1: 82.4 percent / 2 N NaOH / aq. ethanol / 0.25 h / Heating 2: 72.9 percent / hydrogen / 10percent Pd/C / aq. ethanol / Ambient temperature 3: 38.7 percent / polyphosphoric acid / xylene / 100 deg C, 3 h; 110 deg C, 1 h View Scheme