hydrogen; Lindlar's catalyst in tetrahydrofuran T=21°C; 18 h;

1: 90 percent / 1.) magnesium, iodine; 2.) CuBr / diethyl ether / 1.) 2.5 h, 34-36 degC; 2.) -30 degC, 5 min, allowed to warm to 0 degC over 1 h, 3 h, 0 degC 2: thionylchloride, pyridine / 7.5 h / Heating 3: 78 percent / sodium azide / dimethylsulfoxide / 8 h / 75 °C 4: 67 percent / hydrogen / 5percent Pd/CaCO3 / tetrahydrofuran / 18 h / 21 °C View Scheme

1: thionylchloride, pyridine / 7.5 h / Heating 2: 78 percent / sodium azide / dimethylsulfoxide / 8 h / 75 °C 3: 67 percent / hydrogen / 5percent Pd/CaCO3 / tetrahydrofuran / 18 h / 21 °C View Scheme

1: 78 percent / sodium azide / dimethylsulfoxide / 8 h / 75 °C 2: 67 percent / hydrogen / 5percent Pd/CaCO3 / tetrahydrofuran / 18 h / 21 °C View Scheme