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1

Transformacje strukturalne w kryształach wywołane reakcjami fotochemicznymi

Turowska-Tyrk I., Bąkowicz J.

Wiadomości Chemiczne

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2014

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[Z] 68, 5-6

381--402

EN

Structural changes induced in crystals by photochemical reactions were presented. The changes concern: a) the distances between neighbouring reactant molecules and their mutual orientation in the case of intermolecular reactions, b) the distances and angles between fragments of a molecule for intramolecular reactions, c) the position of molecules in crystals, d) geometry of hydrogen bonds, e) cell constants, and f) the content of product molecules in crystals. For most intramolecular reactions, the distances between reactive atoms are constant for a long time in phototransformation and decrease rapidly at its end (Figs. 3 and 5). In the case of intermolecular reactions, the distances between reactive atoms of reactant molecules decrease linearly along with the phototransformation of crystals (Fig. 7). Additionally, unreacted molecules become, to a certain degree, similar to product molecules in terms of their shape (Figs, 4 and 8). Reactant and product molecules do not assume a fixed place in crystals. Product molecules change their orientation towards that of which is observed in a pure product crystal and reactant molecules gradually move away from the position they took in pure reactant crystals. All this has an influence on the geometry of hydrogen bonds existing in crystals (Fig. 9). The above-mentioned structural transformations find their expression in values of cell constants (Fig. 10). The factors influencing the photoreactivity of molecules in crystals were also described. Knowledge of crystal and molecular structures of partly reacted crystals, determined thanks to X-ray structure analysis which is a branch of crystallography, reveals the behaviour of molecules in crystals in which photochemical reactions proceed and helps to understand a pathway of these reactions.

2

Synthesis and Structure of Mono- and Disubstituted Derivatives of 4,5-Dihydro-1H-1,2,4-triazol-5-one

Pitucha M., Dobosz M., Stępniak K., Dybała I., Kozioł A. E.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 12

2103-2114

EN

In the reaction of hydrazide of 1,2,4-triazol-1-acetic acid with isocyanates the semicarbazide derivatives were obtained (Ia-Ii). Depending on the chemical nature of the starting isocyanate, cyclization of Ia-Ii in alkaline medium led to formation of three groups of derivatives of 4,5-dihydro-1H-1,2,4-triazol-5-one (IIa-IIi). Alkyl and aryl substituents of semicarbazides formed 3,4-disubstituted compounds (IIa-IIf), the ethoxycarbonyl group promoted formation of 3-substituted compound IIg, while compounds IIh and IIi are 4-substituted triazol-5-ones resulting from benzoyl and benzenesulfonyl isocyanates. Molecular structures of three products (IIb, IIc, IId) were confirmed by the X-ray structure analysis. Different substituents at the N4 atom (ethyl in IIb, cyclohexyl in IIc and 1-naphthyl in IId) influence the molecular association pattern in the crystal structure.

3

Monitoring Structural Transformations in Crystals. Part 10. Monitoring Molecular and Crystal Structures During a Yang Photocyclization Reaction – Comparative Studies

Turowska-Tyrk I., Łabęcka I., Scheffer J., Xia W.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 5-6

813-824

EN

Structural changes in a crystal, brought about by the Yang photocyclization of the 2-(4-carboxybenzoyl)-2-methyl-endo-bicyclo[2.1.1]hexyl salt with (S)-(–)--phenylethylamine, were monitored by means of X-ray structure analysis. The changes taking place in the reaction centre, as well as changes inmolecular orientation and cell constants are discussed. Analysis of the geometrical parameters describing the reaction centre enabled an evaluation of the possibility of formation of the opposite enantiomer in a crystal. The results are compared with data for other intramolecular photochemical reactions.

4

Synthesis of New Derivatives of 1,2,4-Triazol-3-one

Struga M., Dobosz M., Kossakowski J., Dybała I., Stępniak K., Kozioł A.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 6

889-897

EN

Reactions of nucleophilic substitution on 2,5-diphenyl-, 1,5-diphenyl-, and 5-phenyl-1,2,4-triazol-3-one were studied. Both O- and N-derivatives were obtained. Molecular structure proposed for this group of compounds was confirmed by X-ray structure analysis of selected crystals (4a, 2b, 4b, 5c).

5

Investigation of the Tm2Se3–Cu2Se–PbSe and Lu2Se3–Cu2Se–PbSe Systems at 870 K

Gulay L., Wołcyrz M., Pietraszko A., Olekseyuk I.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 10

1703-1714

EN

Phase equilibria in Tm2Se3–Cu2Se–PbSe and Lu2Se3–Cu2Se–PbSe systems at 870 K were investigated, using X-ray powder diffraction. R(2+x)/3Cu2-xSe2 (0 x 1) solid solutions (space group P3) were found in R2Se3–Cu2Se (R = Tmand Lu) sections of both systems. Crystal structure determinations for terminal RCuSe2 compositions of these solid solutions were performed. Er2/3Cu2S2 structure type was confirmed for TmCuSe2. LuCuSe2 crystallizes in the same structure, but with one extra position for Lu atoms. Crystal structures of R2PbSe4 (space group Pnma) in R2Se3–PbSe sections were determined usingX-single crystal and powder diffraction forR =Tmand Lu, respectively. The existence of R3.33CuPb1.5Se7 (Lu3.33CuPb1.5Se7 structure type, space group Cm), RCuPbSe3 (-BaLaCuSe3 structure type, space group Pnma) and Tm5CuPb3Se11 (Er5CuPb3Se11 structure type, space group Cmcm) compounds in R2Se3–Cu2Se-PbSe (R = Tm and Lu) systems was confirmed.

6

Investigation of the Tb2Se3-Cu2Se-PbSe and Dy2Se3-Cu2Se-PbSe Systems at 870 K

Gulay L., Wolcyrz M., Olekseyuk I.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 5

805-815

EN

Isothermal sections of the Tb2Se3-Cu2Se-PbSe and Dy2Se3-Cu2Se-PbSe systems at 870 K were explored using X-ray powder diffraction. TbCuSe2 compound (LaCuS2 structure type, space group P21/c) and Tb(2+x)/3Cu2-xSe2 (0 _ x _ 0.85) solid solution (Er2/3Cu2S2 structure type, space group P3) were identified in the Tb2Se3-Cu2Se section and their crystal structures were determined. The existence of Dy(2+x)/3Cu2-xSe2 (0 _ x _1) solid solution (Er2/3Cu2S2 structure type, space group P3) was confirmed in the Dy2Se3-Cu2Se section and its structure was refined. Tb2+2xPb1-3xSe4 (0.07 _ x _ 0.19) solid solution (Th3P4 structure type, space group I43d) was identified and Dy6Pb2Se11 compound (Y6Pb2Se11 structure type, space group Cmcm) was observed in the R2Se3-PbSe section of the system with R = Tb or Dy, respectively. Crystal structure of Tb2+2xPb1-3xSe4 was refined. The existence of Tb3.33CuPb1.5Se7 (Lu3.33CuPb1.5Se7 structure type, space group Cm) and TbCuPbSe3 (beta-BaLaCuSe3 structure type, space groupPnma) compounds in the Tb2Se3-Cu2Se-PbSe system as well as of the isostructural Dy3.33CuPb1.5Se7 and DyCuPbSe3 compounds in the Dy2Se3-Cu2Se-PbSe system was confirmed

7

Monomeric molecules in the isostructural calcium(II) and strontium(II) complexes with pyrazine-2-carboxylic acid

Ptasiewicz-Bąk H., Ostrowski A., Leciejewicz J.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 8

2014-2023

EN

The crystals of cis-tetraquobis(pyrazine-2-carboxylato-O,N)calcium(II) contain monomeric molecules, in which the calcium ion has a distorted dodecahedral coordination, formed by four water molecules (mean Ca-O = 2.441 A), two oxygen atoms from monodentate carboxylic groups of two pyrazinic acid molecules (mean Ca-O = 2.458 A) and two nitrogen atoms located next to the above carboxylic groups (mean Ca-N = 2.619 A). In the crystals of cis-tetraquobis(pyrazine-2-carboxylato-O,N)strontium(II) the coordination of the Sr(2+) ion is identical with that of the calcium complex, the corresponding mean distances being Sr-O(water) 2.572 A, Sr-O 2.588 A, Sr-N 2.751 A. The monomeric molecules of both compounds are linked via a network of hydrogen bonds.