Diphenylmethanimine (7.53 g, 39.5 mmol), BINAP (447 mg, 0.718 mmol) and sodium tert-butoxide (6.9 g, 71.8 mmol) were dissolved in 100 ml of toluene. The reaction mixture was heated to 105° C. and stirred for 5 min. Then 3-(4-bromo-benzyl)-2-ethyl-5,7-dimethyl-pyrazolo[1,5-a]pyrimidine (3) (13 g, 35.9 mmol) and palladium diacetate (81 mg, 0.36 mmol) were added and the reaction mixture was stirred for 12 h at 110° C. The organic layer was extracted two times with EtOAc, washed with water and brine, dried over Na2 SO4 and concentrated under reduced pressure. The precipitate was suspended in cyclohexane and filtered to afford a beige solid.
