14007-05-7Relevant articles and documents
Efficient diffusion-controlled ligand exchange crystal growth of isostructural inorganic-organic halogenidorhodates(III): The missing hexaiodidorhodate(iii) anion
Bujak, Maciej
, p. 1295 - 1302 (2015)
The monohydrates of piperazine-1,4-diium hexabromidorhodate(III) bromide and hexaiodidorhodate(III) iodide were obtained by a diffusion-controlled ligand exchange crystal growth method using a hydrochloric acid solution of rhodium(III) chloride trihydrate and piperazine, dissolved in hydrobromic and hydroiodic acid, respectively, separated by a layer of hydrohalic acid. Both inorganic-organic hybrids are defined by the general formula (C4H12N2)2[RhX6]X·H2O (X = Br, 1 or I, 2). They both crystallize in the orthorhombic Pnma space group, and they are isostructural with an isostructurality index above 95%. The cationic building blocks-piperazine-1,4-diium ions and the inorganic components-slightly distorted octahedral [RhX6]3- complexes, isolated X- anions and water of crystallization molecules are connected by related but different systems of interactions. The comparison of packing arrangements and interactions in the crystals of 1 and 2 with those in metal-free (C4H12N2)Br2·H2O, 3, and (C4H12N2)I2·I2, 4, clearly illustrates the occurrence and hierarchy of specific interactions: the bromide-containing structures are dominated by the O/N/C-H···X hydrogen bonds that are less pronounced or exchanged by the X···X halogen bonds in the corresponding iodide-containing structures. The structural features derived from the X-ray diffraction studies are confirmed by the solid-state IR and Raman spectroscopic results supported by the thermoanalytical analyses.
OXAZOLIDINONE ANTIBIOTICS
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Page/Page column 132, (2008/12/08)
The invention relates to compounds of formula (I) wherein U, V, W, X, R1, R2, R3, R4, R5, R6, A, B, D, E, G, m and n are as defined in the description, to pharmaceutically acceptable salts of such compounds for use in the manufacture of a medicament for the prevention or treatment of a bacterial infection. Certain compounds of formula (I) are new and are also part of this invention.
EFFECT OF THE NATURE OF THE LEAVING GROUP IN REACTIONS OF 2-X-N-ETHYLPYRIDINIUM SALTS WITH AMINES IN ACETONITRILE
Titskii, G. D.,Mitchenko, E. S.
, p. 1949 - 1954 (2007/10/02)
The rate-determining stage in the nucleophilic substitution reactions of 2-X-N-ethylpyridinium salts with piperidine in acetonitrile changes, depending on the nature of the leaving group X.In the case where X = Hlg the controlling stage is the formation of the C-N bond.When X = 4-NO2C6H4O3, 3,4-(NO2)2C6H3O, and 2,6-(NO2)2C6H3O, nucleophilic substitution at the carbon atom is controlled by cleavage of the C-X bond.Nucleophilic substitution at a carbon atom of the benzene ring predominates in the reaction of 2-(2,4-dinitrophenoxy)-N-ethylpyridinium salt with piperidine.