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6850023 
Journal Article 
Aluminium bromide ether adducts: Structures in solution and in the solid state 
Jakobsmeier, L; Jakobsmeier, L; Krossing, I; Krossing, I; Noth, H; Noth, H; Schmidt, MJH; Schmidt, MJH 
1996 
1 
Zeitschrift für Naturforschung. Teil B, Chemie, Biochemie, Biophysik, Biologie und verwandte Gebiete
ISSN: 0044-3174 
51 
8 
1117-1126 
Monoglyme forms a molecular 1:1 adduct with AlBr3 which dissociates into the ions AlBr2(DME)(2)(+) and AlBr4- in DME, CH2Br2 and CDCl3 as solvents. A hexacoordinated Al center is present in the solid adduct AlBr3 . diglyme. The oxygen and bromine atoms are arranged in a meriodional configuration as shown by X-ray crystallography. However, in solution dissociation occurs into AlBr2(diglym)(2)(+) and AlBr4-. Not unexpectedly, AlBr3 forms the adduct AlBr3 . 2THF with tetrahydrofuran. The dioxane adduct AlBr3 . diox is polymeric in the solid state and has a chain structure with pentacoordinated trigonal-bipyramidal Al centers. The Br atoms are arranged in a slightly distorted trigonal plane. In solution, the presence of tetracoordinated Al is indicated by Al NMR spectroscopy. AlBr3 cleaves one of the C-O bonds of 12-crown-4 leading to the dimer of omega-bromo-tetra(ethyleneoxy)aluminium dibromide. This dimer contains pentacoordinated Al centers as proven by X-ray structure analysis. In contrast, the adduct of AlBr3 with 15-crown-5 is most likely an ionic compound, and is best described as [AlBr2(15-crown-5)]AlBr4 based on Al-27 NMR and IR data.< 
aluminiumtribromide-monoglyme; aluminiumtribromide-diglyme; aluminiumtribromide-1; 4-dioxane; omega-bromo-tetra(ethylenoxo)-aluminiumdibromide dimer; (15-crown-5)aluminium dibromide tetrabromoaluminate