1: sodium acetate; acetic acid; bromine / 4 h / 45 °C / |Inert atmosphere 2: sodium azide / N,N-dimethyl-formamide / 5 h / 45 °C / |Inert atmosphere 3: zinc; ammonium chloride / ethyl acetate; methanol / 0.5 h / 20 - 60 °C / |Inert atmosphere 4: (2R,3S)-(-)-di-O-benzoyl tartaric acid / isopropyl alcohol / 18 h / 20 - 85 °C / |Inert atmosphere View Scheme

bromine; sodium acetate; acetic acid T=40 - 42°C; 1 h;