Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA.
Nat Commun. 2021 Jun 17;12(1):3706. doi: 10.1038/s41467-021-23970-8.
Organometallic complexes are ubiquitous in chemistry and biology. Whereas their preparation has historically relied on ligand synthesis followed by coordination to metal centers, the ability to efficiently diversify their structures remains a synthetic challenge. A promising yet underdeveloped strategy involves the direct manipulation of ligands that are already bound to a metal center, also known as chemistry-on-the-complex. Herein, we introduce a versatile platform for on-the-complex annulation reactions using transient aryne intermediates. In one variant, organometallic complexes undergo transition metal-catalyzed annulations with in situ generated arynes to form up to six new carbon-carbon bonds. In the other variant, an organometallic complex bearing a free aryne is generated and intercepted in cycloaddition reactions to access unique scaffolds. Our studies, centered around privileged polypyridyl metal complexes, provide an effective strategy to annulate organometallic complexes and access complex metal-ligand scaffolds, while furthering the synthetic utility of strained intermediates in chemical synthesis.
金属有机配合物在化学和生物学中无处不在。虽然它们的制备历史上依赖于配体的合成，然后再与金属中心配位，但有效地多样化其结构仍然是一个合成挑战。一种有前途但尚未开发的策略涉及到对已经与金属中心配位的配体的直接操作，也称为配合物上的化学。在此，我们介绍了一种使用瞬态芳炔中间体进行配合物环化反应的多功能平台。在一种变体中，金属有机配合物经历过渡金属催化的与原位生成的芳炔的环化反应，形成多达六个新的碳-碳键。在另一种变体中，生成带有游离芳炔的金属有机配合物，并在加成反应中拦截，以获得独特的支架。我们的研究集中在特权多吡啶金属配合物上，为金属有机配合物的环化和复杂的金属-配体支架的获得提供了一种有效的策略，同时进一步提高了在化学合成中应变中间体的合成实用性。
