Relay ring-closing metathesis (RRCM): A strategy for directing metal movement throughout olefin metathesis sequences
Relay ring-closing metathesis (RRCM): A strategy for directing metal movement throughout olefin metathesis sequences
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DOI：
10.1021/ja046385t
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发表时间：
2004-08-25
影响因子：
15
通讯作者：
Zhao, HY
中科院分区：
文献类型：
--
作者：
Hoye, TR;Jeffrey, CS;Zhao, HY
本发明的概念涉及使用结构修饰的RCM底物，所述RCM底物包含延伸臂，终止于远程反应性烯烃。在反应性烯烃处启动RCM序列之后，金属中心在分子内快速传递到母体底物中最初活性较低的烯烃。这允许控制化合序列的相对时序(或方向)。例如，可以逆转非对称α，ω-diene衬底的固有趋势，比如说，从左到右接近从右到左的趋势。展示了RRCM概念的四种不同类型的应用。在其他方面，他们展示了使用G1[(Cy3P)2(Cl2)RuCHPh]制备四取代缺电子烯烃，方向性(末端)的互补控制，通过加入额外的空间主体的辅助益处(酶专一性)，激活原本无效的底物用于RCM闭合，使用非正规烯作为闭环的起始点，以及产品烯烃几何形状的控制。
The title concept involves the use of structurally modified RCM substrates that contain extender arms, terminating in a remote reactive alkene. Initiation of an RCM sequence at that reactive alkene is followed by rapid intramolecular relay of the metal center to an initially less reactive alkene in the parent substrate. This permits one to control the relative timing (or direction) of a metathesis sequence. For example, one can reverse the inherent tendency of an unsymmetrical α,ω-diene substrate to close, say, left-to-right, to that of right-to-left. Four distinct types of application of the RRCM concept are demonstrated. Among other things, they show the preparation of tetrasubstituted electron-deficient alkenes usingG1[(Cy3P)2(Cl2)RuCHPh], complementary control of directionality (endedness), auxiliary benefits (enzyme specificity) from the incorporation of additional steric bulk, the activation of otherwise ineffective substrates for RCM closure, the use of unorthodox alkenes as initiation sites for ring closure, and control of product olefin geometry.