反应详情

A mixture of 101b (1000 g, crude) in thionyl chloride (1.5 L) was refluxed for 1 hour. The reaction mixture was cooled to room temperature and poured into 500 mL of stirred Et2O, during which time a white precipitate formed. The precipitate was collected by filtration and washed with Et2O, dissolved in 500 mL of water and neutralized with 25 percent NaOH. The yellow aqueous solution was extracted with EtOAC (3×500 mL) and the combined organic phase was washed with 500 mL of brine, dried over Na2SO4, filtered and concentrated in vacuo to provide 101c (530 g, 40.8% over 3 steps) as a white solid. 1HNMR (300 MHz, CDCl3) δ 7.87 (d, J=8.4 Hz, 2H), 7.41 (d, J=8.4 Hz, 2H), 4.08 (s, 2H), 1.37 (s, 6H), 1.33 (s, 9H).

1. temperaturewas refluxed for 1 hour
2. customformed
3. filtrationThe precipitate was collected by filtration
4. washwashed with Et2O
5. dissolutiondissolved in 500 mL of water and neutralized with 25 percent NaOH
6. extractionThe yellow aqueous solution was extracted with EtOAC (3×500 mL)
7. washthe combined organic phase was washed with 500 mL of brine
8. dry with materialdried over Na2SO4
9. filtrationfiltered
10. concentrationconcentrated in vacuo