[1,3-Bis(2,6-Diisopropylphenyl)imidazol-2-ylidene](3-chloropyridyl)palladium(II) Dichloride

Used Chemicals

• 9-[4-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-9H-carbazole [T3452]
• 2-([1,1'-Biphenyl]-3-yl)-4-chloro-6-phenyl-1,3,5-triazine [B5803]
• [1,3-Bis(2,6-Diisopropylphenyl)imidazol-2-ylidene](3-chloropyridyl)palladium(II) Dichloride (= Organ’s catalyst) [B6199]
• Potassium Carbonate [P1748]
• THF
• Water

Procedure

To a 100 mL 4-neck flask under nitrogen atmosphere, 2-([1,1'-biphenyl]-3-yl)-4-chloro-6-phenyl-1,3,5-triazine (1.10 g, 3.20 mmol), 4-(9H-carbazol-9-yl)phenylboronic acid pinacol ester (1.42 g, 3.85 mmol, 1.2 eq), potassium carbonate (0.89 g, 6.40 mmol), THF (20 mL), water (8 mL) and Organ’s catalyst (2.2 mg, 3.2 µmol, 0.1 mol%) were added, and the reaction mixture was refluxed for 1 hour. After confirming the disappearance of the raw material, the reaction mixture was cooled to room temperature, and then water (20 mL) was added and the precipitated solid was filtered out. The obtained crude product was filtered through a short pad of silica gel using CH₂Cl₂ as eluent and the filtrate was evaporated in vacuo to give a white solid. The solid was washed with methanol to give 1 (1.70 g, 96% yield) as a white powder.

Experimenter’s Comments

The reaction mixture was monitored by TLC (ethyl acetate:hexane = 1:10, Rf = 0.53).

Analytical Data

Compound 1

¹H NMR (400 MHz, CDCl₃); δ 9.05–9.02 (m, 3H), 8.85–8.80 (m, 3H), 8.18 (d, 2H, J = 7.6 Hz), 7.88–7.82 (m, 3H), 7.77 (d, 2H, J = 6.8 Hz), 7.70-7.52 (m, 8H), 7.49-7.42(m, 3H), 7.34 (t, 2H, J = 7.6 Hz).

¹³C NMR (101 MHz, CDCl₃); δ 171.8, 171.7, 170.9, 141.8, 141.6, 140.8, 140.4, 136.6, 136.1, 134.8, 132.7, 131.4, 130.6, 129.1, 129.0, 128.9, 128.7, 127.9, 127.7, 127.6, 127.3, 126.6, 126.1, 123.7, 120.4, 109.9

Lead Reference

• Easily Prepared Air- and Moisture-Stable Pd–NHC (NHC=N-Heterocyclic Carbene) Complexes: A Reliable, User-Friendly, Highly Active Palladium Precatalyst for the Suzuki–Miyaura Reaction
• C. J. O'Brien, E. A. B. Kantchev, C. Valente, N. Hadei, G. A. Chass, A. Lough, A. C. Hopkinson, M. G. Organ, Chem. Eur. J. 2006, 12, 4743.

References

• Pd-Catalyzed Aryl Amination Mediated by Well Defined, N-Heterocyclic Carbene (NHC)–Pd Precatalysts, PEPPSI
• M. G. Organ, M. Abdel-Hadi, S. Avola, I. Dubovyk, N. Hadei, E. A. B. Kantchev, C. J. O'Brien, M. Sayah, C. Valente, Chem. Eur. J. 2008, 14, 2443.