Reactivity of the Unsaturated Complex [(C₆Me₆)₂Ru₂(μ₂-H)₃]⁺toward Phosphines:  Synthesis and Molecular Structure of the Dinuclear Cations [(C₆Me₆)₂Ru₂(μ₂-PR₂)(μ₂-H)₂]⁺and Characterization of the P−C Bond Activation Intermediate [(C₆Me₆)₂Ru₂(μ₂-PPh₂)(μ₂-H)(μ<

Abstract

The unsaturated trihydrido complex [(C 6 Me 6 ) 2 Ru 2 (µ 2 -H) 3 ] + reacts with diaryl-or dialkylphosphines PR 2 H to give the dinuclear cations 4) are also accessible in high yield from the reaction of [(C 6 Me 6 ) 2 Ru 2 -(µ 2 -H) 3 ] + with the corresponding triaryl-or trialkylphosphine PPh 3 , P(n-Bu) 3 , or P(n-Oct) 3 by carbon-phosphorus bond cleavage. A possible intermediate of the reaction with PPh 3 , [(C 6 Me 6 ) 2 Ru 2 (µ 2 -PPh 2 )(µ 2 -H)(µ 2 -Ph)] + (5), could be isolated from the reaction mixture as the tetrafluoroborate salt, the single-crystal X-ray structure analysis of which reveals a bridging phenyl ligand coordinated in an η 1 -µ 2 fashion to the diruthenium backbone. With the mixed phosphine PMe 2 Ph, [(C 6 Me 6 ) 2 Ru 2 (µ 2 -H) 3 ] + reacts to give [(C 6 Me 6 ) 2 Ru 2 (µ 2 -PMe 2 )(µ 2 -H) 2 ] + (6) and the corresponding intermediate [(C 6 Me 6 ) 2 Ru 2 (µ 2 -PMe 2 )(µ 2 -H)(µ 2 -Ph)] + (7). All dinuclear cations are isolated as the tetrafluoroborate salts.

A Surprising Reaction of Trimethylphosphane with the Unsaturated Diruthenium Complex [(η6‐C6Me6)2Ru2(μ2‐H)3]+: Synthesis and Molecular Structure of the Cations [(η6‐C6Me6)Ru2(PMe3)3(μ2‐H)3]+ and [(η6‐C6Me6)2Ru2(PMe3)2(μ2‐H)(H)2Tschan1, Cherioux2, Therrien3 et al. 2007Eur J Inorg ChemSelf Cite6120View full textAdd to dashboardCite

“…2.258 Å) are comparable to those found in [Ru 2 (PMe 3 ) 6 (µ 2 -H) 3 ] + . [8] In the 1 H NMR spectrum the nine methyl protons give rise to a broad signal, each carbon atom of the three equivalent PMe 3 ligands can be differentiated in the 13 C NMR spectrum (i.e.…”

“…[7] The replacement of a hexamethylbenzene ligand by three PMe 3 ligands does not significantly affect the geometrical parameters of the Ru 2 (µ 2 -H) 3 backbone as compared to [(η 6 -C 6 Me 6 ) 2 Ru 2 (µ 2 -H) 3 ] + .…”

“…[1] The cleavage of the carbon-phosphorus bond has been observed in numerous cases, essentially by reacting metal carbonyl complexes with aromatic phosphanes. [2] Recently, we found that trisubstituted (aliphatic or aromatic) phosphanes, PR 3 , undergo facile P-C bond cleavage with the unsaturated complex [(η 6 -C 6 Me 6 ) 2 Ru 2 (µ 2 -H) 3 ] + to give the phosphido-bridged complexes [(η 6 -C 6 Me 6 ) 2 Ru 2 (µ 2 -PR 2 )(µ 2 -H) 2 ] + . [3] In the reaction of triphenylphosphane with [(η 6 -C 6 Me 6 ) 2 Ru 2 (µ 2 -H) 3 ] + to give [(η 6 -C 6 Me 6 ) 2 Ru 2 (µ 2 -PPh 2 )(µ 2 -H) 2 ] + , we were able to isolate an intermediary complex containing a bridging phenyl ligand, [(η 6 -C 6 Me 6 ) 2 Ru 2 (µ 2 -PPh 2 )(µ 2 -Ph)(µ 2 -H)] + , and to perform a single-crystal X-ray structure analysis of the tetrafluoroborate salt.…”

“…[2] Recently, we found that trisubstituted (aliphatic or aromatic) phosphanes, PR 3 , undergo facile P-C bond cleavage with the unsaturated complex [(η 6 -C 6 Me 6 ) 2 Ru 2 (µ 2 -H) 3 ] + to give the phosphido-bridged complexes [(η 6 -C 6 Me 6 ) 2 Ru 2 (µ 2 -PR 2 )(µ 2 -H) 2 ] + . [3] In the reaction of triphenylphosphane with [(η 6 -C 6 Me 6 ) 2 Ru 2 (µ 2 -H) 3 ] + to give [(η 6 -C 6 Me 6 ) 2 Ru 2 (µ 2 -PPh 2 )(µ 2 -H) 2 ] + , we were able to isolate an intermediary complex containing a bridging phenyl ligand, [(η 6 -C 6 Me 6 ) 2 Ru 2 (µ 2 -PPh 2 )(µ 2 -Ph)(µ 2 -H)] + , and to perform a single-crystal X-ray structure analysis of the tetrafluoroborate salt. In the reaction of trialkylphosphanes with [(η 6 -C 6 Me 6 ) 2 Ru 2 (µ 2 -H) 3 ] + to give [(η 6 -C 6 Me 6 ) 2 -Ru 2 (µ 2 -PR 2 )(µ 2 -H) 2 ] + (R = nOct, nBu), we were able to show that the reaction produces the corresponding olefins (n-octene or n-butene) and not the expected alkanes.…”

“…[3] In the reaction of triphenylphosphane with [(η 6 -C 6 Me 6 ) 2 Ru 2 (µ 2 -H) 3 ] + to give [(η 6 -C 6 Me 6 ) 2 Ru 2 (µ 2 -PPh 2 )(µ 2 -H) 2 ] + , we were able to isolate an intermediary complex containing a bridging phenyl ligand, [(η 6 -C 6 Me 6 ) 2 Ru 2 (µ 2 -PPh 2 )(µ 2 -Ph)(µ 2 -H)] + , and to perform a single-crystal X-ray structure analysis of the tetrafluoroborate salt. In the reaction of trialkylphosphanes with [(η 6 -C 6 Me 6 ) 2 Ru 2 (µ 2 -H) 3 ] + to give [(η 6 -C 6 Me 6 ) 2 -Ru 2 (µ 2 -PR 2 )(µ 2 -H) 2 ] + (R = nOct, nBu), we were able to show that the reaction produces the corresponding olefins (n-octene or n-butene) and not the expected alkanes. This suggests that the P-C bond cleavage in trialkylphosphanes at the diruthenium centre occurs by β-H elimination from the alkyl group.…”