反应详情

Trifluoro-methanesulfonic acid 2-(cyclopent-3-enecarbonyl)-4-methoxy-phenyl ester (19.09 g, 54.5 mmol) was dissolved in DMF (100 mL) under a N2 atmosphere and treated with diisopropylethylamine (10.6 g, 82.0 mmol), potassium acetate (1.07 g, 11.0 mmol) and 1,3-bis(diphenylphosphino)propane (2.25 g, 5.46 mmol). This mixture was stirred and degassed (3 vacuum/N2 purge cycles) then treated with palladium acetate (0.49 g, 2.18 mmol). After stirring 20 min. the mixture was warned to 120° C. for 18 hours, cooled and poured into brine (300 mL). The resulting mixture was extracted with EtOAc (4×100 mL) and the combined organic layer was washed with a sat. aq. NaHCO3 soln. (100 mL), H2O (100 mL), brine (100 mL), dried (MgSO4), filtered, concentrated and chromatographed on silica gel to provide an oil (10.4 g, 95%). (elute w/7% EtOAc/hexanes). 1H NMR (CDCl3) δ 7.41 (d, J=2.8 Hz, 1H), 7.03 (d, J=8.0 Hz, 1H), 6.88 (dd, J=8.0, 2.8 Hz, 1H), 6.72 (dd, J=5.2, 3.0 Hz, 1H), 6.06 (dd, J=5.2, 3.2 Hz, 1H), 3.77 (s, 3H), 3.60 (dd, J=4.3, 3.2 Hz, 1H), 3.44 (dd, J=5.0, 3.4 Hz, 1H), 2.65 (AB m, 1H), 2.56 (br AB d, J=10.5 Hz, 1H). 13C NMR (CDCl3) 196.11, 158.87, 145.90, 140.34, 130.295, 129.94, 126.14, 119.42, 111.90, 55.61, 55.48, 49.08, 45.97. GCMS m/e 200 (M+).

1. customdegassed
2. custom(3 vacuum/N2 purge cycles)
3. stirringAfter stirring 20 min. the mixture
4. temperaturecooled
5. extractionThe resulting mixture was extracted with EtOAc (4×100 mL)
6. washthe combined organic layer was washed with a sat. aq. NaHCO3 soln
7. dry with material(100 mL), H2O (100 mL), brine (100 mL), dried (MgSO4)
8. filtrationfiltered
9. concentrationconcentrated
10. customchromatographed on silica gel