boron trifluoride diethyl etherate in dichloromethane T=25°C; 24 h;

1.1: 90 percent / phosphoric tribromide / 0.5 h / 150 °C 2.1: diisopropylamine; butyllithium / tetrahydrofuran; hexane / 2 h / -75 °C 2.2: 98 percent / tetrahydrofuran; hexane / 2 h 3.1: 97 percent / BF3*OEt2 / CH2Cl2 / 24 h / 25 °C View Scheme

1.1: diisopropylamine; butyllithium / tetrahydrofuran; hexane / 2 h / -75 °C 1.2: 98 percent / tetrahydrofuran; hexane / 2 h 2.1: 97 percent / BF3*OEt2 / CH2Cl2 / 24 h / 25 °C View Scheme

1: 2-bromo-4-(1,3-dioxolan-2-yl)-3-fluoroquinoline With n-butyllithium in tetrahydrofuran; diethyl ether; hexane T=-100°C; 6 h; 2: carbon dioxide in tetrahydrofuran; diethyl ether; hexane