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Inorg Chem ; 58(2): 1048-1057, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30601648


The unique L2Cu6I6 complexes containing two Cu3I3 units have been obtained via reaction of 1,5-diaza-3,7-diphosphacyclooctanes bearing ethylpyridyl substituents at phosphorus atoms with an excess of copper iodide. The structure of one of the complexes was confirmed by X-ray diffraction. It was shown that the complexes can exist in two crystalline phases with different parameters of the unit cell, which were detected by the PXRD data analyses. The solvent-free crystalline phases of the complexes display rare solid-state white emission at room temperature, which is observed due to the presence of two broad bands in the emission spectra with maxima at 464 and 610 nm. Quantum chemical computations show that the high-energy band has 3(M+X)LCT origin, whereas the low-energy band is interpreted as 3CC. The quantum yields of white luminescence of complexes reach 15-20%.

Dalton Trans ; 43(33): 12784-9, 2014 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-25017488


Novel 18- and 20-membered P,N-macrocycles have been obtained stereoselectively by covalent self-assembly of α,ω-bisphosphines, formaldehyde and benzylamine. Alternating SSSS/RRRR or RSSR diastereomers were formed in the row of the 14-, 16-, 18- and 20-membered macrocyclic aminomethylphosphines. For the first time it was demonstrated that the stereochemical result of the reaction depends on the even or odd number of the methylene groups between the two chiral phosphorus atoms in the initial α,ω-bisphosphines.

Chemistry ; 20(11): 3169-82, 2014 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-24523072


Eight-membered cyclic functional bisphosphines, namely 1,5-di-aryl-3,7-di(2-pyridyl)-1,5-diaza-3,7-diphosphacyclooctanes (aryl=2-pyridyl, m-tolyl, p-tolyl, diphenylmethyl, benzyl, (R)-(+)-(α-methyl)benzyl), with 2-pyridyl substituents on the phosphorus atoms have been synthesized by condensation of 2-pyridylphosphine, formaldehyde, and the corresponding primary amine. The structures of some of these bisphosphines have been investigated by X-ray crystallography. The bisphosphines readily form neutral P,P-chelate complexes [(κ(2)-P,P-L)MCl2], cationic bis-P,P-chelate complexes [(κ(2)-P,P-L)2 M](2+), or a five-coordinate complex [(κ(2)-P,P-L)2 NiBr]Br. The electrochemical behavior of two of the nickel complexes, and their catalytic activities in electrochemical hydrogen evolution and hydrogen oxidation, including the fuel-cell test, have been studied.

Org Biomol Chem ; 5(6): 976-81, 2007 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-17340014


Two nitroxide methanofullerenes was synthesized for the first time, and their structures and biological activities studied. It was shown by X-ray single crystal analysis that the methanofullerene with two nitroxide groups forms a 1 : 2 inclusion complex with chloroform and has a nearly tetrahedral (diamond-like) arrangement of fullerene-fullerene interactions in the crystal. For the first time, it has been found that malonate nitroxide methanofullerene in combination with the known anticancer drug cyclophosphamide (CPA) shows high antitumor activity against leukemia P-388.

Fulerenos/química , Fulerenos/farmacologia , Animais , Cromatografia Líquida de Alta Pressão , Cristalografia por Raios X , Ciclofosfamida/uso terapêutico , Espectroscopia de Ressonância de Spin Eletrônica , Fulerenos/uso terapêutico , Leucemia/tratamento farmacológico , Masculino , Camundongos , Modelos Moleculares , Ensaios Antitumorais Modelo de Xenoenxerto
Dalton Trans ; (3): 442-7, 2004 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-15252552


Novel macroheterocyclic tetraphosphines, namely, 1,1',5,5'-bis(arylene)-bis(1,5-diaza-3,7-diphosphacyclooctanes) 2-6, were obtained without the use of high-dilution techniques or any matrix by the reaction of bis(hydroxymethyl)organylphosphines with primary aromatic diamines containing two p-phenylene fragments linked by various one-atom bridges in a molecular self-assembly process. The structures of 4, 5 and 6 were investigated by X-ray crystal structure analyses. The macrocyclic cavities can be described as a truncated rhombohedral prism with side faces formed by phenylene rings and 1,5-diaza-3,7-diphosphacyclooctanes in the truncated acute angles. In the crystals of these macrocycles, solvating DMF molecules are present, and a methyl group from each of two DMF molecules penetrates the macrocyclic cavities of 4 and 5 from either side, whereas only one disordered molecule of DMF penetrates the cavity of macrocycle 6. Different types of crystal packing are observed for the P-benzyl-substituted compounds 4 and 5 and for the P-mesityl-substituted compound 6: for 4 and 5 the formation of alternating layers containing the macrocycles and the DMF molecules is observed, in which the cavities of the macrocyclic molecules form channels and the DMF molecules are located in the centers of the channels; in the crystal of 6, six molecules are arranged around the 3 axis in the fashion of a six-bladed propeller.

Compostos Macrocíclicos/síntese química , Fosfinas/síntese química , Cristalografia por Raios X , Interações Hidrofóbicas e Hidrofílicas , Compostos Macrocíclicos/química , Modelos Moleculares , Estrutura Molecular , Fosfinas/química , Porosidade