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Halide perovskite nanocrystals are a family of nanomaterials with a high prospect for use in light-emitting devices, lasers, and quantum optics, which makes their integration into photonic circuits...

Co-crystallization of dithiocarbamate complexes [MII(S2CNEt2)2] (M = Cu 1, Ni 2, Pd 3, Pt 4) and 1,3,5-triiodotrifluorobenzene (FIB) gives an isomorphic series of (1–4)·2FIB co-crystals exhibiting quadruple Cu/Ni/Pd/Pt isostructural exchange. In the structures of (1–4)·2FIB, the halogen-bonded C–I⋯M (Ni, Pd, Pt) and semicoordination M⋯I–C (Cu) metal-involving contacts were identified by X-ray diffractometry and their nature was verified theoretically. The directionality of the Iσ-hole⋯d2zMII and MII⋯Ielectron belt interactions depends on the identity of a metal center: on going from a rather electrophilic CuII to substantially more nucleophilic NiII, PdII, and PtII centers, we observed the electron belt-to-σ-hole switch of a noncovalently bound iodine(I) of FIB and, correspondingly, its shift from semicoordination to halogen bonding. The negative values of the electrostatic potentials (given in parentheses) were estimated for all metal centers and they decrease in the order CuII (−8.8) > NiII (−24.5) > PdII (−28.6) > PtII (−33.3 kcal mol−1). Despite the negative potentials at all MIIs, the semicoordinative contact Cu⋯I was established by the recognition of the LP(I) → LP*(Cu) charge transfer using natural bond orbital (NBO) analysis and the comparison of electron density (ED) and electrostatic potential (ESP) minima positions along the I⋯Cu bond paths. In the case of the rather nucleophilic (although positively charged) PdII and PtII centers, the contacts C–I⋯d2z[Pd] and C–I⋯d2z[Pt] can be attributed to the unconventional metal-involving halogen bonding; these contacts are among the strongest (4.30 and 5.42 kcal mol−1, correspondingly) between any metal center and iodine(I)-based σ-hole donors.

The complex [Ni(S2COEt)2] (1) and 1,4-diiodotertafluorobenzene (1,4-FIB) or 1,3,5-triiodotrifluorobenzene (1,3,5-FIB) were cocrystallized to form solid adducts 1·2(1,4-FIB) and 1·2(1,3,5-FIB), resp...

The reaction between pyrazole (PzH), the N,N-disubstituted cyanamides NCNR2 (R2 = Me2, Et2, C4H8, C5H10, C5H10O), and the nickel salts NiX2·nH2O (X = NO3, OTf, ClO4, Cl, OTs, n = 6; Br, n = 3) affords complexes featuring ligands derived from the NiII-mediated cyanamide–pyrazole coupling. The composition of the products and their yields are strongly affected by the choice of NiX2·nH2O and a molar ratio between the reactants. The [Ni(PzH)2{NHC(NR2)Pz}2](X)2 ([1–5](X)2; R2 = Me21, Et22, C4H83, C5H104, C5H10O 5; X = NO3, OTf – in all combinations, and R2 = Me21 for X = Cl, Br) complexes (named here as bis-chelate complexes), featuring two chelated ligands derived from the cyanamide–pyrazole coupling, were obtained selectively from NiX2·nH2O when the molar ratio between the reactants NiX2 : PzH : NCNR2 was 1 : 4 : (2.3). By using NiX2·6H2O (X = ClO4, OTs) and with the molar ratio NiX2 : PzH : NCNR2 1 : 3 : (3.5), the pure tris-chelate species [Ni{NHC(NR2)Pz}3]X2 ([6–7](ClO4)2, R2 = C4H86, C5H107; [8](OTs)2, R2 = Me2) were isolated. Structurally similar complexes are not formed under the coupling conditions when conventional nitriles NCR (R = Alk; for instance, NCMe) were applied as the nitrile component of the reaction. Quantum-chemical calculations demonstrate that generation of the tris-chelate [Ni{NHC(NR2)Pz}3]2+ species is thermodynamically driven with the energetic difference 4.6 kcal mol−1 between appropriate bis- and tris-chelate products, while for conventional nitrile derivatives the bis-chelate products are thermodynamically more preferable. The structures of eight complexes, viz. [1](Cl)2, [1–2](NO3)2, [4](NO3)2, [1–2](OTf)2, [3](OTf)2·Me2CO, and [9](OTf)2 were established by single crystal X-ray diffraction.

Four new ionic diimine Cu(I) complexes with general formula [Cu(POP)(NN)]BF4 have been synthesized by convenient methods from readily available starting materials. All the complexes were characterized by a range of spectroscopic, electrochemical, and computational techniques and, in the cases of 1, 2, and 3, by single crystal X-ray diffraction. The complexes are emissive in the solid state at ambient temperature and the emission maxima are located in the orange range. Furthermore, the suitability of these complexes for application in organic light-emitting diodes (OLEDs) has been demonstrated in a solution-processed device.

Two annulated triazapentadiene systems, viz. 1,3,5,7,9-pentaazanona-1,3,6,8-tetraenate chloride complexes of PtII, form CCl4 solvates, containing the Cl3C–Cl···Cl–Pt halogen bonds. These halogen bonds are firstly reported type of Cl3C–Cl···Cl–M contacts. In the X-ray structures of two solvates different non-covalent interactions were detected and studied by DFT calculations and topological analysis of the electron density distribution within the framework of QTAIM method at the M06/DZP-DKH level of theory. Estimated energies of these supramolecular contacts vary from 0.6 to 2.4 kcal/mol.

These days halide perovskite is a very popular material to be applied both in photovoltaics and photonics due to its unique properties and low-cost methods of fabrication. High photoluminescence quantum yield and good nonlinear coefficients of perovskite material allow achieving multiphoton absorption in perovskite. Encapsulation of perovskite quantum dots in polymer matrix enables to prevent interaction with the environment and increase the material lifetime. In this paper, we present a semitransparent visualizer of infrared lasers working on two-photon absorption in halide perovskite nanocrystals encapsulated in the polymer matrix.

Tetramethyl orthosilicate and triethoxyphenylsilane, which contains hydrophobic phenyl groups, were used as a silica (SiO2) source in a modified ligand-assisted reprecipitation synthesis approach for the fabrication of water-stable perovskite nanocrystals. Hydrolysis-condensation reaction of tetramethyl orthosilicate and triethoxyphenylsilane results in a formation of 3D siloxane network. Employing triethoxyphenylsilane in the synthesis enhances the hydrophobic properties of the SiO2 shell, which increases the stability of perovskites in aqueous medium. The stability of the CsPbBr3@SiO2 nanocrystals was estimated after 24 h of water exposure by the photoluminescence measurements at different time points. The synthesized CsPbBr3@SiO2 nanocrystals were visualized during in vitro experiments with murine melanoma B16-F10 cells. Hence, the potential of CsPbBr@SiO2 nanocrystals for bioimaging purposes was observed.

The absorption of a nanocomposite of silver nanoparticles and arabinogalactan in the UV–Vis spectral range is due to the presence of end aldehyde groups in the arabinogalactan and plasmon vibrations in 0D nanosilver. The absorption spectrum of a fundamentally new nanocomposite of silver with arabinogalactan-g-polypyrrole block copolymer reveals additional long-wavelength overlapping absorption bands resulting from the longitudinal component of plasmon resonance in 1D nanosilver and polarons in polypyrrole.

Pyridine-N-oxides bearing a pharmacophoric oxadiazole moiety could be C H functionalized via the acid-catalyzed reaction with dialkylcyanamides, providing access to hitherto undescribed pyridine-2-yl substituted ureas, which have potential as “lead-like” scaffolds for medicinal chemistry. Atom-economy, environmental friendliness (no halide-containing or toxic reagents), simple work-up, as well as scalability are the main advantages of the employed procedure.

Representatives of modern topical hemostatics used most widely in practical medicine, which are conventionally divided according to their nature and mechanism of action, are analyzed. The results of innovative design of new-generation styptics based on polymetalloacrylates are summarized. Potential hemostatic agents with unique properties that can serve as versatile means for rapid blood clotting in a variety of surgical procedures, even for patients with impaired blood coagulation and upon wounds and injuries in emergency situations, for considerable acceleration of wound healing, repair regeneration process in skin burns due to their antimicrobial and anesthetic properties are proposed.

Secondary phosphine chalcogenides react with diacetone-d-glucose (DAG) in the system CCl4/Et3N (70°C, 4–24 h) to afford DAG chalcogenophosphinates in up to 79% yield, thus paving a short way to optically active chalcogenophosphinates with glucose moieties. As an example, a mild regioselective hydrolysis (70°C, aqueous MeCOOH) of DAG bis(2-phenylethyl)selenophosphinate) obtained leads to monoacetone-d-glucose bis(2-phenylethyl)selenophosphinate.

Original method has been developed for the preparation of previously unknown cyclic organosilicon esters of salicylic acid, containing halogen–silicon bonds. This method is based on the reaction of trimethylsilyl ester of 2-(trimethylsiloxy)benzoic acid with organylhalosilanes RR1SiXY under mild conditions, where R, R1 = Cl, Me, CH=CH2, Ph; X, Y = Cl, F.

Replacement of amide moiety with the 1,2,4-oxadiazole core in the scaffold of recently reported efflux pump inhibitors afforded a novel series of oxadiazole/2-imidazoline hybrids. The latter compounds exhibited promising antibacterial activity on both Gram-positive (Staphylococcus aureus, Bacillus subtilis) and Gram-negative (Escherichia coli, Pseudomonas fluorescens) strains. Furthermore, selected compounds markedly inhibited the growth of certain drug-resistant bacteria. Additionally, the study revealed the antiproliferative activity of several antibacterial frontrunners against pancreas ductal adenocarcinoma (PANC-1) cell line, as well as their type-selective monoamine oxidase (MAO) inhibitory profile.

A method of synthesis of phenylhalosilazanes by the reaction of phenyl(fluoro)chlorosilanes PhSiF3–nCln (n = 0–3) with hexamethyldisilazane at room temperature is elaborated. The thermolysis of 1,1,1-trimethyl-3-phenyl-3,3-difluorodisilazane affords cyclic phenylfluorosilazanes (PhSiFNHSiMe3)n (n = 3–5). The process may occur via the intermediate formation of phenylfluorosilimine.

219 Compounds containing asymmetric silicon atom have long attracted the attention of researchers [1–4]. The known methods of synthesis of chiral silicon com pounds containing simultaneously two different halo gen atoms are based either on the treatment of hydro carbylfluorosilanes with aluminum chloride [5] and their analogs containing Si–H bonds with copper chloride [6], or irradiation of reaction mixtures of hexafluoro and pentafluorochlorobenzene [7] or 1,4 dichlorotetrafluorobenzene [8] with trichloro and methyldichlorosilanes by accelerated electrons. We have found a simplest and convenient method for the synthesis of compounds of such a type. It is based on the displacement of one of the chlorine atoms in phenyl(fluoro)dichlorosilane (I) by OR, OC(O)R, OSiMe3, NHSiMe3, OSiMe2OSiMe3, and other groups. All compounds resulting from this reac tion were previously unknown.

The structure and properties of fluorosilicon polymer (fluorosil) formed by the reaction of phenyltrifluorosilane with aliphatic alcohols have been studied by the methods of IR, 19F, 29Si NMR spectroscopy, high temperature mass-spectrometry, derivatography and atom emission analysis. Due to its high reactivity, this polymer readily reacts with glass of the reaction vessel extracting the ions of all metals entering into its composition. Fluorosil formed in a quartz, teflon or polypropylene reactors is characterized by low stability and is slowly decomposed to SiF4 and SiO2. Apparently, fluorosil is the product of incorporation of SiF4 into the SiO2 matrix.

The kinetics of radical polymerization of 1-vinyl-3-amino-1,2,4-triazole was studied. The results show that the presence of the amino group as a substituent on the heterocycle decreases the polymerization activity of the triazole-containing monomer. It was found that water has an accelerating effect on the 1-vinyl-3-amino-1,2,4-triazole polymerization process. The substitution of the amino group on the triazole cycle enhances the hydrophilic properties of the polymer relative to those of unsubstituted polyvinyltriazole and opens up possibilities for its further modification.

Original method has been developed for the preparation of previously unknown cyclic organosilicon esters of salicylic acid, containing halogen–silicon bonds. This method is based on the reaction of trimethylsilyl ester of 2-(trimethylsiloxy)benzoic acid with organylhalosilanes RR1SiXY under mild conditions, where R, R1 = Cl, Me, CH=CH2, Ph; X, Y = Cl, F.

The method of synthesis of the hitherto unknown class of organosilicon compounds, phenyl(acyloxy)fluorosilanes C6H5Si(OCOR) n F3−n (n = 1, 2) and phenyl(acyloxy)fluorochlorosilanes C6H5Si(OCOR) FCl in up to 91% yield has been developed based on the reaction of phenyl(fluoro)chlorosilanes C6H5SiCl n F3−n (n = 1, 2) with trimethylsilyl esters of carboxylic acids Me3SiOC(O)R [R = H, CH3, CF3, CCl3, ClCH2, BrCH2, CH2=CHCH3, CH2=CHPh, CH(CH3)=CH2, Ph].

Cohydrolysis of phenyltrichlorosilane with phenyl(fluoro)dichloro- and phenyl(difluoro)-chlorosilanes and thermolysis of the formed siloxanes leading to the formation of phenyl(difluoro)chlorosilane are studied. The scheme of thermal decomposition of disiloxanes possessing fluorine atoms in the 1,3 positions is suggested. The scheme is based on the intermediate formation of an active four-membered cyclic complex closed by the fluorine bridge between the silicon atoms. In agreement with the scheme, no thermolysis of 1,3-diphenyl-1-fluoro-1,3,3-trichlorodisiloxane is observed under the studied conditions.

The large difference in the reactivity of PhSiF2Cl (I) and PhSiF3 is convincingly confirmed by the competitive reaction of their mixture with HMDS in a 1 : 1 : 1 molar ratio at ambient temperature. The reaction leads only to phenylfluorosiloxane (III) and trimethylchlorosilane in accordance with equation (3). At the same time, no trimethylfluorosilane was detected in the reaction mixture, while all PhSiF3 remained unchanged. PhSiFCl2 Me3SiOSiMe3 +

The siloxane bond splitting reaction in hexamethyldisiloxanes PhSiCl n F3−n was studied.