In: Chemical Communications, 2005, vol. (33), p. 4155
Two diastereoisomers of tetranuclear cyclometallated iridium complexes, either having an inner core of HEXOL-type [Ir(IrCl₂)₃]⁶⁺ unit and a surface of six chiral, didentate, cyclometallated ligands, are stereoselectively synthesized from an enantiopure pinenopyridine derivative.
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Thèse de doctorat : Université de Fribourg, 2001 ; no 1332.
The first objective of this thesis is the calculation of excited state energies and properties of transition metal complexes using Density Functional Theory (DFT). To explore this wide topic, we did choose three different chemical systems. The first one, presented in the chapter 4, is about the photodissociation of the tris(2,2’- bipyridine)ruthenium(II) ([Ru(bpy)3]2+) ion. Over the last two...
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In: Chemistry - A European Journal, 2005, vol. 11, p. 185-194
Detailed protonation experiments of the [5,6]-pinenebipyridine molecule and the unsubstituted [4,5]- and [5,6]-CHIRAGEN[0] ligands in various solvents indicate a variety of structures of the protonated species. UV-visible and NMR measurements (including ¹⁵N chemical shifts) show the transition from trans to cis conformation of [5,6]-pinenebipyridine upon protonation. The...
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In: Dalton Transactions, 2004, vol. 3, p. 402-406
The enantiomerically pure chiral tris-chelating ligand (+)-(7S,10R)-L(L) comprising three 4,5-pinenobipyridine subunits connected through a mesityl spacer has been synthesized. Complexes of L with RuII and FeII have been prepared and characterised. NMR spectroscopy indicates that...
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In: Angewandte Chemie International Edition, 2004, vol. 43 (34), p. 4482-4485
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In: Helvetica Chimica Acta, 2005, vol. 88(3), p. 496-506
A publication by Alexander P. Smirnoff in Helvetica Chimica Acta in 1920 [6] describes the first synthesis of a coordination species, i.e., of tris(propane-1,2-diamine-κN¹,κN²)platinum(4+) ([PtIV(pn)₃]⁴⁺), where it was shown that the configuration of a chiral center in the ligand can influence the configuration at the metal. The present investigation of...
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In: Chemistry - A European Journal, 2004, vol. 10(19), p. 4839-4845
The hexadentate, and ditopic ligand 2,5-bis([2,2']bipyridin-6-yl)pyrazine yields a chiral, tetrameric, square-shaped, self-assembled species upon complexation with Fe²⁺ ions. The racemate of this complex was resolved with antimonyl tatrate as the chiral auxiliary. The purity of the enantiomer was determined by NMR spectroscopy, by using a chiral, diamagnetic shift reagent, and by circular...
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In: Inorganica Chimica Acta, 2005, vol. 358(1), p. 41-49
A series of ligands, where two pinene-bipyridine moieties are either connected directly, or through a p-xylene bridge are investigated with respect to their complexation behaviour in solution. The bridged [5,6]-CHIRAGEN[p-xyl] ligands, which are substituted in 5' or 6' positions show self-assembly reactions, which lead to similar supramolecular species as the unsubstituted bis-pinene-bipyridines...
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In: Polyhedron, 2004, vol. 23, no. 6, p. 1011-1017
The zinc(II) complexes 1aZnCl₂ and 1bZnCl₂ (1a: 2-(6',2''-bipyrid-2'-yl)-3-(2- pyridyl)pyrazine; 1b: 2-(6',2'-bipyrid-2'-yl)-5,6-dinitrilo-3-(2-pyridyl)pyrazine) were prepared by treatment of the ligands with ZnCl₂. The structures of both were investigated by X-ray crystallography and 1H NMR spectroscopy. Both complexes display proton deshielding phenomena that are attributed to a...
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Thèse de doctorat : Université de Fribourg, 2002 ; Nr. 1382.
In the scope of this thesis, enantiomerically pure 5’- and 6’-substituted pinene-fusedbipyridine- (pinene-bpy-derivatives) and N-pyridine ligands (pinene-N-py derivatives) have been prepared. The 6’-bromo-substituted pinene-bpy derivatives can act as precursors for the synthesis of several 6’-subsituted pinene-bpy derivatives. Tetradentate ligands have been prepared starting from these...
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