First Metal Complexes of the Norcaradiene Form of 1,6‐Methano[10]annulene

Mues, Peter; Benn, Reinhard; Tsay, Yi‐Hung; Vogel, Emanuel; Wilke, Günther

doi:10.1002/anie.198208681

Cited by 8 publications

(1 citation statement)

References 11 publications

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“…These compounds are the starting materials for the preparation of 7-11,13, 14,22,23,26-29, 33, 36,37,40,41, 43, and 44 which are obtained by the appropriate replacement reactions.16 The preparation of 10 and 1117 as well as 9,22,33,36, and 4114 The complexes 34,35,38,and 39 with substituents at the i;4-bonded cyclohexadiene were obtained by treating the corresponding bis(ethylene)cobalt complexes with substituted acetylenes.15 Details of the preparation of these compounds as well as of the replacement products with indenyl and substituted cyclopentadienyl ligands and their full characterization by mass, 4H NMR, and 13C NMR spectroscopy are given in the Ph.D. Thesis of K. Cibura.15 45 was obtained from Li-(tmeda)2Co(C2H4)4,14 cycloheptatriene, and Me3SiCl.15 The preparation of 42 has been reported recently. 21 NMR Spectra. NMR spectra have been recorded on a WH 400 Bruker spectrometer equipped with a fast pulse programmer.…”

Section: Methodsmentioning

confidence: 99%

Cobalt-59 NMR spectroscopy of organocobalt(I) and -cobalt(III) compounds and its relation to chemical properties of the complexes

Benn¹,

Cibura²,

Hofmann³

et al. 1985

Organometallics

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59Co NMR parameters of various organocobalt(I) and -cobalt(III) complexes with ir-ligands have been determined in solution in order to find out whether they provide a measure for complex properties. The 59Co shifts of (?)1 23-allyl) (^-cyclopentadienyl)ComR complexes (R = Br, benzyl, methyl) range from 1100 to -1300 ppm. (r)3-Allyl)3Co ( 1) and (tj3-2-methylallyl)3Co (2) yield 59Co signals close to the region typical for organocobalt(I) compounds. Even at -50 and -30 °C the line width of their resonances is relatively narrow (3750 and 13000 Hz, respectively). In (olefinLCo^complexes 5("Co) is sensitive to the type of R ligand and increases in the series alkyl-substituted-j/1-cyclopentadienyl, ^-cyclopentadienyl, r)6-indenyl, and 7j3-allyl. In the (^-cyclopentadienyl)Co^series, <5("Co) increases within the sequence L = cyclobutadiene, (CO)2, jj4-cyclohexadiene, ?;4 *-butadiene, ij4-cyclopentadiene, and (ethylene)2. These orderings resemble the strength of complexation of the ir-ligand. Extended Hiickel molecular orbital calculations were performed to compare (cyclopentadienyl)cobalt dicarbonyl and (cyclopentadienyl)cobalt bis(ethylene) with respect to their HOMO/LUMO gap and their frontier MO composition, in order to probe the influence of different paramagnetic screening terms upon "Co shifts in these complexes. The increased shielding of the Co nucleus in the dicarbonyl complex can be rationalized by its 0.3-eV larger HOMO/LUMO energy separation and its smaller Co contribution in the LUMO wave function. Chemical applications and the relevance of "Co NMR data are pointed out. Additionally, structures and dynamic behavior of these complexes have been investigated by !H and 13 *C NMR spectroscopy.

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Section: Methodsmentioning

confidence: 99%

Cobalt-59 NMR spectroscopy of organocobalt(I) and -cobalt(III) compounds and its relation to chemical properties of the complexes

Benn¹,

Cibura²,

Hofmann³

et al. 1985

Organometallics

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[4.4.1]Propellatetraene and Related Propellanes

Frauenrath

Kapon

Rubin

1989

Israel Journal of Chemistry

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Reaction of dichlorovinylene carbonate with 1,6-methano[l O]annulene (2) followed by hydrolysis ofthe intermediate adduct afforded n-diketone 3. Photolysis of3 at liquid' nitrogen temperature yielded the title compound, 1. The activation parameters for the thermal isomerization 1 -+ 2 were W'" = 5.1 kcal/mole and /is''' = -19 eu (100 K). The structure of 3 was established by X-ray analysis. This analysis and MM2 calculations on a number of related compounds provide additional examples of the so-called "Klammer" effect in propellanes.

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Cobalt, rhodium and iridium

Mague¹

1984

Journal of Organometallic Chemistry

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First Metal Complexes of the Norcaradiene Form of 1,6‐Methano[10]annulene

Abstract: could be explained in terms of a temperature-dependent equilibrium between 2d and the open form 2a. Evidence for such an equilibrium is provided by the IR spectra recorded in solution at high temperatures.

Cited by 8 publications

References 11 publications

Cobalt-59 NMR spectroscopy of organocobalt(I) and -cobalt(III) compounds and its relation to chemical properties of the complexes

Cobalt-59 NMR spectroscopy of organocobalt(I) and -cobalt(III) compounds and its relation to chemical properties of the complexes

[4.4.1]Propellatetraene and Related Propellanes

Cobalt, rhodium and iridium

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