58451-82-4Relevant academic research and scientific papers
Synthesis, molecular structure, and spectral analysis of copper(II) complexes derived from pyridinediols
Chans, Guillermo M.,Gómez, Elizabeth,Gómez-Vidales, Virginia,Toscano, R. Alfredo,álvarez-Toledano, Cecilio
, p. 206 - 219 (2015)
A series of mononuclear copper(II) complexes was synthesized by reaction of different 2,6-disubstituted pyridines with elemental Cu in a CCl4/DMSO solvent system. Physical properties were analyzed using IR, optical spectroscopy, mass spectromet
Controlling Nuclearity and Stereochemistry in Vanadyl(V) and Mixed Valent VIV/VV Complexes of Oxido-Pincer Pyridine-2,6-dimethanol Ligands
Nitsche, Sara,Schmitz, Simon,Stirnat, Kathrin,Sandleben, Aaron,Klein, Axel
, p. 1805 - 1815 (2018)
The coordination chemistry of three oxido-pincer ligands 2,6-(HOCR2)2(pyridine) (H2L) based on 2,6-pyridinedimethanol [R = H (H2pydim), Me (H2pydip), Ph (H2pyphen)] towards vanadium(V) was explored. Reaction of NH4VO3 with the protoligands H2L gave the dinuclear complexes [(L)OV(μ-O)VO(L)]. Mononuclear anionic species [VO2(L)]–, which were isolated as alkaline metal salts were obtained from reactions of [VO(acac)2] (acac– = acetylacetonate) and H2L under basic conditions and addition of HCl to these species allowed to isolate the unprecedented oxido chlorido complexes [VOCl(L)] for pydip and pyphen. Cyclic voltammograms of the dinuclear [V2O3(L)2] and mononuclear [VOCl(L)] complexes show reversible VV/VIV reduction waves, while corresponding waves of the anionic [VO2(L)]– are completely irreversible. The mixed-valent VIV/VV species [V2O3(L)2]·– were characterized by EPR and UV/Vis spectroelectrochemistry revealing a delocalized system with a 15 line EPR spectrum and an intervalence charge transfer (IVCT) band for the bulky pyphen ligand but localized radicals in case of the pydim and pydip derivatives (8 line EPR, no IVCT). DFT calculated structures of the three derivatives show an V–O–V arrangement for [V2O3(pyphen)2]·– of about 145° ideally suited for delocalization, whereas for [V2O3(pydip)2]·– an angle of 128° was found.
Cis-2,6-Bis-(methanolate)-piperidine oxovanadium(V) complexes as catalysts for oxidative alkenol cyclization by tert-butyl hydroperoxide
D?nges, Maike,Amberg, Matthias,Stapf, Georg,Kelm, Harald,Bergstr??er, Uwe,Hartung, Jens
, p. 120 - 134 (2014/07/08)
cis-2,6-Bis-(methanolate)-piperidine oxovanadium(V) complexes are Lewis acids able to catalyze oxidative cyclization of alkenols by tert-butyl hydroperoxide (TBHP). Terminal dimethyl-substituted (prenyl-type) 4-pentenols bearing an alkyl or a phenyl group in position 1 afford under such conditions 2,5-cis-derivatives of 2-(tetrahydrofuran-2-yl)-2-propanol as major and tetrahydropyran-3-ols as minor products (four examples). Oxidizing 1-phenyl-6-methylhept-5-en-1-ol yields a 75/25-mixture of the derived 2-(tetrahydropyran-2-yl)-2-propanol and an oxepan-3-ol, whereas 2-propenols give epoxides in up to 94% yield. Epoxidizing geraniol by TBHP in the presence of a vanadium catalyst prepared from (2S,6R)-2-diphenylmethanol-6- hydroxymethylpiperidine occurs enantioselectively. Highfield shifts of vanadium-51 resonances upon adding alkyl hydroperoxides to solutions of cis-2,6-bis-(methanolate)-piperidine vanadium(V) complexes point to vanadium(V) tert-butyl peroxy complex formation as key step for activating peroxides.
Titanium(4+) and zirconium(4+) dichloride complexes with pyridinedicarboxylic acid derivatives as ethylene polymerization catalysts
Smirnova,Sukhova,Solov'Ev,Galibeev,Gagieva, S. Ch.,Tuskaev,Bulychev
experimental part, p. 555 - 557 (2011/07/30)
Titanium(4+) and zirconium(4+) complexes with pyridinedicarboxylic acid derivatives have been synthesized. The composition and structure of the synthesized 2,6-bis(diphenylhydroxymethyl)pyridine complexes have been corroborated by NMR and IR spectroscopy,
Dimethyltin(IV) 2,6-disubstituted pyridine complexes
Gómez, Elizabeth,Flores, Rosario,Huerta, Gloria,Alvarez-Toledano, Cecilio,Toscano, Rubén,Santes, Vítor,Nava, Noel,Sharma, Pankaj
, p. 115 - 122 (2007/10/03)
The synthesis and characterization of hypervalent pentacoordinated dimethyltin complexes obtained from the reaction of 2,6-disubstituted pyridine ligands with dichlorodimethyltin are reported. The complexes were characterized by mass spectrometry, 1
