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Od rozpoznania molekularnego do rozdziału racemicznego metodą frakcyjnej krystalizacji soli diastereomerycznych

Białońska A.

Wiadomości Chemiczne

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2014

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[Z] 68, 5-6

545--562

EN

Synthesis and isolation of enantiopure compounds remains an important challenge in medicinal, pharmaceutical, alimentary as well as material chemistry. Amongst many methods leading to enantiopure compounds, formation and fractional crystallization of diastereomeric salts of an enantiopure resolving agent is the most popular one. Since its discovery many years went by, and yet it has been performed by the trial and error method. Selection of the suitable resolving agent is crucial for racemic resolution efficiency. Hence, this review is concerned with common features of crystal structures of salts, in which resolving agents, frequently used for separation of racemic acids, are involved. Among them, there are crystal structures of salts of primary, secondary and tertiary chiral amines (1-arylethylamines, ephedrine, pseudoephedrine, deoxyephedrine, chinine, chinidine, cinchonine, cinchonidine, strychnine and brucine). In most of them, cations and anions are involved in characteristic systems of hydrogen bonds leading to formation of cationic-anionic self-assemblies. In this respect, brucine and strychnine appear as unique, because presence of anions usually does not affect formation of common cationic self-assemblies stabilized by weak hydrophobic interactions. Comparison of the common structural motifs indicates different factors being crucial in molecular recognition and in diastereomeric diversification. Formation of common hydrogen bonded cationic-anionic self-assemblies plays a dominant role in molecular recognition of a given acid by most of the studied amines. In turn, formation of common cationic self-assemblies stabilized by hydrophobic interaction plays a crucial role in molecular recognition of a given acid by brucine or strychnine. Diastereomeric diversification can be realized in various ways. In extreme cases, when molecular recognition in crystals of particular diastereomeric salts is similar, diastereomeric diversification is governed by different factors, depending on factors governing molecular recognition. Hydrophobic interactions play an important role in diastereomeric diversification when molecular recognition is governed by hydrogen bonds. In turn, when molecular recognition is governed by hydrophobic interactions, different hydrogen bond systems in crystals of particular salts are responsible for their diastereomeric deversification.

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Laktony. Cz. 40, Synteza i aktywność antyfidantna ε-laktonów skondensowanych z pierścieniem metoksypodstawionego benzenu

Masłowiec D., Nawrot J., Białońska A., Wawrzeńczyk C.

Przemysł Chemiczny

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2012

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T. 91, nr 5

883-889

EN

Benzoxepan-2-one and its 6 methoxy and dimethoxy derivatives where obtained in the reaction of Baeyer-Villiger oxidation of 1-tetralone and its methoxy and dimethoxy derivatives with m-chloroperbenzoic acid. Thre ε-lactones were affected further electophilic hydroxylation to the resp. hydroxy lactones. The starting ketones and lactones were tested for antifeedant activity against insect storage pests: adults of the grain weevil, larvae of the khapra beetle as well as adults and larvae of the confused flour beetle.

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Crystal structure and spectroscopic properties of [Zn(2-qmpe)Cl2] containing diethyl (quinolin-2-ylmethyl)phosphonate ligand (2-qmpe)

Żurowska B., Białońska A., Kotyński A., Ochocki J.

Materials Science Poland

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2010

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Vol. 28, No. 2

573--581

EN

The crystal structure of [Zn(2-qmpe)Cl2] (2-qmpe, diethyl (quinolin-2-ylmethyl) phosphonate) ligand) was determined by X-ray-diffraction. The compound was also characterized by IR, far-IR, 1H and 31P NMR spectroscopy. In the molecule, 2-qmpe acts as a bidentate N,O-chelate ligand. Tetrahedral ZnNOCl2 environment of Zn(II) atom is slightly distorted. The structure is stabilized by intermolecular H bond and n---n interactions. The spectral features are in agreement with the structural data.

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Structure and characterization of copper(II) perchlorate with diethyl(pyridin-2-ylmethyl) phosphonate (2-pmpe) ligand: [Cu(2-pmpe)2(ClO4)2]

Żurowska B., Białońska A., Ochocki J.

Materials Science Poland

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2009

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Vol. 27, No. 4/1

987--998

EN

Copper(II) mononuclear compound [Cu(2-pmpe)2(ClO4)2] (2-pmpe = diethyl(pyridin-2-ylmethyl) phosphonate was synthesized and studied. Examination of the crystal structure by the X-ray diffraction method revealed two crystallographically unrelated molecules, [Cu(1)(2-pmpe)2(ClO4)2] (1) and [Cu(2)(2-pmpe)2(ClO4)2] (2) in an asymmetric part of the unit cell. The geometry about the Cu(1) and Cu(2) chromophores shows elongated octahedra, resulting from the didentate N,O-bonded two chelate 2-pmpe ligands and two coordinated perchlorate ions around the Cu(II) cations (CuN2O4 chromophore). Similarly to 1, molecules 2 are linked to each other by weak C-HoooO hydrogen bonds and ?ooo? stacking interactions. Additionally, both 1 and 2 molecules are linked to each other through weak C-HoooO hydrogen bonds and C-Hooo? contacts, resulting in a 3D polymeric network arrangement. Magnetic data indicate a very weak intermolecular exchange interaction between copper(II) ions (zJ´ = -0.20 cm-1) transmitted through non-covalent interactions in the crystal lattice. The spectral properties are in accordance with the structural and magnetic data.

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Lactones 17. Synthesis of Bicyclic Lactones with the Methyl- or gem-Dimethylcyclopropane System

Obara R., Szumny A., Żołnierczyk A., Olejniczak T., Białońska A., Ciunik Z., Wawrzeńczyk C.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 6

981-993

EN

A new method of synthesis of bicyclic gamma-lactones with the methyl- or gem-dimethylcyclopropane system from gamma,delta unsaturated esters is described. The reaction of gamma-halo delta- lactones with DBU is the key step of this synthesis. The mechanism of the dehydrohalogenation- cyclization process of gamma-halo-delta-lactones is proposed. The structures of products were confirmed by both spectroscopic and crystallographic methods.