Five-membered OsC3N heterocycles from osmium azavinylidenes as precursors

Werner, Helmut; Daniel, Thomas; Braun, Thomas; Nürnberg, Oliver

doi:10.1016/0022-328x(94)87110-8

Cited by 23 publications

(14 citation statements)

References 24 publications

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“…The Os−N bond length of 2.097(3) Å and the Os−C(3) bond distance of 2.069 Å are typical for Os−N and Os−C(aryl) single bonds, respectively, and are in agreement with the values previously found for the complexes (2.106(7) and 2.089(7) Å), (2.083(4) and 2.072(4) Å), (2.119(5) and 2.100(7) Å), and fac -Os{ C , N -3-Me[2-(MeC 6 H 4 )NCMe 3 ]C 6 H 3 }(2-Me-C 6 H 4 )(CN- t Bu) 3 (2.193(24) and 2.077(20) Å) …”

Section: Resultssupporting

confidence: 90%

Synthesis and Characterization of OsX{NHC(Ph)C₆H₄}H₂(PⁱPr₃)₂ (X = H, Cl, Br, I): Nature of the H₂ Unit and Its Behavior in Solution

et al. 1998

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The hexahydride OsH6(PiPr3)2 (1) reacts with benzophenone imine to give the trihydride derivative (2). The three hydride ligands and the bidentate group of 2 are situated in the equatorial plane of a pentagonal-bipyramidal arrangement of ligands around the metallic center. In solution, two thermally activated exchange processes take place between these hydride ligands, one of them faster than the other one. The reaction of 2 with HCl leads to OsH3Cl(NHCPh2)(PiPr3)2 (3), which evolves in solution into the elongated dihydrogen compound (4). Complex 4 and the related compounds (X = Br (5), I (6)) can be also prepared by protonation of 2 with HBF4·OEt2 in dichloromethane and subsequent treatment with NaX (X = Cl, Br, I). The structure of 4 has been determined by X-ray diffraction. The geometry around the osmium atom can be described as a distorted octahedron, with the triisopropylphosphine ligands occupying two relative trans positions. The remaining perpendicular plane is formed by the mutually cis disposed chloro and dihydrogen ligands and the metalated benzophenone imine group, which has a bite angle of 75.1(1)°. The H2 unit of 4−6 shows a restricted rotational motion in solution. Thus, the 1H NMR spectra in the high-field region are a function of the temperature. Lowering the sample temperature leads to a broadening of the dihydrogen resonances. At 213 K, decoalescence occurs, and at 193 K, two signals are clearly observed. Theoretical calculations suggest that the transition states for the hydrogen exchanges in 2 and 4−6 present dihydrogen-like nature.

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Section: Resultssupporting

confidence: 90%

Synthesis and Characterization of OsX{NHC(Ph)C₆H₄}H₂(PⁱPr₃)₂ (X = H, Cl, Br, I): Nature of the H₂ Unit and Its Behavior in Solution

et al. 1998

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“… Imine coordination followed by C–H cleavage to form a five-membered ring is crucial for the transformation. Benzo-fused osmapyrroles were synthesized analogously . In addition, Esteruelas and co-workers reported a tricyclic diosmium aromatic system formed by the fusion of a central six-membered ring with two osmapyrrole rings …”

Section: Synthetic Methodsmentioning

confidence: 99%

“…Benzo-fused osmapyrroles were synthesized analogously. 328 In addition, Esteruelas and coworkers reported a tricyclic diosmium aromatic system formed by the fusion of a central six-membered ring with two osmapyrrole rings. 329 Bleeke and co-workers have made use of (η 2 -cyclooctene)-IrCl(PMe 3 ) 3 to react with the N-lithiated imine reagent, which was synthesized by treatment of benzonitrile with MeLi in situ, to build an intermediate with a N−Ir σ bond.…”

Section: Synthesis Of Heterometallaaromaticsmentioning

confidence: 99%

“…Complex 684 could be reproduced, if HPF 6 is added into a solution of 685 (Scheme 215). 328 As a typical reaction of organic aromatic halides, Sonogashira coupling has been applied to metallapyrroles with a halogen substituent on the metallacycle. The Leong group treated iridaindolizines 318 and 319 with HCCSiMe 3 in the presence of Pd(PPh 3 ) 4 , diisopropylamine, and CuI to afford alkyne-substituted analogues 686 and 687 (Scheme 216).…”

Section: Reactivities Of Metallabenzynesmentioning

confidence: 99%

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Metallaaromatic Chemistry: History and Development

2020

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Since the prediction of the existence of metallabenzenes in 1979, metallaaromatic chemistry has developed rapidly, due to its importance in both experimental and theoretical fields. Now six major types of metallaromatic compounds, metallabenzenes, metallabenzynes, heterometallaaromatics, dianion metalloles, metallapentalenes and metallapentalynes (also termed carbolongs), and spiro metalloles, have been reported and extensively studied. Their parent organic analogues may be aromatic, non-aromatic, or even anti-aromatic. These unique systems not only enrich the large family of aromatics, but they also broaden our understanding and extend the concept of aromaticity. This review provides a comprehensive overview of metallaaromatic chemistry. We have focused on not only the six major classes of metallaaromatics, including the main-group-metal-based metallaaromatics, but also other types, such as metallacyclobutadienes and metallacyclopropenes. The structures, synthetic methods, and reactivities are described, their applications are covered, and the challenges and future prospects of the area are discussed. The criteria commonly used to judge the aromaticity of metallaaromatics are presented.

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“…Benzophenone imine has recently become commercially available, and this has allowed a considerable development of its inorganic chemistry. In mononuclear compounds, its coordination chemistry is represented by Mo, W, Fe, Ru, Os, − Rh, Ir, , and Ni complexes corresponding to the coordination types shown in Chart , which involve η 1 -terminal ligands ( A , B ), η 2 -terminal ligands ( C ), and orthometalated ligand derivatives ( D , E ). Binuclear complexes derived from this ligand have only been reported for Mo, W, Fe, Rh, and Ir 2 ( F ) (Chart ).…”

Section: Introductionmentioning

confidence: 99%

Synthesis and Reactivity of Triruthenium Carbonyl Cluster Complexes Containing a Bridging 1-Azavinylidene Ligand Derived from Benzophenone Imine

et al. 1996

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The reaction of [Ru3(CO)12] with the lithium salt of benzophenone imine (LiNCPh2) followed by protonation with trifluoroacetic acid leads to the η1-1-azavinylidene cluster complex [Ru3(μ-H)(μ-NCPh2)(CO)10] (1). Compound 1 cannot be prepared by direct reaction of [Ru3(CO)12] with benzophenone imine under thermal conditions. Carbonyl substitution and thermolysis reactions on compound 1 and on some of its derivatives are described. Complex 1 reacts with 1 and 2 equiv of bis(diphenylphosphino)methane (dppm) at room temperature to give the substituted derivatives [Ru3(μ-H)(μ-NCPh2)(μ-dppm)(CO)8] (2) and [Ru3(μ-H)(μ-NCPh2)(μ-dppm)(dppm)(CO)7] (3), respectively. In both complexes the three bridging ligands span the same Ru−Ru edge; in addition, complex 3 contains an η1-dppm ligand occupying an equatorial site on the unique Ru atom. An X-ray structure analysis of 3·0.5CH2Cl2 is reported. Thermolysis of complex 2 in THF at reflux temperature leads to [Ru3(μ-H)(μ3-NCPh2)(μ-dppm)(CO)7] (4), a compound which contains a bridging η2-1-azavinylidene ligand interacting with the three Ru atoms. Complex 4 reacts with CO (1 atm, 18 °C) reverting to complex 2. The reaction of compound 1 with PPh3 at room temperature gives the monosubstituted derivative [Ru3(μ-H)(μ-NCPh2)(PPh3)(CO)9] (5), in which the P-donor ligand is attached to one of the two bridged Ru atoms. Thermolysis of 5 in THF at reflux temperature leads to [Ru3(μ-H)(μ3-NCPh2)(PPh3)(CO)8] (6), which, as complex 4, contains a face-bridging η2-1-azavinylidene ligand. The reaction of complex 5 with PPh3 occurs only at higher temperatures (40−70 °C) to give the asymmetrically disubstituted derivative [Ru3(μ-H)(μ-NCPh2)(PPh3)2(CO)8] (7), which has the additional PPh3 ligand attached to the unbridged Ru atom. Compound 7 is thermally unstable, undergoing an easy (40−70 °C) orthometalation reaction of a phenyl ring of the azavinylidene ligand to give the derivative [Ru3(μ-H)2(μ-NCPhC6H4)(PPh3)2(CO)7] (8). This compound reacts with CO (1 atm, 18 °C) to regenerate complex 7.

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Five-membered OsC3N heterocycles from osmium azavinylidenes as precursors

Cited by 23 publications

References 24 publications

Synthesis and Characterization of OsX{NHC(Ph)C₆H₄}H₂(PⁱPr₃)₂ (X = H, Cl, Br, I): Nature of the H₂ Unit and Its Behavior in Solution

Synthesis and Characterization of OsX{NHC(Ph)C₆H₄}H₂(PⁱPr₃)₂ (X = H, Cl, Br, I): Nature of the H₂ Unit and Its Behavior in Solution

Metallaaromatic Chemistry: History and Development

Synthesis and Reactivity of Triruthenium Carbonyl Cluster Complexes Containing a Bridging 1-Azavinylidene Ligand Derived from Benzophenone Imine

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Five-membered OsC3N heterocycles from osmium azavinylidenes as precursors

Cited by 23 publications

References 24 publications

Synthesis and Characterization of OsX{NHC(Ph)C6H4}H2(PiPr3)2 (X = H, Cl, Br, I): Nature of the H2 Unit and Its Behavior in Solution

Synthesis and Characterization of OsX{NHC(Ph)C6H4}H2(PiPr3)2 (X = H, Cl, Br, I): Nature of the H2 Unit and Its Behavior in Solution

Metallaaromatic Chemistry: History and Development

Synthesis and Reactivity of Triruthenium Carbonyl Cluster Complexes Containing a Bridging 1-Azavinylidene Ligand Derived from Benzophenone Imine

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Synthesis and Characterization of OsX{NHC(Ph)C₆H₄}H₂(PⁱPr₃)₂ (X = H, Cl, Br, I): Nature of the H₂ Unit and Its Behavior in Solution

Synthesis and Characterization of OsX{NHC(Ph)C₆H₄}H₂(PⁱPr₃)₂ (X = H, Cl, Br, I): Nature of the H₂ Unit and Its Behavior in Solution