Metal-Site-Controlled Arene Coordination in a Heterobimetallic Bi−Rh Complex with Pyrene

• Published in: Organometallics Vol. 27; no. 15; pp. 3728 - 3735
• Main Authors: Dikarev, Evgeny V, Li, Bo, Rogachev, Andrey Yu, Zhang, Haitao, Petrukhina, Marina A
• Format: Journal Article
• Language: English
• Published: American Chemical Society 11.08.2008
• ISSN: 0276-7333; 1520-6041
• DOI: 10.1021/om8001763

The reactivity of a heterobimetallic Bi−Rh trifluoroacetate paddlewheel complex toward an aromatic substrate has been tested in a solvent-free environment. As a result of the gas phase codeposition of [BiRh(O2CCF3)4] with pyrene, a novel organometallic product, [BiRh(O2CCF3)4·(C16H10)]∞, has been isolated in the single crystalline form. An X-ray diffraction study revealed an extended 1D polymeric structure with different metal−π-arene bonding at the Bi and Rh axial sites of the heterobimetallic core. Specifically, η6-coordination of pyrene at the Bi end and η2-coordination at the Rh end have been found crystallographically and then confirmed computationally. The title product thus provides a unique example of site-controlled arene coordination by a heterobimetallic Bi−Rh unit. DFT methods have been used to rationalize the bonding and to evaluate the energetics of metal−π-arene interactions at the opposite ends of [BiRh(O2CCF3)4]. The results were compared with the corresponding data for homometallic analogues [Rh2(O2CCF3)4·(C16H10)]∞ and [Bi2(O2CCF3)4·(C16H10)]∞. The synthesis, structural, and DFT studies of the latter are reported here for the first time.