Into a flask containing a solution of (S)-4-(1-(2-aminopropyl)-1H-pyrazol-3-yl)-2-chlorobenzonitrile (0.4 g, 17.5 mmol) in toluene (20 ml), 2 M solution of trimethyl aluminium in heptane (2.62 ml, 52.6 mmol) was added at 0° C. The resulting mixture was stirred at 0° C. for 10 min and a solution of methyl 2-((tert-butyldimethyl-silyloxy)methyl)-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-imidazole-4-carboxylate (0.7 g, 17.5 mmol) in toluene (20 ml) was added at 0° C. The reaction mixture was heated at 110° C. for 4 h and diluted with water. The mixture was filtered through a celite bed and the filtrate was extracted with EtOAc. The organic layer was concentrated under reduced pressure. The product was purified by flash column chromatography. Yield 400 mg. 1H-NMR (400 MHz; DMSO-d6): δ −0.05 (s, 9H), 0.05 (s, 6H), 0.82-0.84 (s, 11H), 1.14 (d, 3H), 3.47 (t, 2H), 4.26-4.40 (m, 3H), 4.74 (s, 2H), 5.38 (s, 2H), 6.94 (d, 1H), 7.73 (s, 1H), 7.83 (d, 1H), 7.99 (d, 2H), 8.10 (d, 2H). LC-MS: [M+1]=629.38.
