potassium hydroxide; Triton X-405 in water T=60°C; 2 h;

aluminum oxide 24 h; Ambient temperature;

1: 69 percent / 4-(N,N-dimethylamino)pyridine; acetic anhydride / diethyl ether / 20 °C 2: 91 percent / 18-crown-6 / tetrahydrofuran / 0.5 h / -78 °C 3: 70 percent / α,α'-azobisisobutyronitrile; tributyltin hydride / toluene / 2 h / Heating 4: lithium; liq. ammonia / tetrahydrofuran; 2-methyl-propan-2-ol / 0.33 h / -78 °C View Scheme

T=380.7°C; P=84 Torr; Kinetics; Further Variations:PressuresTemperaturesalso in the presence of free radical inhibitors;

aluminium amalgam; water

1: (i) AcCl, (ii) benzene, Na2CO3 2: H2 / Pt / tetrahydrofuran View Scheme

1: H2SO4 / CH2Cl2 / Ambient temperature 2: 70 percent / DBU / tetrahydrofuran / 10 h / Ambient temperature View Scheme