1: 3,6-dibromo-9-(naphthalen-1-yl)-9H-carbazole With tert.-butyl lithium in tetrahydrofuran; pentane Inert atmosphereCooling with acetone-dry ice; 2: N,N-dimethyl-formamide in tetrahydrofuran; pentane 2 h; Inert atmosphereCooling with acetone-dry ice; 3: With hydrogenchloride; water in tetrahydrofuran; pentane T=20°C;

trichlorophosphate T=110°C; Vilsmeier reaction; 24 h;

1: 71 percent / K2CO3; Cu powder / nitrobenzene / 10 h / Heating 2: 42 percent / POCl3 / 24 h / 110 °C View Scheme

1: 71 percent / K2CO3; Cu powder / nitrobenzene / 10 h / Heating 2: 42 percent / POCl3 / 24 h / 110 °C View Scheme