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合成了10种未见文献报道的m eso-四(对烷氧基苯基)卟啉合银配合物,研究了其合成、分离、纯化方法.用红外光谱、紫外-可见光谱、核磁共振氢谱、质谱和元素分析等对各个化合物的结构进行了表征.研究了其荧光性能,用差示扫描量热仪和偏光显微镜对其液晶性质进行了研究,发现10个配合物均具有液晶性.  相似文献   

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The aromatic metallole dianions are important metallaaromatic compounds because of their various reactivities and extensive synthetic applications. Herein we report the reactions of dilithionickelole with MgCl2, EtAlCl2, Cp*ScCl2, Cp*LuCl2 and Pt(COD)Cl2 (COD=1,5-cyclooctadiene) affording a series of Ni/M heterobimetallic complexes of the general formula (η4−C4R4M)Ni(COD), in which the metalloles act as diene ligands, as suggested by single-crystal X-ray, NMR and theoretical analyses. In these reactions, two electrons of the nickelole dianion transferred to Ni, representing different reactivity compared with main-group metallole dianions.  相似文献   

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The reactions of silver(I) with isocyclam, scorpiand,trans-Me2[14]anN4, cis-Me6[14]anN4,(N-Me)Me2py[14]anN4 and py[12]anN4 were investigated.The stability constant of the Ag(I) complex with py[12]anN4 was determined. The aqueous solutions of the silver(II) complexes with the 14-membered ligands were obtained, and characterized by means of UV-VIS and CVA measurements. The Ag2+ ion does not form a five-coordinate complex with scorpiand. The formal potentials of the Ag(II)/Ag(I) system in the presence of scorpiand, trans-Me2[14]anN4, cis-Me6[14]anN4 and(N-Me)Me2py[14]anN4 were determined. The mechanism is also proposedfor the electroreduction of the silver(II) complexes with these compounds on a platinum electrode in aqueous solution.  相似文献   

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Abstract

The potential of thiotriazoles and thiotetrazoles in coordination chemistry towards gold and silver derivatives still remains largely unfulfilled. These substrates can function as ideal S,N donor ligands and form covalent or coordinative bonds with gold and silver. Relying on this, a comprehensive overview in this field is given in the article and basic principles are discussed.

GRAPHICAL ABSTRACT   相似文献   

9.
By employing silver salts with a weakly coordinating anion Ag[A] ([A]=[FAl{OC12F15}3], [Al{OC(CF3)3}4]), two phosphaalkynes could be coordinated side‐on to a bare silver(I) center to form the unprecedented homoleptic complexes [Ag(η2‐P≡CtBu)2][FAl{OC12F15}3] ( 1 ) and [Ag(η2‐P≡CtBu)2][Al{OC(CF3)3}4] ( 2 ). DFT calculations show that the perpendicular arrangement in 1 is the minimum energy structure of the coordination of the two phosphaalkynes to a silver atom, whereas for 2 a unique square‐planar coordination mode of the phosphaalkynes at Ag+ was found. Reactions with donor molecules yield the trigonally planar coordinated silver salts [((CH3)2CO)Ag(η2‐P≡CtBu)2][FAl{OC12F15}3] ( 3 ) and [(C7H8)2Ag(η2‐P≡CtBu)][FAl{OC12F15}3] ( 4 ). All of the compounds were comprehensively characterized in solution and in the solid state.  相似文献   

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The synthesis and full characterization of new air-stable AgI and CuI complexes bearing structurally bulky expanded-ring N-heterocyclic carbene (erNHC) ligands is presented. The condensation of protonated NHC salts with Ag2O afforded a collection of AgI complexes, and their first use as ligand transfer reagents led to novel isostructural CuI or AuI complexes. In situ deprotonation of the NHC salts in the presence of a copper(I) source, provides a library of new CuI complexes. The solid-state structures feature large N-CNHC-N angles (118–128°) and almost identical angles between the aryl groups on the nitrogen atoms and the plane of the N-C-N unit of the carbene (i.e. torsion angles close to 0°). Among the steric parameters, the percent buried volume (%Vbur) values span easily in the 50–57 % range, and that one of (9-Dipp)CuBr complex (%Vbur=57.5) overcomes to other known erNHC–metal complexes reported to date. Preliminary catalytic experiments in the copper-catalyzed coupling between N-tosylhydrazone and phenylacetylene, afforded 76–93 % product at the 0.5–2.5 mol % catalyst loading, proving the stability of CuI erNHC complexes at elevated temperatures (100 °C).  相似文献   

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Solutions of silver and lithium tetrafluoroborate in acrylonitrile, over a range ofconcentrations between 0.5 and 4 mol-kg–1, have been studied byFourier-transform Raman spectroscopy. The spectral regions studied include the solvent(C=dN) fundamental and the anion B-F symmetric stretching band. In AgBF4solutions the absence of ionic pairing was demonstrated and the anion 1(A 1)remains as a single narrow band located at 764.7±0.1 cm–1. Consequently, thesilver ion solvation number does not change in the range of concentrations studied,having a constant value of 3.54±0.10. However, a high level of ionic pairingwas observed in the corresponding solutions of LiBF4. Three components weredetected in the tetrafluoroborate 1(A 1) band located at 766.0±0.4, 773.4±1.1,and 782.7±0.9 cm–1, and assigned to spectroscopically free anions, ion pairs,and dimers, respectively. The solvation number of the lithium ion, which shouldbe three in the limit of infinite dilution, decreases as the salt concentrationincreases as a result of the ionic pairing. However, the ionic pairing of LiBF4 inacrylonitrile is less than that previously observed in lithiumtrifluoromethanesulfonate (triflate) or lithium perchlorate.  相似文献   

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合成了2个新的烯唑醇铜和银配合物:[CuL4Cl2](1),[AgL2]NO3(2)(L=diniconazole)。通过元素分析、红外光谱和X-ray单晶衍射对其结构进行了表征。结构分析表明,1属三斜晶系,P1空间群,晶胞参数为a=0.882 3(7)nm,b=1.370 5(10)nm,c=1.516 4(11)nm,α=91.507(11)°,β=97.356(9)°,γ=107.683(9)°。2属单斜晶系,P21/c空间群,晶胞参数为a=1.229 2(3)nm,b=1.272 1(3)nm,c=2.431 7(5)nm,β=98.694(3)°。1和2都由分子间氢键连接成一维链结构。  相似文献   

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A silver‐catalyzed amidiniumation of N‐propiolic formamidines for the synthesis of novel enamine amido carbene precursors is reported. Isolation of a first silver intermediate in silver‐catalyzed amidiniumation of alkynes and other organogold intermediates supports our proposed mechanisms. Several control experiments reveal the unexpected effects of both HOTf and substrate substituents on the choice of either a π or σ,π silver activation mode and the cyclization fashion. Bis(hydroxyimidazol)ium salts were obtained through an unprecedented umpolung of propiolamides. The byproduct Ag2O as either an oxidant or silver source promotes the syntheses of N‐heterocyclic carbene (NHC) precursors or Ag/NHC complexes.  相似文献   

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Two cyclopropyl allenylidene complexes [Ru]=CCC(R)(C3H5) ([Ru]=[RuCp(PPh3)2], Cp=Cyclopentadienyl; R=thiophene ( 2a ) and R=Ph ( 2b )) are prepared from the reactions of [Ru]Cl with the corresponding 1‐cyclopropyl‐2‐propyn‐1‐ol in the presence of KPF6. Thermal treatment, halide‐anion addition, and palladium‐catalyzed reactions of 2a and 2b all lead to a ring expansion of the cyclopropyl group, giving the vinylidene complexes 4a and 4b , respectively, each with a five‐membered ring. This ring expansion proceeds by C C bond formation between Cβ of the cumulative double bond and a methylene group of the cyclopropyl ring. In the reaction of 2a with pyrrole, consecutive formation of two C C bonds, one between C‐2 of pyrrole and Cγ of 2a and the other between C‐3 of pyrrole and Cα, results in the formation of 6a . The reaction proceeds by addition of pyrrole and 1,3‐proton shifts. The hydrogenation of 2a by NaBH4 is carried out in different solvents. The cumulative double bonds are reduced regioselectively to give a mixture of 7a and 8a . Interestingly, use of different solvents leads to different ratios of 7a and 8a . Presence of a protic solvent like methanol in dichloromethane or chloroform solution increases the yield of 8a , thus revealing that both the rates of hydroboration and deboronation increase. The structures of two new complexes 4a and 6a have been firmly established by X‐ray diffraction analysis.  相似文献   

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萘啶酮的单核和双核银配合物的合成与晶体结构   总被引:2,自引:0,他引:2       下载免费PDF全文
合成了萘啶酮的单核和双核银配合物Ag2(L1)2(HL1=5,7-二甲基-1,8-萘啶-2-酮) (1)和[Ag(HL2)(PPh3)2]·2H2O(H2L2=1,8-萘啶-2,7-二酮) (2)。并通过元素分析,红外光谱及X-射线单晶衍射对其进行了结构表征。配合物1的晶体属单斜晶系,P1空间群。中心金属银为三配位T型几何构型,Ag-Ag间距离为0.274 8(2) nm,具有强的Ag…Ag作用。配合物2的晶体属三斜晶系,P21/n空间群。银与1个氮原子及2个磷原子形成三配位结构。  相似文献   

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Pyrrole‐modified subporphyrins bearing a non‐pyrrolic cyclic unit, subporpholactone, subporpholactam, and imidazolosubporphyrin were newly synthesized. They show subporphyrin‐like absorption and fluorescence spectra that are red‐shifted in the order of subporpholactam<subporpholactone<imidazolosubporphyrin. Metalation of the imidazolosubporphyrin with (pentamethylcyclopentadienyl)iridium(III) dichloride dimer gave a complex, in which the iridium(III) atom was attached at the peripheral nitrogen atom of the imidazole moiety and the ortho‐position of the meso‐phenyl group. Reaction of this complex with diphenylacetylene gave different products depending on the used additive; a phenyl‐rearranged product in the presence of NaBArF4 (ArF=3,5‐bis(trifluoromethyl)phenyl) and two isomeric carbene complexes in the presence of KPF6.  相似文献   

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在有机溶剂中,我们设计合成了4种配合物:[Cu2Cl4pz*2](1),[Cu2Cl4(L2)2](2),[CuCl(L2)2H2O]Cl.H2O(3),[Ag(L3)2]NO3(4)(pz*=3,5-二甲基吡唑;L2=二吡唑甲烷;L3=4-碘-3,5-二甲基吡唑)。通过元素分析、红外光谱、紫外光谱、X-ray粉末和X-ray单晶衍射方法对其结构进行了表征,分析了其光谱及结构特征。结构分析表明,吡唑烷均采取二齿配位模式,配合物1、3和4中金属的配位数分别为五、六和二;配合物2中则存在2种不同配位模式的中心铜离子。并用Gaussian03量子化学程序包,采用密度泛函理论(DFT)中的B3LYP方法,研究了3个铜配合物的稳定性和电荷分布。  相似文献   

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The reactivity of amidinatotetrylenes of the type E(tBu2bzm)R1 (E=Si, Ge; tBu2bzm=N,N′-bis(tertbutyl)benzamidinate; R1=alkyl or aryl) with the chromium Fischer alkynylcarbene complexes [Cr{C(OEt)C2R2}(CO)5] (R2=Ph; ferrocenyl, Fc) has been studied. At room temperature, two different reaction pathways have been identified: (a) attack of the amidinatotetrylene to the alkynyl C2 atom (γ-attack), which leads to σ-allenyl complexes in which the original Ccarbene atom maintains its attachment to the Cr(CO)5 and OEt groups (compounds 3 ), and (b) attack of the amidinatotetrylene to the Ccarbene atom (α-attack), which ends in σ-allenyl complexes in which the original Ccarbene atom is not attached to the metal atom and has been inserted into an E−N bond of the amidinatotetrylene forming an E-C-N-C-N five-membered ring (compounds 4 ). It has been found that compounds 3 are thermodynamically less stable than their corresponding 4 isomers and that some of the former (E=Ge; R1=CH2SiMe3) can be transformed into the latter upon heating. At high temperatures (>70 °C) the reactions involving bulky amidinatotetrylenes (R1=Mes, tBu) end in the carbene-substitution products [Cr{E(tBu2bzm)R1}(CO)5].  相似文献   

19.
用abinitioMO法计算了6种氯代四唑银的配合物模型,结果表明,π型配合物难以存在.在σ型配合物中银的配位使四唑环上单键增长、体系更不稳定.环N(2)(或N(3))原子较N(1)(或N(4))原子易于与金属成键;N(2)型配合物较N(1)型配合物稳定.预示5氯四唑银配合物将以2∶1(配体:金属原子)N(2)型为主.  相似文献   

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Herein, we report the preparation of a new unsymmetrical, bis(thiophosphinoyl)‐substituted dilithio methandiide and its application for the synthesis of zirconium‐ and palladium‐carbene complexes. These complexes were found to exhibit remarkably shielded 13C NMR shifts, which are much more highfield‐shifted than those of “normal” carbene complexes. DFT calculations were performed to determine the origin of these observations and to distinguish the electronic structure of these and related carbene complexes compared with the classical Fischer and Schrock‐type complexes. Various methods show that these systems are best described as highly polarized Schrock‐type complexes, in which the metal–carbon bond possesses more electrostatic contributions than in the prototype Schrock systems, or even as “masked” methandiides. As such, geminal dianions represent a kind of “extreme” Schrock‐type ligands favoring the ionic resonance structure M+? CR2? as often used in textbooks to explain the nucleophilic nature of Schrock complexes.  相似文献   

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