Under argon protection, N-(2-chlorophenyl)-9,9-dimethyl-9H-fluoren-2-amine (46.7 g, 14.6 mmol), Pd(OAc)2 (1.64 g, 7.32 mmol), HBF4 (3.62 g, 14.6 mmol), K2CO3 (60.5 g, 438 mmol) and dimethylformamide (50 mL) were were added to the reaction flask. The reaction mixture was stirred at 200°C for 12 hours. After completion of the reaction, the mixture was extracted with ethyl acetate. The organic layers were combined, dried with anhydrous MgSO4, filtered and the organic phase was concentrated. Purification by column chromatography afforded the target product 5,7-dihydro-7,7-dimethylindeno[2,1-b]carbazole (35.17 g, 85% yield).
![5,7-Dihydro-7,7-dimethyl-indeno[2,1-b]carbazole](/CAS/GIF/1257220-47-5.gif)