aluminium trichloride in dichloromethane T=-78°C; 6 h;

sodium azide; Dess-Martin periodane in dichloromethane T=25°C; 2.1 h;

4-(N,N-dimethlyamino)pyridine in benzene 24 h; Ambient temperature;

1: 95 percent / p-toluenesulfonic acid / benzene / Heating 2: 98 percent / lithium diisopropylamide / tetrahydrofuran / 2 h / -78 °C 3: aluminum chloride / CH2Cl2 / 6 h / -78 °C View Scheme

1: 98 percent / lithium diisopropylamide / tetrahydrofuran / 2 h / -78 °C 2: aluminum chloride / CH2Cl2 / 6 h / -78 °C View Scheme

1: 1,4-diazabicyclo<2.2.2>octane 2: 95 percent / p-toluenesulfonic acid / benzene / Heating 3: 98 percent / lithium diisopropylamide / tetrahydrofuran / 2 h / -78 °C 4: aluminum chloride / CH2Cl2 / 6 h / -78 °C View Scheme

1: 91 percent / 1,4-diazabicyclo<2.2.2>octane, n-butyllithium / tetrahydrofuran; hexane / 0 degC for 15 min and room t. for 1.5 h, then 0 degC, 1 h, room t., 1 h 2: 95 percent / p-toluenesulfonic acid / benzene / 7 h / Heating 3: 98 percent / lithium diisopropylamide / tetrahydrofuran / 4 h / -78 °C 4: 10 percent / aluminum chloride / CH2Cl2 / 6 h / -78 °C View Scheme

1: 50 percent / PhCOOH, LiClO4, alumina, MeCN, PhSH / acetonitrile / 2 h / constant current electrolysis: 100 mA, graphite cell, platine anode 2: 90 percent / 4-(dimethylamino)pyridine / benzene / 24 h / Ambient temperature View Scheme