1: 5-fluoro-1H-indole; acetic anhydride With ammonium chloride in 1,2-dichloro-ethane T=20°C; 2 h; 2: acetic anhydride With aluminium trichloride in 1,2-dichloro-ethane 0.5 h; Further stages.;

trichlorophosphate T=20°C; Vilsmeier Reaction; 12 h; Cooling with ice;

1: 1.) AlCl3 / 1.) CH2Cl2, 25 deg C, 15 min, 2.) CH2Cl2, 25 deg C, 2 h 2: 85 percent / K2CO3 / methanol; H2O / 2 h / Heating View Scheme

1.1: sodium hydroxide / ethanol / 3 h / Reflux 1.2: pH 5 / Cooling with ice 2.1: quinoline; copper / 3 h / Neat (no solvent); Reflux 3.1: acetic acid / 20 h / Reflux View Scheme

1.1: acetic acid / ethanol / Reflux 2.1: polyphosphoric acid / 4 h / 100 °C 3.1: sodium hydroxide / ethanol / 3 h / Reflux 3.2: pH 5 / Cooling with ice 4.1: quinoline; copper / 3 h / Neat (no solvent); Reflux 5.1: acetic acid / 20 h / Reflux View Scheme

1.1: hydrogenchloride / water / 2 h / 20 °C 1.2: 1 h / 5 °C 2.1: acetic acid / ethanol / Reflux 3.1: polyphosphoric acid / 4 h / 100 °C 4.1: sodium hydroxide / ethanol / 3 h / Reflux 4.2: pH 5 / Cooling with ice 5.1: quinoline; copper / 3 h / Neat (no solvent); Reflux 6.1: acetic acid / 20 h / Reflux View Scheme

1: quinoline; copper / 3 h / Neat (no solvent); Reflux 2: acetic acid / 20 h / Reflux View Scheme