反应详情

To a stirred solution of (2-chloro-5-iodo-pyridin-4-yl)-methanol (2 g, 7.44 mmol, 1 eq) in dry THF (20 mL) was added i-PrMgCl.LiCl complex (1.3M in THF, 13.7 mL, 17.8 mmol, 2.4 eq) at −20° C. in drop wise manner over period of 10 minutes. Pre-dissolved solution of N-boc-3-azetidinone (1.53 g, 8.9 mmol, 1.2 eq) in dry THF (10 mL) was added at −20° C. to above reaction mixture. Resulting reaction mixture was stirred at room temperature for 16 hours under nitrogen atmosphere. After maximum consumption of starting material, reaction mixture was cooled to 0° C., quenched with 10% citric acid solution (20 mL) and extracted with ethyl acetate (3×50 mL). Combined organic phase was dried over anhydrous Na2SO4 and concentrated under reduced pressure to get brown oil (2.2 g, crude). Crude compound was purified by column chromatography by using silica gel (100-200 mesh). Desired compound was eluted at 20% ethyl acetate in hexane to afford title compound as yellow solid (0.45 g, 19%). 1H NMR (400 MHz, CDCl3) δ: 1.38 (s, 9H), 3.96 (d, J=8.8 Hz, 2H), 4.38 (d, J=9.32 Hz, 2H), 4.53 (d, J=5.64 Hz, 2H), 5.53 (t, J=5.32 Hz, 1H), 6.40 (s, 1H), 7.57 (s, 1H), 8.33 (s, 1H). LC-MS (m/z): 314.9 (M+H).

1. customResulting
2. customreaction mixture
3. customAfter maximum consumption of starting material, reaction mixture
4. temperaturewas cooled to 0° C.
5. customquenched with 10% citric acid solution (20 mL)
6. extractionextracted with ethyl acetate (3×50 mL)
7. dry with materialCombined organic phase was dried over anhydrous Na2SO4
8. concentrationconcentrated under reduced pressure
9. customto get brown oil (2.2 g, crude)
10. customCrude compound was purified by column chromatography
11. washDesired compound was eluted at 20% ethyl acetate in hexane