1: 40 percent / ozone / CH2Cl2 / 3 h / -78 °C 2: 1.) Jones reagent, sodium hydroxide / 1.) acetone, 0 deg C, 15 min, 2.) methanol, RT, 1 h View Scheme

1: With ozone in dichloromethane T=-78°C; 2: With 1,8-diazabicyclo[5.4.0]undec-7-ene in dichloromethane T=-78 - 20°C; 8 h;