1.1: triethylamine; 4-(N,N-dimethlyamino)pyridine / dichloromethane / |Cooling with ice 2.1: ammonium cerium (IV) nitrate / water; acetonitrile / 0.08 h / 0 °C 3.1: sodium hydroxide / dichloromethane / 0.5 h / 20 °C 3.2: 2 h / |Reflux View Scheme

1.1: (-)-Dibenzoyl-L-tartaric acid / isopropyl alcohol; water / 24 h / 20 °C 2.1: triethylamine; 4-(N,N-dimethlyamino)pyridine / dichloromethane / |Cooling with ice 3.1: ammonium cerium (IV) nitrate / water; acetonitrile / 0.08 h / 0 °C 4.1: sodium hydroxide / dichloromethane / 0.5 h / 20 °C 4.2: 2 h / |Reflux View Scheme