To a solution of 2-(3-bromophenyl)-N-cyclopentyl-3-[2-(cyclopentylamino)-4-pyrimidinyl]pyrazolo[1,5-a]pyridin-7-amine (3.00 g, 5.8 mmol) in toluene (60 mL) was added benzophenone imine (3.15 g, 17.4 mmol), tris(dibenzylideneacetone)dipalladium (0.26 g, 0.3 mmol), rac-2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (0.54 g, 0.15 mmol) and sodium tert-butoxide (1.67 g, 17.4 mmol). The reaction was heated at reflux for 5 hours, then allowed to cool to room temperature. Water and ethyl acetate were added to the reaction mixture. The phases were separated and the organic phase was washed with brine and dried (magnesium sulfate). Filtration and concentration of the filtrate followed by purification with flash chromatography (4:6 ethyl acetate:hexanes) gave N-cyclopentyl-3-[2-(cyclopentylamino)-4-pyrimidinyl]-2-{3-[(diphenylmethylene)amino]phenyl}-pyrazolo[1,5-a]pyridin-7-amine (2.61 g, 73%) as a yellow solid. 1H NMR (CDCl3): δ 7.89 (d, 1H), 7.80–7.75 (m, 3H), 7.48 (m, 1H), 7.41 (m, 2H), 7.27 (m, 5H), 7.23–7.12 (m, 4H), 7.04 (s, 1H), 6.80 (d, 1H), 6.03–5.97 (m, 3H), 4.39 (m, 1H), 4.00 (m, 1H), 2.15–2.05 (m, 4H), 1.83–1.56 (m, 12H); MS m/z 618 (M+1).
