7 research outputs found
Strukturne i elektronske osobine kompleksa nikal(II) sa pentadentatnim diaminotrikarboksilatnim ligandima
Helatori su grupa hemijskih jedinjenja koja poseduju dva ili viŔe donorskih atoma.
Imaju jedinstvenu osobinu helatacije (multikoordinacije metalnog jona) metalnih jona i atoma. EDTA (etilendiamin-tetrasirÄetna kiselina) i njegovi analozi nalaze znaÄajnu primenu kako u detoksifikaciji odreÄenih matrica životne sredine (vode pre svega) zagaÄenih jonima metala tako i u nuklearnoj medicini za proizvodnju odreÄenih kontrasta pri skeniranju tkiva magnetnom rezonancom. PolazeÄi od ovih Äinjenica mi smo za predmet ove disertacije predvideli sintezu nekih nedostajuÄih kompleksa nikla(II) kako bi smo kompletirali seriju jednostavnih diaminopolikarboksilnih helatnih kompleksa. Metodom rendgenostrukturne analize kao i analizom sintetisanih molekula na bazi savremene kompjuterske hemije sintetisana jedinjenja su sistematski karakterisana. Osnovni cilj bio je da se ispitaju uzroÄno-poslediÄne veze broja i distribucije petoÄlanih i Å”estoÄlanih helatnih prstenova u kompleksnom molekulu, njihove distribucije u kompleksu, stereohemije i elektronske konfiguracije. U ovoj disertaciji je sintetisano i karakterisano nekoliko razliÄitih tipova helata kao Å”to su: pentadentati diaminotrikarboksilatnog tipa (H3ed3a, H3ed3r, H3eda2r, H31,3-pd3a, H31,2-pd3a i H31,2-pd2ar); heksadentati diaminotetrakarboksilatnog tipa (H41,3-pd3ap).
NagraÄeni helati su iskoriÅ”Äeni za sintezu odgovarajuÄih kompleksa nikla(II). Na bazi rezultata rendgenske strukturne analize utvrÄeno je da su najstabilniji heksadentatni helati oni sa ravnomernim brojem petoÄlanih i Å”estoÄlanih helatnih prstenova. Korelacioni dijagram oktaedarskih devijacija uglova oko metalnog jona i tetraedarskih devijacija oko aminskih atoma azota upravo otkriva Äinjenicu da postoje kompromisne strukture (stabilni heksadentati) u seriji diaminotetrakarboksilatnih kompleksa dvovalentnih metala. Molekulsko orbitalna analiza ide u prilog ovoj tvrdnji, a Å”to se naroÄito može zakljuÄiti korelacijom energija prenosa naelektrisanja izmeÄu fragmenata (metal i edta-tip liganda) i broja petoÄlanih helatnih prstenova. Kao konaÄan zakljuÄak može se reÄi da nesimetriÄnost liganda (stvorena razliÄitim brojem ili veliÄinom karboksilnih grupa na atomima azota) prouzrokuje veÄu ili manju nestabilnost heksadentatnog helatnog kompleksa.Chelators are kind of chemical compounds with two or more donor atoms. They are having a uniqe property to chelate (multicoordination of metal ions) metal ions and atoms. EDTA (ethylenediaminetetraacetic acid) and its analogues are found as a detoxification agents of certain environmental matrix (it is water usually) polluted by metal ions and also as a markers for their use in early cancer discovering. Taking these facts into accounts the synthesis of several missing
nickel(II) complexes has been proposed for the main goal of this dissertation in order to make complete the whole set of the simple chelate diamintetracarboxylate complexes. An in-depth analysis has been carried out for all the prepared compounds paying particular attention to the results of X-ray diffraction analysis and modern quantum-mechanical modeling applied to prepared complexes. Basic goal of this work is to investigate causative-consequent realations of the number of five-membered and six-membered chelate rings in the molecule, their distribution
in the complex, stereochemistry and electron configurations. Here, several different kinds of chelates such as: pentadentates of diamintricarboxylate-type (H3ed3a, H3ed3Ń, H3edŠ°2Ń, H31,3-pd3a, H31,2-pd3a Šø H31,2-pd2aŃ); hexadentates of diamintetracarboxylate-type (H41,3-pd3ap)., have been prepared and characterized. The chelating agents have been used for preparation of corresponding nickel(II) complexes. On the basis of X-ray diffraction analysis it was established
that the most stable hexadenate chelates are those with equal distribution of five-membered and six-membered chelate rings. The correlation diagram between an octahedral angle deviation around metal ion and tetrahedral angle deviation around coordinated amine nitrogens reveals the fact that compromise structures (stable hexadentates) from whole set of divalent metal diamintetracarboxylate complexes exist. The results of molecular-orbital analysis further support such a claim particularly correlating charge transfer energies between fragments (metal and edtatype of ligand) and the number five-membered rings. As a final conclusion it might be stated that the chelate asymmetry (make by the different number or the size of carboxylate groups attached to amine nitrogens) cause more or less instability of the hexadentate chelate complexes
Supplementary data for article: RomanoviÄ, M. Ä.; ÄobeljiÄ, B.; Pevec, A.; Turel, I.; AnÄelkoviÄ, K.; MilenkoviÄ, M.; RadanoviÄ, D.; BeloÅ”eviÄ, S.; MilenkoviÄ, M. R. Synthesis, Crystal Structures and Antimicrobial Activity of Azido and Isocyanato Zn(II) Complexes with the Condensation Product of 2-Quinolinecarboxaldehyde and Girardās T Reagent. Journal of Coordination Chemistry 2017, 70 (14), 2425ā2435. https://doi.org/10.1080/00958972.2017.1343945
Supplementary material for: [https://doi.org/10.1080/00958972.2017.1343945]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/2493
First cobalt complexes with methyl pyruvate semi/thiosemicarbazone - synthesis, physico-chemical and structural characterization
In the reaction of acetone solutions of CoX2ānH2O (X = Cl, Br) with methyl pyruvate semi/thiosemicarbazone (Hmps, Hmpt) the first Co(II) complexes with these ligands, i.e., [Co(Hmps)(H2O)X2] (X = Cl (1), Br (2)), [Co(Hmpt)2][CoCl4]ā2H2Š (3) and [Co(Hmpt)2]Br2āMe2CO (4) were obtained. Complexes 1 and 2 represent the first examples of metal complexes of Hmps. All the obtained compounds were characterized by elemental analysis, conductometry, magnetic measurements, and IR spectra, and for complexes 2ā4, single crystal X-ray diffraction analysis was also performed. The effective magnetic moments were close to the upper limit (5 Ī¼B) for complexes 1 and 2, and close to the lower limit (4.4 Ī¼B) for complexes 3 and 4, and as such are characteristic for high-spin Co(II) complexes. Structural analysis showed that both ligands coordinate in a neutral form in a tridentate manner, via the ester oxygen, imine nitrogen and the oxygen atom of the ureido (Hmps), or the sulfur atom of the thioureido group (Hmpt). The central metal atoms are situated in a deformed octahedral coordination environment. Complex 2 has cis-Br configuration, while complexes 3 and 4 have mer-configuration
Supplementary material for the article: AnÄelkoviÄ, K.; MilenkoviÄ, M. R.; Pevec, A.; Turel, I.; MatiÄ, I. Z.; VujÄiÄ, M.; SladiÄ, D.; RadanoviÄ, D.; BraÄan, G.; BeloÅ”eviÄ, S.; et al. Synthesis, Characterization and Crystal Structures of Two Pentagonal-Bipyramidal Fe(III) Complexes with Dihydrazone of 2,6-Diacetylpyridine and Girardās T Reagent. Anticancer Properties of Various Metal Complexes of the Same Ligand. Journal of Inorganic Biochemistry 2017, 174, 137ā149. https://doi.org/10.1016/j.jinorgbio.2017.06.011
Supplementary material for: [https://doi.org/10.1016/j.jinorgbio.2017.06.011 ]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2495]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3258
Supplementary data for article: RomanoviÄ, M. Ä.; ÄobeljiÄ, B.; Pevec, A.; Turel, I.; AnÄelkoviÄ, K.; MilenkoviÄ, M.; RadanoviÄ, D.; BeloÅ”eviÄ, S.; MilenkoviÄ, M. R. Synthesis, Crystal Structures and Antimicrobial Activity of Azido and Isocyanato Zn(II) Complexes with the Condensation Product of 2-Quinolinecarboxaldehyde and Girardās T Reagent. Journal of Coordination Chemistry 2017, 70 (14), 2425ā2435. https://doi.org/10.1080/00958972.2017.1343945
Supplementary material for: [https://doi.org/10.1080/00958972.2017.1343945]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/2493