1: 72 percent / H2, potassium carbonate / Lindlar catalyst / toluene / 3 h / 20 °C / 760 Torr 2: PBr3 / diethyl ether / 0.08 h / Ambient temperature 3: 69 percent / benzene / Heating 4: 78 percent / NaOCH3 / CH2Cl2; methanol / 1 h / -10 °C View Scheme