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Construction of Hybrid Bimetallic Uranyl Compounds Based on a Preassembled Terpyridine Metalloligand
Xianghe Kong Dr. Kongqiu Hu Dr. Lei Mei Dr. Qunyan Wu Zhiwei Huang Kang Liu Prof. Zhifang Chai Prof. Changming Nie Prof. Weiqun Shi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(6):2124-2130
Six hybrid uranyl–transition metal compounds [UO2Ni(cptpy)2(HCOO)2(DMF)(H2O)] ( 1 ), [UO2Ni(cptpy)2(BTPA)2] ( 2 ), [UO2Fe(cptpy)2(HCOO)2(DMF)(H2O)] ( 3 ), [UO2Fe(cptpy)2(BTPA)2] ( 4 ), [UO2Co(cptpy)2(HCOO)2(DMF)(H2O)] ( 5 ), and [UO2Co(cptpy)2(BTPA)2] ( 6 ), based on bifunctional ligand 4′-(4-carboxyphenyl)-2,2′:6′,2′′-terpyridine (Hcptpy) are reported (H2BTPA = 4,4′-biphenyldicarboxylic acid). Single-crystal XRD revealed that all six compounds feature similar metalloligands, which consist of two cptpy− anions and one transition metal cation. The metalloligand M(cptpy)2 can be considered to be an extended linear dicarboxylic ligand with length of 22.12 Å. Compounds 1 , 3 , and 5 are isomers, and all of them feature 1D chain structures. The adjacent 1D chains are connected together by hydrogen bonds and π–π interactions to form a 3D porous structure, which is filled with solvent molecules and can be exchanged with I2. Compounds 2 , 4 , and 6 are also isomers, and all of them feature 2D honeycomb (6,3) networks with hexagonal units of dimensions 41.91×26.89 Å, which are the largest among uranyl compounds with honeycomb networks. The large aperture allows two sets of equivalent networks to be entangled together to result in a 2D+2D→3D polycatenated framework. Remarkably, these uranyl compounds exhibit high catalytic activity for cycloaddition of carbon dioxide. Moreover, the geometric and electronic structures of compounds 1 and 2 are systematically discussed on the basis of DFT calculations. 相似文献
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Dr. Martha V. Escárcega‐Bobadilla Dr. Marta Martínez Belmonte Eddy Martin Eduardo C. Escudero‐Adán Prof. Dr. Arjan W. Kleij 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(8):2641-2648
A tetraoxo bis‐Zn(salphen) supramolecular host can bind various divalent metal salts, thereby providing access to trinuclear bifunctional systems that incorporate both Lewis acid sites and dynamically bound nucleophilic anions. The formation of these trinuclear species was investigated and their stability features were also determined. The application of these trinuclear complexes as bifunctional catalysts was evaluated in the formation of cyclic organic carbonates from epoxides and CO2. The catalytic data, in combination with control experiments, clearly demonstrate that these trinuclear compounds show much higher recycling potential compared to various control compounds and they can be used in up to five cycles without an observable loss in activity. Furthermore, this new recyclable catalytic system does not require any additives and can be applied under solvent‐free conditions. 相似文献
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Dipl.‐Chem. Steffen Styra Dr. Sandra González‐Gallardo Dr. Felix Armbruster Dr. Pascual Oña‐Burgos Dipl.‐Chem. Eric Moos Dr. Matthias Vonderach Priv.‐Doz. Dr. Patrick Weis Priv.‐Doz. Dr. Oliver Hampe Dipl.‐Chem. Anneken Grün Dipl.‐Chem. Yvonne Schmitt Prof. Dr. Markus Gerhards Dipl.‐Chem. Fabian Menges Dipl.‐Chem. Maximilian Gaffga Prof. Dr. Gereon Niedner‐Schatteburg Prof. Dr. Frank Breher 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(26):8436-8446
A series of bimetallic silyl halido cuprates consisting of the new tripodal silicon‐based metalloligand [κ3N‐Si(3,5‐Me2pz)3Mo(CO)3]? is presented (pz=pyrazolyl). This metalloligand is straightforwardly accessible by reacting the ambidentate ligand tris(3,5‐dimethylpyrazolyl)silanide ({Si(3,5‐Me2pz)3}?) with [Mo(CO)3(η6‐toluene)]. The compound features a fac‐coordinated tripodal chelating ligand and an outward pointing, “free” pyramidal silyl donor, which is easily accessible for a secondary coordination to other metal centers. Several bimetallic silyl halido cuprates of the general formula [CuX{μ‐κ1Si:κ3N‐Si(3,5‐Me2pz)3Mo(CO)3}]? (X=Cl, Br, I) have been synthesized. The electronic and structural properties of these complexes were probed in detail by X‐ray diffraction analysis, electrospray mass spectrometry, infrared‐induced multiphoton dissociation studies, cyclic voltammetry, spectroelectrochemistry, gas‐phase photoelectron spectroscopy, as well as UV/Vis and fluorescence spectroscopy. The heterobimetallic complexes contain linear two‐coordinate copper(I) entities with the shortest silicon–copper distances reported so far. Oxidation of the anionic complexes in methylene chloride and acetonitrile solutions at ${E{{0\hfill \atop 1/2\hfill}}}$ =?0.60 and ?0.44 V (vs. ferrocene/ferrocenium (Fc/Fc+)), respectively, shows substantial reversibility. Based on various results obtained from different characterization methods, as well as density functional theory calculations, these oxidation events were attributed to the Mo0/MoI redox couple. 相似文献
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Carlucci L Ciani G Maggini S Proserpio DM Visconti M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(41):12328-12341
The modular engineering of heterometallic nanoporous metal-organic frameworks (MOFs) based on novel tris-chelate metalloligands, prepared using the functionalised β-diketone 1,3-bis(4'-cyanophenyl)-1,3-propanedione (HL), is described. The complexes [M(III)L(3)] (M=Fe(3+), Co(3+)) and [M(II)L(3)](NEt(4)) (M=Mn(2+), Co(2+), Zn(2+), Cd(2+)) have been synthesised and characterised, all of which exhibit a distorted octahedral chiral structure. The presence of six exo-oriented cyano donor groups on each complex makes it a suitable building block for networking through interactions with external metal ions. We have prepared two families of MOFs by reacting the metalloligands [M(III)L(3)] and [M(II)L(3)](-) with many silver salts AgX (X=NO(3)(-), BF(4)(-), PF(6)(-), AsF(6)(-), SbF(6)(-), CF(3)SO(3)(-), tosylate), specifically the [M(III)L(3)Ag(3)]X(3)·Solv and [M(II)L(3)Ag(3)]X(2)·Solv network species. Very interestingly, all of these network species exhibit the same type of 3D structure and crystallise in the same trigonal space group with similar cell parameters, in spite of the different metal ions, ionic charges and X(-) counteranions of the silver salts. We have also succeeded in synthesising trimetallic species such as [Zn(x)Fe(y)L(3)Ag(3)](ClO(4))((2x+3y))·Solv and [Zn(x)Cd(y)L(3)Ag(3)](ClO(4))(2)·Solv (with x+y=1). All of the frameworks can be described as sixfold interpenetrated pcu nets, considering the Ag(+) ions as simple digonal spacers. Each individual net is homochiral, containing only Δ or Λ nodes; the whole array contains three nets of type Δ and three nets of type Λ. Otherwise, taking into account the presence of weak Ag-C σ bonds involving the central carbon atoms of the β-diketonate ligands of adjacent nets, the six interpenetrating pcu networks are joined into a unique non-interpenetrated six-connected frame with the rare acs topology. The networks contain large parallel channels of approximate hexagonal-shaped sections that represent 37-48% of the cell volume and include the anions and many guest solvent molecules. The guest solvent molecules can be reversibly removed by thermal activation with retention of the framework structure, which proved to be stable up to about 270°C, as confirmed by TGA and powder XRD monitoring. The anions could be easily exchanged in single-crystal to single-crystal processes, thereby allowing the insertion of selected anions into the framework channels. 相似文献
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Lea Bayer Dr. Bernhard S. Birenheide Dr. Felix Krämer Dr. Sergei Lebedkin Prof. Dr. Frank Breher 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(57):e202201856
The synthesis of heterobimetallic AuI/RuII complexes of the general formula syn- and anti-[{AuCl}( L1 ∩ L2 ){Ru(bpy)2}][PF6]2 is reported. The ditopic bridging ligand L1 ∩ L2 refers to a P,N hybrid ligand composed of phosphine and bipyridine substructures, which was obtained via a post-functionalization strategy based on Diels-Alder reaction between a phosphole and a maleimide moiety. It was found that the stereochemistry at the phosphorus atom of the resulting 7-phosphanorbornene backbone can be controlled by executing the metal coordination and the cycloaddition reaction in a different order. All precursors, as well as the mono- and multimetallic complexes, were isolated and fully characterized by various spectroscopic methods such as NMR, IR, and UV-vis spectroscopy as well as cyclic voltammetry. Photophysical measurements show efficient phosphorescence for the investigated monometallic complex anti-[( L1 ∩ L2 ){Ru(bpy)2}][PF6]2 and the bimetallic analogue syn-[{AuCl}( L1 ∩ L2 ){Ru(bpy)2}][PF6]2, thus indicating a small influence of the {AuCl} fragment on the photoluminescence properties. The heterobimetallic AuI/RuII complexes syn- and anti-[{AuCl}( L1 ∩ L2 ){Ru(bpy)2}][PF6]2 are both active catalysts in the P-arylation of aryldiazonium salts promoted by visible light with H-phosphonate affording arylphosphonates in yields of up to 91 %. Both dinuclear complexes outperform their monometallic counterparts. 相似文献
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Dr. Shu‐Ran Zhang Dr. Dong‐Ying Du Prof. Ke Tan Dr. Jun‐Sheng Qin Dr. Hui‐Qing Dong Prof. Shun‐Li Li Dr. Wen‐Wen He Prof. Ya‐Qian Lan Dr. Ping Shen Prof. Zhong‐Min Su 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(34):11279-11286
A new family of heterometal–organic frameworks has been prepared by two synthesis strategies, in which IFMC‐26 and IFMC‐27 are constructed by self‐assembly and IFMC‐28 is obtained by stepwise synthesis based on the metalloligand (IFMC=Institute of Functional Material Chemistry). IFMC‐26 is a (3,6)‐connected net and IFMC‐27 is a (4,8)‐connected 3D framework. The metalloligands {Ni(H4L)}(NO3)2 are connected by binuclear lanthanide clusters giving rise to a 2D sheet structure in IFMC‐28 . Notably, IFMC‐26‐Eu x Tb y and IFMC‐28‐Eu x Tb y have been obtained by changing the molar ratios of raw materials. Owing to the porosity of IFMC‐26 , Tb3+@IFMC‐26‐Eu and Eu3+@IFMC‐26‐Tb are obtained by postencapsulating TbIII and EuIII ions into the pores, respectively. Tunable luminescence in metal–organic frameworks is achieved by the two kinds of doping methods. In particular, the quantum yields of heterometal–organic frameworks are apparently enhanced by postencapsulation of LnIII ions. 相似文献