1.1: Br2; Na2SO3 / CH2Cl2; methanol / -78 °C 2.1: 3.49 g / MeONa / methanol; tetrahydrofuran / 3 h / 0 - 20 °C 3.1: NaN[SiMe3]2 / tetrahydrofuran / 1 h / -78 °C 3.2: 86 percent / tetrahydrofuran / -78 - 20 °C 4.1: 90 percent / Pd(PPh3)2Cl2; CuI; Et3N / tetrahydrofuran / 0.5 h / 0 °C View Scheme