反应详情

A mixture of N-(4,4-dimethyl-chroman-7-yl)-acetamide (1.35 g, 6.2 mmol) in 20% HCl solution (30 mL) was heated at reflux for 3 h and then cooled to room temperature. The reaction mixture was basified with 10% aq. NaOH to pH 8 and extracted with EtOAc (30×3 mL). The combined organic layers were washed with brine, dried over anhydrous Na2SO4 and concentrated to give 3,4-dihydro-4,4-dimethyl-2H-chromen-7-amine (C-5) (1 g, 92%). 1H NMR (DMSO-d6) δ 6.87 (d, J=8.4 Hz, 1 H), 6.07 (dd, J=8.4, 2.4 Hz, 1 H), 5.87 (d, J=2.4 Hz, 1 H), 4.75 (s, 2 H), 3.99 (t, J=5.4 Hz, 2 H), 1.64 (t, J=5.1 Hz, 2 H), 1.15 (s, 6 H); ESI-MS 178.1 m/z (MH+).

1. temperaturewas heated
2. temperatureat reflux for 3 h
3. extractionextracted with EtOAc (30×3 mL)
4. washThe combined organic layers were washed with brine
5. dry with materialdried over anhydrous Na2SO4
6. concentrationconcentrated