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The C-methylthio derivatives of cobalt bis(dicarbollide) were synthesized by reaction of anhydrous CoCl2 with nido-carborane [7-MeS-7,8-C2B9H11]− and isolated as a mixture of rac-[1,1′-(MeS)2-3,3′-Co(1,2-C2B9H10)2]− and meso-[1,2′-(MeS)2-3,3′-Co(1,2-C2B9H10)2]− isomers. The structures of both isomers were studied using DFT quantum chemical calculations. The most preferable geometry of rotamers and the stabilization energy of C-methylthio derivatives of cobalt bis(dicarbolide) were calculated. The (BEDT-TTF)[1,1′-(MeS)2-3,3′-Co(1,2-C2B9H10)2] salt was prepared and its structure was determined by single crystal X-ray diffraction. The cisoid conformation of the rac-[1,1′-(MeS)2-3,3′-Co(1,2-C2B9H10)2]− anion is stabilized by short intramolecular CH⋯S hydrogen and BH⋯S chalcogen bonds between the dicarbollide ligands, that is in good agreement with the data of quantum chemical calculations.

The radical-cationic salts based on tetrathiafulvalene derivatives and bis(dicarbollide) transition metal complexes [3,3′-M(1,2-C2B9H11)2]− (M = Co, Ni, Fe, Cr) are promising for the creation of new molecular conductive materials due to the almost unlimited possibilities of their modification. The relationships between the properties of both components of the cation-radical salts, their crystal structure, and electrical and magnetic properties have been analyzed on the basis of the literature and our own data. The effect of various substituents in metallacarborane anions on the structure and physical properties of their radical cation salts based on tetrathiafulvalene and its derivatives has been revealed. Data on the structure and properties of the radical cation salts with other borate anions are presented for comparison.

The first molecular conductors based on bis(1,3-propylenedithio)tetrathiafulvalene and transition metal bis(dicarbollides) (BPDT-TTF)[3,3′-Сr(1,2-C2B9H11)2] (1) and (BPDT-TTF)[3,3′-Сo(1,2-C2B9H11)2] (2) were synthesized and their crystal structures were determined by X-ray analysis. The electric conductivity measurements revealed that these compounds are semiconductors at room temperature.

The synthesis of a radical-cation salt based on a derivative of tetrathiafulvalene, (ET)2[3,3′-Cr(1,2-C2B9H11)2] (ET = bis(ethylenedithio)tetrathiafulvalenium), was accomplished by electrochemical anodic oxidation of ET in the presence of (Me4N)[3,3´-Cr(1,2-C2B9H11)2] in the galvanostatic regime. An electric conductivity σ (293 K) = 7 × 10−3 Ohm−1 cm−1 with semiconductor activation energy Ea ≅ 0.1 eV in the range of 127–300 K was observed. The crystal structure of (ET)2[3,3′-Cr(1,2-C2B9H11)2] was determined by X-ray diffraction at 173 K, revealing the presence of structural tetramers in radical-cation stacks. The magnetic properties of the complex were investigated in the temperature range 1.8–300 K using magnetometry and EPR, showing that the magnetic structure of (ET)2[3,3′-Cr(1,2-C2B9H11)2] consists of two independent magnetic subsystems. Cation radicals form a rectangular magnetic lattice in the ab-plane with significant antiferromagnetic exchange interactions. The chromium bis(dicarbollide) anions are characterized by unusually strong positive zero-field splitting of the Cr(III) ions, which was confirmed by ab initio calculations.

The new molecular conductors based on unconventional tetrathiafulvalene π-donors 4,5-ethylenedithio-4′,5′-(2-oxa-1,3-propylenedithio)tetrathiafulvalene (EOTT) and bis(1,3-propylenedithio)tetrathiafulvalene (BPDT-TTF) and metallacarborane anion [8,8′-Cl2–3,3′-Fe(1,2-C2B9H10)2]− were synthesized and their crystal structures were determined by single crystal X-ray diffraction. The electric conductivity study proved that both compounds (EOTT)2[8,8′-Cl2–3,3′-Fe(1,2-C2B9H10)2] and (BPDT-TTF)2[8,8′-Cl2–3,3′-Fe(1,2-C2B9H10)2] are semiconductors at room temperature.

New radical-cation salts based on bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF or ET) were synthesized: (ЕТ)2[8,8′-Br2-3,3′-Fe(1,2-C2B9H10)2] (1) and (ЕТ)[8,8′-I2-3,3′-Fe(1,2-C2B9H10)2] (2). Their crystal structures were studied by X-ray analysis, electroconducting and magnetic properties were measured in a wide temperature range. Salts (1) and (2) appeared to be the first radical-cation salts with [8,8′-I2-3,3′-Fe(1,2-C2B9H10)2]- and [8,8′-Br2-3,3′-Fe(1,2-C2B9H10)2]- anions, respectively. In the literature [8,8′-I2-3,3′-Fe(1,2-C2B9H10)2]- and [8,8′-Br2-3,3′-Fe(1,2-C2B9H10)2]- anions are presented for the first time. Salts (1) and (2) were found to be paramagnetic. Their room temperature conductivities were 2 and 1·10−6 Ohm−1cm−1, respectively.

The

A new radical cation salt of bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) with iron(III) bis(1,2-dicarbollide) 8,8´-dichloro derivatives, that is (BEDT-TTF)2[8,8´-Cl2-3,3´-Fe-(1,2-C2B9H10)2], was synthesized. Its electroconducting and magnetic characteristics were studied, molecular and crystal structures were determined. The electroconductivity of crystals at room temperature was σ293 ~5 Ω–1 cm–1, which is close to the corresponding value for the salt of cobalt bis(1,2-dicarbollide) dichloro derivative and is considerably higher than the electroconductivity of a similar salt of unsubstituted iron bis(1,2-dicarbollide). The measurements of magnetic susceptibility at 2—300 K showed that this salt is paramagnetic.

The new radical cation salts based on transition metal bis(dicarbollides) with dibenzotetrathiafulvalene (DBTTF) donors (DBTTF)[3,3′-Fe(1,2-C2B9H11)2] (1) and (DBTTF)2[3,3′-Cr(1,2-C2B9H11)2] (2) were synthesized and their crystal structures were determined by single crystal X-ray diffractions. The electric conductivity measurements revealed that these compounds are semiconductors at room temperature and the conductivity of (DBTTF)2[3,3′-Cr(1,2-C2B9H11)2] is ~500 times higher than that of its BEDT-TTF analogue.

Radical cation salts based on derivatives of tetrathiafulvalene and sandwiched transition metal bis(dicarbollide) anions are of great interest in the development of new molecular conducting materials. The data on their synthesis, crystal structure, and electrical and magnetic properties were reviewed. The effect of various substituents in the metallacarborane anion on the structure and physical properties of their tetrathiafulvalene-based radical cation salts was analyzed. Relationships between the crystal structure and properties of the tetrathiafulvalene-based radical cation salts containing sandwiched transition metal bis(1,2-dicarbollide) anions are discussed.

Tautomeric forms of 3-formyl-4-hydroxycoumarin arylhydrazones were studied by 1H and 13C NMR spectroscopy, as well as X-ray structural analysis. These compounds were shown to exist primarily in the 4-hydroxycoumarin form both in DMSO solution, as well as in gas phase; the chroman-2,4-dione form was a minor component. According to X-ray structural analysis data, solid 3-formyl-4-hydroxycoumarin phenylhydrazone exists in the 4-hydroxycoumarin form.

Four new [(NHC)RhCl(COD)] (NHC = perimidin-2-ylidene; COD = 1,5-cyclooctadiene) rhodium complexes (4a–c and 5a) have been prepared by the reaction of [Rh(μ-OMe)(COD)]2 with perimidinium bromides (2a–c and 3a). The halogen exchange, abstracted from 1,2-dichloroethane was observed during the reaction and [(NHC)RhCl(COD)] complexes were obtained instead of [(NHC)RhBr(COD)]. All ligand precursors and complexes have been fully characterized by 1H, 13C NMR, IR spectroscopy, elemental analysis and mass spectroscopy. X-ray diffraction studies on single crystals of 4a and 5a confirm the square planar geometry. The υ(CO) values of [(NHC)RhCl(CO)2] complexes (6a–c and 7a) revealed that the NHC ligands are not good σ-donors. Transfer hydrogenation (TH) reaction of aliphatic and aromatic ketones has been comparatively studied by using complexes 4a–c and 5a as catalysts.

Radical cation salts of bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) and bis(methylenedithio)tetrathiafulvalene (BMDT-TTF) with the 8,8′-dichloro derivative of cobalt bis(1,2-dicarbollide) (BEDT-TTF)2[8,8′-Cl2-3,3′-Co(1,2-C2B9H10)2] (1) and (BMDT-TTF)4[8,8′-Cl2-3,3′-Co(1,2-C2B9H10)2] (2) were synthesized and their crystal structures and electrocon-ducting properties were determined. The synthesized radical cation salts are semiconductors with the conductivity σ293 = 1.5 and 2.0 Ohm−1 cm−1, respectively. A decrease in the size of the substituent in a series of (BEDT-TTF)2[8,8′-X2-3,3′-Co(1,2-C2B9H10)2] and (BMDT-TTF)4[8,8′-X2-3,3′-Co(1,2-C2B9H10)2] (X = I, Br, Cl) results in the compression of the anion sublattice of the crystal and compaction of the radical cation packing of the conducting layer, which, in turn, increases the conductivity of the crystals.

Tris(2-pyridyl)phosphine chalcogenides Py3P=X (X = O, S, Se) react with PdCl2 or Li2PdCl4 to give the chelate complexes cis-[Pd(N,N’-Py3P=X)Cl2] in which PdII ion is square-planar coordinated to two pyridine nitrogen atoms of the ligand (κ2-N,N’).

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.

Genuine organic anion-radical salt (N-Me-2,6-di-Me–Py)(TCNQ) 2 with pyridine-based cation was synthesized and its crystal structure was resolved. The DC magnetic susceptibility was measured in temperature range from 2 K to 300 K in magnetic fields 10 mT, 100 mT and 1 T. Zero field cooling (ZFC) and field cooling (FC) modes were used. The results were studied in terms of one-dimensional magnetic models and we have found that the most suitable of them is an antiferromagnetic linear Heisenberg S = 1/2 system with small amount of free spins. An additional peak observed at low temperatures can be explained by an interchain coupling between free chain-end spins.

New radical cation salts (BEDT-TTF)2[anti-7,7′:8,8′-bis(dithio)bis(7,8-dicarba-undecaborate)] and (TMTTF)2[anti-7,7′:8,8′-bis(dithio)bis(7,8-dicarbaundecaborate)] were obtained by electrocrystallization from solution of bis(ortho-carboranyl-1,2-dithiolate)cobalt(II) complex (Me4N)2[Co(1,2-S2C2B10H10)2] and BEDT-TTF or TMTTF, respectively, in acetonitrile – 1,1,2-thrichloroethane. The process is accompanied with the complex demetallation, partial deboronation of the carborane cage and oxidation of dithiolate to cyclic bis(disulfide). X-ray crystal structures and electrical conductivities of the compounds synthesized were determined.

A technique is proposed for directed synthesis of 6,11-dichloro-9-dimethylthio-7,8-dicarba-nido-undecaborane [6,11-Cl2-9-SMe2-7,8-C2B9H9]. Single-crystal X-ray diffraction is used to identify the molecular and crystal structure of the compound.

Radical cation salts based on derivatives of tetrathiafulvalene and sandwiched transition metal bis(dicarbollide) anions are of great interest in the development of new molecular conducting materials. The data on their synthesis, crystal structure, and electrical and magnetic properties were reviewed. The effect of various substituents in the metallacarborane anion on the structure and physical properties of their tetrathiafulvalene-based radical cation salts was analyzed. Relationships between the crystal structure and properties of the tetrathiafulvalene-based radical cation salts containing sandwiched transition metal bis(1,2-dicarbollide) anions are discussed.

Imidazo(4,5-b)pyridines are readily annelated (45-50 o C, 24-30 h, MeCN) with cyanoacetylenic tertiary �-alcohols to give stereoselectively functionalized 1,3-oxazolo(3,2-a)imidazo(4,5- b)pyridines in 50-88% yields. The adducts undergo a facile stereoselective hydrolytic domino rearrangement to functionalized derivatives of 2,3-diaminopyridines.

Ethyl isonicotinate reacts with tertiary cyanoacetylenic alcohols under exceptionally mild conditions (room temperature, without catalyst or solvent) to afford novel polycondensed heterocyclic systems, 4,15-dioxa-7,12-diazapentacyclo[9.5.2.02,10.03,7.012,16]octadeca-8,17-dienes, in 30–68% yields. This tandem cyclization is regio- and stereospecific. Despite several asymmetric carbons (up to six) being present in the molecules, only one diastereomer is formed and both cyanomethylidene fragments possess exclusively Z-configuration. The tandem sequence includes the formation of 1,3-oxazolidino-1,2-dihydropyridines which undergo Diels–Alder cyclodimerization to give the final products.

2,3-Dihydrofuro[3,2-c]coumarin-3-one was synthesized in quantitative yield from 3-(ω-bromoacetyl)-4-hydroxycoumarin in the presence of nucleophiles (including solvents). This compound undergoes keto-enol tautomerization and easily reacts with aromatic and heteroaromatic aldehydes to form crotonization products having a Z configuration and exhibiting strong fluorescence.

Ethyl 3-(4,5,6,7-tetrahydroindol-2-yl)propynoate, readily available from 4,5,6,7-tetrahydroindole and ethyl bromopropynoate, when treated with dichlorodicyanobenzoquinone (DDQ) in methanol affords furan-2-one–4,5,6,7-tetrahydroindole–cyclobutene sequence in a 52% yield. As kinetic and minor products, a furan-2-one isomer along with bicycloheptadienone have been either isolated or identified. The reaction has been shown to proceed via the isolable intermediate the [2+2]-cycloadduct of ethyl 3-(4,5,6,7-tetrahydroindol-2-yl)propynoate with DDQ. Other alcohols react with the [2+2]-cycloadduct in a similar way. The effect of the alcohol structure on the products ratio has been analyzed. All the intermediates and products are formed as single diastereomer, thus indicating a concerted character of the rearrangement.

New pyridine-phosphine chalcogenide ligands, tris[2-(2-pyridyl)ethyl]phosphine sulfide 1a and tris[2-(2-pyridyl)ethyl]phosphine selenide 1b , react with zinc(II) and cadmium(II) chlorides in EtOH at room temperature to afford complexes of compositions 2ZnCl 2 ·2L ( 2 , L = 1a ) and 3CdCl 2 ·2L ( 3a , b , L = 1a , b ) in high yields. The solid-state structure of complexes 2 , 3 has been proved by X-ray analysis data. Complex 2 is a centrosymmetric dimer, where two atoms of zinc are bonded by two bridging pyridine-phosphine sulfide ligands through N atoms. Complexes 3a , b exist as polymeric chains with each bridging ligand acting as a chelate N,S- or N,Se-donor to one cadmium(II) center and as a pyridine N-donor to the next cadmium(II) center.

Substituted imidazoles (substituents are Me, Et, i-Bu, n-Hexyl, (CH2)2S–Bu-n, Ph, Bn) react smoothly (room temperature, without catalyst and solvent) with cyanoacetylenes (3-phenyl-2-propynenitrile and 4-(1-butoxyethoxy)-4-methyl-2-pentynenitrile) and aromatic or heteroaromatic aldehydes (benzaldehyde, 4-CN-benzaldehyde, pyridine-3-aldehyde) to give 3-(2-imidazolyl)-3-aryl-2-acylpropanenitriles, a hitherto unknown family of functionalized imidazole derivatives, in up to 62% yield. This three-component manifold represents a novel C(2)-functionalization of the imidazole nucleus involving zwitterionic, carbene and enol ether intermediates. Unlike the analogous reaction with aliphatic aldehydes, which gives enol ethers, in this case the latter undergo the further rearrangement to 3-(2-imidazolyl)-3-aryl-2-acylpropanenitriles.

Molecular conductors based on the 8-hydroxy cobalt bis(dicarbollide) anion, (TMTTF)[8-HO-3,3'-Co(1,2-C2B9H10)(1',2'-C2B9H11)] (1), (BMDT-TTF)[8-HO-3,3'-Co(1,2-C2B9H10) (1',2'-C2B9H11)] (2), and (BEDT-TTF)[8-HO-3,3'-Co(1,2-C2B9H10)(1',2'-C2B9H11)] (3), were synthesized, and their crystal structures and electrical conductivities were determined. Compounds 2 and 3 are isostructural to the corresponding radical-cation salts of the parent cobalt bis(dicarbollide). All of the radical-cation salts prepared were found to be semiconductors. The relative stability of the rotation conformers of the [8-HO-3,3'-Co(1,2-C2B9H10)(1',2'-C2B9H11)](-) anion was estimated using DFT/BP86 quantum chemical calculations.

Mechanisms of intramolecular transformations of carbanions generated from 2-aza-1,3,5-trienes by the action of potassium tert-butoxide, which could lead to homo- or heteroannular azacycloheptadienes, were studied by quantum-chemical methods in terms of the density functional theory. The corresponding gradient channels were localized for model 1-methylsulfanyl-1-(cyclopentylideneamino)- and 1-methylsulfanyl-1-(cyclohexylideneamino)buta-1,3-dien-2-ols. Analysis of the kinetic and thermodynamic parameters showed that carbanion generated from N-cyclopentylidenebuta-1,3-dien-1-amine undergoes rearrangement mainly into homoannular azacycloheptadiene and that analogous N-cyclohexylidene derivative gives rise to heteroannular isomer. The results of calculations were consistent with the experimental data.

The [2+2]-cycloadducts of DDQ and 2-ethynylpyrroles, upon ethanolysis (reflux, 15 min or room temperature, 24 h), rearrange from bicyclo[4.2.0]octadienediones to bicyclo[3.2.0]heptadienone- and cyclobutenyl-dihydrofuranone moieties in 55–83% yields, the former rearrangement being the major direction. Benzoquinone ring cleavage is regioselective to afford mostly bicyclo[3.2.0]heptadienone-pyrrole ensembles (85–90% selectivity) in 39–78% yields. The only exception is when the starting compounds contain an ethoxycarbonyl substituent and the pyrrole counterpart is a 4,5,6,7-tetrahydroindole fragment. In this case, the ratio of the rearrangement products is 1:1.2 in a total yield of 83%. An important feature of the dihydrofuranone pathway rearrangement is its 100% diastereoselectivity.

According to 1? and 13? NMR data, enamines of 3-formyl-4-hydroxycoumarin exist in the keto enamine tautomeric form and undergo Z/E-isomerization around the C=C bond in CDCl3, DMSO-d6, and CD3OD at room temperature. The activation energies of ?/Z-isomerization were measured experimentally and calculated by the B3LYP/6-311++G(d,p) method. An X-ray diffraction study showed that 3-(benzyliminomethyl)chromane-2,4-dione in the crystalline state exists as a mixture of two keto enamine isomers.

Methyl substituted 2-phenyldiazenyl-N-vinylpyrroles when refluxed in toluene in the airflow are unexpectedly oxidized at their methyl substituents retaining the pyrrole and N-vinyl moieties intact. The major products of the autooxidation are hydroxyalkyl derivatives (yield up to 60%), the corresponding aldehydes being formed in minor quantities (yield up to 21%). This non- typical oxidation of substituted pyrroles opens a conceptually novel approach to functionalization of phenyldiazenylpyrrole dyes.

The radical cation salts of tetrathiafulvalene (TTF) and bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) with iodo derivatives of cobalt bis(dicarbollide), (TTF)[9,9′,12,12′-I4-3,3′-Co(1,2-C2B9H9)2] and (BEDT-TTF)[9,9′(12′)-I2-3,3′-Co(1,2-C2B9H10)2], respectively, were synthesized and their crystal structures were determined. The introduction of iodine atoms into the lower rim of the dicarbollide ligands, unlike the substitution at the upper rim, leads to insignificant changes in the crystal structure and the conductivity of the radical cation salts compared to the analogous salts based on unsubstituted cobalt bis(dicarbollide).

We performed the synthesis of a (N-Me-3,5-di-Me-Py)(TCNQ)2 single crystal and we resolved the crystallic and molecular structure of this salt. Magnetic susceptibility measurements were performed in the temperature range 2–300 K. The results are studied with respect to two energy gaps in the magnetic excitations spectra which could signify that the Peierls dielectric phase forms in two grades.

Secondary phosphines, elemental selenium, and the natural alkaloids, lupinine and anabasine, interact in a three-component-type reaction under mild conditions (70 °C, 1–1.5 h, EtOH) without the formation of any by-products to give diselenophosphinates of the above-mentioned alkaloids (in almost quantitative yields) with the retention of their intrinsic optical activity. Thus, the developed synthesis represents an atom-economic route to new selenophosphorus derivatives of alkaloids.

Adenine (9H-purin-6-amine) adds readily to available α,β-acetylenic γ-hydroxy nitriles under mild conditions (molar ratio 1:1, K2CO3, DMF, rt, 10 min) to afford chemo-, regio- and stereospecifically (Z)-3-(6-amino-9H-purin-9-yl)-4-hydroxy-4-alkyl-2-alkenenitriles, novel functionalized acyclic nucleoside analogues (95–98% yield). Under similar conditions (K2CO3, DMF, rt, 1 h), 8-azaadenine (3H-[1,2,3]triazolo[4,5-d]pyrimidin-7-amine) reacts with 4-hydroxy-4-methyl-2-pentynenitrile nonselectively at the 7-, 8- and 9-positions to give the corresponding adducts in a 1:10.5:9 ratio, the total yield being 81%. Chemo-, regio- and stereospecific addition of 8-azaadenine to the above α,β-acetylenic γ-hydroxy nitriles leading to (Z)-3-(7-amino-2H-[1,2,3]triazolo[4,5-d]pyrimidin-2-yl)-4-hydroxy-4-alkyl-2-alkenenitriles in 44–90% yield is attained when the reaction is carried out without solvent in the presence of Et3N (30 mol %), the molar ratio of 8-azaadenine:α,β-acetylenic nitriles being 1:2.0 (rt, 12–38 h).

Previously unknown bis[2-(4-tert-butyl)phen]ethylphosphine sulfide is obtained with a high yield from 4-tert-butyl styrene, red phosphorus, and elemental sulfur. Using single crystal XRD, multinuclear NMR, IR, and UV spectroscopy, it is found that the phosphorus atom is four-coordinated in the bis[2-(4-tert-butyl)phen]ethylphosphine sulfide molecule (regardless of the phase state of the compound: crystal, solution). By the example of phosphorylation of bis[2-(4-tert-butyl)phen]ethylphosphine sulfide acetylene in the KOH-DMSO system it is shown that the reaction proceeds by double addition with the participation of phosphorus-centered nucleophiles.

6,7-Dialkynyl-1,3-dimethylpteridine-2,4(1H,3H)-diones and 2,3-dialkynylquinoxalines have been shown to react with sodium azide in DMF at room temperature giving rise 9,11-dimethyl-[1,2,3]triazolo[1′,5′;1,2]pyrido[4,3-g]pteridine-8,10(9H,11H)-diones and [1,2,3]triazolo[1′,5′;1,2]pyrido[3,4-b]quinoxalines. A novel tandem cyclization involves 1,3-dipolar cycloaddition of an azide ion to the carbon–carbon triple bond followed by intramolecular nucleophilic addition of the intermediate 1,2,3-triazole N-anion to another C C bond.

TTF, TTF-BMDT, TTF-BEDT and TMTSF cation radical salts of cobalt bis(dicarbollide) anion [3,3′-Co(1,2-C2B9H11)2]− and its derivatives are prepared and their crystal structures and electrical conductivities are determined. Some regularities in the crystal structures of the TTF-based radical cation salts prepared are also discussed.

An anion-radical salt (ARS) (N-Me-2,5-di-Me-Pz)(TCNQ) 2 , where Pz is pyrazine, was synthesized and its crystal structure was resolved. X-ray diffraction experiments on single crystals were performed. Heat capacity was measured in the temperature range from 2 to 300 K. Magnetisation and magnetic susceptibility were measured in the temperature range from 2 to 300 K and the low-temperature part was measured in magnetic fields from 5 mT to 5 T. The experimental results were explained in terms of dimerized Heisenberg spin 1 2 chain model. Numerical calculations were performed and compared with experimental data.

The one-pot reaction of natural amino acids (glycine, β-alanine, γ-aminobutyric and ɛ-aminocapronic acids, d , l -valine, d , l -leucine, anthranilic acid) with bielectrophilic acylacetylenes proceeds chemo-, regio- and stereospecifically in the presence of NaOH (45–50 °C, 4 h, EtOH–H2O) to give (after treatment of the reaction mixture with aqueous HCl) Z-isomers of N-acylvinyl derivatives of amino acids in 87–94% yield.

A facile, consecutive, self-consisting assembly of two molecules of ketones with two molecules of acetylene to afford 7-methylene-6,8-dioxabicyclo[3.2.1]octanes, which are unknown congeners of widespread insect pheromones, has been discovered. The reaction is realized in a one-pot procedure in a MOH/DMSO system (M = K, Cs) at 80 °C for 1 h under acetylene pressure or under atmospheric pressure; the isolated yields of the bicycles reached 86 %. The new reaction conceptually contributes to the synthesis of insect pheromones as well as to the chemistry of ketones and acetylene. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

2,3-Dihydrofuro[3,2- c]coumarin-3-one reacts with aromatic amines in two pathways, depending on the solvent. The reactions in ethanol afford its enamines, while the use of acetic acid favors the formation of enamines of the 2,3-dihydrofuro[3,2-c]coumarin-3-one dimer. Electronic absorption spectroscopy in different solvents revealed that the enamines obtained can undergo tautomeric transformations. The product of a reaction of 2,3-dihydrofuro-[3,2-c]coumarin-3-one with 4-bromoaniline exists in the enamine form (X-ray diffraction data).

A three-component reaction of secondary phosphine selenides- R 2 P(Se)H [R = PhCH 2 CH 2 ,PhCH(Me)CH 2 , 4- T-BuC 6 H 4 CH 2 CH 2 ,(2-methyl-5-pyridyl)CH 2 CH 2 , Ph],elemental selenium, and primary, secondary, and tertiary aminesand diamines proceeds under mild conditions (25-85 ˚C,1-90 min) in tetrahydrofuran-ethanol as mediumto give previously unknown mono-, di-, and triorganoammonium saltsof diorganodiselenophosphinates in high yields (up to 99%).

A new three-component reaction between alkyl aryl(hetaryl)ketoximes, acetylene, and aliphatic ketones in the superbasic systems KOH/DMSO and LiOH/CsF/DMSO (70–90 °C, initial acetylene pressure 13–15 atm, 5–60 min) affords novel 4-methylene-3-oxa-1-azabicyclo[3.1.0]hexanes in yields of up to 75%. Using KOH/DMSO, the side products of the reaction are O-vinylketoximes and 2-aryl(hetaryl)pyrroles, while with LiOH/CsF/DMSO, the reaction proves to be selective, only minor amounts of the corresponding alkyl aryl(hetaryl) ketones being detectable.

New molecular conductors on the base of 8,8′-diiodo cobalt bis(dicarbollide) anion (TTF)[8,8′-I2-3,3′-Co(1,2-C2B9H10)2] (1), (BMDT-TTF)4[8,8′-I2-3,3′-Co(1,2-C2B9H10)2] (2) and (BEDT-TTF)2[8,8′-I2-3,3′-Co(1,2-C2B9H10)2] (3) were synthesized and their crystal structures and electrical conductivities were determined. All the radical cation salts prepared were found to be semiconductors. Some regularities in the crystal structures of the TTF-based radical cation salts with bis(dicarbollide) complexes of transition metals are discussed.