Application of N-(ω-bromoalkyl)tetrazoles for the preparation of bitopic ligands containing pyridylazole chelators or azole rings as building blocks for iron(II) spin crossover polymeric materials

1-(3-Bromopropyl)tetrazole, 2-(3-bromopropyl)tetrazole, 1-(4-bromobutyl)tetrazole, and 2-(4-bromobutyl)tetrazole were synthesized with the aim to prepare flexible bitopic ligands contaning 1- or 2-substituted tetrazole ring linked through 1,3-propylene or 1,4-butylene spacer with pyridylazole or azole unit. Twenty-six novel ligands i.e., α-(pyridylazolyl)-ω-(tetrazolyl)alkanes, α-(tetrazolyl)-ω-(1,2,3-triazolyl)alkanes, and α-(tetrazol-1-yl)-ω-(tetrazol-2-yl)alkanes were prepared by an alkylation of sodium salts of 5-(2-pyridyl)tetrazole, 3-(2-pyridyl)-1,2,4-triazole, 3-(2-pyridyl)pyrazole, 1,2,3-triazole, and 1,2,3,4-tetrazole with N-(ω-bromoalkyl)tetrazoles. An alkylation of 5-(2-pyridyl)tetrazole, 1,2,3,4-tetrazole, and 1,2,3-triazole afforded both N1- and N2-regioisomer whereas in the case of 3-(2-pyridyl)-1,2,4-triazole and 3-(2-pyridyl)pyrazole only N1 isomers were isolated. The positions of alkylation were confirmed by X-ray diffraction studies of 1-(5-(2-pyridyl)tetrazol-2-yl)-4-(tetrazol-1-yl)butane, 1-(3-(2-pyridyl)-1,2,4-triazol-1-yl)-4-(tetrazol-2-yl)butane, 1-(3-(2-pyridyl)pyrazol-1-yl)-4-(tetrazol-1-yl)butane, and 1-(tetrazol-1-yl)-4-(1,2,3-triazol-1-yl)butane. Preliminary investigations of magnetic properties of iron(II) complex with 1-(3-(2-pyridyl)-1,2,4-triazol-1-yl)-4-(tetrazol-1-yl)butane revealed that obtained product exhibit thermally induced spin transition accompanied by the thermochromic effect.     

Incorporation of a Phenanthrene Subunit into a Sapphyrin Framework: Synthesis of Expanded Aceneporphyrinoids

32‐Hetero‐5,6‐dimethoxyphenanthrisapphyrins—macrocycles that link structural features of polycylic aromatic hydrocarbons and expanded porphyrins—were obtained in a straightforward [3+1] condensation reaction of dimethoxyphenanthritripyrrane and 2,5‐bis(arylhydroxymethyl)heterocyclopentadienes. The highly folded conformation of formally 4 n π‐electron macrocycles causes them to manifest only limited macrocyclic π conjugation as explored by means of NMR spectroscopic and X‐ray structural analyses, and supported by DFT calculations. Although protonation does not change their π‐conjugation characteristics, the cleavage of ether groups at the phenanthrenylene moiety yields nonaromatic 32‐hetero‐5,6‐dioxophenanthrisapphyrins.     

Preparation and Crystal Structure of Rare Earth Rhenates: the Series Ln5Re2O12 with Ln = Y,Gd–Lu,and the Praseodymium Rhenates Pr3ReO8, Pr3Re2O10, and Pr4Re2O11

The crystal structure of the known compounds Ln₅Re₂O₁₂ (Ln = Y, Gd, Dy–Lu) and the new isotypic terbium rhenate Tb₅Re₂O₁₂ was determined from X‐ray data of a twinned crystal of Ho₅Re₂O₁₂: B2/m, a = 1236.5(4) pm, b = 748.2(2) pm, c = 563.8(1) pm, γ = 107.73(3)°, Z = 2, R = 0.034 for 379 structure factors and 37 variable parameters. The rhenium atoms (oxidation number +4.5) have octahedral oxygen coordination. These ReO₆ octahedra share edges, thus forming infinite strings with alternating short and long Re–Re distances: 243.6(2) and 320.1(2) pm. Of the three holmium positions two are surrounded by seven oxygen atoms and the third one has octahedral oxygen coordination. The crystal structure of Pr₃ReO₈ was refined from single‐crystal X‐ray data: P2₁/a, a = 1498.0(2) pm, b = 749.09(8) pm, c = 610.48(9) pm, γ = 110.39(1)°, R = 0.017 for 2082 F values and 110 variable parameters. It is isotypic with a structure first determined for Sm₃ReO₈. The new compounds Pr₃Re₂O₁₀ and Pr₄Re₂O₁₁ were prepared by reaction of elemental praseodymium with the metaperrhenate Pr(ReO₄)₃. They were characterized through their X‐ray powder diagrams. Pr₃Re₂O₁₀ was found to be monoclinic: a = 778.47(9) pm, b = 773.62(9) pm, c = 706.10(8) pm, β = 114.77(1)°. It is isotypic with La₃Os₂O₁₀ and La₃Re₂O₁₀. Pr₄Re₂O₁₁ crystallizes with Nd₄Re₂O₁₁ type structure with the tetragonal lattice constants a = 1272.49(3) pm, c = 562.29(2) pm. The compounds Nd₄Re₂O₁₁ and Sm₄Re₂O₁₁ are confirmed. The magnetic properties of Ho₅Re₂O₁₂, Tb₅Re₂O₁₂, Pr₃Re₂O₁₀, Pr₄Re₂O₁₁, Nd₄Re₂O₁₁, and Sm₄Re₂O₁₁ were investigated with a Faraday balance. None of these compounds shows magnetic order above 200 K.     

Progressive Frictional Delamination of an Infinite Elastic Film on a Rigid Substrate Due to In-Plane Point Loading

The paper presents a solution to a delamination problem of an infinite elastic film resting on a rigid substrate and loaded by a monotonically increasing in-plane point force. A?rigid-slip contact is assumed between the film and the substrate, leading to the development of two regions at the interface: a damaged zone with a relative slip between the materials, and a region where the interface remains intact. Both film natural and essential boundary conditions are zero on the boundary between these two interfacial zones with the shape of the boundary being a part of the solution. Problem??s self-similarity enables us to obtain an approximate distribution of interfacial traction within the delaminated zone and a shape of the zone itself. For film??s Poisson??s ratio ??=?1 the approximate solution becomes exact. It is argued that this can be treated as a special case of a rigid film sliding on a rigid substrate. The presented approach can be used to obtain approximate closed-form solutions to similar delamination problems.     

Shaping a Porphyrinoid Frame by Heteroatoms Extrusion: Formation of an Expanded [22]Triphyrin(6.6.0)

An aromatic expanded triphyrin, [22]triphyrin(6.6.0) 2 , containing a pyrrole unit, a bipyrrole moiety, and annulene links, was obtained from a tellurium-containing precursor meso-tetraaryl-26,28-ditellurasapphyrin 1 . The reaction path proceeds through an acid-promoted tellurium extrusion from 1 yielding directly 2 , characterized in a dicationic form by X-ray crystallography. In solution the neutral macrocycle 2 reveals flexibility typical for annulenes and it exists as a mixture of conformers that differ by the configuration of the annulene fragments, as proven by ¹H NMR studies and analyzed by DFT methods. The conformation is controlled by protonation state, the nature of an interacting anion, solvent identity, and by interaction with water.     

Collective characteristics of hadron systems produced in beam fragmentation of π+ p collisions at 250 GeV/c

Collective characteristics are studied of hadrons produced in beam fragmentation of non-single-diffractive π⁺ p-interactions at 250 GeV/c. An attempt is made to obtain experimental information on the properties of leading cluster production and fragmentation. On average, the leading cluster carries 0.8±0.1 of the incident momentum, so that the mean value of the inelasticity coefficient of 〈k〉=0.2±0.1 is significantly smaller than that deduced from leading single hadron spectra. The momentum transfer distribution shows that nonsingle-diffractive processes are less peripheral than diffraction dissociation. The analysis of thrust and sphericity shows jet-like structure of pion fragmentation, that of the charge flow an average forward charge of 〈Q _f 〉=0.45±0.04, in agreement with the average charge of the beam valence quarks. Our data are compared to diffraction dissociation and to the Fritiof model.     

Open subsets of projective spaces with a good quotient by an action of a reductive group

The aim of the paper is to describe all open subsets of a projective space with an action of a reductive group which admits a good quotient. As in the case of Mumford’s geometric invariant theory (which concerns projective good quotients) the problem can be reduced to the case of an action of a torus. We also show how to distinguish examples of open subsets with a good quotient coming from Mumford’s theory and give examples of open subsets with non-quasi-projective quotients.     

系列新IFS分形图象的获取与分析

首次发现了类似墨竹叶之ＩＦＳ分形图及其系列衍生图象的生成     

Synthesis of 5,7,11 b,12-tetrahydro-isoindolo[2,1-b]isoquinolinium methiodides and theirStevens rearrangement

The title compounds5 were synthetized in two steps from the corresponding isoindolo[2,1–b]isoquinoline-5(7H)-ones3, obtained in high yields from 3-ethoxy-1H-isoindoles2 and homopthalic anhydrides1. TheStevens rearrangement of5 gave 2-methyl-2,3-dihydro-1H-isoindole-1-spiro-2-indanes6.

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Synthese von 5,7,11 b,12-Tetrahydro-isoindolo[2,1-b]isochinolinium Methiodiden und ihre Stevens-Umlagerung

Zusammenfassung Die Titelverbindungen5 wurden in zwei Stufen aus den entsprechenden Isoindolo[2,1–b]isochinolin-5(7H)-onen (3) dargestellt, die ihrerseits in hohen Ausbeuten aus 3-Ethoxy-1H-isoindolen (2) und Homophthalsäureanhydriden erhältlich sind. DieStevens-Umlagerung von5 führte zu 2-Methyl-2,3-dihydro-1H-isoindol-1-spiro-2-indanen (6).