1: 39 percent / bis(triphenylphosphine)palladium (II) chloride / hexamethylphosphoric acid triamide / 25 h / 65 °C 2: 1.) O3, 2.) Me2S / 1.) MeOH, CH2Cl2, -78 deg C, 10 min, 2.) -78 deg C to room temperature. View Scheme

dimethylsulfide; ozone 1.) MeOH, CH2Cl2, -78 deg C, 10 min, 2.) -78 deg C to room temperature.; Yield given. Multistep reaction;