One-pot synthesis from 1-(2-phenylquinolin-7-yl)-ethanone: The mixture of 1-(2-phenylquinolin-7-yl)-ethanone (50 mg, 0.20 mmol), malononitrile (40 mg, 0.60 mmol), sulfur (39 mg, 1.2 mmol), morpholine (0.12 ml), and formamide (1.0 ml) in a sealed tube was heated at 80° C. for 17 h under N2. LC-MS confirmed the formation of 2-amino-4-(2-phenylquinolin-7-yl)-thiophene-3-carbonitrile (MS (ES+): m/z 328.1 (100) [MH+]). The above mixture was then heated to 180° C. for 3 h. The cooled reaction mixture was poured into brine (10 ml) and extracted with EtOAc (3×15 ml). The combined organic extracts were washed with brine (10 ml), dried over MgSO4, filtered, and concentrated to give a brown oil. Purification by TLC on silica gel [eluting with EtOAc/hexane (40/60)], followed by HPLC gave the title compound as an off-white solid.
