Bis(1,10-phenanthroline)palladium(II) Bis(hexafluorophosphate)

Experimental procedure²⁾: DMA (0.5 mol/L) is added to a vessel and degassed by a freeze－pump－thaw cycle (3 times). To this is added Pd(OAc)₂ (5 mol%), tri(2-furyl)phosphine (10 mol%), K₂CO₃ (1 eq.), 1-methylimidazole (1 mmol), and 4-bromobenzotrifluoride (1 eq.). The mixture is stirred for 4 h at 150 °C under an argon atmosphere. The reaction mixture is then cooled to room temperature. To this is added iodobenzene (1 eq.), Cs₂CO₃ (1 eq.), and [Pd(phen)₂](PF₆)₂ (5 mol%), and the mixture is stirred for 4 h at 150 °C under an argon atmosphere. Subsequently, 4-iodoanisole (3 eq.), Cs₂CO₃ (3 eq.), and [Pd(phen)₂](PF₆)₂ (15 mol%) are split into 6 portions, respectively, and added portionwise to the reaction mixture every 0.5 h at 150 °C. The resulting mixture is stirred at that temperature for 20 h under an argon atmosphere. The reaction mixture is filtered through a Celite pad and concentrated in vacuo. The residue is purified by flash column chromatography on silica gel (hexane:EtOAc = 10:1) to give 1 in 37% yield (151 mg).