1: 1.) LDA / 1.) THF, -78 deg C, 15 min.; 2.) HMPA, -78 deg C, 2h; room temp., 10h 2: 100 percent / LDA, HMPA / tetrahydrofuran / 1.) -78 deg C, 30 min.; 2.) room temp., 1h 3: 100 percent / 30percent H2O2 / CH2Cl2 4: 88 percent / sodium methoxide / methanol / 5 h / Ambient temperature 5: 95 percent / H2 / Lindlar catalyst / ethyl acetate / 760 Torr View Scheme

ozone; diethylamine in dichloromethane Heating;

copper(l) iodide in diethyl ether T=-20°C; 0.5 h;

in diethyl ether T=-78°C; 0.75 h;

in dichloromethane T=-78°C;

1: bromine / diethyl ether 2: 88.5 percent / diethyl ether / 0.75 h / -78 °C View Scheme

1: 92 percent / triethylamine, dimethylsulfoxide / diethyl ether / 4.5 h / Ambient temperature 2: 100 percent / 0.17 h / 600 °C 3: 88.5 percent / diethyl ether / 0.75 h / -78 °C View Scheme

1: 100 percent / PPTS / ethanol / 72 h / 55 °C 2: 92 percent / triethylamine, dimethylsulfoxide / diethyl ether / 4.5 h / Ambient temperature 3: 100 percent / 0.17 h / 600 °C 4: 88.5 percent / diethyl ether / 0.75 h / -78 °C View Scheme

ammonium chloride 1) Et2O, -20 deg C; Multistep reaction;

1: 100 percent / 0.17 h / 600 °C 2: 88.5 percent / diethyl ether / 0.75 h / -78 °C View Scheme