Water → 4-Methylbiphenyl

Participants

Reaction Steps

In the drybox, 1100 mg (6.09 mm) of (Me3C)2P—Cl, 670 mg (2.98 mmol) of Pd(OAc)2 and 100 mL of 1,4-dioxane were loaded into a round-bottomed flask (250 mL) equipped with a magnetic stir bar. The resulting mixture was stirred at room temperature for 10 min before the flask was removed from the glove box. The mixture was refluxed under open-to-air condition. The progress of the reaction was monitored by phosphorus-31 NMR spectroscopy. After 2 h, approximately 95% of the reaction had proceeded. The phosphorus-31 NMR spectrum of the reaction mixture showed only the δ123.0 (singlet) resonance, and no unchanged (Me3C)2P—Cl. The reaction mixture was therefore cooled to room temperature and 600 mg (33.3 mmol) of H2O was added. The mixture above was refluxed for a further 15 min. Next, 12.659 g (100.0 mm) of 4-chlorotoluene, 13.41 g (110.0 mm) of PhB(OH)2 and 22.785 g (150.0 mm) of CsF were added into the mixture above. The resulting mixture was refluxed for 18 h. The reaction mixture was then cooled to room temperature, quenched with 200 mL of H2O, and extracted with diethyl ether (2×300 mL). The organic extracts were washed with H2O (2×250 mL), brine (250 mL), and dried over mgSO4, filtered, and the ether and dioxane removed from the filtrate by rotary evaporation. The resulting residue was chromatographed on silicon gel using hexane as eluant. The eluate was concentrated by rotary evaporation followed by high vacuum to yield 4-phenyltoluene.

Provenance & Evidence