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Steric structure of fluorinated 2-arylhydrazono-3-oxo esters was studied by 1H, 19F, and 13C NMR spectroscopy and X-ray analysis. It was found that these compounds in the crystalline state and in solutions in acetone-d6, DMSO-d6, and CDCl3 exist as Z isomers with the ester fragment involved in intramolecular hydrogen bond with the hydrazone NH proton. Exceptions are alkyl 2-arylhydrazono-4,4-difluoro-3-oxobutanoates which exist in acetone-d6 as mixtures of Z and E isomers, the former prevailing. Unlike fluorinated analogs, ethyl 2-(4-methylphenyl)hydrazono-3-oxobutanoate in crystal has the structure of E isomer in which intramolecular hydrogen bond is formed between the NH proton and acetyl carbonyl group. The same compound in acetone-d6, DMSO-d6, and CDCl3 gives rise to a mixture of Z and E isomers, the latter prevailing.

2-Aminobenzoic acid 1 reacts with α,β-acetylenic γ-hydroxy nitriles 4 and 5 to afford 2-[(5-iminio-2,2-dialkyl-2,5-dihydro-3-furanyl)amino]benzenecarboxylates 7 and 8 (yield 73–74%), a new class of unnatural amino acids in a peculiar zwitterionic form, having the positive charge transferred to the remote imino group of the dihydrofuranyl substituent. 3- and 4-Aminobenzoic acids 2 and 3 with α,β-acetylenic γ-hydroxy nitriles 4–6 undergo entirely different transformations to deliver the esters of cyanomethylhydroxyalkyl ketones 9–12, which result from the unusually facile esterification of the hydroxyl function and simultaneous hydration of the triple bond. 4-Aminobenzoic acid 3 is found to be an active organic catalyst for the one-pot conversion of α,β-acetylenic γ-hydroxy nitrile 4 to 5-amino-2,2-dimethyl-3(2H)-furanone 13, in 80% yield.

1,8-Bis(dipropylamino)naphthalene and 1,8-di(pyrrolydin-1-yl)naphthalene as well as monoprotonated forms of the latter and of 1,8-di(piperidin-1-yl)naphthalene were structurally analyzed and compared with known data for 1,8-bis(dimethylamino)naphthalene and its protonated form. The N-alkyl groups enlarging the N…N distance (up to ∼2.9 A) and changing the degree of conjugation between the NAlk2 and naphthalene moieties modify in a complex way the basicity (pKa values of conjugated acids) as well as the properties of intramolecular hydrogen bonds both in the solid state and in solution for a set of 1,8-bis(dialkylamino)naphthalenes.

The solvent-free interaction of 2-phenylpyrrole with bromobenzoylacetylene (room temperature) upon their grinding with solid metal oxides (MgO, CaO, ZnO, BaO, Al2O3, TiO2, ZrO2) and salts (CaCO3, ZrSiO4) leads to either the cross-coupling product or the adduct of pyrrole addition to the riple bond of acetylene. The ethynylation is accompanied by the formation of intermediate and side products: E-2-(1-bromo-2-benzoylethenyl)-5-phenylpyrrole and 1,1-di(5-phenylpyrrol-2-yl)-2-benzoylethene. The activity of the metal oxides in the ethynylation reaction falls in the order (in the brackets, the content of 2-benzoylethynyl-5-phenylpyrrole in the reaction mixture is given): ZnO (81%), BaO (73%), Al2O3 (71%), MgO (69%), CaO (50%). The oxides, SiO2, TiO2, ZrO2, and the salts, CaCO3 and ZrSiO4, are inactive in the ethynylation reaction affording only the intermediate adduct, with ZrO2 the isolated yield of the bromoethenylpyrrole reaching 60%. ESR monitoring shows the reaction to start from one electron transfer from pyrrole to acetylene mediated by the oxide surface. The adduct is readily converted on Al2O3 to 2-(benzoylethynyl)-5-phenylpyrrole crystallized mostly as cis-rotamer (X-ray data).

The reactions of 1-methylimidazoline-2-thione and its chemical oxidation product, viz., 2,2′-dithiobis(1-methylimidazolin-2-yl) diiodide, with molecular iodine were studied by UV-Vis spectroscopy. The crystal and molecular structure of the compound of composition [(C3H2N2)(HCH3)S]2(I3)2I2 was established by X-ray diffraction. In the crystal structure, the dications and the triiodide anions form mixed stacks, between which iodine molecules are located. The dications, anions, and iodine molecules are linked by numerous intermolecular interactions to form three-dimensional supramolecular associates.

The reaction of α,β-acetylenic γ-hydroxy nitriles with thiosemicarbazide, under mild conditions (rt, no catalyst, in 1:1 aqueous ethanol, 4–14 h), proceeds chemo-, regio- and stereoselectively to give atypically so far inaccessible tri-functionalized (amino, hydroxyl and thioamide groups) pyrazoles in 53–91% yields. The hydroxyl function is easily protected by using the corresponding acetals of the starting acetylenic hydroxy nitriles.

Thiocarbonohydrazones derived from aromatic aldehydes reacted with 4-phenylbut-3-yn-2-one in aqueous acetic acid (20°C, 2 h) to produce previously unknown N″-[(E-s-cis)-arylmethylidene]-N″′-[(Z-s-trans)-1-methyl-3-phenylprop-2-yn-1-ylidene]thiocarbonohydrazides with high chemo-, regio-, and stereoselectivity. The steric structure of N″-[(E-s-cis)-benzylidene]-N″′-[(Z-s-trans)-1-methyl-3-phenylprop-2-yn-1-ylidene]thiocarbonohydrazide in crystal and in solution was studied by X-ray analysis and IR and NMR spectroscopy.

Fluoroalkyl-containing 1,2,3-trione 2-arylhydrazones react with methylamine in different ways, depending on the substrate structure. Arylhydrazones having a short fluoroalkyl substituent (RF = CF3, HCF2CF2) react at the carbonyl group adjacent to the nonfluorinated substituent to give 3-alkyl(aryl)-2-aryldiazenyl-3-methylamino-1-polyfluoroalkylprop-2-en-1-ones. Arylhydrazones with a long-chain fluoroalkyl group (RF = C3F7 and longer) and a bulky nonfluorinated group take up methylamine molecule at the carbonyl group linked to the fluorinated substituent, and the subsequent haloform reaction yields N-methyl-2-arylhydrazono-3-oxobutanamides. Both types of products are formed in reactions of methylamine with 1,2,3-triketone 2-arylhydrazones having a long fluoroalkyl group and methyl group at the other carbonyl group. Template condensation of fluoroalkyl-containing 1,2,3-trione 2-arylhydrazones with methylamine over Ni(II) template gives bis[3-alkyl(aryl)-1-polyfluoroalkyl-3-methylamino-2-aryldiazenylprop-2-en-1-onato-N,N′]-nickel(II), regardless of the size of the fluoroalkyl substituent. The same complexes and their copper analogs can be obtained by treatment of 3-alkyl(aryl)-2-aryldiazenyl-3-methylamino-1-polyfluoroalkylprop-2-en-1-ones with the corresponding metal salts.

New radical cation salts (BEDT-TTF)2[3,3′-Co(1,2-C2B9H11)2] (1), (BEDT-TTF)2[8-I-3,3′-Co(1,2-C2B9H10)(1′,2′-C2B9H11)] (2), (BMDT-TTF)[3,3′-Co(1,2-C2B9H11)2] (3) and (TMTSF)2[3,3′-Fe(1,2-C2B9H11)2] (4) were synthesized and their crystal structures and electrical conductivities were determined. Compound 4 is isostructural to the earlier reported Co analogue. All the radical cation salts synthesized are semiconductors.

Condensation of ethyl 3-polyfluoroalkyl-3-oxopropionates with excess triethyl orthoformate gave ethyl 3-polyfluoroalkyl-2-ethoxymethylidene-3-oxopropionates which reacted with primary aliphatic, aromatic, and heterocyclic amines to form ethyl 2-alkyl(aryl, hetaryl)aminomethylidene-3-polyfluoroalkyl-3-oxopropionates. According to the X-ray diffraction and IR data, the latter exist in the crystalline state as the corresponding E isomers, while in solution (NMR data), as mixtures of Z and E isomers. Condensation of ethyl 2-ethoxymethylidene-3-oxopropionates with secondary heterocyclic amines (morpholine and pyrrolidine) led to the formation of 2-morpholino(pyrrolidin-1-yl)methylidene-3-fluoroalkyl-3-oxopropionates which were shown to exist as Z isomers both in the crystalline state and in solution.

Fluorinated enaminoketones, a new type of ligands, bearing two independent coordination centers (polyether's and fluorinated enaminoketones fragments) have been obtained. The crystal structure of the Cu(II) complex of 1,5-bis-[2-(4′,4′,4′-trifluoro-1′-methyl-3′-oxo-but-1′-enylamino)-phenoxy]-3-oxapentane (10) has been elucidated by X-ray crystallography. The results obtained show that the complex 10 consists of two crystallographically independent molecules C26H24CuF6N2O5 (A and B), and the metal atom in the complex 10 has four-coordinated arrangement, as a polyhedron with a distorted square with two nitrogen and two oxygen atoms located in corners.

1,2,4-Trimethylquinolinium triiodide (I) and 1-ethyl-2,4-dimethylquinolinium (II) triiodide are synthesized and studied by X-ray diffraction analysis. The layered structures of compounds I and II are formed by mixed stacks of cations and anions. Crystals of compound II consist of two types of anionic chains. The coordinating ability of the corresponding organic iodides toward molecular iodine in chloroform solutions is studied.

According to the 1H, 13C, and 19F NMR data, fluoroalkyl-containing 1,2,3-trione 2-arylhydrazones in CDCl3 exist exclusively, while in (CD3)2CO preferentially, as isomers in which the acyl or aroyl group is involved in intramolecular hydrogen bond. The isomer structure was assigned on the basis of the chemical shifts of the carbonyl carbon atoms and fluorine atoms and carbon-fluorine spin-spin coupling constants JC-F. X-Ray diffraction data showed that 1,2,3-trione 2-arylhydrazones in crystal have the same structure as in CDCl3 solution. Quantum-chemical calculations were performed to rationalize predominant formation of 1,2,3-trione 2-arylhydrazone isomers with a free polyfluoroacyl group.

1-Substituted benzimidazoles are readily annelated regio- and stereoselectively with α,β-acetylenic γ-hydroxyacidnitriles under mild conditions (20–25 °C, no catalyst, no solvent) to form new polyfunctional condensed systems, 4-cyanomethylene-1,3-oxazolobenzimidazoles (30–88 % yield). Unexpectedly, the latter, when chromatographed on neutral Al2O3 at room temperature, undergo a complex multi-position hydrolytic rearrangement involving the cleavage of the imidazole ring to aminophenyl N-substituted formamides with an aminodihydrofuran moiety in the aminophenylsubstituent, N-(2-{[5-amino-2,2-dialkyl-3(2H)-furanylidene]amino}phenyl)-N-substituted formamides, a novel class of highly functionalized pharmacophoric compounds. The results contribute to the basic benzimidazole chemistry and provide for prospective families of drug candidates.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

The crystal structures of the chelates NiIIL (L2− are the N,N′-(o-phenylene)-bis[4-(4-methylphenyl)hydrazono-3-oxo-1,1,2,2-tetrafluorononane-5-iminate], N,N′-ethylene-bis[3-(4-methylphenyl)hydrazono-4-oxo-5,5,6,6,7,7,8,8-octafluorooctane-2-iminate], or N,N′-ethylene-bis(4-hydroxy-5,5,6,6,7,7,8,8-octafluoro-3-octene-2-iminate) anions) were studied by X-ray diffraction. Magnetic measurements and ESR spectroscopic studies revealed the appearance of paramagnetism due to a tetrahedral distortion of the coordination unit and also the unusual behavior of the effective magnetic moment at low temperatures.

New radical cation salts (TMTSF) 2 [3,3′-Co(1,2-C 2 B 9 H 11 ) 2 ] ( 1 ), (TTF)[3,3′-Co(1,2-C 2 B 9 H 11 ) 2 ] ( 2 ) and (ET)[3,3′-Co(1,2-C 2 B 9 H 11 ) 2 ] ( 3 ) were synthesized and their crystal structures and electrical conductivities were determined. Compound 1 has layered structure with conducting stacks of the TMTSF cations, whereas compounds 2 and 3 contain separated pairs of fulvalenium cations. Conductivity of crystals 1 at room temperature was found to be 15 Ohm −1 cm −1 , that is the maximum value found for fulvalenium metallacarborane salts.

New reactive dyes, 2-arylazo-1-vinylpyrroles, have been synthesized in 52–94 % yield by a modified azo coupling of readily accessible 1-vinylpyrroles with arenediazonium hydrocarbonates in aqueous ethanol (≈3:1) at 0 °C. The λmax values for the UV/Vis absorption of the dyes ranges from 377.8–480.6 nm with log ϵ = 4.11–4.99, and this strongly depends on the substituent structure both in the pyrrole and the benzene ring, and is indicative of highly polarizable and tunable chromophores. X-ray, 1H NMR spectroscopic and quantum chemical studies [B3LYP/6-311 (d,p)] show the E,anti,anti isomer of the dyes to be the most stable under normal conditions. The dyes are reversibly protonated and complex to BF3 with a color change. Their copolymerization across the vinyl group affords intrinsically colored copolymers. They have also been shown to act as good ligands in the Pd-catalyzed Heck alkene arylation. Thus, the properties of the novel dyes are promising for creating new molecular switches, memory and recording devices, acid-base and metal sensors, as well as transition-metal complex catalysts.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

Two anion-radical salts (ARS) of 7,7′,8,8′-tetracyanoquinodimethane (TCNQ) – ( N -Me-2-NH 2 -Pz)(TCNQ) 2 and ( N -Me-Tetra-Me-Pz)(TCNQ) 2 ( N -Me-2-NH 2 -Pz, N -methyl-2-amino-pyrazinium-; N -Me-Tetra-Me-Pz, N -methyl-tetra-methyl-pyrazinium-ions) – were synthesized and characterized. Both salts (ARS) were found to be semiconductors with a room-temperature conductivity of 3.8 × 10 −5 and 1.93 × 10 −2 Ω −1 cm −1 , respectively. For both salts a layered structure of cations and anion-radicals was discovered, where layers composed of cations alternate along the b -axis with the layers containing TCNQ anion-radicals. The cations in the ( N -Me-2-NH 2 -Pz)(TCNQ) 2 form pairs bonded by strongly shortened 1.97 (2) A intermolecular hydrogen N(1)…H(3a) links.

The structure of 2,3,4,6-tetra( O -vinyl) methyl-α- d -glucopyranoside, a new powerful carbohydrate synthon has been studied by 1 H and 13 C NMR, IR, MS and X-ray methods. The 13 C– 13 C spin–spin coupling constants were measured to conclude that s - trans -conformation is preferable for the vinyloxy groups at C2, C3 and C4 atoms, while s - cis -conformation is inherent in the vinyloxy group at C6 atom. The data obtained are indicative of identical stereochemical structure of this compound both in crystals and in solution.

Polyhaloalkyl-substituted chromones, gamma-pyrones, and beta-furanones react with salicylaldehydes in the presence of piperidine to give a wide variety of fused 2H-chromenes in good yields. This novel annulation reaction presumably proceeds by a tandem intermolecular oxa-Michael addition and subsequent intramolecular Mannich condensation.

A consecutive aromatic nucleophilic substitutions of hydrogen in 1,2,4-triazine 4-oxides and an aza Diels−Alder reaction is a versatile route to carborane-functionalized bi- and terpyridines and their 1,2,4-triazine analogues. The heterocycles facilitate deboronation of the substituted carboranes, and the carborane moiety has a significant influence on the coordination properties of the ligands as well.

2-(2-Cyano-1-ethylthioethenyl)pyrroles easy exchange their ethylthio group for hydroxyl (NaOH, H2O–methanol, 40–45 °C, 1 h) to give 2-(2-cyano-1-hydroxyethenyl)pyrroles, a new family of stable enols, in 50–94% yields. The vinylic nucleophilic substitution proceeds at the double bond of both the starting pyrroles and their cyclic isomers, 3-iminopyrrolizines. X-ray structure analysis and NMR spectra show the enols to be stabilized by exceptionally strong intramolecular H-bonding.

Three charge-transfer salts of [Ni(dmid)2]− (dmid: 1,3-dithiol-2-one-4,5-dithiolate)—TMTTF[Ni(dmid)2], TTFx[Ni(dmid)2] and ETx[Ni(dmid)2] (TMTTF: tetramethyl-tetrathifulvalene, TTF: tetrathifulvalene, ET: bis(ethylenedithio)-tetrathiafulvalene) are prepared and characterized. The TMTTF[Ni(dmid)2] complex has a structure with mixed packs is formed by cations and anions, which alternate each other with subsequent shift. This compound is semiconductor with the room-temperature conductivity of 2.2 × 10−3 Ω−1 cm−1. The TTFx[Ni(dmid)2] and ETx[Ni(dmid)2] complexes have a highest conductivity: σRT 1.86 and 0.54 Ω−1 cm−1, respectively.

1-Dimethylamino-2,7-dimethoxy-8-methylamino-3,5-dinitronaphthalene and 1,2,4-tri-bromo-6-dimethylamino-5-methylaminoacenaphthylene containing the N,N,N′-trimethyl-1,8-diaminonaphthalene fragment with the substituted aromatic ring were studied by X-ray diffraction. Both systems are stabilized by an intramolecular hydrogen bond. The characteristics of the latter are determined by the influence of either the ortho substituents or the peri-annelated five-membered ring. In the former case, the intramolecular hydrogen bond is substantially shortened (N...N, 2.628(5) A) due to the “buttressing effect” of the o-OMe groups, whereas the peri-dibromoethylene bridge and the Br substituent at position 4 cause a substantial elongation of the intramolecular hydrogen bond (N...N, 2.75(2) and 2.76(1) A) in the latter case.

Bis(2-phenylethyl)phosphine selenide was obtained with 86% yield from bis(2-phenylethyl)phosphine and selenium. XRD, IR, UV, and multinuclear NMR spectroscopic studies revealed that the phosphorus atom in the bis(2-phenylethyl)phosphine selenide molecule is four-coordinated irrespective of the phase state (crystals or solution).

The coupling of trifluoromethylated 1,3-diketones with (het)aryldiazonium chlorides results mainly in the formation of 1,2,3-triketones 2-(het)arylhydrazones while using hetarylamine with a NH-group at the α-position of the heterocycle as the diazonium component gives 4,7-dihydroazolo[5,1-c]triazines due to cyclization at the trifluoroacetyl fragment. Trifluoromethylated 1,2,3-triketones 2-(het)arylhydrazones and 7-hydroxy-4,7-dihydroazolo[5,1-c]triazines react regio-selectively with methyl hydrazine and phenyl hydrazine to form 3-CF3-pyrazoles. The long-range coupling constants (JF-H) of 1-methylpyrazoles and the chemical shifts of trifluoromethyl groups in the 19F NMR spectra can be used for the determination of regio-isomeric structures of mono(trifluoromethyl)-substituted pyrazoles. 2-(Het)arylhydrazones and 4,7-dihydroazolo[5,1-c]triazines with two trifluoromethyl substituents afford the mixtures of cis- and trans-azopyrazoles in the reactions with hydrazines.

A new radical cation salt based on bis(ethylenedioxy)tetrathiafulvalene (BEDO) with the planesquare anion Ni(CN) 4 2− is synthesized. The molecular and crystal structures of the radical cation salt are determined, and the conducting properties are investigated. In the structure, the BEDO radical cations have a β″-type packing. It is shown that the temperature dependence of the conductivity of (BEDO)4Ni(CN)4 · 4CH3CN crystals exhibits metallic behavior.

4-Hydroxy-4-methyl-2-pentynonitrile reacts with aniline, N-methylaniline, and 2-naphthylamine under mild conditions (20–80°C) to afford the corresponding 4-arylamino-2-(2-imino-5,5-dimethyl-2,5-dihydro-4-furylimino)-5,5-dimethyl-2,5-dihydrofurans in one preparative step. According to the X-ray diffraction data, both imino groups in the products have syn configuration with respect to the ring oxygen atom.

The new radical cation salt based on bis(ethylenedithio)tetraselenafulvalene (BETS) with the square planar [Ni(CN) 4 ] 2− anion was synthesized by electrocrystallization: (BETS) 4 ·Ni(CN) 4 . X-ray analysis, electron transport, magnetotransport and electronic band structure calculations are presented and discussed.

The first examples of facile hydrothiophosphorylation of organyl vinyl sulfoxides are described. Nucleophilic addition of P,S-ambident secondary phosphine sulfides 1 and 2 to organyl vinyl sulfoxides 3-6 with potassium hydroxide at room temperature proceeds chemo- and regioselectively to give the corresponding bis(2-organylethyl)[2-(organylsulfinyl)ethyl]phosphine sulfides 7a-e in high isolated yields.

Complex formation in systems containing 3-carboxypropyltriphenylphosphonium or tetraphenylphosphonium bromide, molecular iodine, and chloroform solution was compared. The maximum number of iodine molecules coordinated by bromides in the solution was established by spectrophotometric method using a function of average iodine number and the stability constants of the complexes were determined. The diiodobromide [(C6H5)4P]BrI2 was studied by X-ray diffraction analysis. The ab initio calculations were performed for [Y(R)4]I3 (Y = N, P, As; R = CH3, C6H5). The obtained experimental data and the correlations with the results of quantum-chemical calculations revealed that the tetraphenylphosphonium cation binds diiodobromide anions through the terminal halogen atoms with equal probability.

Complexation in the N-ethylquinolinium iodide–molecular iodine system in a chloroform solution is studied. The stability constant of N-ethylquinolinium triiodide (I) is determined by spectrophotometric methods of stoichiometric dilution using the average iodine number function. Compound I with the [C9H7NC2H5]I3 composition is studied by X-ray diffraction analysis. The crystal structure is formed by alternating layers of cations arranged by the “ladder” type and triiodide anions with equalized interatomic distances. The triiodide anions are linked to form chains through strongly shortened intermolecular contacts.

This work reports on the synthesis, conducting properties, crystal and electronic structures of two new molecular conductors based on EDT with anionic complexes of rare-earth elements, (EDT)2[Ho(NCS)4(H2O)4] and (EDT)3[Y(NO3)5]. The salts are characterized by a β-packing type of donors in the conducting layers. (EDT)2[Ho(NCS)4(H2O)4] is a metal down to 100 K and (EDT)3[Y(NO3)5] shows semiconducting properties. The relationship between the conductivity behavior and the crystal structure of the two salts is rationalized on the basis of tight-binding band structure calculations.

A novel radical cation salt based on of the donor (4,5-ethylenedithio-4′,5′-vinylenedithio)tetrathiafulvalene (EVT) with the square planar anion Pt(CN)42− has been synthesized: (EVT)4·[Pt(CN)4] (1). According to the X-ray analysis its crystal structure includes EVT cation layers alternating with anion layers along the a-axis of the unit cell. The radical cation layer is formed by EVT stacks with β-packing type, the donors in stacks are tetramerized. The EPR spectra of a plate-like crystal of (EVT)4·[Pt(CN)4] salt shows a very weak signal with typical parameters of TTF derivative. The room temperature conductivity of salt 1 is 8×10−2 Ω−1 cm−1 and the temperature dependence of the conductivity exhibits semiconducting character.

Complexation in the 3-carboxypropyltriphenylphosphonium bromide–molecular iodine system in chloroform was studied. The maximum number of iodine molecules coordinated by 3-carboxypropyltriphenylphosphonium bromide was established by the spectrophotometric method using a function of the average-iodine number, and the stability constant of the complex was determined. The [(C6H5)3P(CH2)3COOH]BrI2 diiodobromide was studied by X-ray diffraction analysis. The characteristic feature of the crystalline salt was the formation of dimer associates: anionic associates were formed due to the Br···Br intermolecular interactions and cationic associates were formed due to the O···H–O hydrogen bonds. The data obtained were correlated to the results of quantum-chemical calculations.

On treatment of 2,7-dilithio- (6a) and 2,7-bis(bromomagnesio)- (6b) naphthalenes with a number of electrophiles, new "proton sponge" derivatives 7a-e,g, containing iodo, methylthio, trimethylsilyl, methyl, n-butyl, and ethoxycarbonyl groups in ortho-positions to dimethylamino groups, have been synthesized. The investigation of their molecular structure, spectral characteristics, and basicity reveals that the latter is mainly determined by two groups of factors: (1) the polar effect of ortho-substituents and (2) the so-called "buttressing effect" representing the complex combination of various sterical interactions of ortho-substituents with dimethylamino groups in corresponding bases and cations. A contradictory directionality of these interactions strongly reduces the importance of the buttressing effect in the case of compounds with bulky ortho-substituents, which is most clearly displayed in the absence of any relationship between the size of ortho-substituents and the basicity. On the contrary, for proton sponges having in ortho-positions the electron-donating groups with lesser steric demands, both the buttressing and the polar effects act in the same direction. This is the reason for the exceptionally high basicity of 2,7-dimethoxy- (2) and tetrakis(dimethylamino)- (3a) naphthalenes. It has been found that bis(trimethylsilyl)-bis(dimethylamino)naphthalene 7d has an in-out configuration of the NMe2 groups in the solid that is the first example of its kind in the series of naphthalene proton sponges. The origin of a yellow coloring of 2,7-disubstituted proton sponges is also discussed.

New bis(ethylenedithio)tetraselenafulvalene (BETS) based radical cation salts with chloromercurate anions have been prepared by electrocrystallization. The salt (BETS)4Hg3Cl8 is metallic down to 32 K, at lower temperatures the resistance grows smoothly being lower than the starting value. The salt (BETS)4Hg2Cl6(C2H5Cl)x, x∼1, undergoes a metal-to-insulator transition near 100 K. The crystal structure of (BETS)4Hg3Cl8 is formed by the layers of the BETS radical cations of the κ-type packing and inorganic layers composed of the [Hg2Cl6]2− anions and the HgCl2 molecules.

The first europium(iii) pyridylphosphine complex, [Eu(N,N’,N”-2-Py3P)(NO3)3] was prepared by the reaction between Eu(NO3)3.6H2O and tris(2-pyridyl)phosphine; its structure was characterized by single-crystal X-ray diffraction.

New radical cation salt of bis(ethylenedithio)tetrathiafulvalenium and iron bis(dicarbollide) [BEDT-TTF] 2 [3,3′-Fe(1,2-C 2 B 9 H 11 ) 2 ] ( 1 ) has been synthesized. The crystal structure of 1 has been determined by single-crystal X-ray diffraction method found to be isostructural to the known Co and Cr analogues. The electric conductivity measurement in the range of 110 ÷ 296 К shows that 1 is semiconductor with the room temperature conductivity σ 293 = 1.5 × 10 −2 Ω −1 cm −1 , that is higher than in the Cr analogue and lower than in the Co analogue. The measurement of magnetic susceptibility in the range of 2 ÷ 300 K revealed that 1 is paramagnetic with the absence of significant interactions between the organic radical cations and the paramagnetic anions.

The new molecular conductors with some rare-earth metal-complex anions (ET)5[M(NCS)6NO3]·C2H5OH (M=Dy (1), Y (2), Ho (3)) and (TMTSF)3[Y(NO3)5]·2C6H5Cl (4) as well as a new low-temperature modification of tetra-n-buthylammonium dysprosium(III) complex, (Bu4N)3[Dy(NCS)4(NO3)2] (5) used for the preparation of salt 1 were synthesized and studied by X-ray crystallography at 295 and 110 K. Salts 1–3 have a layered crystal structure with a new packing type of the radical cation layers, called an ω-type. Electronic structure calculations for the compounds 1–3 showed that the paired ET molecules have a positive charge +1 and the single ET molecules are neutral. The directions of the TMTSF stacks in the neighboring organic layers of 4 are practically perpendicular so that salt 4 can be regarded as a precursor of 2D conductors formed by mutually perpendicular directions of conductivity.

A new room-temperature metallic modification of the well known radical cation salt (ET)2[KHg(SCN)4] has been prepared by electrochemical oxidation of ET. Its crystal and electronic structure have been examined at 110 K. The salt has a layered structure in which the conducting layers are characterized by the δ-type packing.

The complex formation in the system bis[2-(trimethylammonio)ethyl] succinate diodide-iodine involves no more than two iodine molecules. The crystal structure of the salt [(CH3)3N(CH2)2OCOCH2]2(I3)2 is formed by layers of inorganic anions (I3 -) and organic dications (centrosymmetric dications {[(CH3)3N · (CH2)2OCOCH2]+}2), evenly alternating along the a axis. The crystal structure of the salt [(CH3)3N(CH2)2·OCOCH2]2(I3)2(I2)0.5 is formed by organic and inorganic layers evenly alternating along the [011] diagonal, with a centrosymmetric iodine molecule.

2-Alkylcyclohexanones react with arylacetylenes (KOH/DMSO, 100 °C, 1 h) to afford unexpectedly hexahydroazulenones in 34–50% yields and ca. 100% diastereoselectivity (instead of the expected acetylenic alcohols), the minor products being isomeric arylethenyl ketones.

The oxidative cross-coupling between 4-hydroxy-6-methyl-2-pyrone or 3-hydroxy-2-methyl-4-pyrone and secondary phosphine chalcogenides proceeds in CCl4/Et3N under mild conditions (20–52 °С, 0.75–10 h) through the hydroxyl group to give O-(6-methyl-2-oxo-2H-pyran-4-yl) diorganylphosphinochalcogenoates or O-(2-methyl-4-oxo-4H-pyran-3-yl) diorganylphosphinochalcogenoates, in high yields.

The paper describes the model of collective development of knowledge bases (KB), based on ontologies, and knowledge base editor that implements this model. In addition, the paper discusses the requirements for knowledge base editors that support collaborative KB building. The model proposed uses asynchronous editing mode as default and knowledge base version control system. The model supports integration of notifications and discussions into the development process, as well as the presence of the flexible roles and permissions management system to support groups of developers and experts with various levels of ontological competence and areas of expertise. The implementation of this model in KB editor integrated into the thematic intelligent scientific Internet resource (ISIR) is described. Collaborative KB building is supported by version control subsystem that constantly monitors the consistency of the knowledge base, and by the notification subsystem intended to make development transparent for users and to integrate the discussions to the development process.

A new organic semiconductor with trinitroresor-cinol as the anion, (TMTTF)2(C6H2N3O8) (1) (TMTTF: tetramethyltetrathiafulvalene), has been synthesized and its crystal structure has been investigated at room and low temperatures (295 and 110 K). The crystal structure of 1 is formed by one-dimensional stacks of cation-radicals (TMTTF)+1/2 separated by trinitroresorcinol anions (C6H2N3O8)–. This novel salt reveals semiconducting properties. Tight-binding band structure calculations for 1 have been carried out in order to understand the charge distribution among the different donors.

A new radical cation (ET) 5 [Dy(NCS) 6 NO 3 ]·C 2 H 5 OH salt was prepared by electrochemical oxidation of ET in a chlorobenzene–ethanol solution. Its crystal structure and conducting properties were examined. The salt has a layered crystal structure with a basically new packing type of the radical cation layer, which was called an ω-type. Resistance studies reveal a semiconducting nature of this salt.

A new molecular semiconductor, (Doet)2ReO4(Doet is (1,4-dioxanediyl-2,3-dithio)ethylenedithiotetrathiafulvalene), is synthesized and examined by X-ray diffraction analysis. The crystal structure of (Doet)2ReO4is formed by [Doet]+1/2layers with isle [ReO4]–anions located between them. The Doet radical cations from the adjacent layers are linked by intermolecular hydrogen interactions of the O···H type.

The molecular complex C60·2[(Ph3P)AuCl] (1) was synthesized. The crystal and molecular structure of1 was established by X-ray diffraction analysis. At room temperature, the [60]fullerene molecules in complex1 are ordered due to π—π interactions between C60 and the phenyl rings of the chloro(triphenylphosphine)gold(1) molecules. The satellite structure, which accompanies the Cls photoelectron peak of complex1, is indicative of a partial suppression of a channel of losses due to π→π transition in the phenyl ring. The 1R spectral data indicate that either a charge is absent or the charge transfer to the fullerene molecule is negligible.