Bis{1, 4-bis(trimethylsilyl) buta-1, 3-diene} cobalt: synthesis and molecular structure

Cloke, F. Geoffrey N.; Gardiner, Michael G.; Raston, Colin L.; Simpson, S J

doi:10.1016/0022-328x(95)05736-9

Cited by 4 publications

(3 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, co-condensation of metal vapors with 1,4-bis(tert-butyl)butadiene gives corresponding [1,4-(Me 3 C) 2 C 4 H 4 ] 2 M complexes (M = Ti [ 9 ], V [ 9 ], Co [ 10 ]). Similarly, the zerovalent 1,4-bis(trimethylsilyl)butadiene cobalt open sandwich [1,4-(Me 3 Si) 2 C 4 H 4 ] 2 Co has been synthesized and structurally characterized [ 11 ].…”

Section: Introductionmentioning

confidence: 99%

Tris(Butadiene) Compounds versus Butadiene Oligomerization in Second-Row Transition Metal Chemistry: Effects of Increased Ligand Fields

Zhao

Chen

et al. 2021

Molecules

View full text Add to dashboard Cite

The geometries, energetics, and preferred spin states of the second-row transition metal tris(butadiene) complexes (C4H6)3M (M = Zr–Pd) and their isomers, including the experimentally known very stable molybdenum derivative (C4H6)3Mo, have been examined by density functional theory. Such low-energy structures are found to have low-spin singlet and doublet spin states in contrast to the corresponding derivatives of the first-row transition metals. The three butadiene ligands in the lowest-energy (C4H6)3M structures of the late second-row transition metals couple to form a C12H18 ligand that binds to the central metal atom as a hexahapto ligand for M = Pd but as an octahapto ligand for M = Rh and Ru. However, the lowest-energy (C4H6)3M structures of the early transition metals have three separate tetrahapto butadiene ligands for M = Zr, Nb, and Mo or two tetrahapto butadiene ligands and one dihapto butadiene ligand for M = Tc. The low energy of the experimentally known singlet (C4H6)3Mo structure contrasts with the very high energy of its experimentally unknown singlet chromium (C4H6)3Cr analog relative to quintet (C12H18)Cr isomers with an open-chain C12H18 ligand.

show abstract

Section: Introductionmentioning

confidence: 99%

Tris(Butadiene) Compounds versus Butadiene Oligomerization in Second-Row Transition Metal Chemistry: Effects of Increased Ligand Fields

Zhao

Chen

et al. 2021

Molecules

View full text Add to dashboard Cite

show abstract

“…However, the zerovalent cobalt 1,4-bis(trimethylsilyl)butadiene derivative [(Me 3 Si) 2 C 4 H 4 ] 2 Co was synthesized and structurally characterized in 1996. 6 In this system the bulky trimethylsilyl substituents inhibit butadiene dimerization or trimerization. Our recent theoretical studies on the unsubstituted bis(butadiene) compounds of the first-row transition metals, (C 4 H 6 ) 2 M, show that the preferred spin states of the (C 4 H 6 ) 2 M complexes can be rationalized on the basis of strong tetrahedral ligand field metal complexes.…”

Section: Introductionmentioning

confidence: 99%

“…The synthesis of stable homoleptic butadiene metal complexes is more challenging because of the tendency of butadiene to dimerize or trimerize on a transition metal site. However, the zerovalent cobalt 1,4-bis(trimethylsilyl)butadiene derivative [(Me 3 Si) 2 C 4 H 4 ] 2 Co was synthesized and structurally characterized in 1996 . In this system the bulky trimethylsilyl substituents inhibit butadiene dimerization or trimerization.…”

Section: Introductionmentioning

confidence: 99%

Tris(butadiene) Metal Complexes of the First-Row Transition Metals versus Coupling of Butadiene to Eight- and Twelve-Carbon Hydrocarbon Chains

Fan

et al. 2019

J. Phys. Chem. A

View full text Add to dashboard Cite

The role that zerovalent nickel plays in catalyzing the trimerization of butadiene to 1,5,9-cyclododecatriene conveys interest in the properties of the tris(butadiene)metal complexes (C4H6)3M. In this connection the complexes (C4H6)3M (M = Ti–Ni) of the first-row transition metals have been investigated by density functional theory. The intermediate C12H18Ni which has been isolated in the nickel-catalyzed trimerization of butadiene but is too unstable for X-ray crystallography is suggested here to have an open-chain hexahapto η3,3-C12H18 ligand rather than the octahapto such ligand suggested by some investigators. The lowest energy (C4H6)3M structures of the other first-row transition metals from vanadium to cobalt are found to have related structures with open-chain C12H18 ligands having hapticities ranging from four to eight with hexahapto structures being most common. The nickel and cobalt (C12H18)M derivatives favor low-spin singlet and doublet spin states, respectively, whereas the manganese derivative (C12H18)Mn favors the high-spin sextet state corresponding to the half-filled d5 shell of Mn(II). A (C4H6)3Cr structure with three separate tetrahapto butadiene ligands analogous to the very stable (η4-C4H6)3M (M = Mo, W) with the favored 18-electron metal configuration is found to be a very high energy structure relative to isomers containing an open-chain C12H18 ligand.

show abstract

Mass Spectrometry of Organocobalt Derivatives

Koszinowski

2022

Patai's Chemistry of Functional Groups

View full text Add to dashboard Cite

Being one of the most powerful and versatile analytical techniques, mass spectrometry has greatly contributed to the analysis of organocobalt derivatives. After a short discussion of the ionization methods most relevant to the investigation of these species, this chapter reviews the application of mass spectrometry to the analysis of the title compounds. First, these applications include the characterization of preformed organocobalt derivatives, such as cobalt complexes with σ‐bound organyl groups, cobalt complexes with organic π‐donor ligands, and carbonyl‐containing cobalt clusters. In these cases, mass spectrometry is typically used as a routine technique, together with additional analytical methods. Second, mass spectrometry, particularly its electrospray‐ionization (ESI) variant, can also be employed for the detection and identification of in situ formed organocobalt derivatives. While ESI mass spectrometry is limited to the analysis of charged species, this method has succeeded in the observation of several quasi‐neutral organocobalt intermediates bearing a charged tag. From the time profiles of the ESI signal intensities of these intermediates, valuable information on the reaction kinectics could also be obtained. Finally, mass spectrometry has been extensively applied to the gas‐phase preparation and analysis of organocobalt derivatives. In the highly diluted gas phase, even very reactive organocobalt ions can be generated and further examined. Tandem‐spectrometry permits the mass selection of these ions and thereby greatly facilitates their analysis. Thus, gas‐phase experiments probing the uni‐ and bimolecular reactivity of organocobalt ions have afforded seminal thermochemical and mechanistic information. Coupling tandem mass spectrometry with gas‐phase spectroscopy has moreover furnished insight into the structures of organocobalt ions.

show abstract

Bis{1, 4-bis(trimethylsilyl) buta-1, 3-diene} cobalt: synthesis and molecular structure

Cited by 4 publications

References 16 publications

Tris(Butadiene) Compounds versus Butadiene Oligomerization in Second-Row Transition Metal Chemistry: Effects of Increased Ligand Fields

Tris(Butadiene) Compounds versus Butadiene Oligomerization in Second-Row Transition Metal Chemistry: Effects of Increased Ligand Fields

Tris(butadiene) Metal Complexes of the First-Row Transition Metals versus Coupling of Butadiene to Eight- and Twelve-Carbon Hydrocarbon Chains

Mass Spectrometry of Organocobalt Derivatives

Contact Info

Product

Resources

About