Notizen: Über Aromaten-metall-komplexe von Metallen LXIV

Access to the Bis‐benzene Cobalt(I) Sandwich Cation and its Derivatives: Synthons for a “Naked” Cobalt(I) Source?

“…Separate determination of the spin and orbital magnetic moments of 1 + (g) , as possible by XMCD, reveals a non‐vanishing orbital contribution to μ eff of 0.2 μ B . Thus, the values obtained for 1 + (g) and 1 + / 2 + [A] − are within the range of previously reported values for the isoelectronic d 8 complexes Co(hmb) 2 + (magnetic balance (MB): 2.95, SQUID: 2.6–2.8), Ni(hmb) 2 2+ (MB: 3.00) and Fe(hmb) 2 0 (MB: 3.08 μ B ) and are in good agreement with the expected triplet state. The detected orbital magnetic moment of the cation 1 + (g) indicates spin‐orbit coupling and is in line with the observation of a zero‐field splitting (ZFS) in the samples of 1 + / 2 + [A] − .…”

Reaction of ferrocene with polyaromatic molecules. .pi.-Arenebis(.pi.-cyclopentadienyliron) dications. II. Electronic structure

“…Most chemicals either were reagent grade or were purchased from commercial sources. Biferrocene was prepared as reported,24 phenylmesitylene was prepared by the standard diazotization method, and [Fe(HMBZ)2](PF6)2 was prepared as per Fischer, et al 25 Physical Measurements. Electronic absorption spectra were recorded in Spectro-Grade acetonitrile with a Cary 14 spectrophotometer.…”

Synthesis and characterization of the unusual cluster [Ni2(GaAr′)2(η1:η1-μ2-C2H4)]: Ready addition of ethylene to Ni(COD)(GaAr′)2 at 25 °C and 1 atmosphere

“…In addition, the first example of a metal complex of a neutral arene, bis(benzene)chromium, [Cr(h 6 -C 6 H 6 ) 2 ], was reported four years later by Fischer and Hafner [2]. Since that time, ionic and neutral metallocenes and bis (arenes) [3,4], including ansa-bridged and half-sandwich type complexes have been studied intensively by experimental and theoretical investigations [5e8]. Recent examples of interesting metal complexes stabilized by pearene interactions include the first organometallic zinc(I) compound, [(h 5 -C 5 Me 5 )ZneZn(h 5 -C 5 Me 5 )] [9] containing the first stable ZneZn bond in a molecular complex, the sandwich complexes containing monolayer palladium sheets, [Pd 3 (C 7 H 7 )Cl 3 ] þ and [Pd 5 (naphthanacene) 2 (toluene)] þ [10], the mixed-valent [Fe(0)(NHC)(p 8 -h 4 ,h 4 -COT)Fe(I)(p 6 -h 5 -COT) 2 ] 2 species and the tri-iron cluster Fe 3 (COT) 3 (COT ¼ 1,3,5,7-cyclooctatetraene), which was obtained by the fusion of three molecules of Fe(COT) catalyzed by N-heterocyclic carbenes (NHC) [11].…”