trifluoroacetic acid in methanol T=0°C; Inert atmosphere;

sulfuric acid; periodic acid in water; acetonitrile T=20°C; 24 h; optical yield given as percent ee;

1: toluene / 24 h / 120 °C 2: (R)-3,3′-bis[3,5-bis(trifluoromethyl)phenyl]-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate; 2-(4-nitrophenyl)-2,3-dihydrobenzothiazole / dichloromethane / 24 h / 55 °C / Inert atmosphere 3: sulfuric acid; periodic acid / water; acetonitrile / 24 h / 20 °C View Scheme

1: (R)-3,3′-bis[3,5-bis(trifluoromethyl)phenyl]-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate; 2-(4-nitrophenyl)-2,3-dihydrobenzothiazole / dichloromethane / 24 h / 55 °C / Inert atmosphere 2: sulfuric acid; periodic acid / water; acetonitrile / 24 h / 20 °C View Scheme