一个金属催化分子间 [5+2] 循环添加/纳扎罗夫循环化序列和级联
Paul A Wender1, René T Stemmler, Lauren E Sirois
1Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA. wenderp@stanford.edu
Journal of the American Chemical Society
|February 10, 2010
概括
研究人员开发了一种新的金属催化 [5+2] 乙烯基cyclopropanes (VCPs) 和enynones的循环添加. 这种高效的过程通过联合循环添加和纳扎罗夫循环反应,可以轻松进入bicyclo[5.3.0]decane骨架.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 合成方法论 合成方法论
背景情况:
- 双循环[5.3.0]十甲基骨架是自然产品和生物活性分子中普遍存在的结构图案.
- 有效的合成路线到这个核心支架对于药物发现和开发至关重要.
研究的目的:
- 报告第一个金属催化 [5+2] 乙烯基cyclopropanes (VCPs) 和enynones之间的循环添加反应.
- 开发高效的单瓶序列反应和催化级联,以访问bicyclo[5.3.0]decane骨架.
主要方法:
- 金属催化 [5+2] 乙烯基cyclopropanes (VCPs) 与enynones的循环添加.
- 随后的纳扎罗夫循环化形成的二烯循环载荷导管.
- 开发使用单一催化剂的单一操作 [5+2]/纳扎罗夫序列反应和催化级联.
主要成果:
- 从VCPs和enynones中有效形成二烯循环载荷导管.
- 在随后的纳扎罗夫循环化中成功地应用了这些引证.
- 展示了一瓶 [5+2]/纳扎罗夫连续反应的效率提高 (反应时间缩短,产量可比或更高).
- 确定能够调解这两种转换的单一催化剂.
结论:
- 开发的 [5+2]/纳扎罗夫反应序列为bicyclo[5.3.0]decane骨架提供了一种新且简单的合成策略.
- 这种方法可以从简单且易于获得的原始材料获得有价值的脚手架.
- 一瓶式方法提高了合成效率和原子经济.
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