in water T=45°C; 72 h;

water; trifluoroacetic acid; zinc in dichloromethane T=20°C;

1: triethylamine / dichloromethane / 24 h / 0 - 20 °C / |Inert atmosphere 2: tetrakis(triphenylphosphine) palladium(0); isopropylamine; copper(l) iodide / ethylene glycol dimethyl ether / 3.5 h / 70 °C / |Inert atmosphere 3: hydrogen; palladium 10 on activated carbon / ethyl acetate / 0.75 h / |Inert atmosphere 4: diisobutylaluminium hydride / tetrahydrofuran / 0.25 h / 0 °C 5: dimethyl sulfoxide; sulfur trioxide pyridine complex; triethylamine / dichloromethane / 2 h / 0 °C 6: sodium acetate; hydroxylamine hydrochloride / isopropyl alcohol / 1.5 h / 20 °C 7: Acid orange 52; sodium cyanoborohydride; hydrogenchloride / methanol / 1 h / 20 °C 8: sodium cyanoborohydride / tert-butyl alcohol / 16 h / |Inert atmosphere; |Sealed tube; |Microwave irradiation 9: zinc; trifluoroacetic acid; water / dichloromethane / 20 °C View Scheme

1: N-bromosuccinmide / dichloromethane / 2 h / 0 °C / |Inert atmosphere 2: 4-(N,N-dimethlyamino)pyridine / dichloromethane / 0.5 h / 20 °C 3: tetrakis(triphenylphosphine) palladium(0); isopropylamine; copper(l) iodide / ethylene glycol dimethyl ether / 3.5 h / 70 °C / |Inert atmosphere 4: hydrogen; palladium 10 on activated carbon / ethyl acetate / 0.75 h / |Inert atmosphere 5: diisobutylaluminium hydride / tetrahydrofuran / 0.25 h / 0 °C 6: dimethyl sulfoxide; sulfur trioxide pyridine complex; triethylamine / dichloromethane / 2 h / 0 °C 7: sodium acetate; hydroxylamine hydrochloride / isopropyl alcohol / 1.5 h / 20 °C 8: Acid orange 52; sodium cyanoborohydride; hydrogenchloride / methanol / 1 h / 20 °C 9: sodium cyanoborohydride / tert-butyl alcohol / 16 h / |Inert atmosphere; |Sealed tube; |Microwave irradiation 10: zinc; trifluoroacetic acid; water / dichloromethane / 20 °C View Scheme

1: hydrogenchloride / 2.5 h / 110 °C 2: N-bromosuccinmide / dichloromethane / 2 h / 0 °C / |Inert atmosphere 3: 4-(N,N-dimethlyamino)pyridine / dichloromethane / 0.5 h / 20 °C 4: tetrakis(triphenylphosphine) palladium(0); isopropylamine; copper(l) iodide / ethylene glycol dimethyl ether / 3.5 h / 70 °C / |Inert atmosphere 5: hydrogen; palladium 10 on activated carbon / ethyl acetate / 0.75 h / |Inert atmosphere 6: diisobutylaluminium hydride / tetrahydrofuran / 0.25 h / 0 °C 7: dimethyl sulfoxide; sulfur trioxide pyridine complex; triethylamine / dichloromethane / 2 h / 0 °C 8: sodium acetate; hydroxylamine hydrochloride / isopropyl alcohol / 1.5 h / 20 °C 9: Acid orange 52; sodium cyanoborohydride; hydrogenchloride / methanol / 1 h / 20 °C 10: sodium cyanoborohydride / tert-butyl alcohol / 16 h / |Inert atmosphere; |Sealed tube; |Microwave irradiation 11: zinc; trifluoroacetic acid; water / dichloromethane / 20 °C View Scheme

1: 4-(N,N-dimethlyamino)pyridine / dichloromethane / 0.5 h / 20 °C 2: tetrakis(triphenylphosphine) palladium(0); isopropylamine; copper(l) iodide / ethylene glycol dimethyl ether / 3.5 h / 70 °C / |Inert atmosphere 3: hydrogen; palladium 10 on activated carbon / ethyl acetate / 0.75 h / |Inert atmosphere 4: diisobutylaluminium hydride / tetrahydrofuran / 0.25 h / 0 °C 5: dimethyl sulfoxide; sulfur trioxide pyridine complex; triethylamine / dichloromethane / 2 h / 0 °C 6: sodium acetate; hydroxylamine hydrochloride / isopropyl alcohol / 1.5 h / 20 °C 7: Acid orange 52; sodium cyanoborohydride; hydrogenchloride / methanol / 1 h / 20 °C 8: sodium cyanoborohydride / tert-butyl alcohol / 16 h / |Inert atmosphere; |Sealed tube; |Microwave irradiation 9: zinc; trifluoroacetic acid; water / dichloromethane / 20 °C View Scheme

1: tetrakis(triphenylphosphine) palladium(0); isopropylamine; copper(l) iodide / ethylene glycol dimethyl ether / 3.5 h / 70 °C / |Inert atmosphere 2: hydrogen; palladium 10 on activated carbon / ethyl acetate / 0.75 h / |Inert atmosphere 3: diisobutylaluminium hydride / tetrahydrofuran / 0.25 h / 0 °C 4: dimethyl sulfoxide; sulfur trioxide pyridine complex; triethylamine / dichloromethane / 2 h / 0 °C 5: sodium acetate; hydroxylamine hydrochloride / isopropyl alcohol / 1.5 h / 20 °C 6: Acid orange 52; sodium cyanoborohydride; hydrogenchloride / methanol / 1 h / 20 °C 7: sodium cyanoborohydride / tert-butyl alcohol / 16 h / |Inert atmosphere; |Sealed tube; |Microwave irradiation 8: zinc; trifluoroacetic acid; water / dichloromethane / 20 °C View Scheme

1: tetrakis(triphenylphosphine) palladium(0); isopropylamine; copper(l) iodide / ethylene glycol dimethyl ether / 3.5 h / 70 °C / |Inert atmosphere 2: hydrogen; palladium 10 on activated carbon / ethyl acetate / 0.75 h / |Inert atmosphere 3: diisobutylaluminium hydride / tetrahydrofuran / 0.25 h / 0 °C 4: dimethyl sulfoxide; sulfur trioxide pyridine complex; triethylamine / dichloromethane / 2 h / 0 °C 5: sodium acetate; hydroxylamine hydrochloride / isopropyl alcohol / 1.5 h / 20 °C 6: Acid orange 52; sodium cyanoborohydride; hydrogenchloride / methanol / 1 h / 20 °C 7: sodium cyanoborohydride / tert-butyl alcohol / 16 h / |Inert atmosphere; |Sealed tube; |Microwave irradiation 8: zinc; trifluoroacetic acid; water / dichloromethane / 20 °C View Scheme

1: hydrogen; palladium 10 on activated carbon / ethyl acetate / 0.75 h / |Inert atmosphere 2: diisobutylaluminium hydride / tetrahydrofuran / 0.25 h / 0 °C 3: dimethyl sulfoxide; sulfur trioxide pyridine complex; triethylamine / dichloromethane / 2 h / 0 °C 4: sodium acetate; hydroxylamine hydrochloride / isopropyl alcohol / 1.5 h / 20 °C 5: Acid orange 52; sodium cyanoborohydride; hydrogenchloride / methanol / 1 h / 20 °C 6: sodium cyanoborohydride / tert-butyl alcohol / 16 h / |Inert atmosphere; |Sealed tube; |Microwave irradiation 7: zinc; trifluoroacetic acid; water / dichloromethane / 20 °C View Scheme

1: diisobutylaluminium hydride / tetrahydrofuran / 0.25 h / 0 °C 2: dimethyl sulfoxide; sulfur trioxide pyridine complex; triethylamine / dichloromethane / 2 h / 0 °C 3: sodium acetate; hydroxylamine hydrochloride / isopropyl alcohol / 1.5 h / 20 °C 4: Acid orange 52; sodium cyanoborohydride; hydrogenchloride / methanol / 1 h / 20 °C 5: sodium cyanoborohydride / tert-butyl alcohol / 16 h / |Inert atmosphere; |Sealed tube; |Microwave irradiation 6: zinc; trifluoroacetic acid; water / dichloromethane / 20 °C View Scheme