1: 1H-indole-2-carbaldehyde With sodium hydride in N,N-dimethyl-formamide; mineral oil Cooling with ice; 2: benzyl bromide in N,N-dimethyl-formamide; mineral oil T=20°C; Cooling with ice;

1: With cyanoborohydride on polymer support; acetic acid in tetrahydrofuran T=20°C; 15 h; 2: With ammonia in tetrahydrofuran; methanol

1: With cyanoborohydride on polymer support; sodium acetate; acetic acid in methanol; water 12.1667 h; 2: With ammonia in methanol

1.1: 99 percent / NH2OH*HCl; aq. Na2CO3 / ethanol / 0.5 h / Heating 2.1: NaBH4; NiCl2*6H2O / methanol / 0.08 h / 20 °C 3.1: Et3N; pyridine / 1 h / 3 °C 3.2: 234 mg / 16 h / 3 °C View Scheme

hydroxylamine hydrochloride; sodium carbonate in ethanol 0.5 h; Heating;

1.1: lithium hexamethyldisilazane / tetrahydrofuran / -40 °C / |Inert atmosphere 1.2: -78 - 25 °C / |Inert atmosphere 2.1: palladium 10 on activated carbon; hydrogen / ethanol / 20 °C View Scheme

1: Methyltriphenylphosphonium bromide With potassium hexamethylsilazane in tetrahydrofuran; toluene T=20°C; 0.5 h; 2: 1H-indole-2-carbaldehyde in tetrahydrofuran; toluene T=20°C; Wittig reaction; 2 h;

sodium hydride in tetrahydrofuran; mineral oil T=0 - 20°C; Wittig Rearrangement; 16 h;

1: 80 percent / triethylamine, NaBH3CN / ethanol / 14 h / Ambient temperature 2: 99 percent / ethyl formate / 12 h / Ambient temperature 3: 75 percent / methanesulfonic acid / 3.5 h / 70 °C / other reagent: polyphosphoric acid 4: 72 percent / p-toluenesulfonic acid monohydrate, chloranil / benzene / 12 h / Ambient temperature; other reactant: 9-benzyl-2-formyl-4-oxo-1,2,3,4-tetrahydro-β-carboline, other reagent: benzoquinone, other reaction time 5: 74 percent / m-chloroperbenzoic acid / CH2Cl2 / 24 h / Ambient temperature 6: 61 percent / triethylamine / acetonitrile / 5 h / 70 °C 7: 97 percent / KOH / acetonitrile; H2O / 14 h / Ambient temperature 8: 90 percent / HCl / CH2Cl2 / 1.) room temperature, 24 h, 2.) reflux, 10 h View Scheme

1.1: benzene / 4 h / Heating 2.1: methyl iodide / benzene / 2 h / Heating 2.2: MeONa / methanol / 4 h / Heating 3.1: 0.56 g / KOH; I2 / dimethylformamide / 4 h / 20 °C View Scheme