反应详情

To a stirred suspension of 2-ethoxy-2-oxo-1-((1R,5R)-2-oxobicyclo[3.1.0]hexan-3-ylidene)ethanolate (300 mg, 1.28 mmol) in ethanol (5 mL) was added 2-hydrazinylpyrazine (141 mg, 1.28 mmol) followed by 6 N HCl (0.5 mL, 3.0 mmol). The reaction was stirred overnight at room temperature. The reaction was diluted with H2O and extracted with DCM. The combined organic phases were washed with H2O, dried over MgSO4, and concentrated. Purification by silica gel flash chromatography gave the title compound (150 mg). LCMS m/z=271.2 [M+H]+; 1H NMR (400 MHz, CDCl3) δ ppm 0.47 (td, J=4.7 and 3.4 Hz, 1H), 1.22-1.28 (m, 1H), 1.39 (t, J=7.1 Hz, 3H), 2.26-2.30 (m, 1H), 2.77-2.82 (m, 1H), 2.87 (d, J=16.6 Hz, 1H), 2.98 (dd, J=16.6 and 6.3 Hz, 1H), 4.40 (q, J=7.1 Hz, 2H), 8.40 (dd, J=2.6 and 1.5 Hz, 1H), 8.51 (d, J=2.5 Hz, 1H), 9.39 (d, J=1.3 Hz, 1H).

1. extractionextracted with DCM
2. washThe combined organic phases were washed with H2O
3. dry with materialdried over MgSO4
4. concentrationconcentrated
5. customPurification by silica gel flash chromatography