在第4组二甲基复合物的M-C键中插入异二烯
Jiawei Chen1, Nadine Yassin2, Thilina Gunasekara1
1Department of Chemistry , Columbia University , 3000 Broadway , New York , New York 10027 , United States.
Journal of the American Chemical Society
|June 17, 2018
概括
具有受约束几何联体的4组金属复合物与二烯和异二烯反应. 形成了-亚齐里丁,而和哈夫产生了复杂的二甲环衍生物,揭示了不同的反应途径.
科学领域:
- 有机金属化学
- 协调化学
- 有机合成
背景情况:
- 约束几何 (cg) 连接物对于稳定反应性金属中心至关重要.
- 2,3-二甲基在有机金属化学中充当多功能联体.
- 异烯是有机金属转化中的反应性构件.
研究的目的:
- 合成和表征4组金属的2,3-二甲基丁烯复合物与受约束的几何连接物.
- 研究这些复合物的与异二烯的反应性.
- 阐明这些有机金属复合物的反应机制.
主要方法:
- 合成4组金属复合物与受约束的几何连接物.
- 金属复合物的反应与2,3-二甲基丁和各种异二烯 (例如,三甲基丁二氧化,西二氧化).
- 产品的光谱表征 (例如NMR) 和结构分析.
主要成果:
- Ti,Zr 和 Hf 的 2,3-二甲基丁烯复合体采用 σ2,π 结合的垂直方向.
- 复合物通过 [4+1] 循环添加与三基异化物发生反应,形成亚.
- 和哈夫复合物与异烯反应,产生不对称的2,5-甲cyclopentane衍生物或对称的2,5-甲cyclopentene复合物.
- 机理学研究显示 (还原性消除) 和哈夫 (协调/插入) 复合物的不同途径.
结论:
- 具有受约束几何联体的4组金属复合物的反应性高度依赖于金属中心.
- 观察到不同的机制路径,包括循环添加,减少消除和协调/插入.
- 这些发现有助于理解有机金属反应机制和新合成方法的开发.
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