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New energetic materials based onN,N′-methylene bridged polyfunctionalized cage compounds are reported in which derivatives of bis(polynitrohexaazaisowurtzitanyl)methane have both a higher enthalpy of formation and a lower friction sensitivity than CL-20.

The building of new Supramolecular Coordination Containers obtained through the linking of tetrasulfonylcalix[4]arene (3-4H) based transition metal tetra- or trinuclear clusters by succinic acid (suc) as a flexible aliphatic connector possessing high conformational mobility and rotational freedom, produced a variety of three different polynuclear species in the crystalline phase, which were characterized by X-ray diffraction on single crystals and powder. In the case of CoII and NiII cations, the formation of unique chiral-induced isomorphous supramolecular architectures generated by interconnection of dimeric M8-cages with the co-crystallized M(OH)2DMF4 neutral species via H-bonding was observed. Moreover, it was found that, in contrast to what was observed with NiII cations, the use of Cobalt(II) ions in the same multicomponent system, led to the formation of achiral M8-cages which was characterized by the presence of both left- and right-handed succinic acid moieties within the supramolecular entity structure. Finally, the coordination of ZnII cations with 3-4H and succinic acid produced the generation of dimeric M6-cages where two trinuclear [Zn3-3]2+ cationic clusters were bound by two succinic carboxylate units.

Three crystal modifications of phenyl-substituted diphenylphosphoryl thiosemicarbazide (compound (1) and two its solvates with dimethyl sulfoxide (2, 3)) have been obtained and analyzed by the X-ray diffraction (XRD) method. The independent molecules of compounds in crystals 1 and 2 are characterized by the identical (“rolled”) conformation of acyclic framework, stabilized by the intramolecular hydrogen bond N–H⋅⋅⋅O, and their crystals exhibit the formation of an identical chain supramolecular motif, oriented along the axis corresponding to the smallest unit-cell parameter. In crystal 3, the independent molecules are in two different conformations: one is stabilized by an intramolecular hydrogen bond, and the other (“linear”) is due to the molecular adjustment during the formation of a point supramolecular associate with a hydrophilic nucleus and a hydrophobic shell.

The preparation of Ag, Au, and Pd nanoparticles (NPs) by methylviologen (MV2+) was investigated—mediated electrochemical reduction of 1.5 mM Ag(I), Au(I), and Pd(II), respectively, in the presence of poly(N-vinylpyrrolidone) (PVP) and nanocellulose (NC) at the controlled potential of MV·+ radical cation generation in aqueous medium at room temperature. Au(I) and Pd(II) ions were added to the solutions as chloride salts and Ag(I) by in situ dissolving of the Ag-anode during electrolysis. Metal ions are reduced quantitatively to M0 when the theoretical amount of electricity was passed. Dispersion of the Ag anode along with dissolution results in a current yield of Ag0 166%. The result of the synthesis is the nanocomposites of spherical Ag (28 ± 8 nm), Au (10 ± 3 nm), and Pd (5 ± 1 nm) NPs encapsulated in the PVP shell, which are bound on the NC surface and dispersed in the solution volume. The dimensions of the Ag, Au, and Pd crystallites are in the range of values 7.14 ÷ 14.4, 5.7 ÷ 9.0, and 4.5 ÷ 6.2 nm, respectively. The Pd nanocomposite shows a high catalytic activity increasing in time; the Ag and Au nanocomposites are significantly less active in the test reaction of p-nitrophenol reduction with sodium borohydride in an aqueous medium. When cetyltrimethylammonium chloride (CTAC) is added to the nanocomposites, the catalytic reaction rate increases by 57, 2.5, and 1.2 times for Ag, Pd, and Au nanocomposites, respectively.

Nanoparticles (NP) of Au, Ir, Pd, Pt, and Rh are synthesized by benzimidazo[1',2':1,2]quinolino-[4,3-b][1,2,5]oxodiazolo[3,4-f]quinoxaline (BIQOQ)-mediated electrochemical reduction of AuCl, K3[IrCl6], PdCl2, PtCl2, RhCl3, respectively, in the presence of poly(N-vinylpyrrolidone) (PVP) and nanocellulose (NC) at the potential controlled in the region of generation of BIQOQ.– anion radicals in the DMF/0.1 M Bu4NBF4 medium at room temperature. The efficiency of electrosynthesis is shown to be determined by the nature of the substrate to be reduced. K3[IrCl6] is virtually unreducible, whereas the other substrates are reduced to form NP–M. As the theoretical charge is passed, the generated metal is formed in the solution volume rather than as the cathodic deposit. NP–Au particles are formed in the quantitative amount, the mediator is retained in the process. In the other cases, the process consumes from ~50 (Ir, Pd, Pt) to 80% (Rh) of the mediator with the corresponding decrease in the NP–M yield. The synthesis produces individual spherical NP–Pd (4 ± 1 nm) and agglomerates of nanoparticles of gold (78 ± 27 nm), platinum (34 ± 14 nm), and rhodium (33 ± 20 nm) all stabilized in PVP shells. In contrast to the earlier described Ag@PVP nanoparticles which decorated NC in the extremely dense way, these particles are bound only partly with NC. The nanocomposites of Pd, Pt, and Au exhibit catalytic activity in the reactions of reduction of nitroaromatic compounds by sodium borohydride in aqueous media.

Imidazolidin-2-one and 1,3-benzodiazepin-2-one scaffolds are structural motifs of many biologically active compounds. Herein, we report a highly regioselective acid-catalyzed intramolecular nucleophilic cyclization/intermolecular electrophilic substitution reaction sequence of (2,2-dialkoxyethyl)ureas. The reaction benefits from readily available starting materials, a simple workup procedure, moderate to high yields of target compounds, and provides a convenient entry to previously unknown 4-(het)arylimidazolidinones and 5-(het)arylbenzodiazepinones. The proposed mechanism of the reaction is also discussed.

Reaction of the electrochemically in situ from elemental white phosphorus generated phosphine oxide H3 PO in a single electrochemical cell, supplied with lead cathode and aluminium anode, with cyclic ketones (cyclopentanone and cyclohexanone) results in formation of secondary phosphine oxides (bis(α-hydroxycyclopentyl)phosphine oxide 2 a, isolated yield 15 %, and bis(α-hydroxycyclohexyl)phosphine oxide 2 b, isolated yield 12 %) with two α-hydroxycycloalkyl substituents at the phosphorus atom. Bis(α-hydroxycyclopentyl)phosphine oxide reacts with [PdCl2 (COD)] (COD=1,5-cyclooctadiene) to give a new palladium complex trans-[PdCl2 {P(OH)(cyclo-C5 H8 -1-OH)2 }2 ] (3 a, isolated yield 11 %) bearing phosphinous acid as a ligand formed via tautomerization of the phosphine oxide. Finally, the cytotoxicity of the synthesized secondary phosphine oxides on tumor and healthy human cell lines was studied. It was found that at a concentration of 10-6 -10-4 M, phosphine oxides 2 a,b exhibit similar IC50 values for the M-Hela cell line (ca. 50 mM), but are non-toxic for MCF-7 cells. For human alveolar adenocarcinoma cells (A-549), only 2 a is active (ca. 35 mM), while 2 b is not toxic.

The work describes the synthesis of supramolecular and polymer nanocontainers based on carboxylate resorcinarene derivatives. A comparative analysis of their inclusive characteristics toward hydrophilic and hydrophobic substrates was carried out. The obtained containers and silver nanoparticles were used to develop composite materials, and their catalytic activity in the reduction of {tip}-nitrophenol was examined. It was shown that polymer nanocontainers are more ef cient in binding organic substrates, while the supramolecular containers are more suitable for the design of catalytically active composites. The reduction of {tip}-nitrophenol in the presence of nanocomposites based on supramolecular containers proceeds with a higher rate and does not show an induction period.

A family of helical dinuclear copper(I) pyridylphospholane complexes [Cu2L3X]X (X = BF4−, Cl− and Br−) was prepared. The family includes the first examples of this type of complex based on copper(I) chloride and copper(I) bromide. The two isomers typical of this class of compounds, namely head-to-head and head-to-tail complexes, were studied in solution by spectroscopic and optical methods, and in the solid state by X-ray diffraction. Furthermore, the solid-state luminescence of the complexes at different temperatures was studied, and the results were interpreted using quantum-chemical calculations. It was shown that the luminescence of the complexes is attributed to the 3(M + X)LCT transitions.

In this work, we present the synthesis, structural and photophysical characterization, and theoretical study of tetranuclear copper(i) cubane-type Cu4I4 clusters 6-10 with different 10-(aryl)phenoxarsine ligands - 10-(p-fluorophenyl)phenoxarsine (1), 10-(p-ethoxyphenyl)phenoxarsine (2), 10-(phenyl)phenoxarsine (3), 10-(m-fluorophenyl)phenoxarsine (4), and 10-(o-methoxyphenyl)phenoxarsine (5), respectively. The structures of 1-5 were confirmed by NMR spectroscopy, mass spectrometry, elemental analysis and for complexes 6, 7, and 10 by single-crystal X-ray diffraction analysis. The UV/Vis absorption and emission properties were studied and rationalized by DFT and time-dependent DFT calculations. In the solid state, under UV irradiation, all complexes exhibit an intense green emission, which was attributed to a cluster-centered triplet state.

Two new isomorphous ring-like hexanuclear symmetrical coordination species ((2-2H)232M6, M = Co, Ni) presenting a hollow cyclic structure were successfully designed through the molecular recognition between the in situ generated sulfonylcalix[4]arene (3) supported trinuclear clusters and flexible macrocyclic linkers based on the low rim appended calix[4]arene diacid derivative (2-4H) demonstrating a pincer-like shape. The obtained coordination compounds have been characterized from a structural point of view in the crystalline phase revealing the formation of internal hydrophobic voids, passing through the hexameric units, and external voids, resulting from the packing of the complexes in the lattice. A slight structural transformation was evidenced upon air-drying, leading to the closure of external voids caused by the solvent release and also the solvent mobility within the network. The ability of obtained desolvated solid-state hexanuclear species to uptake small volatile molecules like H2O, CH3C(O)CH3, MeOH and EtOH has been investigated by dynamic vapor sorption (DVS) showing their high affinity towards more polarizable molecules.

The two-step electrosynthesis of the nanocomposites of silver nanoparticles supported on CoO–xCoO(OH)2 was carried out in acetonitrile using dissolved oxygen as a reagent in the first step (support synthesis) and a mediator in the second step (silver nanoparticle synthesis). The support and nanocomposite catalyzed the reduction of p-nitrophenol with sodium borohydride in an aqueous medium, and poly(N-vinylpyrrolidone) decreased their catalytic activity.

A series of novel charged disilver(I) complexes with pyridyl-containing phospholanes was synthesized. These complexes were characterized using a range of spectroscopic techniques and single-crystal and powder X-ray diffraction. The complexes demonstrate solid-state near-infrared (NIR) luminescence (765-902 nm) that is unique for dinuclear AgI complexes. Combined spectroscopic/quantum chemical analysis suggests that the NIR luminescence of complexes 4-6 in the solid state is mainly due to crystal packing effects.

New phosphorylated 1,2,4-triazole-3-thiones have been synthesized, and the possibility of their N,Sfunctionalization has been demonstrated. The direction of alkylation of 1,2,4-triazole-3-thiones with ethyl acrylate has been shown to depend on the substituent on the N4 atom.

A new and highly efficient method for the synthesis of 4-(benzimidazol-2-yl)quinolin-2(1H)-ones via the rearrangement of spiroquinoxalinones in moderate-to-excellent yields has been developed. The rearrangement represents a facile approach to medicinally important biheterocyclic compounds. Compared to other methods, the present protocol has a number of advantages such as – cost-effectiveness, avoidance of difficult of access quinolin-2-one and benzimidazole derivatives as reaction partners, and easy accessibility of starting materials, making it a highly practical approach to access various 4-(benzimidazol-2-yl)quinolin-2(1H)-ones.

A combination of tetrasulfonylcalix[4]arene (3-4H) together with a calix[4]arene dicarboxylate derivative 2-4H led, in the presence of MII(NO3)2 (M = Co, Ni, Zn), to the formation of three novel isostructural metallomacrocycles of formula [M3(DMF)2(&mu, 3-H2O)-(2-2H)-3]. The structure of the prepared coordination compounds was studied in the solid state using single crystal/powder X-ray diffraction studies. The X-ray diffraction on single crystal revealed that the structure of the obtained supramolecular complexes is composed of a trinuclear metallic cluster [M3]+6 held between one di-deprotonated molecule of (2-2H)2&minus, offering two carboxylate groups for binding metal cations and one tetra-deprotonated compound 34&minus, where four oxygen atoms, belonging to four deprotonated phenolic moieties and three oxygen atoms coming from three SO2 groups, are coordinated with the cluster core. Thus, an example of an easily reproducible molecular recognition pattern involving two different types of calix[4]arene based ligands, displaying different coordination moieties, and trinuclear metallic clusters, is reported here. In addition, it has been shown that the cone moieties of the calixarene also encapsulate solvent molecules.

Spontaneous resolution of Pasteur&rsquo, s salt was historically the first way to obtain pure enantiomers from the racemate. The current increase in interest in the direct racemates resolution during crystallization is largely due to the opened prospects for the industrial application of this approach. The chiral 3-(3,4-dimethylphenoxy) propane-1,2-diol 1 is a synthetic precursor of practically useful amino alcohols, the enantiomers of which exhibit different biological effects. In this work, it was first discovered that racemic diol 1 is prone to spontaneous resolution. However, the crystallization process is complicated by the existence, along with the conglomerate, of two other crystalline forms. Using the differential scanning calorimetry (DSC) approach, methods have been developed to obtain individual metastable phases, and all identified modifications ((R)-1, (R+S)-1, &alpha, rac-1, &beta, rac-1) were ranked by energy. The IR spectroscopy and powder X-ray diffraction (PXRD) methods demonstrated the identity of the first two forms and their proximity to the third, while &beta, rac-1 is significantly different from the rest. The crystal structure of the forms (R)-1 and &alpha, rac-1 was established by the single crystal X-ray diffraction (SC-XRD) method. Preliminary information on the structure of &beta, rac-1 phase was obtained by the PXRD approach. Based on the information received, the experimental conditions for a successful direct resolution of racemic 1 into individual enantiomers by a preferential crystallization procedure were selected.

International audience; Three zinc based coordination complexes were selectively generated in the crystalline phase using new flexible molecular "tweezers" calix[4]arene derivative ligand decorated with two appended carboxylic moieties and benzyl spacers ((3-4H)). Through the control of the metal/ligand ratio and the sythetic conditions, the coordination sphere around the zinc cations was found to be different, which influenced the nuclearity of the obtained complexes. The mononuclear complex (3-3H)2-Zn(DMF)2 was obtained while two partially deprotonated ligands (3-3H)cap the metallic cation, leading to non tubular "8"shaped structure with metal/ligand ratio equal to 1/2. The dinuclear (3-2H)2-Zn2py4 complex displays a tubular structure with metal/ligand ratio equal to 1/1 where two zinc cations act as linear metal linker between two (3-2H) 2species which adopts a cone conformation. Finally, the third trinuclear coordination complex (3-2H)4-Zn3(OH2) was obtained using (3-4H) and the highly coordinating sulfonylcalix[4]arene (4-4H), exhibiting 3/1/1 metal/3/4 ratio. Thus, it has been demonstrated that under self-assembly conditions, the nuclearity of the new complexes based on zinc cations and calix[4]arene dicarboxylate (3-4H) can be tuned, using different synthetic conditions (nature of solvent, crystallization method, use of a highly coordinating ligand (4-4H).

In this work, we present the synthesis, structural and photophysical characterization, and theoretical study of tetranuclear copper(i) cubane-type Cu4I4 clusters 6-10 with different 10-(aryl)phenoxarsine ligands - 10-(p-fluorophenyl)phenoxarsine (1), 10-(p-ethoxyphenyl)phenoxarsine (2), 10-(phenyl)phenoxarsine (3), 10-(m-fluorophenyl)phenoxarsine (4), and 10-(o-methoxyphenyl)phenoxarsine (5), respectively. The structures of 1-5 were confirmed by NMR spectroscopy, mass spectrometry, elemental analysis and for complexes 6, 7, and 10 by single-crystal X-ray diffraction analysis. The UV/Vis absorption and emission properties were studied and rationalized by DFT and time-dependent DFT calculations. In the solid state, under UV irradiation, all complexes exhibit an intense green emission, which was attributed to a cluster-centered triplet state.

When studying the crystallization in a monotonously varying series of chiral glycerol ethers para-Alk-C6H4-OCH2CH(OH)CH2OH [Alk = Me (1), Et (2), n-Pr (3), and n-Bu (4)] it was established that all except one member form stable crystalline homo- or heterochiral α-phase, depending on the enantiomeric composition (racemic or close to enantiopure) of the feed medium. Propyl derivative 3 falls out of the series and invariably forms stable homochiral crystals. Regardless of the enantiomeric composition, the last two members of the set can form a stable (4) or metastable (3) liquid-crystalline β-phase. For the entire set, regardless of enantiomeric composition, the formation of metastable γ-phase was registered in supercooled melts; according to a number of evidence, the phase is close to an ideal solid solution of enantiomers. It is shown by X-ray diffraction analysis that in crystals of 1–4 samples with high enantiomeric purity, as well as in racemic 3 and 4 samples, a common homochiral guaifenesin-like supra...

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Efficient mediated electrosynthesis of nanocomposite Au@р(MVCA8+-co-St) (~6 nm), in which ultrasmall Au nanoparticles (Au-NP) were bound in nanocapsules of water-soluble nanoparticles of соpolymer р(MVCA8+-co-St) of tetraviologen calix[4]resorcinol (MVCA8+) with styrene (St), was accomplished by the reduction of AuI in aqueous medium. The quanti- tative reduction of AuI was carried out using the theoretically necessary amount of electricity and was not accompanied by the deposition of metal on the electrode. Radical cations of viologen units MV•+ of the molecule р(MVCA4•+-co-St) adsorbed on the electrode and π-dimers MV•+···MV•+ of π-polymers [р(MVCA4•+-co-St)] n deposited on the electrode act- ed as the reducing agents with respect to AuI. During electrolysis, the nanoparticles agglo- merated to 37—50 nm. The nanocomposite particles dispersed in ethanol had sizes of 72±16 nm and also contained Au-NP with sizes of 51±8 and 19±3 nm. The catalytic activity of the nanocomposite in the reduction of p-nitrophenol with sodium borohydride was demon- strated. A similar reduction of AgCl nanoparticles (~250 nm) led to the formation of silver nanoparticles with crystallite sizes in the range of 7—11 nm, the process was inefficient, however, even when using 250% of electricity, an incomplete reduction of AgCl was still observed.

Thiosemicarbazides of diphenylphosphorylacetic acid and their cyclic derivatives have been synthesized. Functionalization of the obtained 1,2,4-triazole-3-thiones with ethyl 2-bromoacetate at the sulfur atom has been carried out, the obtained esters have been transformed into the corresponding hydrazides via hydrazinolysis. Preliminary pharmacological tests of the synthesized compounds have been performed.

A novel clean, one-pot syntheses of 3-arylquinazolin-4(3H)-ones and quinoxalino[2,1-b]quinazoline-6,12(5H)-diones via PPA-mediated coupling of N-(2-carboxyphenyl)oxalamides with arylamines and 1,2-benzenediamines have been developed. Under mild reaction conditions with use of Na2S2O4 the benzimidazo[2,1-b]quinazolin-12-ones were achieved in good yield from 3-(2-nitrophenyl)quinazolin-4-ones.

In this article, we report the synthesis of mono- and bimetallic Pd–Ni nanocomposites supported on a multicharged polymeric matrix for catalytic applications. The morphology and catalytic properties of the composites depend on the Pd–Ni ratio. In the Suzuki–Miyaura coupling reaction, the composite with an equal amount of palladium and nickel is the most active and the reaction occurs within six hours in water at room temperature.

By example of fullerene-mediated electrosynthesis of Ag–C60 nanocomposite in water–o-dichlorobenzene, the possibility of using a liquid–liquid two-phase system for the electro- synthesis of metal nanoparticles has been demonstrated for the first time.

An amphiphilic resorcinarene with ferrocene groups at the lower rim has been applied as both reductant and stabilizer in the synthesis of colloidal silver nanoparticles. The structure of the nanocomposite obtained was investigated by transmission electron microscopy, atomic force microscopy, X-ray powder diffraction, dynamic light scattering, and UV and IR spectroscopy. In the nanocomposite, the silver nanoparticles are stabilized by the multi-layers formed by ferrocene-resorcinarene. The diameter of the nanoparticles is 20–30 nm while the size of the nanocomposite is about 45 nm. The nanoparticles demonstrate good catalytic activity for p-nitrophenol reduction. 40 nanomoles of the silver nanoparticles is sufficient to complete the reduction of p-nitrophenol over ten minutes.

In micellar solutions of sodium dodecyl sulfate, as the concentration of surfactants increases, the spheroid shape of the micelles changes from almost spherical to ellipsoidal with increasing ratio of half-axes ratio, and further the transition to cylindrical micelles occurs. The micelles in an aqueous solution can directly contact (compact aggregates) or be separated from one another by layers of intermicellar medium (periodical colloid structures). In the latter case, the thickness of the layer can significantly exceed the micelle size, and then no mutual correlation in micelle arrangement is observed. According to the data of small-angle X-ray scattering, the relationship between the surfactant concentration and formation of “quasi-crystalline” micellar structure is nonlinear, which can be due to both micelle aggregation processes and nonuniformity of their structure. The possible influence of ordered micellar structures on the diffusion mobility of micelles is shown.

Anilides of 3-aryl-2,3-epoxypropionic acids on treatment with aqueous HBr gave 3-aryl-3-bromo-2-hydroxypropionic acid anilides and (in some cases) 2-bromo-3-hydroxy regioisomers. Cyclization of these products into 3-arylquinolin-2(1H)-ones was studied.

Asphaltenes of four Russian and Kyrgyzstan crude oils were investigated with calorimetry, gas chromatography and X-ray diffraction analysis. It was established that asphaltenes contain waxes. Hydrocarbon composition and the thermal properties of waxes co-precipitated with asphaltenes and isolated by acetone from crudes oils according to the EN 12606-2 method were determined and compared. It was found that n-alkanes C40+ dominate in the waxes co-precipitated with asphaltenes. Waxes in asphaltenes are characterized by high temperature and enthalpy of melting/crystallization. Co-precipitation of high molecular weight waxes with asphaltenes is necessary to consider in order to determine the actual content and composition of asphaltenes and total content and composition of waxes in crude oil more accurately.

Chiral 4-benzoylamino-3-hydroxybutyric acid (1) was recognized in 1930 as the first example of “anomalous racemates” (correct to say, anomalous conglomerates), that is, specific addition compounds formed by different enantiomers in unequal ratio. Through the comparative (racemic against homochiral samples) inspection of the IR spectra, single crystal X-ray diffraction, PXRD analysis, and solubility data we have found that this substance forms normal racemic compound in the solid state, and must be excluded from the very short list of anomalous conglomerates. At the same time homo-1 is dissolved in 25 times better than rac-1, and this feature belongs to another interesting and rare type, namely, “anticonglomerates”. Some of the reasons for this behavior are discussed.

New benzo[b][1,4]diazepine derivatives, which differ only by the substituents in the positions 2 and 4 of the diazepine ring, were synthesized and studied by physicochemical methods. According to the X-ray diffraction data, the benzodiazepine moiety adopts a boat conformation in the crystal. The influence of the nature of the substituents on the type of the resulting supramolecular synthons was investigated.

The interaction of m-bis(3-phenylimidazo[1,5-a]quinoxalin-4(5Н)-on-1-yl)benzene and 3,3'-dibromo-methyl-4-methoxybenzophenone in DMSO or DMF in the presence of t-BuOK or K2CO3, respectively, led to the formation of heterocyclophanes as a result of N,N'-alkylation according to the schemes [1+1] and [2+2] in up to 86% total yield, and the main product from [1+1] N,N'-alkylation was formed in a 57% yield. It was established by X-ray structural analysis that the crystal structure of this product consisted of two independent diastereomeric molecules, and their macroheterocyclic cores were described by an enantiomeric relationship with the accuracy down to the position of the methoxy group in the phenyl fragment.