Chiroptical properties and new derivatives of cyclopalladated 6-ferrocenyl-2,2′-bipyridine. Molecular structure of a tert-butyl isocyanide derivative

Optically active cyclopalladated 6-ferrocenyl-2,2′-bipyridine has been studied by circular dichroism and luminescent spectroscopy; a replacement of the chloride ion at palladium with the rhodanide ion and tert-butyl isocyanide molecule has been carried out; molecular structure of the product in the latter case has been determined by X-ray diffraction analysis.     

Photoinduced template synthesis of cyclobutane-containing crown ether

The photoinitiated [2+2]-cycloaddition of 1,5-bis[2-(3-phenyl-3-oxoprop-1-en-1-yl)phenoxy]-3-oxapentane in solution was studied. In the presence of potassium cations, the reaction is intramolecular and gives crown ether containing the γ-truxin-type cyclobutane fragment (anti, head-to-head) as the major product. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 204–206, January, 2008.     

One-pot synthesis of 6H-pyrrolo[2,3-e[1,2,4]triazolo[1,5-a]pyrimidines on the basis of σH-adducts of 6-Nitro[1,2,4]triazolo[1,5-a]pyrimidine with carbonyl compounds

Aromatic, heteroaromatic, and aliphatic carbonyl compounds reacted with 6-nitro[1,2,4]triazolo[1,5-a]pyrimidine in the presence of a base to give stable σ^H-adducts at C⁷. Reduction of the nitro group in the latter is accompanied by tandem autoaromatization of the azine ring and intramolecular cyclocondensation with formation of the corresponding 6H-pyrrolo[2,3-e][1,2,4]triazolo[1,5-a]pyrimidines. Original Russian Text ? E.B. Gorbunov, G.L. Rusinov, R.I. Ishmetova, V.N. Charushin, O.N. Chupakhin, 2008, published in Zhurnal Organicheskoi Khimii, 2008, Vol. 44, No. 1, pp. 130–134. Dedicated to Full Member of the Russian Academy of Sciences G.A. Tolstikov on his 75th anniversary     

Specific features of the electronic,spin, and atomic structures of a topological insulator Bi<Subscript>2</Subscript>Te<Subscript>2.4</Subscript>Se<Subscript>0.6</Subscript>

The specific features of the electronic and spin structures of a triple topological insulator Bi₂Te_2.4Se_0.6, which is characterized by high-efficiency thermoelectric properties, have been studied with the use of angular- and spin-resolved photoelectron spectroscopy and compared with theoretical calculations in the framework of the density functional theory. It has been shown that the Fermi level for Bi₂Te_2.4Se_0.6 falls outside the band gap and traverses the topological surface state (the Dirac cone). Theoretical calculations of the electronic structure of the surface have demonstrated that the character of distribution of Se atoms on the Te–Se sublattice practically does not influence the dispersion of the surface topological electronic state. The spin structure of this state is characterized by helical spin polarization. Analysis of the Bi₂Te_2.4Se_0.6 surface by scanning tunnel microscopy has revealed atomic smoothness of the surface of a sample cleaved in an ultrahigh vacuum, with a lattice constant of ~4.23 Å. Stability of the Dirac cone of the Bi₂Te_2.4Se_0.6 compound to deposition of a Pt monolayer on the surface is shown.     

Solvent-free reaction of 3-aryl-6-(3-nitrophenyl)-1,2,4-triazines with 4-(cyclohex-1-en-1-yl)morpholine

The aza-Diels–Alder reaction of 3-aryl-6-(3-nitrophenyl)-1,2,4-triazines with 4-(cyclohex-1-en-1-yl)morpholine as dienophile was accompanied by reduction of the nitro group to amino. In the reaction of 3-(4-methoxyphenyl)-6-(3-nitrophenyl)-1,2,4-triazine with 4-(cyclohex-1-en-1-yl)morpholine, 3-[3-(4-methoxyphenyl)-1,2,4-triazin-6-yl)aniline was formed together with the cycloaddition product.     

Pyrene-1-carboxylic acid polyethylene glycol esters: synthesis and photophysical studies

Russian Chemical Bulletin - Monoesters of tri- and tetraglycol and 1-pyrenecarboxylic acid were characterized for the first time by NMR spectroscopy and elemental analysis. The photophysical...     

Synthesis and antifungal activity of 3-substituted imidazo[1,2-<Emphasis Type="Italic">b</Emphasis>][1,2,4,5]tetrazines

A number of new 3-substituted imidazo[1,2-b][1,2,4,5]tetrazines containing azolyl, aminopyridyl, and alkoxyl substituents was synthesized. These compounds were studied for the biological activity against mycelial anthropophilic and zoophilous dermatophyte fungi (Trichophyton, Microsporum and Epidermophyton), causing diseases of skin and its appendages (hair, nails), and yeast-like fungi Candida.     

Structural analogs of adenosine receptor inhibitors in the series of 1,2,4-triazolo[1,5-<Emphasis Type="Italic">a</Emphasis>]pyrimidines

A universal method was developed for the synthesis of 7-alkylamino-6-nitro-1,2,4-triazolo-[1,5-a]pyrimidines by the chlorodeoxygenation of the corresponding triazolopyrimidones.     

Reactions of pyrazinium salts with phenols:from σ<Superscript>H</Superscript>-adducts to S<Subscript>N</Subscript><Superscript>H</Superscript>products and transformations into benzo[<Emphasis Type="Italic">b</Emphasis>]furans

The reaction of 5-(het)aryl-2,3-dicyano-1-ethylpyrazinium salts with phenol derivatives affords relatively stable dihydropyrazines, whereas the reactions of 6-(het)aryl-1,2,5-oxadiazolo[3,4-b]pyrazin-4-ium protic salts, depending on the phenol structure, result in products of nucleophilic substitution of hydrogen or open-chain transformation products: benzo[b]furan-substituted derivatives. The crystallographic data on the spatial structure of all types of the synthesized products were obtained.     

Chichibabin-type condensation of cyclic ketones with 3-R-1,2,4-triazin-5(4H)-ones

Reactions between substituted 1,2,4-triazines and ketones were investigated. General procedures for one-pot synthesis of hydrogenated derivatives of such polycyclic systems as benzo[c][1,2,4]triazino[1,6-a][2]azecine, [1,2,4]triazino[1,6-f]phenantridine, and dicyclopenta[b,d]pyrido[1,2-f][1,2,4]triazine are described.