CuBr2Li in tetrahydrofuran T=-60°C; 1 h;

1: sodium amide / diethyl ether; liquid ammonia / 5 h / -40 °C 2: pyridine / diethyl ether / 3 h View Scheme

1: sodium amide / diethyl ether; liquid ammonia / 5 h / -40 °C 2: pyridine / diethyl ether / 3 h 3: 93 percent / sodium hydride / tetrahydrofuran / 0.2 h / 20 °C / other temperature, time, base View Scheme