1: 4-fluoro-1,3-dihydro-2H-indol-2-one With n-butyllithium; diisopropylamine in tetrahydrofuran T=-20 - 0°C; 2: ethylene dibromide in tetrahydrofuran T=0 - 20°C; 15 - 18 h;

N-bromosuccinmide in water; acetonitrile T=20 - 25°C; 2 h;

N-bromosuccinmide in water; acetonitrile T=0°C; 18 h;