1: 22 percent / CH2Cl2 / 1 h / -78 °C / Irradiation 2: 45 percent / 1 h / Ambient temperature; Irradiation 3: potassium carbonate / ethane-1,2-diol / 4 h / 120 °C 4: 1.) N-bromosuccinimide (NBS), AIBN, 2.) NaI / 1.) carbon tetrachloride, 12 h, reflux, 2.) acetone, 2 h, reflux View Scheme

1: 45 percent / 1 h / Ambient temperature; Irradiation 2: potassium carbonate / ethane-1,2-diol / 4 h / 120 °C 3: 1.) N-bromosuccinimide (NBS), AIBN, 2.) NaI / 1.) carbon tetrachloride, 12 h, reflux, 2.) acetone, 2 h, reflux View Scheme

1: potassium carbonate / ethane-1,2-diol / 4 h / 120 °C 2: 1.) N-bromosuccinimide (NBS), AIBN, 2.) NaI / 1.) carbon tetrachloride, 12 h, reflux, 2.) acetone, 2 h, reflux View Scheme

N-bromosuccinmide; 2,2'-azo-bisisobutyronitrile; sodium iodide 1.) carbon tetrachloride, 12 h, reflux, 2.) acetone, 2 h, reflux; Multistep reaction;

ozone 1.) CH2Cl2, -78 deg C, 2.) CH2Cl2, -78 deg C, irradiation; Yield given. Multistep reaction;

ozone 1.) CH2Cl2, -78 deg C, 2.) CH2Cl2, -78 deg C, irradiation; Yield given. Multistep reaction;