[CH3:1][O:2][C:3]1[CH:4]=[C:5]([CH:10]=[CH:11][C:12]=1[O:13][CH3:14])[CH:6]=[CH:7][C:8]#[N:9]>CCO.Cl.[Pd]>[CH3:1][O:2][C:3]1[CH:4]=[C:5]([CH2:6][CH2:7][CH2:8][NH2:9])[CH:10]=[CH:11][C:12]=1[O:13][CH3:14]3,4-Dimethoxycinnamonitrile (5 g) was dissolved in a mixture of EtOH (100 mL) and conc. HCl (10 mL) and hydrogenated with 10% Pd/C (wet, Degussa Type E101, Aldrich) at 65 psi on a Pan shaker for 70 h. The reaction mixture was filtered over Celite and the filtrate was concentrated to remove most of the EtOH. The residue was extracted twice with Et2O (discarded) and then cooled with ice and made strongly basic with 10 M aq. NaOH solution. The basic aqueous layer was extracted with Et2O and the organic layer was dried over anhydrous sodium sulfate and concentrated under reduced pressure to give 3-(3,4-dimethoxyphenyl)propylamine (5.07 g) as a pale yellow oil. 1H-NMR (300 MHz, CDCl3): δ=6.68-6.78 (m, 3H), 3.83 (s, 3H, OMe), 3.82 (s, 3H, OMe), 2.70 (t, J=7.0 Hz, 2H), 2.58 (t, J=7.2 Hz, 2H), 1.70-1.75 (m, 2H), 1.17 (broad s, 2H, NH2).
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