Ruthenium-Catalyzed Reductive Cleavage of Unstrained Aryl–Aryl Bonds: Reaction Development and Mechanistic Study

Cleavage of carbon–carbon bonds has been found in some important industrial processes, for example, petroleum cracking, and has inspired development of numerous synthetic methods. However, nonpolar unstrained C­(aryl)–C­(aryl) bonds remain one of the toughest bonds to be activated. As a detailed stu...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Journal of the American Chemical Society 2019-11, Vol.141 (46), p.18630-18640
Hauptverfasser: Zhu, Jun, Chen, Peng-hao, Lu, Gang, Liu, Peng, Dong, Guangbin
Format: Artikel
Sprache:eng
Schlagworte:
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:Cleavage of carbon–carbon bonds has been found in some important industrial processes, for example, petroleum cracking, and has inspired development of numerous synthetic methods. However, nonpolar unstrained C­(aryl)–C­(aryl) bonds remain one of the toughest bonds to be activated. As a detailed study of a fundamental reaction mode, here a full story is described about our development of a Ru-catalyzed reductive cleavage of unstrained C­(aryl)–C­(aryl) bonds. A wide range of biaryl compounds that contain directing groups (DGs) at 2,2′ positions can serve as effective substrates. Various heterocycles, such as pyridine, quinoline, pyrimidine, and pyrazole, can be employed as DGs. Besides hydrogen gas, other reagents, such as Hantzsch ester, silanes, and alcohols, can be employed as terminal reductants. The reaction is pH neutral and free of oxidants; thus a number of functional groups are tolerated. Notably, a one-pot C–C activation/C–C coupling has been realized. Computational and experimental mechanistic studies indicate that the reaction involves a ruthenium­(II) monohydride-mediated C­(aryl)–C­(aryl) activation and the resting state of the catalyst is a η4-coordinated ruthenium­(II) dichloride complex, which could inspire development of other transformations based on this reaction mode.
ISSN:0002-7863
1520-5126
DOI:10.1021/jacs.9b11605