“…The mixture was heated to reflux for 16 h, cooled to room temperature, and filtered through a pad of Celite which was washed well with ethyl acetate. The filtrate was concentrated in vacuo, and the residue was purified by flash column chromatography (SiO 2 , 1:1, hexane/ethyl acetate) to provide 19 as an orange solid (81 mg, 39%): 31 2,6-Bis[(4R,5R)-4,5-Dihydro-4,5-diphenyl-1H-imidazol-2-yl]pyridine (20). Cesium carbonate (85 mg, 0.26 mmol), anhydrous toluene (1 mL), 2,6-dibromopyridine (47.4 mg, 0.2 mmol), tert-butyl isocyanide (68 μL, 0.6 mmol), (1R,2R)-(+)-1,2-diphenylethylenediamine (425 mg, 2.0 mmol), palladium(II) chloride (1.8 mg, 0.01 mmol), and dppp (8.2 mg, 0.02 mmol) were added to an oven-dried, three-necked flask under nitrogen.…”