Multiple C−H Bond Activations in Corannulene by a Dirhenium Complex

• Published in: Chemistry : a European journal Vol. 25; no. 16; pp. 4234 - 4239
• Main Authors: Adams, Richard D., Dhull, Poonam, Pennachio, Matthew, Petrukhina, Marina A., Smith, Mark D.
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 15.03.2019
• Subjects: Activation; Benzene; Chemical bonds; Chemistry; corannulene; Crystal structure; C−H activation; Isomers; Ligands; metalation; oxidative addition; rhenium; Single crystals; X-ray diffraction; Yield; corannulene; rhenium; C−H activation; metalation; oxidative addition
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.201806405

The reaction of Re2(CO)8(μ‐C6H5)(μ‐H), 1 with corannulene (C20H10) yielded the product Re2(CO)8(μ‐H)(μ‐η2‐1,2‐C20H9), 2 (65 % yield) containing a Re2 metalated corannulene ligand formed by loss of benzene from 1 and the activation of one of the CH bonds of the nonplanar corannulene molecule by an oxidative‐addition to 1. The corannulenyl ligand has adopted a bridging η2‐σ+π coordination to the Re2(CO)8 grouping. Compound 2 reacts with a second equivalent of 1 to yield three isomeric doubly metalated corannulene products: Re2(CO)8(μ‐H)(μ‐η2‐1,2‐μ‐η2‐10,11‐C20H8)Re2(CO)8(μ‐H), 3 (35 % yield), Re2(CO)8(μ‐H)(μ‐η2‐2,1‐μ‐η2‐10,11‐C20H8)Re2(CO)8(μ‐H), 4 (12 % yield), and Re2(CO)8(μ‐H)(μ‐η2‐1,2‐μ‐η2‐11,10‐C20H8)Re2(CO)8(μ‐H), 5 (12 % yield), by a second CH activation on a second rim double bond on the corannulene molecule. The isomers differ by the relative orientations of the coordinated Re2(CO)8(μ‐H) groupings. All new products were characterized structurally by single crystal X‐ray diffraction analysis. The addition of Re2(CO)8 groupings to corannulene has yielded the first metalated dirheniumcorannulenyl complex and three isomers of doubly metalated bis(dirhenium)corannulendiyl complexes by CH oxidative addition reactions.