固态诱导控制动力不稳定的立体异构体
Joseph M Keane1, Fei Ding, Michal Sabat
1Department of Chemistry, University of Virginia, Charlottesville, Virginia 22901, USA.
Journal of the American Chemical Society
|January 22, 2004
概括
含有前性的金属复合物存在于溶液中的动态二聚体,但在固态中作为单个二聚体. 这种固态选择性使得在受束的区域上能够产生立体选择性反应.
科学领域:
- 有机金属化学 有机金属化学
- 立体化学是一种立体化学.
- 固态化学 固态化学
背景情况:
- 形式为TpM ((pi-acid) ((L) ((eta2-arene) 的烯复合物具有一个二 ((pyrazolyl) 酸连接体和一个金属中心 (Re,Mo,W).
- 这些复合物涉及pi-酸联体 (CO,NO) 和辅助联体 (1-alkylimidazole,pyridine,PMe3),具有亲的eta2-arene.
- 了解这些复合体在不同阶段的立体化学行为对于设计立体选择性反应至关重要.
研究的目的:
- 研究TPM (p-酸) (L) (乙二烯) 复合体的溶液和固态二聚体态态的行为.
- 通过利用固态特性,探索结合基部分的立体选择性反应的潜力.
- 阐明固体相对涉及近皮性的反应的立体化学结果的影响.
主要方法:
- 合成各种具有不同金属中心和连接体的各种烯复合物.
- 溶液核磁共振光谱法用于研究协调二聚体的动态平衡.
- 用X射线晶体学来确定固态结构和二聚体组成.
- 在溶液和固体状态下对结合的基进行化学转换.
主要成果:
- 复合体存在于溶液中的协调二聚体的动态平衡.
- 在晶体和无形固体状态中,只能观察到单个二聚体.
- 在固态中对结合场进行的反应是立体选择性的.
- 固体相的同型性质决定了立体化学结果.
结论:
- 固态提供了一个平台,用于控制arene复合体中的立体化学.
- 利用二聚体纯固体相,可以实现对近皮性的高度立体选择性功能化.
- 这项工作展示了通过固态效应在有机金属化学中实现立体控制的策略.
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