反应详情

Oxalyl chloride (0.08 mL, 114 mg, 0.9 mmol) was added dropwise to a stirred, cooled (0° C.) solution of 5-chloro-2-(4-chlorophenyl)-1-methyl-1H-indole-3-propanoic acid (Description 12, 330 mg, 0.95 mmol) and DMF (1 drop) in toluene (15 mL) and the mixture was stirred at room temperature for 2 h. to give a solution of 5-chloro-2-(4-chlorophenyl)-1-methyl-1H-indole-3-propanoyl chloride. A sample (7.5 mL) was added to a solution of 1-(phenylmethyl)piperazinone (Tet.Lett. 1996, 37, 7339-7342) (90 mg, 0.48 mmol) and triethylamine (0.1 mL, 73 mg, 0.72 mmol) in THF (5 mL) and the mixture was stirred at room temperature. Water was added and the mixture was extracted with ethyl acetate. The combined organic fractions were dried (MgSO4) and the solvent was evaporated under reduced pressure. The residue was purified by flash column chromatography on silica gel, eluting with hexane/EtOAc (80:20) to give the title compound as a colorless foam. 1H NMR (360 MHz, CDCl3) mixture of two amide rotamers; major isomer, δ7.57-7.18 (12H, m), 4.38 (2H, s), 3.86 (2H, s), 3.63 (2H, t, J 5.3 Hz), 3.55 (3H, s), 3.08-2.96 (4H, m), and 2.43 (2H, t, J 7.4 Hz); minor isomer, δ7.57-7.18 (12H, m), 4.57 (2H, s), 4.26 (2H, s), 3.50 (3H, s), 3.37 (2H, t, J 5.3 Hz), 3.08-2.96 (4H, m), and 2.48 (2H, t, J 7.4 Hz). m/z (ES+) 520, 522 (M+1).