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Heterobimetallic lanthanide conjugates were obtained by click-reaction between two monometallic lanthanide complexes with Schiff bases for the first time. For that, novel azido- and ethynyl-substituted ligands, as well as their lanthanide complexes, were obtained and characterised; two new crystal structures were obtained. Click-reaction between ligands and complexes was performed, and the latter was demonstrated to result in the conjugates {Ln1–Ln2} formation. Among the obtained conjugates, {Yb–Nd} and {Yb–Er} demonstrated intense NIR emission with temperature sensitivity in the physiological range of up to 3%/K. [ABSTRACT FROM AUTHOR]

The strategy of incorporating self‐assembled monolayers (SAMs) with anchoring groups is an effective and promising method for interface engineering in perovskite solar cells with metal oxide charge‐transporting layers. However, coating SAM layers in upscaled perovskite solar modules (PSMs) using slot‐die coating is challenging due to the low viscosity and wettability of the solutions. In this study, a triphenylamine‐based polymer poly([{5‐[4‐(diphenylamino)phenyl]‐2‐thienyl}(4‐fluorophenyl)methylene]malononitrile) (pTPA)–TDP, blended with SAM based on 5‐[4‐[4‐(diphenylamino)phenyl]thiophene‐2‐carboxylic acid, is integrated to address these challenges. And, p–i–n‐oriented PSMs on 50 × 50 mm2 substrates (12 sub‐cells) are fabricated with a NiO hole‐transport layer and organic interlayers for surface modification. Wetting angle mapping shows that ununiform regions of the slot‐die‐coated SAM has extreme hydrophobicity, causing absorber thickness fluctuations and macro‐defects at buried interfaces. The blended interlayer at the NiO/perovskite junction homogenizes surface wettability and mitigates lattice strain, enabling the effective use of SAM properties on large surfaces. This improved energy level alignment, enhancing the power conversion efficiency of the modules from 13.98% to 15.83% and stability (ISOS‐L‐2, T80 period) from 500 to 1630 h. In these results, the complex effects of using SAM in slot‐die‐coating technology for large‐scale perovskite photovoltaics are highlighted. [ABSTRACT FROM AUTHOR]

The synthesis of a variety of polyazamacrocyclic compounds comprising structural units of tris(3-aminopropyl)amine (TRPN) and oxadiamines, decorated with one or two fluorophore groups (dansyl or quinoline) at different nitrogen atoms, was carried out using Pd(0)-catalyzed amination. The dependence of the yields of the macrocycles on the synthetic path was observed. The spectrophotometric and fluorescent properties of the target compounds were studied, and their coordination with metal cations using UV–vis, fluorescence spectra as well as NMR titration was investigated. The stoichiometry and binding constants of several complexes with Cu(II), Zn(II), Cd(II), Pb(II) and Hg(II) were established. Three of the six studied macrocycles can be judged as prospective detectors of Zn(II) cations due to the substantial enhancement of fluorescence. [ABSTRACT FROM AUTHOR]

A method for the synthesis of a new family of cryptands containing 1,4,7-triazacyclononane and 1,5,9-triazacyclododecane moieties and dansyl fluorophore groups has been elaborated starting from free triazacycloalkanes and employing Pd(0)-catalyzed amination at the macrocyclization step. The dependence of the products yields on the nature of reagents has been established. The majority of synthesized macrobicycles have been evaluated as possible chemosensors for detecting metal cations. Compound comprising 1,4,7-triazacyclononane and dioxadiamine linker proved to be a prospective colorimetric sensor for Cu(II) by changing its absorption spectrum in the presence of this cation, while other cryptands demonstrated full quenching of fluorescence in the presence of Cu(II) and Al(III) what makes them promising fluorescent molecular probes for these metals. [ABSTRACT FROM AUTHOR]

CuI-Catalyzed amination of 2-bromo-, and 2-, 3-, and 4-iodopyridines with tri- and tetraamines aimed at the synthesis of N, N′-diheteroaryl derivatives was studied. A strong dependence of the product yields on the nature of starting compounds and the ligand used was observed. The increase in the number of ethene-1,2-diamine fragments in the polyamine structure led to the increase in the yields of polyheteroarylated compounds, whereas propane-1,3-diamine fragments favored the formation of monopyridinyl derivatives and promoted the heteroarylation of the secondary amino groups. 2-Iodopyridine, as a more reactive compound, readily formed N, N-diarylated products. The best yields of the target N, N′-dipyridin-2-yl derivatives were 76% in the case of the triamine and 68% in the case of the tetraamine. A comparison of CuI- and Pd0-mediated heteroarylation of polyamines was also presented. [ABSTRACT FROM AUTHOR]

Pd-catalyzed amination of isomeric 2,6-, 2,8-, 4,8- and 4,7-dichloroquinolines was studied using adamantane-containing amines in which substituents at the nitrogen atom differ in bulkiness. The selectivity of the amination of 2,6-dichloroquinoline was very low, substantially better results were obtained with 2,8-dichloroquinoline, and 4,8- and 4,7-dichloroquinolines provided the best yields of the amination products. Diamination of 4,8- and 4,7-dichloroquinolines was carried out with two amines which differ strongly in the bulkiness of the alkyl group. In the majority of cases BINAP ligand was successfully applied, however, it had to be replaced with DavePhos in certain reactions when using the most sterically hindered amine as well as for the diamination reactions. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is a neurodegenerative disease incurable due to late diagnosis and treatment. Therefore, one of the priorities of neurology is to study the mechanisms of PD pathogenesis at the preclinical and early clinical stages. Given the important role of sphingolipids in the pathogenesis of neurodegenerative diseases, we aimed to analyze the gene expression of key sphingolipid metabolism enzymes (ASAH1, ASAH2, CERS1, CERS3, CERS5, GBA1, SMPD1, SMPD2, UGCG) and the content of 32 sphingolipids (subspecies of ceramides, sphingomyelins, monohexosylceramides and sphinganine, sphingosine, and sphingosine-1-phosphate) in the nigrostriatal system in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse models of the preclinical and clinical stages of PD. It has been shown that in PD models, the expression of five of the nine studied genes (CERS1, CERS5, ASAH1, ASAH2, and GBA1) increases but only in the substantia nigra (SN) containing dopaminergic cell bodies. Changes in the expression of enzyme genes were accompanied by an increase in the content of 7 of the 32 studied sphingolipids. Such findings suggest these genes as attractive candidates for diagnostic purposes for preclinical and clinical stages of PD. [ABSTRACT FROM AUTHOR]

N-heteroaryl substituted adamantane-containing amines are of substantial interest for their perspective antiviral and psychotherapeutic activities. Chlorine atom at alpha-position of N-heterocycles has been substituted by the amino group using convenient nucleophilic substitution reactions with a series of adamantylalkylamines. The prototropic equilibrium in these compounds was studied using NMR spectroscopy. The introduction of the second amino substituent in 4-amino-6-chloropyrimidine, 2-amino-chloropyrazine, and 1-amino-3-chloroisoquinoline was achieved using Pd(0) catalysis. [ABSTRACT FROM AUTHOR]

Pd(0)-catalyzed amination was employed for the synthesis of a new family of (S)-1,1′-bianaphthalene-2,2′-diamine derivatives possessing additional chiral and fluorophore substituents. The Compounds thus obtained were tested as potential detectors of seven amino alcohols, and some of them were found to be able to recognize individual enantiomers of certain amino alcohols by specific changes of their emission spectra in the presence of these analytes. A pronounced dependence of the detecting abilities on the nature of the substituents in the (S)-BINAM derivatives was observed. [ABSTRACT FROM AUTHOR]

The comparison of the possibilities of Pd- and Cu-catalyzed amination reactions using fluorine-containing aryl bromides and iodides with oxadiamines to produce their N,N′-diaryl derivatives was carried out. The dependence of the reactivity of the aryl halides on the nature of the substituents and halogen atoms as well as on the structure of oxadiamines was investigated. It was found that the copper-catalyzed reactions were somewhat comparable with the palladium-mediated processes in the majority of cases, especially in the reactions with para-fluorine- and para-(trifluoromethyl)-substituted aryl halides, although the necessity to use aryl iodides in the Cu(I)-catalyzed amination was obvious. Pd catalysis was found inevitable for the successful amination of more sterically hindered ortho-(trifluoromethyl)aryl bromides. [ABSTRACT FROM AUTHOR]

Both dimeric μ-chlorine bridged and monomeric bidentate Pd(II) complexes with SCN hybrid pincer-type ligands, bearing thiophosphoryl group and imine moiety of the benzothiazole ring as coordination arms, formed in the reaction with (PhCN)(2)PdCl(2) under kinetic control (20 °C, dichloromethane solution) were readily converted into the corresponding SCN pincer complexes via solid phase synthesis (neat, 200 °C, 15 min). The synthesis of pincer complexes can be performed also by heating (200 °C, 5 min) of a homogeneous mixture of the initial reactants, namely, the ligand and (PhCN)(2)PdCl(2), obtained by manual grinding in a mortar. The efficacy of solid phase approaches is comparable with the analogous synthesis in solutions under severe conditions., (This journal is © The Royal Society of Chemistry 2011)

Mass spectrometry proved itself to be a powerful tool to predict the directions and yields of mono- molecular reactions of organic compounds. Electron ionization (EI) and electrospray ionization (ESI) were used to study possible transformations of N-(ortho-cyclopropylmethylphenyl)arylamides I and N-(ortho- cyclopropylmethylphenyl)arylthioamides II as well as their para-isomers III and IV in a mass spectrometer and to predict directions and yields of their acid catalyzed cyclization reactions. Several five-eight-membered heterocycles were proposed as possible products of intramolecular transformations of compounds I and II. Reactions of compounds I and II in sulfuric acid solutions were carried out and the results obtained were compared with mass spectrometric data. Surprisingly, EI of the studied compounds mimics their solution reactions better than ESI.