Diversification of Carbazoles by LiCl-mediated Catalytic CuI Reaction

Carbazole‐Terpyridine Donor‐Acceptor Dyads with Rigid π‐Conjugated Bridges

“…The residue was purified by silica gel column chromatography using hexane as eluent, to give product 12 as a pale‐yellow solid in 71 % yield (272.9 mg). Spectral data were consistent with the literature . In a Schlenk flask, 13 (132.2 mg, 1.02 mmol), Pd(PPh 3 ) 2 Cl 2 (59.4 mg, 0.08 mmol) and CuI (16.2 mg, 0.08 mmol) were added to a solution of 12 (272.9 mg, 0.85 mmol) in TEA (7 mL) and toluene (1 mL); the solution was then stirred under nitrogen atmosphere for 24 hours at 50 °C.…”

“…Compound 4 is prepared through a selective Ullman‐type condensation of p ‐iodo‐bromobenzene 11 with 9 H ‐carbazole promoted by Cu(I), which gives 12 in 71 % yield (Scheme ). This intermediate is then reacted with p ‐ethynyl benzaldehyde 13 in a palladium‐catalysed Sonogashira coupling, affording the aldehyde 14 in 22 % yield, which is finally condensed with 2‐acetylpyridine to form the terpyridine moiety and give compound 4 in 35 % yield.…”

“…9-(4-Bromophenyl)-9H-carbazole (12) was prepared according to a modification of a reported method. [50] Carbazole (200 mg, 1.2 mmol), Cs 2 CO 3 (325.8 mg, 1.2 mmol), CuI (22.8 mg, 0.12 mmol) and LiCl (50.7 mg, 1.2 mmol) were added to a solution of 1-bromo-4-iodobenzene (11) (372 mg, 1.32 mmol) in DMF (7 mL), and the resulting mixture was stirred at 150°C for 48 hours. Eventually, water was added and the mixture was extracted with ethyl acetate (5 × 10 mL).…”

“…Spectral data were consistent with the literature. [50] In a Schlenk flask, 13 (132.2 mg, 1.02 mmol), Pd(PPh 3 ) 2 Cl 2 (59.4 mg, 0.08 mmol) and CuI (16.2 mg, 0.08 mmol) were added to a solution of 12 (272.9 mg, 0.85 mmol) in TEA (7 mL) and toluene (1 mL); the solution was then stirred under nitrogen atmosphere for 24 hours at 50°C. The progress of the reaction was monitored using TLC analysis on silica gel petroleum ether/dichloromethane (2 : 1).…”

“…Synthesis of 9‐(4‐((4‐([2,2′:6′,2′′‐terpyridin]‐4′‐yl)phenyl)ethynyl) phenyl)‐9 H ‐carbazole ( 4 ). 9‐(4‐Bromophenyl)‐9 H ‐carbazole ( 12 ) was prepared according to a modification of a reported method . Carbazole (200 mg, 1.2 mmol), Cs 2 CO 3 (325.8 mg, 1.2 mmol), CuI (22.8 mg, 0.12 mmol) and LiCl (50.7 mg, 1.2 mmol) were added to a solution of 1‐bromo‐4‐iodobenzene ( 11 ) (372 mg, 1.32 mmol) in DMF (7 mL), and the resulting mixture was stirred at 150 °C for 48 hours.…”