To 11H-benzo[a]carbazole (1.06 g, 3.23 mmol) in CH2Cl2 (5 ml) are added AlCl3 (0.510 g, 3.82 mmol) and 2,4,6-trimethylbenzoyl chloride (0.59 g, 3.24 mmol) at 0° C. After stirring at room temperature for 1 hour, AlCl3 (0.51 g, 3.82 mmol) and phenylacetyl chloride (0.52 g, 3.39 mmol) are added at 0° C. The reaction mixture is stirred at room temperature for 2 hours, and then it is poured into ice-water. The crude product is extracted with CH2Cl2, and washed with water and brine. After drying over MgSO4 and concentration, the product is reprecipitated from CH2Cl2 and n-hexane to obtain a white powder (1.53 g, 81%). The structure is confirmed by 1H-NMR spectrum (CDCl3). δ [ppm]: 0.79-0.91 (m), 1.18-1.50 (m), 2.19 (s), 2.28 (m), 2.41 (s), 4.38 (s), 4.74 (m), 6.97 (s), 7.22-7.36 (m), 7.56 (d), 7.71 (t), 7.77 (t), 8.14 (d), 8.35 (s), 8.62 (d), 8.63 (s), 9.58 (s).
