ISSN:
0009-2940
Keywords:
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Description / Table of Contents:
Reaction of Arsinidene Complexes: Arsenic Atoms as Trigonally Planar Coordinated Bridging Elements within Trinuclear Metal ComplexesThe synthesis of compounds in which all five valence electrons of a μ3-bridging arsenic atom are involved in bonding to three metal ligand fragments is achieved for the first time by the reaction of arsinidene complexes ClAs[MLn]2 (MLn = Cr(CO)5, Mn(CO)2(η5-CH3C5H4)) with η5-C5H5(CO)3Ml′- (M′ = Mo, W); chlorine substitution and MM′ bond formation with accompanying loss of one carbonyl group leads to the complexes 3, (3a, M′ = Mo, MLn = Mn(CO)2(η5-CH3C5H4); 3b, M′ = Mo, MLn = Cr(CO)5; 3c, M′ = W, MLn = Cr(CO)5). In compounds 3 there is no lone pair left at the μ3-arsenic atom which therefore shows trigonal planar coordination. The electron deficiency at the arsenic atom is compensated for by metal-arsenic η-bonding in a manner similar to the bonding situation in arsinidene complexes. X-ray analyses for 3a-c confirm this statement.
Notes:
Die erstmalige Synthese von Verbindungen, in denen alle fünf Valenzelektronen eines μ3-verbrückenden Arsenatoms in die Bindung zu drei Metall-Ligand-Fragmenten einbezogen sind, gelingt durch Umsetzung von Arsiniden-Komplexen ClAs[MLn]2 (MLn = Cr(CO)5, Mn(CO)2(η5-CH3C5H4)) mit η5-C5H5(CO)3M′- (M′ = Mo, W). In den unter Substitution der Chlorfunktion und Ausbildung einer M′M-Bindung unter CO-Abspaltung entstandenen Komplexen 3, (3a, M′ = Mo, MLn = Mn(CO)2(η5-CH3C5H4); 3b, M′ = Mo, MLn = Cr(CO)5; 3c, M′ = W, MLn = Cr(CO)5) besitzt das Arsen kein freies Elektronenpaar mehr. Es ist daher trigonal planar koordiniert; sein Elektronendefizit wird, wie in Arsiniden-Komplexen, durch π-Bindungsanteile in den Metall-Arsen-Bindungen ausgeglichen. Röntgenstrukturanalysen für 3a-c belegen dies.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19821150604
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