反应详情

To a stirred solution of indole 1 (Example 11, Step 3; 480 mg, 1.01 mmol) in DMF (10 mL) under inert atmosphere were added Cs2CO3 (1.32 g, 4.05 mmol) and 2-bromoethan-1-ol (152 mg, 1.27 mmol) at RT and stirred for 16 h. The mixture was diluted with water (20 mL) and extracted with EtOAc (3×20 mL). The combined organic extracts were dried (Na2SO4), filtered and concentrated under reduced pressure to obtain the crude. This was purified (silica gel; 55% EtOAc/hexanes) to obtain compound 2 (100 mg, 19%) as a colorless syrup. 1H NMR (400 MHz, CDCl3): δ 7.72 (d, J=6.8 Hz, 2H), 7.62 (dt, J=8.0 Hz, 1.6 Hz, 1H), 7.18 (d, J=8.4 Hz, 1H), 7.10-7.07 (m, 1H), 6.94 (t, J=8.0 Hz, 1H), 6.78 (dt, J=8.0, 1.6 Hz, 1H), 4.41 (q, 2H), 4.36-4.34 (m, 2H), 4.10 (t, J=4.8 Hz, 2H), 2.72 (br s, 1H), 1.74-1.67 (m, 1H), 1.41 (t, J=7.2 Hz, 3H), 1.08-1.04 (m, 2H), 0.90-0.85 (m, 2H); LC-MS: m/z 518.7 (M+H+).

1. extractionextracted with EtOAc (3×20 mL)
2. dry with materialThe combined organic extracts were dried (Na2SO4)
3. filtrationfiltered
4. concentrationconcentrated under reduced pressure
5. customto obtain the crude
6. customThis was purified (silica gel; 55% EtOAc/hexanes)