[CH3:1][N:2]1[C:6]([CH3:7])=[C:5]([C:8](=O)[CH3:9])[CH:4]=[N:3]1.[C:11]1([C@H:17]([NH2:19])[CH3:18])[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1.C(O)C.[BH4-].[Na+]>CC(C)[O-].CC(C)[O-].CC(C)[O-].CC(C)[O-].[Ti+4].C1COCC1>[CH3:1][N:2]1[C:6]([CH3:7])=[C:5]([C@H:8]([NH:19][C@@H:17]([C:11]2[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=2)[CH3:18])[CH3:9])[CH:4]=[N:3]1
1-(1,5-Dimethyl-1H-pyrazol-4-yl)ethanone (J. Heterocyclic Chem. 1986, 23, 275-279, 4.82 g, 34.9 mmol) and (R)-1-Phenylethylamine (5.07 g, 41.9 mmol) in Titanium tetraisopropoxide (22.1 g, 77.7 mmol) were stirred at room temperature for 16 hours. Ethanol (30 ml) and THF (30 ml) were added at −20° C., then Sodium borohydride (3.96 g, 105 mmol) was added at −20° C. then the whole mixture was stirred for 3 h whilst warming to room temperature. The reaction was quenched with water (20 ml) and diluted with ethyl acetate-THF. Then the mixture was filtered through celite and washed with ethyl acetate. The filtrate was dried over Na2SO4, concentrated and purified by silica gel column chromatography eluted with ethyl acetate/n-Hexane=2/1 to 100/0 to furnish the title compound (3.44 g, 41% yield) as colorless oil. 1H NMR (270 MHz, CDCl3) δ 1.26 (3H, d, J=6.6 Hz), 1.27 (3H, d, J=6.6 Hz), 1.96 (3H, s), 3.44 (1H, q, J=6.6 Hz), 3.60 (1H, q, J=6.6 Hz), 3.76 (3H, s), 7.20-7.38 (6H, m).
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