Metallatomsynthese, Eigenschaften und Struktur von μ 2 ‐(η 3 ,η 3 ‐Toluol)bis[(η 6 ‐toluol)eisen](Fe‐Fe)
1995; Wiley; Volume: 128; Issue: 9 Linguagem: Inglês
10.1002/cber.19951280915
ISSN0009-2940
AutoresJöurg J. Schneider, Ullrich Specht, Richard Goddard, Carl Krüger, Jürgen Ensling, Philipp Gütlich,
Tópico(s)Coordination Chemistry and Organometallics
ResumoMetal Atom Synthesis, Properties, and Structure of μ 2 (η 3 ,η 3 ‐Toluene)bis[(η 6 ‐toluene)iron](Fe‐Fe) Metal atom cocondensation of iron atoms and toluene produces the mononuclear iron sandwich compound [(η 6 ‐toluene)(η 4 ‐toluene)Fe] 1 . Complex 1 reacts with a palette of N ‐containing ligands such as primary, secondary, and tertiary amines as well as pyridine, pyrrolidine, and tmeda to form highly reactive instable intermediates. In the temperature range from ‐80 to ‐30°C, the proposed intermediates react with toluene to form the first homoleptic Fe/toluene complex μ 2 ‐(η 3 η 3 ‐toluene)‐bis[(η 6 ‐toluene)iron](Fe‐Fe) ( 3 ) regardless which N ‐containing ligand is used. Additionally, 3 is also formed when ethanol is used instead of N ‐containing base ligands. Black thermolabile 3 was characterized by low‐temperature 1 H‐, 13 C‐, and Möβbauer spectroscopy as well as by an X‐ray structure analysis (‐173°C). The X‐ray structure determination reveals a μ‐η 3 η 3 ‐briding toluene ligand capping two {(η 6 ‐toluene)Fe} units which are connected by an Fe‐Fe bond [2.746(1) Å]. However, in solution up to ‐30°C all three toluene ligands are fluxional according to 1 H‐ and 13 C‐NMR data. At ‐10°C 3 reacts with CO with decomposition to form Fe metal. With 2,2‐bipyridine and ethene no reaction is observed up to room temperature.
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