lithium sodium in diethyl ether 3 h;

1: 80 percent / triphenylphosphine, bromine, pyridine / benzene / 5 h / 0 - 22 °C 2: 65 percent / 2percent sodium in lithium alloy / diethyl ether / 3 h View Scheme

1: 72 percent / tert-butoxide, 18-crown-6 ether / tetrahydrofuran / 1.85 h / Heating 2: 80 percent / triphenylphosphine, bromine, pyridine / benzene / 5 h / 0 - 22 °C 3: 65 percent / 2percent sodium in lithium alloy / diethyl ether / 3 h View Scheme