1: indole With ethylmagnesium bromide in tetrahydrofuran; diethyl ether; toluene T=20°C; 1 h; 2: C12H9Cl2NO3 in tetrahydrofuran; diethyl ether; toluene 4 h; Heating / reflux; 3: in tetrahydrofuran; diethyl ether; toluene T=20°C;

bromine in tetrahydrofuran; dichloromethane T=0°C; 2 h;