1: 1.) sodium amide / 1.) Et2O, liquid ammonia, -50 deg C - -40 deg C, 60 min, 2.) -50 deg C - -40 deg C, 100 min 2: toluene-p-sulphonic acid / methanol / 0.5 h / 70 °C 3: 91 percent / cerium(IV) ammonium nitrate / acetonitrile; H2O / 0.67 h / 0 - 2 °C View Scheme

1: 1.) sodium amide / 1.) Et2O, liquid ammonia, -50 deg C - -40 deg C, 60 min, 2.) -50 deg C - -40 deg C, 100 min 2: toluene-p-sulphonic acid / methanol / 0.5 h / 70 °C View Scheme