bromine; acetic acid T=20°C; 3 h;

1.1: NaH / tetrahydrofuran / 1.17 h / 0 - 20 °C 1.2: 89 percent / tetrahydrofuran / 22 h / 0 - 20 °C 2.1: 82 percent / bromine; AcOH / 3 h / 20 °C View Scheme