manganese(IV) oxide; trifluoroacetic acid T=20°C; Fischer indole cyclization; 2 h;

trifluoroacetic acid; sodium nitrite in acetonitrile T=20°C; 0.25 h;

manganese(IV) oxide; trifluoroacetic acid T=20°C; Fischer indole cyclization; 4.5 h;

air; iodine in benzene 24 h; Irradiation;

1: acetic anhydride; triethylamine / 24 h / |Reflux; |Inert atmosphere 2: sulfuric acid / |Inert atmosphere 3: anhydrous iron chloride; di-tert-butyl peroxide; trifluoroacetic acid / dichloromethane; nitromethane / 6 h / 20 °C / |Inert atmosphere View Scheme

hydrogenchloride Heating;