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171.
172.
Dr. Maximilian N. Kopylovich Dr. Archana Mizar Dr. M. Fátima C. Guedes da Silva Dr. Tatiana C. O. Mac Leod Dr. Kamran T. Mahmudov Prof. Armando J. L. Pombeiro 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(2):588-600
A one‐pot template condensation of 2‐(2‐(dicyanomethylene)hydrazinyl)benzenesulfonic acid (H2L1, 1 ) or 2‐(2‐(dicyanomethylene)hydrazinyl)benzoic acid (H2L2, 2 ) with methanol (a), ethylenediamine (b), ethanol (c) or water (d) on copper(II), led to a variety of metal complexes, that is, mononuclear [Cu(H2O)2(κO1,κN2 L1a] ( 3 ) and [Cu(H2O)(κO1,κN3 L1b)] ( 4 ), tetranuclear [Cu4(1 κO1,κN2:2 κO1 L2a)3‐(1 κO1, κN2:2 κO2 L2a)] ( 5 ), [Cu2(H2O)(1 κO1, κN2:2 κO1 L2c)‐(1 κO1,1 κN2:2 κO1,2 κN1‐ L2c)]2 ( 6 ) and [Cu2(H2O)2(κO1,κN2‐ L1dd)‐(1 κO1,κN2:2 κO1 L1dd)(μ‐H2O)]2 ? 2 H2O ( 7? 2 H2O), as well as polymer‐ ic [Cu(H2O)(κO1,1 κN2:2 κN1 L1c)]n ( 8 ) and [Cu(NH2C2H5)(κO1,1 κN2:2 κN1L2a)]n ( 9 ). The ligands 2‐SO3H‐C6H4‐(NH)N?C{(CN)[C(NH2)‐(?NCH2CH2NH2)]} (H2L1b, 10 ), 2‐CO2H‐C6H4‐(NH)N?{C(CN)[C(OCH3)‐(?NH)]} (H2L2a, 11 ) and 2‐SO3H‐C6H4‐(NH)N?C{C(?O)‐(NH2)}2 (H2L1dd, 12 ) were easily liberated upon respective treatment of 4 , 5 and 7 with HCl, whereas the formation of cyclic zwitterionic amidine 2‐(SO3?)? C6H4? N?NC(? C?(NH+)CH2CH2NH)(?CNHCH2CH2NH) ( 13 ) was observed when 1 was treated with ethylenediamine. The hydrogen bond‐induced E/Z isomerization of the (HL1d)? ligand occurs upon conversion of [{Na(H2O)2(μ‐H2O)2}(HL1d)]n ( 14 ) to [Cu(H2O)6][HL1d]2 ? 2 H2O ( 15 ) and [{CuNa(H2O)‐(κN1,1 κO2:2 κO1 L1d)2}K0.5(μ‐O)2]n ? H2O ( 16 ). The synthesized complexes 3 – 9 are catalyst precursors for both the selective oxidation of primary and secondary alcohols (to the corresponding carbonyl compounds) and the following diastereoselective nitroaldol (Henry) reaction, with typical yields of 80–99 %. 相似文献
173.
Pirsaheb Meghdad Mohammadi Somayeh Khodarahmi Reza Hoseinkhani Zohreh Mansouri Kamran Payandeh Mehrdad 《Journal of fluorescence》2022,32(5):1733-1741
Journal of Fluorescence - In this research, DNA-modified carbon dots (CDs) were exploited to construct a fluorescence assay for breast cancer genes (BRCA1, a potential marker for cancer diagnosis)... 相似文献
174.
Kamran AkhbariAli Morsali 《Polyhedron》2011,30(15):2459-2465
A new thallium(I) supramolecular polymer, [Tl4(μ3-4-BN)4]n (1) [9-HBN = 4-hydroxy benzonitrile], with a disordered cubic cage structural unit has been synthesized and characterized. The single-crystal X-ray data of compound 1 shows one type of TlI ion in the tetranuclear cubic cage structure with a coordination number of three. In addition to two intra cage thallophilic interactions in 1, each thallium(I) atom has a weak Tl?N secondary interaction with the nitrile group of the 4-BN− ligand. Finally the Tl-ions attain the O3Tl?NTl2 coordination sphere with a stereo-chemically ‘active’ electron lone pair on the metal. The self assembly between the benzonitrile groups of one cubic cage structure with an adjacent one with a Tl?N short contact, by π-π stacking and weak hydrogen bonding interactions, results in the formation of a new interpenetrating thallium(I) supramolecular polymer. The thermal stability of 1 was studied by thermo gravimetric (TG) and differential thermal analyses (DTA). Nanostructures of thallium(III) oxide were prepared from a calcination process of compound 1 fine powder at 743 K. These nanostructures were characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). 相似文献
175.
Kamran AkhbariAli Morsali 《Polyhedron》2011,30(9):1456-1462
A new two-dimensional thallium(I) supramolecular polymer, [Tl2(μ3-9-Ac)(μ4-9-Ac)(H2O)]n (1) [9-HAc = 9-anthracene carboxylic acid], has been synthesized and characterized. The single-crystal X-ray data of compound 1 shows two types of TlI ions with coordination numbers of four and five. The thallium atoms have irregular coordination spheres, containing a stereo-chemically active lone pair with η5 Tl?C interactions in the vacant coordination sphere of the TlI ions, thus attaining total hapticities of 9 and 10 with O5Tl1?C5 and O4Tl2?C5 environments and Tl?π(centroid) distances of 3.308 and 3.251 Å, respectively. The thermal stability of 1 was studied by thermo gravimetric (TG) and differential thermal analyses (DTA). Different morphologies of thallium(III) oxide with a nano-structural surface were prepared from compound 1 powders and compound 1 micro-rods. These nano-structures were characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). 相似文献
176.
Reddy AS Kim S Jeong HY Jin S Qadir K Jung K Jung CH Yun JY Cheon JY Yang JM Joo SH Terasaki O Park JY 《Chemical communications (Cambridge, England)》2011,47(29):8412-8414
The facile synthesis of silica supported platinum nanoparticles with ultrathin titania coating to enhance metal-support interactions suitable for high temperature reactions is reported, as thermal and structure stability of metal nanoparticles is important for catalytic reactions. 相似文献
177.
It is shown that tight closure commutes with localization in any two-dimensional ringR of prime characteristic if eitherR is a Nagata ring orR possesses a weak test element. Moreover, it is proved that tight closure commutes with localization at height one prime ideals
in any ring of prime characteristic. 相似文献
178.
Sans résumé
Re?u le 20 octobre 1995 / Version revisée re?ue le 29 mai 1996 相似文献
179.
This paper deals with the local and abstract structure of Lie pseudogroups of infinite type. The formal aspect is considered in several cannonical ways, one of which is compatible with the known pathological behaviour of the exponential function. This defines a very precise program for the development of a convergent abstract theory of analytic Lie pseudogroups of infinite type. 相似文献
180.
M. Saeed Arayne Najma Sultana M. Kamran Zaman 《Accreditation and quality assurance》2008,13(8):431-432
The concept of good manufacturing practice (GMP) is not new; its roots are very old. The incidents that gave birth to the
concept of GMP are summarized in this article. The journey from the FDA toward GMP is highlighted in chronological order.
These regulations are mandatory for pharmaceutical industries in order to manufacture quality products. 相似文献