ISSN:
0044-2313
Keywords:
Lithium(μ-hydrido)tri(alkyl)alanate
;
Li—H—Al bridge
;
Li … H—C interaction
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Description / Table of Contents:
Synthesis and Molecular Structure of (N,N′-Dimethyl-piperazine)lithium-(·-hydrido)(tert-butyl)bis[bis(trimethylsilyl)methyl]alanate with an Intramolecular Interaction between Lithium and C—H-σ-BondsSyntheses and properties of the starting compounds bis[bromo-di(tert-butyl)alane] 3, bis[dibromo-tert-butyl-alane] 4, and (tert-butyl)bis[bis(trimethylsilyl)methyl]alane 5 are described. In the presence of 5 and the chelating amine N,N′-dimethylpiperazine lithium tert-butyl gives via μ-elimination isobutene and LiH, which is taken up by the starting alane 5 to give the title compound 6. No attack of the strong base (lithium alkyl/amine) to the bis(trimethylsilyl) methyl substituent is observed as recently occured for the sterically more crowded tris[bis(trimethylsilyl)methyl]alane. Crystal structure of 6 shows a angled Li—H—Al bridge and a short intramolecular contact between Li and C—H-σ-bonds of a trimethylsilyl group.
Notes:
Synthese und Eigenschaften der zur Darstellung der Titelverbindung 6 benötigten Bis[brom-di(tert-butyl)alan] 3, Bis[dibrom-tert-butylalan]4 und (tert-Butyl)-bis[bis(trimethylsilyl)methyl]alan 5 werden beschrieben. Lithium-tert-butyl reagiert mit 5 in Gegenwart des Chelatbildners N,N′-Dimethylpiperazin unter β-Eliminierung zu Isobuten und Anlagerung des dabei gebildeten LiH an das Alan 5 zu dem Lithium-μ-hydridoalanat 6. Die Molekülstruktur zeigt im Festkörper eine gewinkelte Al—H—Li-Brücke und eine intramolekulare Wechselwirkung des Lithiumatoms zu C—H-σ-Bindungen einer Trimethylsilylgruppe.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/zaac.19915950122
