Derivate des Imidazols, VI. Stabile Carben‐Borane

Kühn, Norbert; Henkel, Gerald; Kratz, Thomas; Kreutzberg, Jörg; Boese, Roland; Maulitz, Andreas H.

doi:10.1002/cber.19931260913

Cited by 144 publications

(62 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…[33] The borane hydrogen atoms were located in the difference Fourier map. Thus, the tethered carbene group has also facilitated the isolation of the first stable, neutral borane adduct of an f-element cation.…”

Section: Resultsmentioning

confidence: 99%

Synthesis and Small Molecule Reactivity of Uranium(IV) Alkoxide Complexes with both Bound and Pendant N‐heterocyclic Carbene Ligands

Arnold

Blake

Wilson

2005

Chemistry A European J

View full text Add to dashboard Cite

The syntheses of two tetravalent uranium alkoxide-carbene complexes are reported, [UIL3], and [UL4] where L = OCMe2CH2[1-C(NCHCHNiPr)]. The latter shows dynamic behaviour of the alkoxycarbene ligands in solution at room temperature, and the crystal structure of [UL4] shows that one carbene group remains uncoordinated. The unbound N-heterocyclic carbene group is trapped by a range of reagents such as 16-valence-electron metal carbonyl fragments and BH3 moieties, forming, for example, [UL3(mu-L)W(CO)5], [UL2(mu-L)2Mo(CO)4], and [UL(n)(L-BH3)(4-n)] (n = 1-4), demonstrating the potential for these hemilabile electropositive metal-carbene complexes to participate in the bifunctional activation of small molecules.

show abstract

Section: Resultsmentioning

confidence: 99%

Synthesis and Small Molecule Reactivity of Uranium(IV) Alkoxide Complexes with both Bound and Pendant N‐heterocyclic Carbene Ligands

Arnold

Blake

Wilson

2005

Chemistry A European J

View full text Add to dashboard Cite

show abstract

“…Als starke Nucleophile [4] reagieren sie bereitwillig mit polaren Verbindungen der Hauptgruppenelemente, wobei in bezug auf das Zentralelement E sowohl Koordination (2, EX n = z. B. BH 3 [5], AlH 3 [6], SiCl 4 [7], GeI 2 [8], SnCl 2 , SnCl 4 [7], SCl 2 [9], SeI 2 [10] [24].…”

Section: Spectroscopic and Structural Data Indicate [Ph 2 (Carb)p]unclassified

Synthese und Eigenschaften von [Ph2(Carb)P]AlCl4 (Carb = 2,3-Dihydro-1,3-diisopropyl-4,5-dimethylimidazol-2-yliden) - ein stabiler Carben-Komplex des dreiwertigen Phosphors [1]

Kühn

Fahl

Bläser³

et al. 1999

Z. anorg. allg. Chem.

Self Cite

View full text Add to dashboard Cite

2,3‐Dihydro‐1,3‐diisopropyl‐4,5‐dimethylimidazol‐2‐yliden (7, Carb) reagiert mit Chlordiphenylphosphan zum kationischen Phosphan [Ph2(Carb)P]Cl (10), das mit AlCl3 in das stabilere Salz [Ph2(Carb)P]AlCl4 (13) überführt wird. Das kationische Phosphanselenid [Ph2(Carb)PSe]AlCl4 (14) wird aus 13 und Selen erhalten. Spektroskopische und strukturelle Daten weisen [Ph2(Carb)P]+ als kationisches Analogon von Ph3P aus. Die Kristallstruktur von 13 wird berichtet.

show abstract

“…Complexes 3-BH 3 [24] and a substituted analogue of 9-BH 3 which has ethyl substituents at the nitrogen atoms and methyl groups in the 4-and 5-positions of the imidazol-2-ylidene ring [25] are already known, but the bond strength has not been measured. Note that the calculations at the BP86/ TZVPP level predict that the CDP complex 3-BH 3 has a more weakly bonded ligand (D e = 32.9 kcal mol À1 ) than the parent system 1-BH 3 (D e = 40.5 kcal mol À1 ), while the MP2 and SCS-MP2 calculations suggest that the CDP-BH 3 bonds in the two complexes have similar BDEs.…”

mentioning

confidence: 99%

Divalent Carbon(0) Chemistry, Part 2: Protonation and Complexes with Main Group and Transition Metal Lewis Acids

Tonner

Frenking

2008

Chemistry A European J

298

124

View full text Add to dashboard Cite

Quantum-chemical calculations with DFT (BP86) and ab initio methods (MP2, SCS-MP2) were carried out for protonated and diprotonated compounds N-H(+) and N-(H(+))(2) and for the complexes N-BH(3), N-(BH(3))(2), N-CO(2), N-(CO(2))(2), N-W(CO)(5), N-Ni(CO)(3) and N-Ni(CO)(2) where N=C(PH(3))(2) (1), C(PMe(3))(2) (2), C(PPh(3))(2) (3), C(PPh(3))(CO) (4), C(CO)(2) (5), C(NHC(H))(2) (6), C(NHC(Me))(2) (7) (Me(2)N)(2)C==C==C(NMe(2))(2) (8) and NHC (9) (NHC(H)=N-heterocyclic carbene, NHC(Me)=N-substituted N-heterocyclic carbene). Compounds 1-4 and 6-9 are very strong electron donors, and this is manifested in calculated protonation energies that reach values of up to 300 kcal mol(-1) for 7 and in very high bond strengths of the donor-acceptor complexes. The electronic structure of the compounds was analyzed with charge- and energy-partitioning methods. The calculations show that the experimentally known compounds 2-5 and 8 chemically behave like molecules L(2)C which have two L-->C donor-acceptor bonds and a carbon atom with two electron lone pairs. The behavior is not directly obvious when the linear structures of carbon suboxide and tetraaminoallenes are considered. They only come to the fore on reaction with strong electron-pair acceptors. The calculations predict that single and double protonation of 5 and 8 take place at the central carbon atom, where the negative charge increases upon subsequent protonation. The hitherto experimentally unknown carbodicarbenes 6 and 7 are predicted to be even stronger Lewis bases than the carbodiphosphoranes 1-3.

show abstract

Derivate des Imidazols, VI. Stabile Carben‐Borane

Cited by 144 publications

References 45 publications

Synthesis and Small Molecule Reactivity of Uranium(IV) Alkoxide Complexes with both Bound and Pendant N‐heterocyclic Carbene Ligands

Synthesis and Small Molecule Reactivity of Uranium(IV) Alkoxide Complexes with both Bound and Pendant N‐heterocyclic Carbene Ligands

Synthese und Eigenschaften von [Ph2(Carb)P]AlCl4 (Carb = 2,3-Dihydro-1,3-diisopropyl-4,5-dimethylimidazol-2-yliden) - ein stabiler Carben-Komplex des dreiwertigen Phosphors [1]

Divalent Carbon(0) Chemistry, Part 2: Protonation and Complexes with Main Group and Transition Metal Lewis Acids

Contact Info

Product

Resources

About