To a flame-dried 20-mL microwave vial equipped with a magnetic stir bar was added ethylenediammonium diacetate (201 mg, 1.1 mmol, 0.9 equiv), diketone 15-4 (260 mg, 1.2 mmol, 1.0 equiv), and aldehyde 10-7 (470 mg, 1.8 mmol, 1.5 equiv). The reaction vial was sealed with a Tefloncoated silicon microwave cap, and the reaction vial was evacuated and backfilled with nitrogen for three times. To the reaction mixture was added DCE (6.2 mL, 0.2 M), and the reaction vessel was then transferred to a room temperature sonication bath for 5 minutes. Following this, the reaction vessel was moved to a 65 °C preheated oil bath.