sodium hydroxide; sodium hypochlorite in water T=20 - 45°C; 6.5 h;

trifluoroacetic acid in dichloromethane T=45°C; 1 h;

iron; ammonium chloride in tetrahydrofuran; ethanol; water 5 h; Reflux;

1: diphenylphosphoranyl azide; triethylamine / toluene / 2 h / 90 °C 2: trifluoroacetic acid / dichloromethane / 1 h / 45 °C View Scheme

1.1: N-ethyl-N,N-diisopropylamine / tetrahydrofuran / 7 h / |Reflux 2.1: hydrogen; platinum(IV) oxide / tetrahydrofuran; methanol / 1 h 3.1: hydrogen; 5 palladium on charcoal / tetrahydrofuran; methanol / 2 h / 20 °C 3.2: 10 h / 110 °C View Scheme