反应详情

A solution of compound 1 (2.0 g, 16.78 mmol) and compound 2 (3.15 g, 20.139 mmol) in dry methanol (20 mL) was treated with acetic acid (2.4 mL, 42.00 mmol) followed by NaCNBH3 (1.26 g, 20.14 mmol) at 0° C. The resulting mixture was brought to room temperature and stirred for 3 h. The reaction was basified with 1 N NaOH solution (50 mL) and product was extracted into ethyl acetate (2×50 mL). The combined ethyl acetate layer was washed with brine (25 mL) and dried (Na2SO4). The solvent was evaporated and the crude product was purified by column chromatography (ethyl acetate:hexanes, 1:4) to obtain compound 3 (3.52 g, 81%) as a solid. 1H NMR (CDCl3) δ 7.06-7.02 (m, 2H), 6.59 (t, J=14.7 Hz, 1H), 6.42 (d, J=8.1 Hz, 1H), 3.46 (s, 4H), 3.46-3.35 (m, 3H), 2.93 (t, J=16.5 Hz, 2H), 1.87-1.60 (m, 8H). MS-ESI (m/z, %): 262 (8), 260 (MH+, 100), 120 (28).

1. customwas brought to room temperature
2. extractionwas extracted into ethyl acetate (2×50 mL)
3. washThe combined ethyl acetate layer was washed with brine (25 mL)
4. dry with materialdried (Na2SO4)
5. customThe solvent was evaporated
6. customthe crude product was purified by column chromatography (ethyl acetate:hexanes, 1:4)