A platform for on-the-complex annulation reactions with transient aryne intermediates

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. Organometallic complexes have numerous applications in chemistry and biology, but diversification of their structures is synthetically challenging. Here, the authors report a versatile platform for on-the-complex annulation reactions using transient aryne intermediates to access pi-extended polypyridyl complexes.

Automated summary

The study presents a versatile platform for on-the-complex annulation reactions using transient aryne intermediates to access pi-extended polypyridyl complexes, providing an effective strategy for annulating organometallic complexes and accessing complex metal-ligand scaffolds.