215232-71-6Relevant academic research and scientific papers
Structure Investigations of Group 13 Derivatives of N-Phenylsalicylideneimine
Lewinski, Janusz,Zachara, Janusz,Starowieyski, Kazimierz B.,Ochal, Zbigniew,Justyniak, Iwona,Kopec, Tomasz,Stolarzewicz, Patryk,Dranka, Maciej
, p. 3773 - 3780 (2008/10/08)
The reaction of MMe3 with 1 molar equiv of N-phenylsalicylideneimine (HsaldPh) yields the O,N-chelate complexes Me 2M(saldPh) (where M = Al (1), Ga (2), In (3)) in high yields. The reaction of 1 with γ-picoline results in a ligand redistribution reaction and the formation of the five-coordinate complex MeAl(saldPh)2 (4), while the gallium and indium compounds are stable in the presence of γ-picoline. The resulting compounds have been characterized in a solution by NMR and IR spectroscopy and cryoscopic molecular weight measurements, and their molecular and crystal structure have been determined by X-ray crystallography. Compounds 1 and 2 exist as monomeric tetrahedral complexes, while the indium analogue 3 is dimeric with the In2(μ-O) 2 bridges and five-coordinate metal centers. The five-coordinate methylaluminum compound 4 exhibits trigonal-bipyramidal geometry of the metal center. The obtained results show that a Schiff base acts as a strongly coordinating chelate ligand and, in this regard, it resembles the symmetrical acetylacetonato ligand and related β-diketonates. An extended crystal structure analysis reveals that the isostructural crystalline complexes 1 and 2 comprise monomeric four-coordinate molecules linked by C-H imino...O hydrogen bonds, forming helical chains. Parallel left- and right-handed helices joined by C-H...π interactions give rise to the 3D extended tetragonal framework, with voids filled by solvent molecules. In the crystalline complex 4 the C-Haryl...O hydrogen bonds organize molecules into H-bonded dimers.
Four-coordinate dimethylgallium compounds vary in stability toward hydrolysis
Chesnut, Robert W.,Cesati III, Richard R.,Cutler, Cathy S.,Pluth, Sara L.,Katzenellenbogen, John A.
, p. 4889 - 4896 (2008/10/08)
Four-coordinate dimethylgallium complexes were prepared by the reaction of dimethylgallium hydroxide with bidentate Lewis bases and evaluated for their stability toward decomplexation in water, a key property in determining their potential usefulness as radiopharmaceuticals, particularly those targeted at specific receptor proteins. Model compounds from six structural classes, containing bidentate ligands with oxygen-oxygen, oxygen-nitrogen, and sulfur-nitrogen donor atoms, were prepared from the ligand and dimethylgallium hydroxide; they were characterized spectroscopically and, in two cases, by X-ray crystallography. The percentage decomplexation of the stable (CH3)2Ga+ unit from the Lewis base when exposed to 1000 equiv of water in acetone-d6, determined by 1H NMR, was used as a measure of the relative hydrolytic stability of each compound. Among the compounds we have investigated, the percent hydrolysis under these conditions ranged from 10% to 100%, the most hydrolytically stable compounds proving to be those based on an N-alkylsalicylaldimidate donor.
