Stereochemical and Computational NMR Survey of 1,2,3-Triazoles: in Search of the Original Tauto-Conformers.

The conformational analysis of nine functionalized 1,2,3-triazoles was carried out by the correlation of calculated and experimental high-level nuclear magnetic resonance (NMR) chemical shifts. In solution, the studied triazoles are in exchange dynamic equilibrium caused by their prototropic tautomerism of the NH-proton. The experimentally unresolved NMR signals were assigned for most of the compounds.

Data on a two-dimensional Pd-cellulose with optimized morphology for the effective solar to steam generation.

The data presented in this article are related to the research article entitled "Two-dimensional Pd-cellulose with optimized morphology for the effective solar to steam generation (Omelianovych et al., Desalination, 535, 115820 (2023)). We provide complementary analysis of the plasma synthesis parameters, such as plasma power optimization, which were omitted in the original research.

- and -Phosphorylated Enamines-An Avenue to Heterocycles: NMR Spectroscopy.

The review presents extensive data (from the works of the author and literature) on the structure of - and -chlorophosphorylated enamines and the related heterocycles obtained by multipulse multinuclear H, C, and P NMR spectroscopy. The use of phosphorus pentachloride as a phosphorylating agent for functional enamines enables the synthesis of various - and -phosphorylated products that are heterocyclized to form various promising nitrogen- and phosphorus-containing heterocyclic systems. P NMR spectroscopy is the most convenient, reliable and unambiguous method for the study and identification of organophosphorus compounds with different coordination numbers of the phosphorus atom, as well as for the determination of their - and -isomeric forms.

Organophosphorus Azoles Incorporating a Tetra-, Penta-, and Hexacoordinated Phosphorus Atom: NMR Spectroscopy and Quantum Chemistry.

The review presents extensive data (from the author's work and the literature) on the stereochemical structure of functionalized organophosphorus azoles (pyrroles, pyrazoles, imidazoles and benzazoles) and related compounds, using multinuclear H, C, P NMR spectroscopy and quantum chemistry. P NMR spectroscopy, combined with high-level quantum-chemical calculations, is the most convenient and reliable approach to studying tetra-, penta-, and hexacoordinated phosphorus atoms of phosphorylated -vinylazoles and evaluating their Z/E isomerization.

Acrylamide derivatives: A dynamic nuclear magnetic resonance study.

Substituted acrylamides have found an extensive application in organic and medical chemistry; therefore, it is very important to get insight into their features such as electronic structure, spectral properties, and stereochemical transformations. A correct interpretation of the chemical behavior and biological activity of these heteroatomic systems is impossible without knowledge of the structure of stereodynamic forms and factors determining their relative stability. The structure and peculiarities of stereodynamic behavior of substituted acrylamides and their model compounds were studied by dynamic and multinuclear H, C, and N nuclear magnetic resonance (NMR) spectroscopy in CDCl and DMSO-d solution.

Arabinogalactan propargyl ethers in the A-coupling reaction with aldehydes and secondary cyclic amines.

A family of novel pharmacologically prospective carbohydrate polymer aminomethylpropargyl derivatives has been synthesized by CuI-catalyzed A-coupling reaction of arabinogalactan propargyl ethers with aldehydes and secondary amines in DMSO at 23-65 °С. The arabinogalactan derivatives bearing phenyl, pyridinе, and furan moieties in combination with piperidyne, pyrrolidyne, morpholine fragments are prepared in up to 95 % yield and 0.3-2.

Pd-catalyzed cross-coupling of arabinogalactan propargyl ethers with 5-bromosalicylic acid.

New salicylate derivatives of arabinogalactan have been synthesized in up to 90% yield by cross-coupling of propargyl ethers of arabinogalactan with 5-bromosalicylic acid salts. The reaction proceeds in the presence of the catalytic system Pd(PPh)/PPh with CuBr (CuI), and piperidine or 1,8-diazabicyclo-[5.4.

Oxidative cross-coupling of secondary phosphine chalcogenides with amino alcohols and aminophenols: aspects of the reaction chemoselectivity.

Secondary phosphine chalcogenides react with primary amino alcohols under mild conditions (room temperature, molar ratio of the initial reagents 1 : 1) in a CCl4/Et3N oxidizing system to chemoselectively deliver amides of chalcogenophosphinic acids with free OH groups. Under similar conditions, mono-cross-coupling between secondary phosphine chalcogenides and 1,2- or 1,3-aminophenols proceeds only with the participation of phenolic hydroxyl to give aminophenylchalcogenophosphinic O-esters. The yields of the synthesized functional amides or esters are 60-85%.

Multilayered PVDF-HFP Porous Separator via Phase Separation and Selective Solvent Etching for High Voltage Lithium-Ion Batteries.

The development of highly porous and thin separator is a great challenge for lithium-ion batteries (LIBs). However, the inevitable safety issues always caused by poor mechanical integrity and internal short circuits of the thin separator must be addressed before this type of separator can be applied to lithium-ion batteries. Here, we developed a novel multilayer poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) membrane with a highly porous and lamellar structure, through a combination of evaporation-induced phase separation and selective solvent etching methods.

Energy band alignment at the heterointerface between a nanostructured TiO layer and Au(SG) clusters: relevance to metal-cluster-sensitized solar cells.

This study is the first to quantify energy band alignments at a nanostructured TiO/Au(SG) cluster interface using X-ray photoelectron spectroscopy. The d-band of Au clusters shows band-like character and occupied states at the Fermi level are not detected. The results provide evidence of the existence of a finite optical energy gap in Au(SG) clusters and the molecular-like nature of these clusters.

Data on a highly stable electrocatalyst of NiCoPt/Graphene-dot nanosponge for efficient hydrogen evolution reaction.

The data presented in this article are related to the research article entitled "NiCoPt/Graphene-dot Nanosponge as a Highly Stable Electrocatalyst for Efficient Hydrogen Evolution Reaction in Acidic Electrolyte (N.-A. Nguyen et al.

Arabinogalactan propargyl ethers: Au-catalysed hydroamination by imidazols.

A method for the synthesis of pharmacologically prospective arabinogalactan (AG) imidazole- and benzimidazole derivatives in a yield of up to 97 % via Au(III)-catalyzed hydroamination of AG propargyl ethers has been developed. It is found that in the presence of 5 mol% HAuC1 and 10-fold excess imidazole relative to the propargyl groups, the hydroamination successfully competes with cross-linking processes to afford products soluble in DMSO and aqueous HC1 solutions (degree of substitution of imidazolylpropenyl fragments 0.5-1.

Sol-Gel Processed TiO Nanotube Photoelectrodes for Dye-Sensitized Solar Cells with Enhanced Photovoltaic Performance.

The performance of dye-sensitized solar cells (DSCs) critically depends on the efficiency of electron transport within the TiO-dye-electrolyte interface. To improve the efficiency of the electron transfer the conventional structure of the working electrode (WE) based on TiO nanoparticles (NPs) was replaced with TiO nanotubes (NTs). Sol-gel method was used to prepare undoped and Nb-doped TiO NPs and TiO NTs.

Circulating antiplatelet antibodies in pregnant women with immune thrombocytopenic purpura as predictors of thrombocytopenia in the newborns.

Newborns from mothers with immune thrombocytopenic purpura (ITP) have a risk of thrombocytopenia due to passage of maternal antiplatelet antibodies into fetal/neonatal circulation. We looked for predictors of neonatal thrombocytopenia (nTP) in pregnant women with ITP. One hundred pregnant women with platelet count <100 × 10/l, no non-immune causes of thrombocytopenia and increased platelet associated IgG (PA-IgG) were included in the study.

Wet Pretreatment-Induced Modification of Cu(In,Ga)Se/Cd-Free ZnTiO Buffer Interface.

We report a novel Cd-free ZnTiO buffer layer deposited by atomic layer deposition for Cu(In,Ga)Se (CIGS) solar cells. Wet pretreatments of the CIGS absorbers with NHOH, HO, and/or aqueous solution of Cd ions were explored to improve the quality of the CIGS/ZnTiO interface, and their effects on the chemical state of the absorber and the final performance of Cd-free CIGS devices were investigated. X-ray photoelectron spectroscopy (XPS) analysis revealed that the aqueous solution etched away sodium compounds accumulated on the CIGS surface, which was found to be detrimental for solar cell operation.

[The heredity and the curvature of the nasal septum in the children].

The objective of the present study was to elucidate the role of genetic and environmental factors in the development of the curvature of the nasal septum in the children by means of the twin method. A total of 171 twins were examined during the study. They included 27 pairs of monozygotic (MZ) twins and 1 triplet.

Cross-coupling of propargylated arabinogalactan with 2-bromothiophene.

Novel pharmacologically prospective derivatives of arabinogalactan (a polysaccharide from larch wood) containing acetylenic and thiophene moieties have been obtained in up to 90% yield by cross-coupling of propargylic ethers of arabinogalactan with 2-bromothiophene. The reaction proceeds in the presence of the catalytic system Pd(Ph3P)4/CuBr/LiBr and piperidine in DMSO at 80-85°С. An advantageous feature of the synthesis is that it requires 5-25 times lesser catalytic loading than in common Sonogashira protocols thus making the reaction particularly beneficial to synthesize pharmaceutically-oriented polysaccharides.

Modification of arabinogalactan propargyl ethers by triazolyl functions.

Polysaccharide arabinogalactan (AG) has been modified by triazolyl functions via the copper-catalyzed 1,3-dipolar addition of azides to propargyl ethers. A range of new AG triazolo derivatives bearing benzyl, 4-vinylbenzyl, 1-naphthylmethyl, (1-vinylimidazol-2-yl)methyl, (1-ethylimidazol-2-yl)methyl, (1-vinylbenzimidazol-2-yl)methyl, allyl, carboxymethyl (as Na-salt) substituents is prepared by "one-pot" approach from organic azides generated in situ and AG propargyl ethers. The latter (degree of substitution 2.

Graphene-NiO nanohybrid prepared by dry plasma reduction as a low-cost counter electrode material for dye-sensitized solar cells.

NiO nanoparticles (NPs) were hybridized on the surface of reduced graphene oxide (RGO) by dry plasma reduction (DPR) at atmospheric pressure without any toxic chemicals and at a low temperature. NiO-NPs of 0.5-3 nm size, with a typical size of 1.

Graphene-platinum nanohybrid as a robust and low-cost counter electrode for dye-sensitized solar cells.

Dry plasma reduction (DPR) is an excellent approach for easily, continuously, uniformly and stably hybridizing platinum nanoparticles (Pt-NPs) on a graphene-coated layer under atmospheric pressure without any toxic chemicals and at a low temperature. The Pt-NPs with a size of 0.5-4 nm and mostly 2 nm were stably and uniformly hybridized on the surface of reduced graphene oxide (RGO) after co-reduction of Pt precursor ions and GO to Pt atoms and RGO, respectively.

Propargylation of arabinogalactan with propargyl halides--a facile route to new functionalized biopolymers.

New arabinogalactan propargyl ethers with degree of substitution (DS) up to 2.8 have been obtained by propargylation of arabino-3,6-galactan (AG) with propargyl bromide (PB) in the two-phase system 30-60% КОН aqueous solution/toluene in the presence of triethylbenzylammonium chloride (TEBAС) or without catalyst (ambient temperature, 1-24 h) in 20-87% yields. The highest yields have been reached using TEBAС as phase-transfer catalyst, though the non-catalytic version proves to be also efficient (DS 2.

Cd-free CIGS solar cells with buffer layer based on the In2S3 derivatives.

This study guided by device evaluations was conducted to reveal the reasons for the loss of the photo-generated carriers in CIGS cells with the buffer based on In2S3 derivatives. Chemical bath deposited Inx(OOH,S)y films have been employed as a Cd-free buffer layers. When compared to solar cells with CdS buffer layer, the Cu0.

Design of energy band alignment at the Zn(1-x)Mg(x)O/Cu(In,Ga)Se2 interface for Cd-free Cu(In,Ga)Se2 solar cells.

The electronic band structure at the Zn(1-x)Mg(x)O/Cu(In(0.7)Ga(0.3))Se(2) interface was investigated for its potential application in Cd-free Cu(In,Ga)Se(2) thin film solar cells.

The effects of intramolecular and intermolecular coordination on (31)P nuclear shielding: phosphorylated azoles.

The effects of intramolecular and intermolecular coordination on (31)P nuclear shielding have been investigated in the series of tetracoordinated, pentacoordinated and hexacoordinated N-vinylpyrazoles and intermolecular complexes of N-vinylimidazole and 1-allyl-3,5-dimethylpyrazole with phosphorous pentachloride both experimentally and theoretically. It was shown that either intramolecular or intermolecular coordination involving phosphorous results in a dramatic (31)P nuclear shielding amounting to approximately 150 ppm on changing the phosphorous coordination number by one. A major importance of solvent effects on (31)P nuclear shielding of intramolecular and intermolecular complexes involving N → P coordination bond has been demonstrated.

Radical anions of flavonoids.

Several representatives of natural flavonoids and their synthetic nitro-derivatives have been investigated by polarography and electron paramagnetic resonance (EPR) spectroscopy under electrochemical reduction in acetonitrile, dimethylformamide (DMF), dimethylsulfoxide (DMSO) or 1,2-dimethoxyethane. All the compounds studied are reduced in the first stage by one-electron transfer, apart from flavanone, which accepts two electrons simultaneously. However, the primary radical anions were detected by EPR spectroscopy only for 4'-nitroflavone.