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New pentafluorobenzoate (Рfb) copper complexes with 2,3- and 3,5-lutidine (2,3- and 3,5-Lut, respectively), quinoline (Quin), and 1,10-phenanthroline (Рhen) ([Cu2(MeCN)2(Рfb)4] (I), [Cu(2,3-Lut)2(Pfb)2] (II), [Cu(3,5-Lut)4(Pfb)2] (III), [Cu(Quin)2(Pfb)2] (IV), and [Cu2(Phen)2(Pfb)4] (V)) are synthesized by the newly developed methods and characterized. The unusual heteroanionic pentafluorobenzoate benzoate (Вnz) ionic compound [Cu2(Рhen)2(Рfb)3]+(Рnz)– (VI) is synthesized. It is shown that the four-bridge binuclear metal cage of complex I is not retained in the reactions with various pyridine derivatives. In the case of such α-substituted pyridines as 2,3-lutidine and quinoline, the compositions and structures of the final products of the reactions with copper pentafluorobenzoate are independent of the initial ratio of the reagents and crystallization conditions. It is revealed by the Hirshfeld surface analysis that π···π, C–F···π, C–H···F, and F···F interactions make the major contribution to the stabilization of crystal packings of the synthesized complexes. [ABSTRACT FROM AUTHOR]

For the goal of preparing LiI–CrIII heterometallic coordination compounds, we studied the reaction of Cr(NO3)3·9H2O and Li2(cbdc) (obtained by the neutralization of LiOH·H2O and cyclobutane-1,1-dicarboxylic acid (H2cbdc)) interacting in the 1:3 ratio in aqueous and methanol solutions. It was found that synthesis in the aqueous medium and subsequent crystallization of the reaction solution results in a low yield (9%) of crystalline 2D polymeric compound {[CaLi6Cr4(OH)4(cbdc)8(H2O)16]·7H2O}n (1) formed due to the hydrolysis of a chromium(III) carboxylate complex and the introduction of Ca2+ ions penetrating into the structure as impurities in the initial LiOH·H2O compound. The use of methanol as a solvent in a similar reaction and subsequent long-term aging leads to the formation of crystals of [Li5Cr(cbdc)4(H2O)5]n (2, yield: 55%) whose 3D polymeric structure contains independent fragments with five Li+ ions and does not contain Ca2+ ions. The crystal structures of 1 and 2 are determined by single-crystal XRD (CCDC No. 2161744 (1), No. 2161745 (2)). [ABSTRACT FROM AUTHOR]

Strontium(II)—zinc(II) and strontium(II)—cadmium(II) coordination compounds with dianions of cyclobutane-1,1-dicarboxylic acid (H2cbdc) were synthesized. In the complexes [Sr4Zn4(cbdc)8(H2O)9]n(1) and {[SrCd(cbdc)2(H2O)3] · 3H2O}n(2), the cyclobutane-1,1-dicarboxylate dianions are coordinated to strontium atoms in a chelate fashion to form monomeric mono- and bischelate moieties, which link the d-metal atoms into a polymer structure. An increase in the ion radius of the d-metal in going from zinc(II) to cadmium(II) is accompanied by a decrease in the dimensionality of the coordination polymer from layered to chain. [ABSTRACT FROM AUTHOR]

The reaction of zinc pentafluorobenzoate [Zn(H2O)(C6F5COO)2]n with a pyridine excess (Py, ratio Zn : Py = 1 : 4) affords crystals of complex [Zn2(H2O)(C6F5COO)4(Py)4] (I). The crystal packing of complex I is stabilized by numerous intra- and intermolecular interactions π...π, O...H, F...π, C–H...F, and С–H...O. The compound is characterized by the data of X-ray diffraction (XRD) (CIF file ССDС no. 2157445), IR spectroscopy, C,H,N elemental analysis, and phase XRD analysis. The vaporization of [Zn2(H2O)(C6F5COO)4(Py)4] is studied by the Knudsen effusion method with mass spectral analysis of the gas phase. This process is found to proceed in three stages with the consecutive transition of pyridine molecules to the vapor, partial hydrolysis, and congruent sublimation of zinc pentafluorobenzoate to form free molecules of Zn(C6F5)2 and СО2. The absolute partial pressures of saturated vapor and standard enthalpies of formation are calculated: (Zn(C6F5COO)2, s) ≤ –2634.1 ± 32.2 kJ/mol and (Zn(С6F5)2, g) ≤ –1422.6 ± 31.3 kJ/mol. [ABSTRACT FROM AUTHOR]

Four new complexes [Ln(pfaa)3(H2O)2] n (Ln = Eu (1), Tb (2)) and [Ln2Cd2(pfaa)10 (phen)2(EtOH)2]·2MeCN (Ln = Eu (3), Tb (4), phen = 1,10-phenanthroline) based on pentaphorphenylacetic acid (Hpfaa) have been prepared and completely investigated. The structures of compounds 1 and 3 were studied by single crystal X-ray diffraction analysis: the isostructural complexes 1 and 2 represent 1D coordination polymer, while the isostructural complexes 3 and 4 are molecular compounds. Complexes 1–4 show strong lanthanide-centred luminescence, since the introduction of phenanthroline leads to a significant increase in the observed lifetime (τ obs) and photoluminescent quantum yield. New complexes of Eu3+ and Tb3+ with pentafluorophenylacetic acid have been studied. During synthesis under hydrothermal conditions, polymer structures are formed, while the introduction of phenanthroline and Cd2+ makes it possible to obtain molecular complexes. A change in the structure leads to significant changes in the luminescent properties. [ABSTRACT FROM AUTHOR]

Methods for the synthesis were developed and new homo- and heterometallic cadmium ([Eu2Cd2(MeCN)4(C6F5COO)10] (I), [Tb2Cd2(MeCN)6(C6F5COO)10]·4MeCN (II)) and zinc ([Zn(H2O)(C6F5COO)2] (III), [Eu2Zn2(MeCN)4(C6F5COO)10] (IV)) complexes were characterized. These complexes can be used as precursors for the synthesis of compounds with N-donor ligands. Complexes I and II differ in the coordination of the MeCN molecule, which is coordinated in II by each Tb3+ ion. Also, additional coordination of MeCN induces a greater distortion of the {Tb2Cd2} metal core of II. The crystal packing in I–IV is stabilized by numerous intermolecular O...H, F...F, C–H...F, and C–H...O contacts. The new compounds were characterized by single crystal X-ray diffraction (CCDC no. 2076524 (I), 2082731 (II), 2082803 (III), 2076525 (IV)), IR spectroscopy, C,H,N elemental analysis, and powder X-ray diffraction. [ABSTRACT FROM AUTHOR]

The thermodynamic characteristics of silver perfluorobenzoates C6F5COOAg·0.5C6F5COOH and C6F5COOAg were studied by thermogravimetry, differential scanning calorimetry, and mass spectrometry. It was found that vaporization of these compounds occurs incongruently to give metallic silver and C6F5COOH, C12F10, CO2, and C18F14 molecules. Using the 2nd and 3rd laws of thermodynamics, the standard enthalpy of formation of silver perfluorobenzoate was found to be (C6F5COOAg, cr) = –1195.6 ± 15.7 kJ/mol and the standard enthalpy of formation of the pentafluorobenzoic acid radical was estimated to be (C6F5COO•, cr) = –878.6 ± 25.0 kJ/mol. [ABSTRACT FROM AUTHOR]

A series of heterometallic 1D coordination polymers {[MII(VIVO)(Etmal)2(H2O)5] • 2 H2O}n (MII = Mn (1), Co (2), Ni (3), Cd (4)) were synthesized. These compounds are composed of oxovanadium(iv)-containing mononuclear anionic units [VIVO(Etmal)2]2− linked by d-metal aqua cations. The X-ray diffraction study showed that the nature of the starting d-metal sulfate in the reactions with VOSO4 • 3 H2O and barium salt of ethylmalonic acid (H2Etmal = C3H6(CO2H)2) has no effect on the structure of the resulting coordination polymer. The magnetic isolation of paramagnetic centers in all the synthesized compounds was confirmed by magnetochemical measurements. [ABSTRACT FROM AUTHOR]

By the interaction of cobalt(II) chloride, sodium hydroxide, and pentafluorobenzoic acid (Hpfb) in water the first heterometallic complex of cobalt with pfb– anions is obtained. According to the X-ray crystallographic analysis, the complex is a cationic 1D polymer with the general formula {[Na2Co(pfb)2(H2O)8](pfb)2}n. [ABSTRACT FROM AUTHOR]

The reaction of Cd(NO3)2 · 4H2O and Eu(NO3)3 · 6H2O or Tb(NO3)3 · 6H2O with potassium 3,5-di-tert-butylbenzoate (Kbzo) and N-donor ligands (1,10-phenanthroline (phen), 2,4-lutidine (2,4-lut), 3,4-lutidine (3,4-lut), phenanthridine (phtd), 2,3-cyclododecenopyridine (cdpy), acridine (acr)) afforded heterometallic LnCd2 complexes: [EuCd2(bzo)7(EtOH)2(phen)] (2), [LnCd2(bzo)7(2,4-lut)4] (Ln = Eu (3), Tb (4)), [EuCd2(bzo)7(H2O)2(2,4-lut)2] · MeCN (5), [EuCd2(NO3)(bzo)6(EtOH)2(2,4-lut)2] (6), [EuCd2(bzo)7(H2O)(EtOH)(3,4-lut)2] · 5EtOH (7), 3[EuCd2(bzo)7(H2O)2(phtd)2] · 4phtd (8), [EuCd2(bzo)7(EtOH)3(cdpy)] (9), 2[EuCd2-(bzo)2(EtOH)4] · acr (10). The structures of complexes 2, 3, and 5–10 were determined by single-crystal X-ray diffraction. The isostructurality of complexes 3 and 4 was confirmed by powder X-ray diffraction. The structure of the trinuclear {Ln2Cd} metal core is stable and independent of the type of peripheral ligands coordinated to cadmium atoms. Photoluminescent properties of compounds 3 and 4 were studied. [ABSTRACT FROM AUTHOR]

Abstract: Evaporation of the cadmium pivalate phenanthroline complex Cd2Piv4Phen2 was studied by the Knudsen effusion method with mass spectral analysis of gas phase composition. The evaporation is congruent, and the gas phase consists of CdPiv2Phen molecules. The standard enthalpy of sublimation of these molecules was found. The energy of dissociation of CdPiv2Phen molecules to cadmium pivalate and phenanthroline was determined on the basis of experimental data on ionization. [ABSTRACT FROM AUTHOR]

The reaction products of [Cd(piv)] (piv is-OCBu) with isoquinoline (iqn), 2,4-lutidine (lut), phenanthridine (phend), 2,3-cyclododecenopyridine (cpy), and triethylamine (EtN) were synthesized and their structures were determined. The steric factors were found to play a more important role in cadmium( ii) pivalate complexes compared to 3d metal carboxylates in the +2 oxidation state. The reaction of [Cd(piv)] with isoquinoline produces only the mononuclear complex [Cd(piv)(iqn)] ( 1). The reaction of [Cd(piv)] with pyridine derivatives bearing a bulky substituent at the α position is accompanied by the formation of symmetrical dinuclear complexes of the composition [Cd(piv)(L)]. In the complexes with L = lut ( 2) or phend ( 3), the cadmium( ii) atoms are linked by two chelating-bridging carboxylate groups; in the complex with L = cpy ( 4), by four bidentate-bridging groups. The reaction of [Cd(piv)] with EtN in a solution of MeCN gives the centrosymmetric linear trinuclear complex [Cd(piv)(EtN)] ( 6); in a mixture of benzene and hexane, the ionic compound (HEtN)[Cd(piv)(HO)] ( 7). The crystal structures of all synthesized compounds were determined by X-ray diffraction. [ABSTRACT FROM AUTHOR]

Abstract: Evaporation of the cadmium pivalate phenanthroline complex Cd2Piv4Phen2 was studied by the Knudsen effusion method with mass spectral analysis of gas phase composition. The evaporation is congruent, and the gas phase consists of CdPiv2Phen molecules. The standard enthalpy of sublimation of these molecules was found. The energy of dissociation of CdPiv2Phen molecules to cadmium pivalate and phenanthroline was determined on the basis of experimental data on ionization. [ABSTRACT FROM AUTHOR]

Four new complexes [Ln(pfaa)3(H2O)2] n (Ln = Eu (1), Tb (2)) and [Ln2Cd2(pfaa)10 (phen)2(EtOH)2]·2MeCN (Ln = Eu (3), Tb (4), phen = 1,10-phenanthroline) based on pentaphorphenylacetic acid (Hpfaa) have been prepared and completely investigated. The structures of compounds 1 and 3 were studied by single crystal X-ray diffraction analysis: the isostructural complexes 1 and 2 represent 1D coordination polymer, while the isostructural complexes 3 and 4 are molecular compounds. Complexes 1–4 show strong lanthanide-centred luminescence, since the introduction of phenanthroline leads to a significant increase in the observed lifetime (τ obs) and photoluminescent quantum yield. New complexes of Eu3+ and Tb3+ with pentafluorophenylacetic acid have been studied. During synthesis under hydrothermal conditions, polymer structures are formed, while the introduction of phenanthroline and Cd2+ makes it possible to obtain molecular complexes. A change in the structure leads to significant changes in the luminescent properties. [ABSTRACT FROM AUTHOR]