Short-RInChIKey=SA-FUHFF-UHFFFADPSC-OYFFSPILVQ-UHFFFADPSC-NUHFF-NUHFF-NUHFF-ZZZ

9H-Carbazole (500 mg, 2.99 mmol, 1.00 equiv) and zinc dichloride (856 mg, 6.28 mmol, 2.10 equiv) were dried in a vial. Nitromethane (10 mL) was added under argon atmosphere. A solution of 2-chloro-2-methylpropane (581 mg, 687 μL, 6.15 mmol, 2.06 equiv) in nitromethane (5 mL) was added dropwise. The reaction was stirred at 25 °C for 22 h. The reaction was then pourred in water (40 mL) and extracted with ethyl acetate (3 x 30 mL). The organic layers were collected and dried over Na2SO4. The solvent was removed under reduced pressure. The obtained crude product was purified via flash-chromatography (Interchim PuriFLASH XS 420) on silica gel (PF-15SIHP-F0040, 15 μm) using cyclohexane/ethyl acetate 100:0 to 98:2 within 15 column volumes (1 column volume = 91.9 mL; flowrate = 26 mL/min). 3,6-Ditert-butyl-9H-carbazole was isolated as a yellow solid in 77% (645 mg, 2.31 mmol).