SIOC English
有机化学
高级检索

有机化学 ›› 2010, Vol. 30 ›› Issue (11): 1737-1741. 上一篇    下一篇

研究简报

7-O-取代-8-甲基香豆素和4H-色烯-4-酮化合物与NBS/CCl4试剂的溴化反应

成明，裘亚，刘红山，夏鹏，陈瑛*   

  1. (复旦大学药学院 上海 201203)
  • 收稿日期:2010-01-14 修回日期:2010-05-21 发布日期:2010-06-15
  • 通讯作者: 陈瑛 E-mail:yingchen71@fudan.edu.cn
  • 基金资助:

    国家自然科学基金

Bromination of 7-O-Substituted-8-methyl-coumarins and 4H-Chromen-4-ones with N-Bromosuccinimide in CCl4

CHENG Ming, QIU Ya, LIU Hong-Shan, XIA Peng, CHEN Ying   

  1. (School of Pharmacy, Fudan University, ShangHai 201203)
  • Received:2010-01-14 Revised:2010-05-21 Published:2010-06-15

PDF

1516

7-O-取代-8-甲基香豆素和4-H-色烯-4-酮化合物是合成Seco-DCK和Seco-DCP类似物的重要中间体. 报道了在NBS/CCl4条件下, 这两类化合物8-位甲基溴代反应的情况. 通过实验发现, 这两类化合物8-位甲基溴代反应较一般芳环苄位的溴代更为复杂, 存在多个反应位点. 影响8-位甲基溴代选择性和收率的主要因素有三: 邻位基团空间位阻大小、自由基引发催化剂的使用与否以及邻位基团的电性因素. 通过控制反应条件, 可以中等收率得到8-位甲基溴代化合物.

关键词: 7-O-取代-8-甲基取代香豆素, 7-O-取代-8-甲基-4-H-色烯-4-酮, Seco-DCK, Seco-DCP, 溴代

The bromination of 7-O-substituted-8-methyl-coumarins and 4H-chromen-4-ones, two key intermediates in the synthesis of Seco-DCK and Seco-DCP analogues, with N-bromosuccinimide in CCl4 is reported. The experimentation showed that the selectivity of bromination of 8-methyl is more complicated than that of common benzyls, due to the presence of multiple reactive sites in these two title substrates. Diversity of the products was discussed and the reasonable explanation for which was provided. The bulky group of 7-O-substitutes, its electric property as well as addition of free radical initiator could affect the selectivity and the yield of bromination of 8-methyl. The desired 8-bromomethyl products could be obtained in mild yields under optimized condition.

Key words: 7-O-substituted-8-methyl-coumarin, 7-O-substituted-8-methyl-4H-chromen-4-one, Seco-DCK, Seco-DCP, bromination