1: 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 2: 74 percent / m-chloroperbenzoic acid / CH2Cl2 / 24 h / Ambient temperature 3: 61 percent / triethylamine / acetonitrile / 5 h / 70 °C 4: 97 percent / KOH / acetonitrile; H2O / 14 h / Ambient temperature 5: 90 percent / HCl / CH2Cl2 / 1.) room temperature, 24 h, 2.) reflux, 10 h View Scheme

1: 61 percent / triethylamine / acetonitrile / 5 h / 70 °C 2: 97 percent / KOH / acetonitrile; H2O / 14 h / Ambient temperature 3: 90 percent / HCl / CH2Cl2 / 1.) room temperature, 24 h, 2.) reflux, 10 h View Scheme

1: 75 percent / methanesulfonic acid / 3.5 h / 70 °C / other reagent: polyphosphoric acid 2: 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 3: 74 percent / m-chloroperbenzoic acid / CH2Cl2 / 24 h / Ambient temperature 4: 61 percent / triethylamine / acetonitrile / 5 h / 70 °C 5: 97 percent / KOH / acetonitrile; H2O / 14 h / Ambient temperature 6: 90 percent / HCl / CH2Cl2 / 1.) room temperature, 24 h, 2.) reflux, 10 h View Scheme

2: 65 percent / lithium diisopropylamide / tetrahydrofuran; hexane / 1.) -50 deg C, 2 h, 2.) room temperature, 3 h 3: 74 percent / m-chloroperbenzoic acid / CH2Cl2 / 24 h / Ambient temperature 4: 61 percent / triethylamine / acetonitrile / 5 h / 70 °C 5: 97 percent / KOH / acetonitrile; H2O / 14 h / Ambient temperature 6: 90 percent / HCl / CH2Cl2 / 1.) room temperature, 24 h, 2.) reflux, 10 h View Scheme

1: 65 percent / lithium diisopropylamide / tetrahydrofuran; hexane / 1.) -50 deg C, 2 h, 2.) room temperature, 3 h 2: 74 percent / m-chloroperbenzoic acid / CH2Cl2 / 24 h / Ambient temperature 3: 61 percent / triethylamine / acetonitrile / 5 h / 70 °C 4: 97 percent / KOH / acetonitrile; H2O / 14 h / Ambient temperature 5: 90 percent / HCl / CH2Cl2 / 1.) room temperature, 24 h, 2.) reflux, 10 h View Scheme

1: 99 percent / ethyl formate / 12 h / Ambient temperature 2: 75 percent / methanesulfonic acid / 3.5 h / 70 °C / other reagent: polyphosphoric acid 3: 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 4: 74 percent / m-chloroperbenzoic acid / CH2Cl2 / 24 h / Ambient temperature 5: 61 percent / triethylamine / acetonitrile / 5 h / 70 °C 6: 97 percent / KOH / acetonitrile; H2O / 14 h / Ambient temperature 7: 90 percent / HCl / CH2Cl2 / 1.) room temperature, 24 h, 2.) reflux, 10 h View Scheme

1: 1.) LiAlH4, 2.) MnO2 / 1.) THF, RT, 2.) CH2Cl2, RT 2: 1.) NaBH3CN / 1.) MeOH, RT, 2.) RT 3: 67 percent / PPA / 60 °C 4: 69 percent / TsOH, chloranil / benzene / Ambient temperature 5: 81 percent / m-CPBA / CH2Cl2 / Ambient temperature 6: 50 percent / Et3N / dioxane / Heating 7: 100 percent / KOH / acetonitrile; H2O / Ambient temperature 8: 90 percent / HCl / methanol / Ambient temperature View Scheme

1.1: 70 percent / DIBALH / CH2Cl2 / 0.08 h / -40 °C 2.1: HMDS; n-BuLi / tetrahydrofuran; hexane / 0.25 h / -78 °C 2.2: tetrahydrofuran; hexane / 0.25 h / -78 °C 2.3: 88 percent / EtOH / tetrahydrofuran; hexane / 0.5 h / 20 °C View Scheme