N-(2-chloroethyl)benzamide (6.3 g, 34 mmol) and PCl5 (7.9 g, 38 mmol) were suspended in xylene (75 mL) and refluxed for two hours. Then 1,3-diisopropyldibenzo[b,d]furan-4-amine (10 g, 38 mmol) was added. The mixture was refluxed overnight. After cooling by ice-bath, no precipitation was observed. The mixture was concentrated and the residue was washed with small amount of toluene and hexane. The crude 1-(1,3-diisopropyldibenzo[b,d]furan-4-yl)-2-phenyl-4,5-dihydro-1H-imidazole (7.5 g, 19 mmol, 54.8% yield) was used without further purification for the next step.
