloride (2) (1.0 mmol), CuBr (0.1 mmol, 14.2 mg) and K2CO3 (1.5 mmol, 207 mg) were added sequentially. The reaction mixture was stirred at 80-120 °C for 24 h, followed by continued stirring for 0.5 h in air. After completion of the reaction, the mixture was cooled to room temperature, filtered, and the solid fraction was washed with ethyl acetate (3 x 3 mL). The filtrates were combined and concentrated by rotary evaporator and the residue was purified by silica gel column chromatography using petroleum ether/ethyl acetate as eluent to give the target product 2-aminoquinazoline.
