卷 50, 编号 2 (2024)

The biocompatible metal-organic framework [Zn₄(GA)₄(H₂O)₄] · 4H₂O (H₂GA = glutamic acid) was used as a container for anthocyanins from Hibiscus sabdariffa in composite films based on kappa-carrageenan and hydroxypropyl methylcellulose. The obtained composite materials showed high antioxidant activity and ability to undergo pH-induced color change upon reactions with gaseous products of pathogen development and, hence, possess the potential for practical application as functional materials for food packaging.

The monodentate phosphoryl-containing ligand 1-Ac-2-[Ph₂P(O)]-cyclohexane (L) bearing two asymmetric carbon atoms is synthesized. The study of its crystal structure shows that L is a racemic mixture of (1R,2S) and (1S,2R) stereoisomers. The complex formation of L with TiF₄ in СН₂Сl₂ is studied by ¹⁹F{1Н} and ³¹Р{1Н} NMR spectroscopy. The compositions of the complexes formed in the solution are determined. Racemic and meso-diastereomers of the octahedral complex cis-TiF₄L₂ are formed in the solution as found by an analysis of the ¹⁹F and ³¹Р NMR spectra taking into account the concept of heterotropy of organic compounds. The influence of the optical configuration of stereoisomers of the monodentate ligand coexisting in the coordination sphere of the [MF₄L₂] octahedral tetrafluoro complexes of transition d⁰ metals on the chemical shifts of the fluorine atoms arranged in the trans positions relative to each other is shown. In the meso-diastereomer of cis-TiF⁴L₂, this results in a nonequivalence of the fluorine atoms on the F–Ti–F' ordinate of the octahedron, and the spin-spin coupling constant JFF' = 286.1 Hz is observed in the 19F{1H} NMR spectrum.

Two metal-organic frameworks based on Cd(II) and 2-iodo-(2-I-Bdc) and 2,5-diodo-(2,5-I-Bdc)terephthalate were obtained: {[Cd(2-I-Bdc)(Bbi)]} (I) and {[Cd₂(2,5-I-Bdc)₂(DMF)₂(Bbi)]} (II) (Bbi = 1,1'-(1,4-butanediyl)bis(imidazole)). The structures of both complexes were established by X-ray diffraction (CCDC no. 2258217 (I) and 2257566 (II)).

The complex formation of the redox-active ligand bis(N, N’-2,6-diisopropylphenyl)-9,10-phenanthrenediimine (^DippPDI) with alkaline metal (Li, K) and lanthanide (Sm, Dy) cations is studied. The reduction of ^DippPDI with an alkaline metal excess affords the dianionic form of the ligand (^DippPDA^2–), which crystallizes with the potassium cation as the coordination polymer [K₂(^DippPDA)(Thf)₃] (Thf is tetrahydrofuran, THF). The reaction of equimolar amounts of the lithium salt with the dianionic form of the ligand and neutral diimine affords the lithium complex with the radical-anion form (^DippPSI^•–) crystallized as [Li(^DippPSI)(Thf)₂]. The samarium(III) complex [SmCp*(^DippPDA)(Тhf)] (I) is formed by the reduction of^DippPDI with samarocene [Sm (Thf)₂] (Cp* is pentamethylcyclopentadienide): both the samarium(II) cation and Cp^*– anion are oxidized in the reaction.^DippPDI does not react with similar ytterbocene. The dysprosium(III) complexes are synthesized by the ion exchange reactions between DyI₃(Thf)_3.5 and potassium or lithium salt with the^DippPDA2-dianion. Similar complexes [Dy(^DippPDA)I(Thf)₂] (II^Thf) and [Dy(^DippPDA)I(Thf)(Et₂O)] () are formed in the reactions with the potassium salt depending on the solvent used: a THF-hexane or a diethyl ether-n-hexane mixture, respectively. The coordination of the dysprosium cation by the π system of the conjugated fragment of the NCCN ligand is observed in II^Thf, whereas in this coordination is absent. The reaction with Li₂(^DippPDA) affords the binary complex salt [Li(Тhf)₃(Et₂O)][DyI₂(^DippPDA)(Тhf)] (III, crystallization from a THF-Et₂O mixture). The crystallization from THF gives the [Li(Тhf)₄][DyI₂(^DippPDA)(Thf)] salt (III') containing the same anion as III. The structures of all new complexes are studied by X-ray diffraction (XRD, CIF files CCDC nos. 2260307–2260313).