反应详情

To a solution of 2-phenylethylmagnesium chloride (1 M in THF, 3.0 mL, 3.00 mmol) in THF (5 mL) was added dropwise a solution of 3,4-dimethoxybenzonitrile (326 mg, 2.00 mmol) in THF (5 mL). After 23 h of reflux, dry methanol (2.5 mL) and a solution of (R)-2-amino-N-methyl-2-phenyl acetamide (accessable via: J. Org. Chem. 2005, 70, 10792-10802, 672 mg, 4.00 mmol) in dry methanol (2.5 mL) were added successively at 0° C. After stirring at ambient temperature for 1 h the reaction mixture was cooled to 0° C. and sodium borohydride (158 mg, 4.00 mmol) was added in small portions. After stirring for 5.5 h at ambient temperature, aqueous ammonium chloride (sat.) was added and extracted with tert-butylmethylether. The organic layers were combined, dried over sodium sulfate and concentrated. Purification by chromatography (SiO2, heptane:ethyl acetate:methanol=3:1:0 to 0:9:1) afforded the title compounds (R)-2-[(R)-1-(3,4-dimethoxy-phenyl)-3-phenyl-propylamino]-N-methyl-2-phenyl-acetamide (1st eluting compound, 175 mg, 21%) as a light yellow oil (MS: m/e=419.3 [M+H]+ and (R)-2-[(S)-1-(3,4-dimethoxy-phenyl)-3-phenyl-propylamino]-N-methyl-2-phenyl-acetamide (2nd eluting compound, 175 mg, 21%) as a light yellow oil (MS: m/e=419.3 [M+H]+.

1. temperatureAfter 23 h of reflux
2. temperaturewas cooled to 0° C.
3. stirringAfter stirring for 5.5 h at ambient temperature
4. extractionextracted with tert-butylmethylether
5. dry with materialdried over sodium sulfate
6. concentrationconcentrated
7. customPurification by chromatography (SiO2, heptane:ethyl acetate:methanol=3:1:0 to 0:9:1)