ISSN:
0044-2313
Keywords:
Zinc complexes
;
imidazole
;
imidazoline
;
bisimidazoline complexes
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Description / Table of Contents:
Zinc Coordination Compounds with Imidazoline and Imidazole Donor Ligands.By reaction of the two bidentate bisimidazoline ligands 1,2-bis(2-imidazoline-2-yl)ethan (BIE) and 1,2-bis(2-imidazoline-2-yl)benzene (BIB) with zinc bromide under various reaction conditions the complexes [ZnBr2(BIE)] (1), [ZnBr2(BIB)] (2), [Zn(BIE)2]Br2 (3) and [Zn(BIB)2](BPh4)2 (4) were synthesized and characterized. In all compounds the zinc atom is tetrahedrally coordinated, either by a bidentate ligand and two bromine ligands, or by two of the chelate ligands. Zn—N—bond distances for 1-4 range from 1.966(2) to 2.013(3) Å, and the Zn—Br distances from 2.372(1) to 2.403(1) Å. [3-(imidazole-1-yl)-1-oxopropyl]benzene (IOB) was prepared as a novel imidazole ligand which carries a keto-O atom in 1,5-position to the pyridine-N atom. The zinc in [ZnCl2(IOB)2] (5) is coordinated by two ligands and two Cl atoms forming a distorted tetrahedral ZnN2Cl2 unit (Zn—N: 2.013(3) and 2.029(2) Å; Zn—Cl: 2.226(1) and 2.242(1) Å).The colourless compounds 1-5 were characterized by IR, 1H-NMR, X-ray absorption spectra and single-crystal X-ray structure analysis. Space groups and structural data: 1: P21/c, a = 7.717(2), b = 22.814(5), c = 8.026(2) Å, β = 117.58(2)° (140 K), R = 0.0283; 2: Cc, a = 11.831(3), b = 11.677(1), c = 11.846(1) Å, β = 114.55(2)°, R = 0.0237; 3: P42/n, a = 7.931(1), c = 16.945(1) Å, R = 0.0312; 4: P21/c, a = 18.666(2), b = 16.615(2), c = 19.786(2) Å, β = 99.17(1)°, R = 0.0472; 5: P21/c, a = 9.173(2), b = 9.230(1), c = 28.357(3) Å, β = 96.63(1)°, R = 0.0317.
Notes:
Durch Umsetzungen der zweizähnigen Bisimidazolin-Liganden 1,2-Bis(2-imidazolin-2-yl)ethan (BIE) und 1,2-Bis(2-imidazolin-2-yl)benzol (BIB) mit Zinkbromid unter verschiedenen Reaktionsbedingungen konnten die Komplexverbindungen [ZnBr2(BIE)] (1), [ZnBr2(BIB)] (2), [Zn(BIE)2]Br2 (3) und [Zn(BIB)2](BPh4)2 (4) synthetisiert und charakterisiert werden. Das Zinkatom ist jeweils tetraedrisch von einem zweizähnigen Chelatliganden und zwei Bromatomen oder von zwei dieser Liganden koordiniert. Die Zn—N-Bindungslängen in 1-4 variieren zwischen 1,966(2) und 2,013(3) Å, für die Zn—Br-Abstände wurden Werte zwischen 2,372(1) und 2,403(1) Å beobachtet. Mit dem neuen Liganden [3-(Imidazol-1-yl)-1-oxopropyl]benzol (IOB) gelang die Synthese des Komplexes [ZnCl2(IOB)2] (5), in dem eine tetraedrische ZnN2Cl2-Koordinationseinheit vorliegt (Zn—N: 2,013(3) und 2,029(2) Å; Zn—Cl: 2,226(1) und 2,242(1) Å).Die farblosen Verbindungen 1-5 wurden durch IR-, 1H-NMR- und Röntgenabsorptionsspektren sowie durch vollständige Röntgenstrukturanalysen charakterisiert. Raumgruppen und Gitterkonstanten: 1: P21/c, a = 7,717(2), b = 22,814(5), c = 8,026(2) Å, β = 117,58(2)° (140 K), R = 0,0283; 2: Cc, a = 11,831(3), b = 11,677(1), c = 11,846(1) Å, β = 114,55(2)°, R = 0,0237; 3: P42/n, a = 7,931(1), c = 16,945(1) Å, R = 0,0312; 4: P21/c, a = 18,666(2), b = 16,615(2), c = 19,786(2) Å, β = 99,17(1)°, R = 0,0472; 5: P21/c, a = 9,173(2), b = 9,230(1), c = 28,357(3) Å, β = 96,63(1)°, R = 0,0317.
Additional Material:
8 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/zaac.19936190707
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