[Cl:1][C:2]1[CH:3]=[C:4]([C@H:8]([NH2:10])[CH3:9])[CH:5]=[CH:6][CH:7]=1.[Br:11][C:12]1[CH:13]=[C:14]([C:19](=O)[CH3:20])[CH:15]=[CH:16][C:17]=1[Cl:18].C(N(CC)CC)C.C([BH3-])#N.[Na+]>COCCOC.CO.[Ti](Cl)(Cl)(Cl)Cl>[Br:11][C:12]1[CH:13]=[C:14]([CH:19]([NH:10][C@@H:8]([C:4]2[CH:5]=[CH:6][CH:7]=[C:2]([Cl:1])[CH:3]=2)[CH3:9])[CH3:20])[CH:15]=[CH:16][C:17]=1[Cl:18]
A solution of (R)-1-(3-chlorophenyl)ethanamine 107 (0.701 g, 4.50 mmol), 1-(3-bromo-4-chlorophenyl)ethanone 106 (1.00 g, 4.29 mmol), and triethylamine (1.79 mL, 12.9 mmol) in dry DME was chilled to −78° C. in a dry ice bath. Via syringe, titanium(IV) chloride (4.50 mL, 4.50 mmol) was added dropwise to the reaction mixture. The reaction was warmed to ambient temperature and it was stirred under N2 for 10 h. A solution of sodium cyanoborohydride (0.674 g, 10.7 mmol) in 4 mL of MeOH was then added slowly to the reaction mixture and the reaction solution was stirred for another 3 h. The reaction was quenched by the addition of saturated NH4Cl. The solution was diluted with ether and water, and the mixture was extracted with water (2×) and brine. The organic layer was dried over MgSO4, filtered, and concentrated in vacuo. The crude material was purified by silica gel chromatography using a 3% to 30% gradient of EtOAc in hexanes as the eluent. The desired fractions were combined and concentrated to give 1-(3-bromo-4-chlorophenyl)-N—((R)-1-(3-chlorophenyl)ethyl)ethanamine 108 (1.04 g, 65.0% yield) as a colorless oil.
Loading…
