反应详情

A mixture of 131 (1.5 g, 11 mmol) and phosphorus oxychloride (9 mL, 0.1 mol) was heated at reflux for 6 h. The reaction mixture was cooled to room temperature, and the excess phosphorus oxychloride was removed under reduced pressure. Ice cold water (50 mL) was added to the residue. The brown precipitate was collected and washed with ice cold water (3×25 mL), ether (2×20 mL), and dried to provide 132 as a light-brown solid (0.9 g, 54%): mp 104-105° C. (lit. (Synthesis 1991, 894-896) mp 106-108° C.). 1HNMR (300 MHz, CDCl3) δ 7.83 (d, J=8.1 Hz, 1H), 7.29 (d, J=8.1 Hz, 1H), 2.77 (s, 3H).

1. temperaturewas heated
2. temperatureat reflux for 6 h
3. customthe excess phosphorus oxychloride was removed under reduced pressure
4. additionIce cold water (50 mL) was added to the residue
5. customThe brown precipitate was collected
6. washwashed with ice cold water (3×25 mL), ether (2×20 mL)
7. customdried