反应详情

Pd(PPh3)4 (196 mg, 0.17 mmol) was added to a stirred solution of chloride 27 (329 mg, 1.7 mmol) and tetraethyltin (0.7 mL, 3.3 mmol) in DME (20 mL), the solution degassed, and stirred under N2 at reflux temperature for 16 h. The solvent was evaporated and the residue purified by chromatography, eluting with 20% EtOAc/pet. ether to give an oil which was further purified by chromatography, eluting with 5% EtOAc/DCM, to give 1-oxide 28 (295 mg, 93%) as a white solid, mp (EtOAc/pet. ether) 122-124° C.; 1H NMR δ 8.48 (dd, J=9.5, 5.5 Hz, 1 H, H-8), 7.60 (dd, J=8.7, 2.6 Hz, 1 H, H-5), 7.38 (m, 1 H, H-7), 3.04 (q, J=7.6 Hz, 2 H, CH2), 1.43 (t, J=7.6 Hz, 3 H, CH3); 13C NMR δ 168.6 (q, J=175 Hz), 165.1, 149.5(d, J=15 Hz), 130.5, 123.2 (d, J=11 Hz), 120.0 (d, J=26 Hz), 112.7 (d, J=22 Hz), 30.7, 12.2. Anal. Calcd for C9H8FN3O: C, 56.0; H, 4.2; N, 21.8. Found: C, 56.0; H, 4.2; N, 21.8%.

1. customthe solution degassed
2. temperatureat reflux temperature for 16 h
3. customThe solvent was evaporated
4. customthe residue purified by chromatography
5. washeluting with 20% EtOAc/pet. ether
6. customto give an oil which
7. customwas further purified by chromatography
8. washeluting with 5% EtOAc/DCM