1: 91 percent / xylene / Heating 2: 1) ozone, 2) Me2S, 29percent aq. ammonia / 1) CH2Cl2, -60 deg C, 2) to room temperature View Scheme

1: 91 percent / xylene / Heating 2: 1) ozone, 2) dimethyl sulfide, water / 1) acetone, -60 deg C, 2) room temperature View Scheme