Agostic interaction and intramolecular proton transfer from the protonation of dihydrogen ortho metalated ruthenium complexes

Toner, Andrew J.; Matthes, Jochen; Gründemann, Stephan; Limbach, Hans−Heinrich; Chaudret, Bruno; Clot, Eric; Sabo-Étienne, Sylviane

doi:10.1073/pnas.0608979104

Cited by 53 publications

(44 citation statements)

References 51 publications

(51 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Hindered rotation about the Ge–C ipso bond may result in two distinct H signals. Similar interactions between metal atoms such as Li, Ru or Ir and H were previously shown to cause such a hindered rotation and a high field shift of the involved o ‐H atoms …”

Section: Resultssupporting

confidence: 52%

Hydroalumination of Oligoalkynylgermanes and ‐digermanes – Reactions with Heterocumulenes by Al–C or Ge–C Bond Activation and Formation of a Hexazenedialuminum Complex

Uhl

Honacker

Lawrence

et al. 2018

Zeitschrift anorg allge chemie

View full text Add to dashboard Cite

Hydroalumination of the dialkynylgermane Ph2Ge(C≡CtBu)2 (1) and the digermanes Phn(tBuC≡C)3–nGe–Ge(C≡CtBu)3–nPhn (2a: n = 2; 2b: n = 1) with two equivalents of H–AltBu2 or H–AlEt2 yielded the mixed Al/Ge compounds Ph2Ge[C(AltBu2)=CH‐tBu]2 (3), [Ph2GeC(AltBu2)=CH‐tBu]2 (4a), and [Ph2GeC(AlEt2)=CH‐tBu]2 (4b). Reactions of 2b with both aluminum hydrides afforded inseparable mixtures of products. 3 reacted with heterocumulenes by retrohydroalumination. Phenyl isocyanate gave insertion of the C=N group into the resulting Ge–C(≡C–tBu) bond (5), whereas the NCS and NCN groups of phenyl isothiocyanate and a carbodiimide inserted into Al–Cvinyl bonds (6 and 7) with unaffected terminal Ge–C≡C–tBu moieties. The generation of 5 represents the first example of the insertion of a heterocumulene into a Ge–C bond, which may be favored by the activation of the isocyanate group by the Lewis acidic Al atom and the increased polarity of the N=C=O fragment as determined by NBO calculations. The reactions of the digermanes 4 with heterocumulenes were unselective and afforded inseparable mixtures. Treatment of 4a with the azide (4‐tBu)C6H4CH2–N3 led interestingly to reductive coupling of two azide molecules, and the hexazene complex (tBuC6H4CH2N3–N3C6H4tBu)(AltBu2)2 (8) was isolated in moderate yield. Six nitrogen atoms form a dianionic chain, which coordinated two AltBu2 fragments by formation of two joint AlN4 heterocycles.

show abstract

Section: Resultssupporting

confidence: 52%

Hydroalumination of Oligoalkynylgermanes and ‐digermanes – Reactions with Heterocumulenes by Al–C or Ge–C Bond Activation and Formation of a Hexazenedialuminum Complex

Uhl

Honacker

Lawrence

et al. 2018

Zeitschrift anorg allge chemie

View full text Add to dashboard Cite

show abstract

“…DFT-based electron localization function (ELF) analyses [20] and geometry optimizations [22] supported the lack of agostic interactions in these complexes. This absence has been attributed to the strong trans influence exerted by the ligand in trans position with respect to the vacant site [23–24]. …”

Section: Reviewmentioning

confidence: 99%

“…Although a remote contact is described in A11a , the largest distances correspond with the γ-agostic A8 . In other words, the strength of the agostic interaction is not only governed by geometrical constraints and the surroundings of the CH group, but also by the trans influence of the ligand in trans position with respect to the agostic interaction [23–24]. In this case, the boryl ligand in A8 exhibits a higher trans influence than the alkyl group in A11a [45–46], and therefore the agostic interaction in the former is weaker.…”

Section: Reviewmentioning

confidence: 99%

True and masked three-coordinate T-shaped platinum(II) intermediates

Ortuño¹,

Conejero²,

Lledós³

2013

Beilstein J. Org. Chem.

View full text Add to dashboard Cite

SummaryAlthough four-coordinate square-planar geometries, with a formally 16-electron counting, are absolutely dominant in isolated Pt(II) complexes, three-coordinate, 14-electron Pt(II) complexes are believed to be key intermediates in a number of platinum-mediated organometallic transformations. Although very few authenticated three-coordinate Pt(II) complexes have been characterized, a much larger number of complexes can be described as operationally three-coordinate in a kinetic sense. In these compounds, which we have called masked T-shaped complexes, the fourth position is occupied by a very weak ligand (agostic bond, solvent molecule or counteranion), which can be easily displaced. This review summarizes the structural features of the true and masked T-shaped Pt(II) complexes reported so far and describes synthetic strategies employed for their formation. Moreover, recent experimental and theoretical reports are analyzed, which suggest the involvement of such intermediates in reaction mechanisms, particularly C–H bond-activation processes.

show abstract

“…The Ir−C cyclometalation to generate 4 induced by H 2 activation is remarkable because the reverse reactivity is typically observed, that is, hydrogenation of the cyclometalated species to the corresponding hydrido complexes. This has been demonstrated by many examples, but cyclometalation induced by H 2 activation is still scarce . The viability of the proposed reaction mechanism for the cyclometalation of 2 has also been confirmed by DFT studies on a model system (Cp instead of Cp* and methyl groups instead of phenyl at phosphorus).…”

Section: Resultsmentioning

confidence: 72%

“…This has been demonstrated by many examples, [20] but cyclometalation induced by H 2 activation is still scarce. [21] The viability of the proposed reactionm echanism for the cyclometalation of 2 has also been confirmed by DFT studies on am odel system (Cp insteado f Cp* and methyl groups instead of phenyl at phosphorus). Figure 5d isplays the calculated mechanism and corresponding reactionp rofile.…”

Section: Hàhactivation and Dehydrogenation With Iridium Carbene Complmentioning

confidence: 72%

Metal‐Ligand Cooperativity in a Methandiide‐Derived Iridium Carbene Complex

Weismann

Waterman

Gessner

2016

Chemistry A European J

View full text Add to dashboard Cite

The synthesis, electronic structure, and reactivity of the first Group 9 carbene complex, [Cp*IrL] [L=C(Ph2 PS)(SO2 Ph)] (2), based on a dilithio methandiide are reported. Spectroscopic as well as computational studies have shown that, despite using a late transition-metal precursor, sufficient charge transfer occurred from the methandiide to the metal, resulting in a stable, nucleophilic carbene species with pronounced metal-carbon double-bond character. The potential of this iridium complex in the activation of a series of E-H bonds by means of metal-ligand cooperation has been tested. These studies have revealed distinct differences in the reactivity of 2 compared to a previously reported ruthenium analogue. Whereas attempts to activate the O-H bond in different phenol derivatives resulted in ligand cleavage, H-H and Si-H activation as well as dehydrogenation of isopropanol have been accomplished. These reactions are driven by the transformation of the carbene to an alkyl ligand. Contrary to a previously reported ruthenium carbene system, the dihydrogen activation has been found to proceed by a stepwise mechanism, with the activation first taking place solely at the metal. The activated products further reacted to afford a cyclometalated complex through liberation of the activated substrates. In the case of triphenylsilane, cyclometalation could thus be induced by a substoichiometric (i.e., catalytic) amount of silane.

show abstract

Agostic interaction and intramolecular proton transfer from the protonation of dihydrogen ortho metalated ruthenium complexes

Cited by 53 publications

References 51 publications

Hydroalumination of Oligoalkynylgermanes and ‐digermanes – Reactions with Heterocumulenes by Al–C or Ge–C Bond Activation and Formation of a Hexazenedialuminum Complex

Hydroalumination of Oligoalkynylgermanes and ‐digermanes – Reactions with Heterocumulenes by Al–C or Ge–C Bond Activation and Formation of a Hexazenedialuminum Complex

True and masked three-coordinate T-shaped platinum(II) intermediates

Metal‐Ligand Cooperativity in a Methandiide‐Derived Iridium Carbene Complex

Contact Info

Product

Resources

About