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: 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: Dalton Transactions, 2006, p. 1444 - 1454
A C₂-symmetric enantiopure 4,5-bis(pinene)-2,2′-bipyridine ligand (–)-L was used to investigate the diastereoselectivity in the formation of [ML₃]²⁺ coordination species (M = Fe(II), Ru(II), Os(II), Zn(II), Cd(II), Cu(II), Ni(II)), and [ML₂Cl₂] (M = Ru(II), Os(II)). The X-ray structures of the [ML₃]²⁺ complexes were determined for Δ-[FeL₃](PF₆)₂,...
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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: 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: New Journal of Chemistry, 2009, vol. 33, p. 462–465
Chiral bis-5,6-pinene bipyridine type ligands have been used to form, through self-assembly reaction, dinuclear coordination compounds which show a highly diastereoselective formation of double helices with copper(I) and silver(I) as coordination centers.
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In: The Journal of Organic Chemistry, 2006, vol. 71, no. 25, p. 9283 -9290
New polypyridylic chiral ligands, having either C₃ or lower symmetry, have been prepared via a de novo construction of the pyridine nucleus by means of Kröhnke methodology in the key step. The chiral moieties of these ligands originate from the monoterpen chiral pool, namely (-)-α-pinene ((-)-14, (-)-15) and (-)-myrtenal ((-)-9, (-)-10). Extension of the...
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In: Inorganic Chemistry, 2008, vol. 47, no. 18, p. 8016–8024
A new set of Ru−Cl complexes containing either the pinene[5,6]bpea ligand (L1) or the C₃ symmetric pinene[4,5]tpmOMe (L2) tridentate ligand in combination with the bidentate (B) 2,2′-bipyridine (bpy) or 1,2-diphenylphosphinoethane (dppe) with general formula [RuCl(L1 or L2)(B)]⁺ have been prepared and thoroughly characterized. In the solid state, X-ray diffraction...
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