1: 76.4 percent / acetonitrile / Ambient temperature 2: SnCl4 / CH2Cl2 / Ambient temperature 3: 1.) trimethylchlorosilane, Zn, 2.) acetic acid, Zn / 1.) CH2Cl2, RT, 1 h, 2.) CH2Cl2, 2 h 4: 64 percent / HBr, acetic acid, 70percent HClO4 / Ambient temperature View Scheme