2-(Di-tert-butylphosphino)biphenyl → 2-(9-(pyridin-2-yl)-9H-2,9'-bicarbazol-2'-yl)benzo[d]oxazole

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a dry Schlenk tube equipped with a magnetic stir bar was added 2-(9H-carbazol-2-yl)benzo[d]oxazole (569 mg, 2.0 mmol, 1.0 eq), 2-bromo-9-(pyridin-2-yl)-9H-carbazole (711 mg, 2.2 mmol, 1.1 eq), Pd2(dba)3 (37 mg, 0.04 mmol, 0.02 eq), JohnPhos (24 mg, 0.04 mmol, 0.04 eq) and tBuONa (308 mg, 3.2 mmol, 1.6 eq). The tube was evacuated and back-filled with nitrogen, and this evacuation/back-fill procedure was repeated twice. Then dry toluene (16 mL) was added under the atmosphere of nitrogen, the tube was then sealed quickly. The mixture was stirred in an oil bath at a temperature of 100-105° C. The reaction was monitored by TLC. 24 hours later, some starting material was not consumed. So more Pd2(dba)3 (37 mg, 0.04 mmol, 0.02 eq), SPhos (33 mg, 0.08 mmol, 0.04 eq) and tBuONa (96 mg, 1.0 mmol, 0.5 eq) and dioxane (3 mL) were added. The mixture was stirred in an oil bath at a temperature of 105-105° C. for another 24 hours and cooled to ambient temperature. The mixture was concentrated and the residue was purified through column chromatography on silica gel using dichloromethane/methanol (10:1) as an eluent to obtain the desired product, 2-(9-(pyridin-2-yl)-9H-2,9′-bicarbazol-2′-yl)benzo[d]oxazole Ligand N13N, as a brown solid (1056 mg in 99% yield). 1H NMR (DMSO-d6, 400 MHz): δ 7.37-7.50 (m, 6H), 7.52-7.61 (m, 2H), 7.66 (dd, J=8.0, 1.6 Hz, 1H), 7.75-7.78 (m, 2H), 7.91 (d, J=8.4 Hz, 2H), 8.06-8.11 (m, 2H), 8.17-8.19 (m, 2H), 8.40 (d, J=7.6 Hz, 1H), 8.45 (d, J=7.6 Hz, 1H), 8.52 (d, J=7.2 Hz, 1H), 8.64 (d, J=8.4 Hz, 1H), 8.67-8.68 (m, 1H).

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