1: 2-(4-fluorophenyl)acetic acid With sodium hydroxide in N,N-dimethyl-formamide T=20°C; 1 h; 2: 2-bromo-l-(4-(methylsulfonyl)-phenyl)-ethanone in N,N-dimethyl-formamide 1 h; 3: With diisopropylamine in N,N-dimethyl-formamide T=60°C; 4 h;

4 A molecular sieve; toluene-4-sulfonic acid; triethylamine in acetonitrile 16 h; Heating;

hydrogenchloride; 1,8-diazabicyclo[5.4.0]undec-7-ene in hexane; ethyl acetate; acetonitrile

1: 91 percent / mCPBA / CH2Cl2 / Ambient temperature 2: 15.7 g / HCl, bromine / acetic acid 3: 68 percent / triethylamine / acetonitrile / 0.5 h / Ambient temperature 4: 94 percent / triethylamine, p-toluenesulfonic acid, 4 Angstroem molecular sieves / acetonitrile / 16 h / Heating View Scheme

1: 15.7 g / HCl, bromine / acetic acid 2: 68 percent / triethylamine / acetonitrile / 0.5 h / Ambient temperature 3: 94 percent / triethylamine, p-toluenesulfonic acid, 4 Angstroem molecular sieves / acetonitrile / 16 h / Heating View Scheme

1: 68 percent / triethylamine / acetonitrile / 0.5 h / Ambient temperature 2: 94 percent / triethylamine, p-toluenesulfonic acid, 4 Angstroem molecular sieves / acetonitrile / 16 h / Heating View Scheme

1: 98.5 percent / tetrahydrofuran; diethyl ether / 1.) -78 deg C - RT, 2.) RT, 2.5 h 2: 91 percent / mCPBA / CH2Cl2 / Ambient temperature 3: 15.7 g / HCl, bromine / acetic acid 4: 68 percent / triethylamine / acetonitrile / 0.5 h / Ambient temperature 5: 94 percent / triethylamine, p-toluenesulfonic acid, 4 Angstroem molecular sieves / acetonitrile / 16 h / Heating View Scheme

1: 58 percent / oxone; H2O / tetrahydrofuran; methanol / 4 h / 20 °C View Scheme

1.1: NaNO2; HCl / 0 °C 1.2: KI / 80 °C 2.1: 58 percent / oxone; H2O / tetrahydrofuran; methanol / 4 h / 20 °C View Scheme

1.1: AlCl3, aluminium chloride / chloroform / 1.5 h / -5 - 5 °C / |Cooling with ice 2.1: acetic acid; dihydrogen peroxide; sulfuric acid / 2 h / 0 - 70 °C 3.1: acetic acid; hydrogen bromide / 0.08 h / 20 °C 3.2: 2.5 h / 25 - 58 °C 4.1: sodium hydroxide / N,N-dimethyl-formamide / 1 h / 20 °C 4.2: 1 h 4.3: 4 h / 60 °C View Scheme