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941.
Sheng‐Run Zheng Xi‐Ling Wen Zi‐Meng Liu Tao Xie Jing‐Bo Tan Jun Fan Shuang‐Shuang Hou Wei‐Guang Zhang 《无机化学与普通化学杂志》2014,640(10):2057-2061
Two coordination polymers (CPs), namely, [Cu(Hptz)2(Hhba)2]n ( 1 ) [Hptz = 5‐(4‐pyridyl)‐1H‐tetrazole, H2hba = 2‐hydroxybenzoic acid] and [Zn3(ptz)2(hpa)2]n ( 2 ) (H2hpa = 2‐hydroxy‐2‐phenylacetic acid), were synthesized by solvothermal reactions. Both complexes were characterized by elemental analysis, infrared spectroscopy, powder X‐ray diffraction, thermogravimetric analysis, and single‐crystal X‐ray diffraction analysis. Compound 1 exhibits a 2D (4,4) network, where each layer connects to four adjacent layers to construct a 3D supramolecular framework. Compound 2 has a 3D framework structure composed of 1D SUBs, which are formed by both carboxyl and tetrazole groups. The complexes represent two rare examples of CPs constructed from Hptz and organic carboxyl acid ligands. Complex 2 exhibits intense, red‐shifted emissions in the visible region at room temperature. 相似文献
942.
Na[cyclo‐(P5tBu4)] ( 1 ) reacts with [FeBr2(CO)4] (2:1) to give the first homoleptic iron(II) complex [Fe{cyclo‐(P5tBu4)}2] ( 2 ) containing two tridentate cyclo‐(P5tBu4)– ligands. Thermolysis of 2 up to 500 °C produces a new phosphorus‐rich iron phosphide, calculated as FeP6 according to the mass change. 相似文献
943.
The TbIII compound [Tb(tci)(H2O)]n · n(DMF) ( 1 ) [H3tci = tri(2‐carboxythyl)isocyanurate, DMF = N,N′‐dimethylformamide] was synthesized by the reaction of terbium oxide, H3tci, and two drops of concentrated nitric acid in the presence of DMF and H2O. Single crystal X‐ray analysis reveals that it features a three‐dimensional (3D) framework based on infinite –Tb–COO–Tb– chains. The tci ligand in 1 links six different TbIII ions with its two carboxylate groups in μ2‐κ1O;κ2O,O′ mode and the third in μ2‐κ1O;κ1O′ mode. Thermal analysis reveals that it remains high thermal stability until 390 °C. Luminescence investigation shows that it emits characteristic green light of TbIII ions. 相似文献
944.
945.
Rüdiger W. Seidel Richard Goddard Jürgen Breidung Ernst‐G. Jäger 《无机化学与普通化学杂志》2014,640(10):1946-1952
A combined synchrotron X‐ray and density functional theory (DFT) study on the structure of a Jäger‐type N2O2 chelate complex was carried out. The ethoxy‐substituted bis(3‐oxo‐enaminato)cobalt(II) complex ( 1 ) was an original sample from the laboratory of the late Professor Ernst‐G. Jäger (University of Jena, Germany). Single‐crystal X‐ray analysis revealed essentially flat molecules of 1 , which are unsolvated and coordinatively unsaturated. The DFT calculations on the isolated molecule predict a planar structure for the non‐hydrogen atoms, which is a local minimum on the energy surface. The crystal packing is achieved through off‐set stacking (staircase arrangement), resulting in a herringbone pattern in the space group P212121. The structure of 1 is compared to known structures of related bis(3‐oxo‐enaminato)cobalt(II) complexes ( 2 – 4 ). Original bulk material of 1 was investigated by scanning electron microscopy (SEM), powder X‐ray diffraction (PXRD), melting point determination, and infrared (IR) spectroscopy. 相似文献
946.
Dian‐Feng Chen Feng Zhao Yue Hu Liu‐Zhu Gong 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(40):10939-10943
A combination of either ruthenium(II) or rhodium(II) complexes and quinine‐derived squaramide enables 3‐diazooxindoles, indoles, and nitroalkenes to undergo highly efficient asymmetric three‐component reactions, thus affording optically active 3,3′‐bis(indole)s through a consecutive C C bond‐forming sequence, which turned out to be applicable to the facile total synthesis of (−)‐folicanthine. 相似文献
947.
Jayachandran Jayakumar Kanniyappan Parthasarathy Yi‐Hsiang Chen Tai‐Hua Lee Shih‐Ching Chuang Chien‐Hong Cheng 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(37):10047-10050
A new method for the synthesis of highly substituted naphthyridine‐based polyheteroaromatic compounds in high yields proceeds through rhodium(III)‐catalyzed multiple C H bond cleavage and C C and C N bond formation in a one‐pot process. Such highly substituted polyheteroaromatic compounds have attracted much attention because of their unique π‐conjugation, which make them suitable materials for organic semiconductors and luminescent materials. Furthermore, a possible mechanism, which involves multiple chelation‐assisted ortho C H activation, alkyne insertion, and reductive elimination, is proposed for this transformation. 相似文献
948.
949.