Publications by authors named "Zdirad Zak"

Synthesis and characterization of two novel copper β-diketone complexes, where halogen bonds play a pivotal role in shaping their multifaceted structural landscape, have been done in the present study. This study employs X-ray diffraction, ultraviolet-visible (UV-vis) spectroscopy, and infrared (IR) spectroscopy to investigate two copper β-diketone complexes, [Cu(L1)(ttfa)]·2CHOH () and [Cu(L1)(dfpb)] (), where Httfa is 4,4,4-trifluoro-1-(thiophen-2-yl)butan-3,1-dione and Hdfpb is 4,4-difluoro-1-phenylbutane-1,3-dione. Complex displays a halogen bond, which contributes to its uniqueness.

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The reaction of (SeO3)4 with 1,4-dioxane (diox, dioxane) with or without diluting solvent led to the isolation of the unprecedented esters of selenic acid-1,2-ethyl selenate (CH2O)2SeO2 and the glyoxal diselenate O2Se[(OCHO)2]SeO2. It was possible to isolate an unknown dimeric form of Se2O5 (Se4O10·(diox)2) and a geometrical isomer of the mixed-valence oxide trans-Se3O7, both stabilized by dioxane. The dioxane adduct of monomeric selenium trioxide SeO3·diox was obtained from the reaction of (SeO3)4 with dioxane in liquid SO2.

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Two novel heterometallic complexes [Cd(NH3)6][{VO(O2)2(OH)}2{μ-Cd(NH3)4}] (2) and [{VO(O2)2(Im)}2{μ-Cu(Im)4}] (3) (Im = imidazole) containing peroxidovanadium complexes as metalloligands were prepared and characterized by spectral methods. X-ray single-crystal analysis revealed the presence of unique trinuclear complexes in the crystal structures of 2 and 3. The structure of 2 contains an anionic complex, whose two {VO(O2)2(OH)}(2-) ions are interconnected by a {μ-Cd(NH3)4}(2+) group.

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The first dinuclear nonperoxido tartrato complexes of vanadium(V), (NMe(4))(2)[V(2)O(4)((2R,3R)-H(2)tart)(2)] x 6 H(2)O (1), (NMe(4))(2)[V(2)O(2)((2R,3R)-tart)((2S,3S)-tart)] (2), (NEt(4))(2)[V(2)O(2)((2R,3R)-tart)((2S,3S)-tart)] (3) (tart = tartrato(4-) = C(4)H(2)O(6)(4-)) have been prepared from water-ethanol medium and characterized by X-ray structure analysis and spectral methods. The formation of the complexes has been found to be stereospecific; the composition and structure of anions containing one or both enantiomers of the ligand are profoundly different. The structure of anions in 1-3 also differs significantly from the structure of other dinuclear vanadium(V) alpha-hydroxycarboxylato complexes, but, interestingly, the geometry of the [V(2)O(2)((2R,3R)-tart)((2S,3S)-tart)](2-) ion resembles the structure of the [(VO)(2)((2R,3R)-tart)((2S,3S)-tart)](4-) ion which has a vanadium(IV) center.

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Crystals of the title compound, NaScP(2)O(7), were grown by a flux method. The crystal structure is isotypic with those of α-NaTiP(2)O(7), NaYbP(2)O(7) and NaLuP(2)O(7), and is closely related to that of NaYP(2)O(7). The structural set-up consists of a three-dimensional framework of P(2)O(7) units that are corner-shared by ScO(6) octa-hedra, forming tunnels running parallel to [010].

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The structure of the title compound, (C(6)H(7)N(2)O)(6)[V(10)O(28)].2H2O, at 120 (2) K has monoclinic (C2/c) symmetry. The asymmetric unit consists of one half-decavanadate anion of Ci symmetry, three cations and one water molecule.

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A study of the aqueous H3O+(OH-)/H2VO4-/(2R,3R)-tartrate system has been performed at 273 K in a 1.0 mol/L Na+(Cl-) ionic medium using 51V NMR spectroscopy. In this relatively complicated system, more than 12 different species were observed.

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Procedure of the synthesis is described for new platinum(IV) drug LA-12 [(OC-6-43)-bis(acetato)(1-adamantylamine)amminedichloroplatinum(IV)]. The X-ray diffraction analysis shows that the structure is created by molecules with octahedral arrangement of ligands around a platinum atom and contains one H(2)O molecule that is not a part of the coordination sphere of platinum. This new drug is more reactive with glutathione than cisplatin and is lacking cross-resistance with cisplatin as proven on the panel of cancer cell lines.

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Bis(methylsulfonamido) sulfone, C(2)H(8)N(2)O(6)S(3) or SO(2)(NHSO(2)CH(3))(2), was synthesized from imidobis(sulfonyl chloride), HN(SO(2)Cl)(2), and bis(trimethylsilyl)methane, CH(2)[Si(CH(3))(3)](2), in chlorotrimethylsilane solution. In the solid state, there are two independent molecules linked by two N-H..

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An ionic form of diphenyltrichlorophosphorane, namely, diphenyldichlorophosphonium trichloride isolated as a dichlorine solvate (1), was obtained by treating PPh(2)Cl(3) with excess chlorine. The identity of this species was established by single-crystal X-ray analysis and (31)P, (1)H, and (35)Cl NMR and Raman spectra. Bis(diphenyldichlorophosphonium) pentachloroindate (2) was obtained by the reaction of diphenyltrichlorophosphorane with indium trichloride in dichloromethane for comparison purposes.

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