Bis(1,5-cyclooctadiene)nickel(0)

• 4'-Chloroacetophenone [C0033]
• Phenylboronic Acid [B0857]
• Bis(1,5-cyclooctadiene)nickel(0) (= Ni(cod)₂) [B6553]
• Triphenylphosphine [T0519]
• Tripotassium Phosphate　
• THF

Phenylboronic acid (366 mg, 3.0 mmol, 1.5 eq.), triphenylphosphine (42 mg, 0.16 mmol, 0.08 eq.), tripotassium phosphate (1.27 g, 6.0 mmol, 3.0 eq.) and Ni(cod)₂ (22 mg, 0.08 mmol, 0.04 eq.) were weighed and sealed in a glove box. To this mixture, 4’-chloroacetophenone (0.26 mL, 2.0 mmol) in THF (8 mL) was added and the reaction mixture was stirred for 24 hours at r.t., and then quenched with water (15 mL). The solution was extracted with ethyl acetate (15 mL x 3) and the combined organic layer was washed with brine (15 mL), dried over sodium sulfate and filtered. The solvent was removed under reduced pressure and the residue was purified by column chromatography (on silica gel, ethyl acetate:hexane = 1:10) to give 4-acetylbiphenyl as a white solid (360 mg, 92% yield).

The reaction mixture was monitored by GC.
Commercially available dry THF was used.
The functionality of the partially discolored Ni(cod)₂ was verified, and it was confirmed through this experiment that the reaction proceeded without any problems.

4-Acetylbiphenyl

¹H NMR (400 MHz, CDCl₃); δ 8.04 (d, J = 8.0 Hz, 2H), 7.69 (d, J = 8.0 Hz, 2H), 7.63 (d, J = 7.2 Hz, 2H), 7.50-7.46 (m, 2H), 7.42-7.39 (m, 1H), 2.65 (s, 3H).

• Triphenylphosphine as a Ligand for Room-Temperature Ni(0)-Catalyzed Cross-Coupling Reactions of Aryl Chlorides with Arylboronic Acids
• Z.-Y. Tang, Q.-S. Hu, J. Org. Chem. 2006, 71, 2167.