[(η5-C5Me5)Ru]+ fragments ligated to polyaromatic hydrocarbons: an experimental and computational approach to pathways for haptotropic migration12. Issue 1 (10th November 2014)

• Record Type: Journal Article
• Authors: Rioja, Matias; Hamon, Paul; Roisnel, Thierry; Sinbandhit, Sourisak; Fuentealba, Mauricio; Letelier, Karina; Saillard, Jean-Yves; Vega, Andrés; Hamon, Jean-René
• Is Part Of: Dalton transactions. Volume 44:Issue 1(2015)
• Page Start: 316
• Page End: 329
• Publication Date: 2014-11-10
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/c4dt02736a
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : DFT calculations indicated rather high activation energies for the thermally induced intramolecular inter-ring haptotropic migration of the [(η 5 -C5 Me5 )Ru + ] moiety. Abstract : Ligand exchange reactions between [Cp*Ru(NCMe)3 ][PF6 ], where Cp* represents η 5 -C5 Me5, and the polycyclic aromatic hydrocarbons (PAHs) pyrene, acenaphthylene and fluoranthene afforded the known [Cp*Ru(η 6 -pyrene)][PF6 ] (1 ) and the new mixed sandwiches [Cp*Ru(η 6 -acenaphthylene)][PF6 ] (2 ) and [Cp*Ru(η 6 -fluoranthene)][PF6 ] (3 ), respectively, isolated in quantitative yields (94–100%). Complex3 is formed as a mixture of two isomers:3A as the major product where the [Cp*Ru + ] moiety is coordinated to the naphthalene fragment of fluoranthene, and3B with the coordination of the arenophile to the peripheral benzene ring, in a 90/10 spectroscopic ratio. The composition and identity of the complexes were deduced by elemental analysis, 1 H and 13 C multidimensional NMR spectroscopy, and mass spectrometry. Compounds1A, 3A and2A have been characterized using X-ray structural investigations. That showed that the [Cp*Ru + ] unit is η 6 -attached to one of the two naphthalene rings in each complex. Heating1 and3 at 90 °C in CD3 NO2 solutions or heating3 at 120 °C in the solid phase did not provide any evidence for thermally induced intramolecular inter-ring haptotropic rearrangements. These rearrangements were modelled by DFT calculations which indicated rather high activation energies.