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Vol 49, No 11 (2023)
Articles
К 70-летию академика Михаила Петровича Егорова
667-668
Heterometallic Carboxylate Complexes with {Co2Ln} and {Co2Li2} Metal Cores: Synthesis, Structures, and Magnetic Properties
Abstract
The results of studying the heterometallic trinuclear {CoLn} and tetranuclear {CoLi2} carboxylate coordination compounds are systematized. The methods of the syntheses are discussed, and the structures and magnetic properties are considered
669-684
Synthesis and Structure of the (µ2-OP(O)Ph2)-Linked Dimeric Amide Lanthanum Complex {[ CP(O)Ph2]La[N(SiMe3)2](µ2-OP(O)Ph2)}2 Bearing the Tridentate Heteroscorpionate Ligand. Investigation of the Catalytic Activity in rac-Lactide and ε-Caprolactone Polymerization
Abstract
The dimeric amide lanthanum complex {[CP(O)Ph2]La[N(SiMe3)2](µ2-OP(O)Ph2)}2 (PzlMe2 is 3,5-dimethylpyrazole) bearing the N,N,O-tridentate heteroscorpionate ligand is synthesized. As found by X-ray diffraction (XRD) (CIF file CCDC no. 2212274), the complex is binuclear and its lanthanum ions are linked by two bridging monoanionic diphenyl phosphinate ligands. The synthesized lanthanum complex demonstrates a high catalytic activity in the polymerization with ring opening of rac-lactide and ε-caprolactone providing the quantitative conversion of 500 equivalents of the monomer to the polymer at room temperature within 360–720 min for rac-lactide and 10–30 min for ε-caprolactone. The formed polylactides are characterized by the atactic microstructure (Pr = 0.54–0.56) and polydispersity indices (PDI) of 1.6–2.5, whereas for polycaprolactone PDI = 2.1–2.8.
685-692
Coordination Polymer or Cluster: Zinc Bis(3,5-di-tert-octyl-semiquinolate) with Pyrazine
Abstract
New zinc bis-o-semiquinolate complexes based on 3,5-di-tert-octyl-o-benzoquinone bearing the N-donor ligand (pyrazine) coordinated to the metal are synthesized. Two different products can be obtained depending on the synthesis method: coordination polymer (direct oxidation of metallic zinc with o-quinone (CIF file CCDC no. 2250574 (I)) or polynuclear cluster (exchange reaction (CIF file CCDC no. 2250575 (II)). The coordination polymer is linear and free of intermolecular π,π interactions between the aromatic fragments of the adjacent molecules. The magnetochemical study of complexes I and II shows that intramolecular antiferromagnetic exchange interactions between spins of the o-semiquinolate radical centers dominate.
693-705
Heterophase Synthesis of Silver Trifluoroacetate with Copper, Indium, and Zinc. Standard Enthalpy of Formation of Copper Trifluoroacetate
Abstract
Solid-phase reactions of silver trifluoroacetate CF3COOAg with copper, indium, and zinc are studied by thermogravimetry, differential scanning calorimetry, and mass spectrometry. In a temperature range of 358–428 K, the reactions are found to afford trifluoroacetates of these metals without mass loss of the weighed samples. The obtained experimental data make it possible to calculate the enthalpy of formation of copper trifluoroacetate H298 (CF3СООСu, cr) = –1020.5 ± 18.0 kJ/mol.
706-710
Structure and Magnetic Properties of the Single Crystal of the Liquid-Crystalline Cu(II) Complex with β-Enaminoketone
Abstract
The structure and magnetic properties of the single crystal of bis{1-[4-(4-pentyloxybenzoyl-oxy)phenyl]-1-amino-3-pentylprop-1-en-3-onate}copper(II), which shows nematic mesomorphism, were studied by X-ray diffraction and electron spin resonance spectroscopy.
711-718
Complexes of Silver 1,1,1,5,5,6,6,6-Octafluorohexane-2,4-dionate with π-Donor Ligands: Synthesis, Structure, and Thermal Properties
Abstract
Two new Ag(I) complexes with 1,1,1,5,5,6,6,6-octafluorohexane-2,4-dionate ion (Ofhac) and π‑donor neutral ligands, vinyltriethylsilane (VTES) or cycloocta-1,5-diene (COD), were synthesized with the goal to expand the library of silver precursors for chemical vapor deposition. The products were characterized by elemental analysis and IR and NMR spectroscopy. The complex [Ag(VTES)(Ofhac)] (I) was liquid under standard conditions; the temperature of its crystallization was below –20°C. Treatment of I with benzene gave rise to crystals of [Ag4(C6H6)2(Ofhac)4]∞ (II), which was confirmed by NMR and X-ray diffraction (CCDC no. 2232810). The structure of [Ag(COD)(Ofhac)]2 (III) was established by X-ray diffraction (CCDC no. 2232809). The binuclear molecules are formed due to the μ2-κ1(O):κ1(O') function of the Ofhac ligands (Ag–O, 2.458(2)–2.461(2) Å), while COD is κ2-η2:η2-coordinated (Ag–C, 2.420(17)–2.684(11) Å). The thermal properties of I and III in comparison with analogues containing 1,1,1,5,5,5-hexafluoropentane-2,4-dionate ion (Hfac) were studied by thermogravimetry.
719-728