Synthesis of Norcantharidin Complex Salts

A new series of norcantharidin salt derivatives was designed and synthesized in good yield. The compounds structures were characterized by ¹H‐NMR, ¹³C‐NMR, and IR spectra. These norcantharidin salts 5 exhibit good antitumor activity against both liver cancer and colon cancer cell lines in vitro, which seems to direct a right trend for the modification on cantharidin structure.     

Synthesis and Utility of Neptunium(III) Hydrocarbyl Complex

To extend organoactinide chemistry beyond uranium, reported here is the first structurally characterized transuranic hydrocarbyl complex, Np[η⁴‐Me₂NC(H)C₆H₅]₃ ( 1 ), from reaction of NpCl₄(DME)₂ with four equivalents of K[Me₂NC(H)C₆H₅]. Unlike the U^III species, the neptunium analogue can be used to access other Np^III complexes. The reaction of 1 with three equivalents of HE₂C(2,6‐Mes₂‐C₆H₃) (E=O, S) yields [(2,6‐Mes₂‐C₆H₃)CE₂]₃Np(THF)₂, maintaining the trivalent oxidation state.     

Complex Salts of Lanthanide(III) Nitrates from Di­pyridylamine: Preparation,Structural, and Thermoanalytical ­Investigation

The reaction of a lanthanide(III) nitrate (Ln = Pr, Nd) with the base 2, 2′‐dipyridylamine (dpamH) afforded two very stable microcrystalline compounds. These compounds were characterized as complex salts with the general formula [Ln(NO₃)₆] · 3[dpamH‐H⁺] · H₂O, where the dpamH ligand is not coordinated, but exists in its protonated form serving as counterion (dipyridylammonium cation), as it was revealed by single‐crystal X‐ray diffraction studies. Each one of the nitrate ions is coordinated, however, in a bidentate manner with the lanthanide(III) ion, which obtains coordination number twelve. All organic dpamH‐H⁺ cations are arranged in two columns parallel to the a axis of the cell forming pairs of almost parallel cationic molecules at a distance of about 3.5 Å. Inside each pair the molecules interact by strong π–π interactions. The water molecules, arranged between the inorganic anions [Ln(NO₃)₆]^3–, bridge them by strong hydrogen bonds, involving the water proton and one nitrate oxygen. The lattice can be described as made from successive organic and inorganic alternating parallel columns interacting between them with strong hydrogen bonds. The thermal stability and decomposition mode of the two lanthanide compounds were studied by the simultaneous TG/DTG‐DTA technique and compared with the starting hexahydrate lanthanide(III) salts and the dipyridylamine.     

新型抗糖尿病铬(III)配合物的合成和生物活性及机理探究

为了寻找新型的抗糖尿病分子,以苯乙双胍为前体,制备了苯乙双胍铬（III）配合物.通过元素分析、摩尔电导率、电喷雾质谱、红外光谱、紫外可见光谱和核磁共振波谱对配合物的结构进行了表征,并研究了配合物在不同温度、不同pH值下溶液的稳定性、与H₂O₂的反应性和形貌.同时,构建了糖尿病C57小鼠模型,研究了其生物活性和毒性.结果证明,配合物对其活性指标均有好的抑制作用,保留了苯乙双胍的降糖性质,对机体是无毒的,并且通过MTT（3-（4,5-二甲基噻唑-2）-2,5-二苯基四氮唑溴盐）实验说明配合物的生物相容性较好,实现了金属配合物降糖与控脂的多功能化应用.在此基础上,通过光谱法研究了配合物与胰高血糖素的相互作用,表明配合物对胰高血糖素是静态猝灭以较强的作用力结合,条件结合常数为1.29×10⁵ L·mol^-1,结合位点数约为1,初步提出了配合物的新的降糖机制.     

Isomerism in the Terbium(III) Trifluoroacetate Trihydrate Dimer

Precision Xray diffraction analysis of a perfect single crystal showed that the molecule of terbium(III) trifluoroacetate trihydrate is a combination of two isomers (monomeric form), Tb(CF₃COO)₃(H₂O)₃ and Tb(CF₃COO)₂(CF₃COOH)(H₂O)₂(OH) with a statistical weight of 0.5. Based on precision Xray diffraction analysis, the statistical composition of the compound resulting from neutralization of terbium(III) hydroxide with trifluoroacetic acid is Tb(CF₃COO)_2.5(CF₃COOH)_0.5(H₂O)_2.5(OH)_0.5. The presence of the CF₃COOH molecule and the OH^- group is also confirmed by IR and ¹H NMR spectra, respectively. The presence of 18 rather than the anticipated nine Stark components of the ⁵D₄⁷F₀ transition of the Tb³⁺ ion can be explained in terms of both a static and a dynamic model. In the static case, the compound can be represented as a combination of equal fractions of two isomers; hence the doubled number of Stark components. In this case, the molecule of the dimer remains statistically centrosymmetric. In the dynamic version, migration of a proton across the dimer from one of the water molecules to the nearest monodentate anion CF₃COO^- and back leads to an electron density redistribution in the vicinity of each Tb³⁺ ion within the dimer, the crystallographic equivalence of their positions being preserved. However, Xray structure analysis cannot distinguish between these two cases. In any case, the observed isomerism in terbium(III) trifluoroacetate trihydrate removes discrepancies between the data of Xray structural and luminescent analyses.     

Complex antimony(III) oxohalides: Synthesis and physicochemical properties

Complexes of the formula MSb₂BrF₄O (M = K, Rb, and NH₄) were obtained from aqueous solutions of SbF₃ and MBr and examined by chemical analysis, X-ray diffraction, thermal analysis, and IR, Raman, and ¹⁹F NMR spectroscopy. It was found that the red reflectance is 74–97% and the UV reflectance is 7–15%. The highest averaged reflectance (93%) was observed for KSb₂BrF₄O. The decomposition temperatures of MSb₂BrF₄O (M = K, Rb, and NH₄) are 230, 197, and 223°C, respectively.     

微波辐射法合成喹喔啉铱（Ⅲ）配合物及其发光性质

采用微波辐射加热方法,将2,3-二苯基喹喔啉（DPQ）与水合三氯化铱（IrCl3•H2O）反应,合成了一种新型三环喹喔啉铱配合物[Ir(DPQ)3],通过元素分析,1H NMR和质谱方法对配合物结构进行了表征,并初步研究了配合物的吸收光谱和荧光光谱。结果表明,配合物Ir(DPQ)3在387和458nm处存在单线态1MLCT（金属到配体的电荷跃迁）和三线态3MLCT的吸收;在634nm 处有较强的金属配合物三线态的磷光发射。     

Efficient Pathway for the Preparation of Aryl(isoquinoline)iodonium(III) Salts and Synthesis of Radiofluorinated Isoquinolines

Iodonium compounds play a pivotal role in ¹⁸F‐fluorination of radiopharmaceuticals containing non‐activated arenes. However, preparation of these species is limited to oxidation conditions or exchange with organometallics that are prepared from aryl halides. Herein we describe a novel “one‐pot” process to assemble aryl(isoquinoline)iodonium salts in 40–94 % yields from mesoionic carbene silver complex and Aryl‐I‐Py₂(OTf)₂. The method is general, practical, and compatible with well‐functionalized molecules as well as useful for the preparation of a wide range of ¹⁸F‐labeled isoquinolines resulting in up to 92 % radiochemical conversion. As proof of concept, a fluorinated isoquinoline alkaloid, ¹⁸F‐aspergillitine is prepared in 10 % isolated radiochemical yield from the corresponding phenyl(aspergillitine)iodonium salt.     

四中位（邻烷基）苯基卟啉及其高铁络合物的合成及光谱性质

合成了６种不同大小的烷基取代的四中位（邻烷基）苯基卟啉Ｔ＿（Ｏ－Ｒ）ＰＰＨ＿２及其高铁络合物Ｔ＿（Ｏ－Ｒ）ＰＰＦｅＣｌ（Ｒ＝ＣＨ＿３，Ｃ＿２Ｈ＿５，ｎ－Ｃ＿３Ｈ＿７，ｉ－Ｃ＿３Ｈ＿７，ｎ－Ｂｕ，ｔ－Ｂｕ），除Ｒ＝ＣＨ＿３外，其它５种是文献未曾报道过的新化合物。测定了它们的核磁共振谱、红外及电子光谱，并讨论了它们的结构与光谱性质的关系．     

Synthesis and Structure of Heterometallic Bi(III) Complex with Diethylenetriaminepentaacetic Acid

A new heterometallic Bi(III) complex with diethylenetriaminepentaacetic acid anion (Dtpa)⁵⁻ of the composition [Co(Tsc)₃]₂[Bi(Dtpa)]₂SO⁴ ⋅ 6H₂O (I) (Tsc is thiosemicarbazide) is synthesized and its crystal structure is determined. The complex consists of the [Co(Tsc)₃]³⁺ cations, [Bi(Dtpa)]²⁻ and SO ₄ ²⁻ anions, and crystallization water molecules. The SO ₄ ²⁻ ion and two water molecules are randomly disordered over two positions. In the complex cation [Co(Tsc)₃]³⁺, the metal polyhedron has fac-form. The carboxyl groups of octadentate (Dtpa)⁵⁻ ligand in the [Bi(Dtpa)]²⁻ anion are fully deprotonated. The coordination polyhedron of the Bi atom is a distorted bicapped trigonal prism. Thermogravimetric analysis of complex I indicates that its decomposition occurs through several stages, i.e., dehydration, burning of organic ligands, and the formation of inorganic residue.__________Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 6, 2005, pp. 446–454.Original Russian Text Copyright © 2005 by Bulimestru, Petrenko, Gulea, Gdaniec, Simonov.     

Synthesis and Oxidative Stability of an Anionic Perfluoroethyl Cobalt(III) Complex

Upon reaction of the versatile tris(perfluoroethyl) cobalt(III) precursor [fac-(MeCN)₃Co(C₂F₅)₃] with potassium tris(pyrazolyl)borate (KTp) in the presence of a tetraphenylphosphonium salt, κ²- and κ³- adducts of the scorpionate ligand with cobalt were observed. Heating this mixture to 50 °C induced complete κ³-coordination of the Tp ligand to cobalt to afford the anionic complex [PPh₄][(κ³-Tp)Co(C₂F₅)₃] in 81 % yield. This new fluoroalkyl cobalt complex was characterized by NMR and UV-Vis spectroscopies, X-ray crystallography, and cyclic voltammetry. The oxidation of [PPh₄][(κ³-Tp)Co(C₂F₅)₃] occurs at much less-positive potentials relative to the related [(MeCN)₃Co(C₂F₅)₃] and [(tpy)Co(C₂F₅)₃] derivatives.     

Complex rhodium(III) salts with isonicotinic acid: Synthesis and study

A method for the synthesis of complex rhodium(III) salts of the trans-dichlorotetramine series with isonicotinic acid (iso-NicH) was developed. Three new compounds were isolated: [Rh(iso-NicH)₃(iso-Nic)Cl₂] (I), [Rh(iso-NicH)₄Cl₂]Cl · 4H₂O (II), and Na3[Rh(iso-Nic)₄Cl₂] · 9H₂O (III). The compounds synthesized were characterized by elemental analysis, X-ray phase analysis, and IR spectroscopy. The crystal structures of salts II and III were determined by X-ray diffraction analysis. The thermal properties of all compounds were studied by the DTA method. The intermediate and final thermolysis products were isolated and characterized.     

Synthesis and Some Transformations of Complex Salts of Bis-o-dicarbollyliron(II), -cobalt(II), and -nickel(II)

The complex salts [(o-C2B9H11)2M³⁺]₂M'²⁺·4bipy, where M = Fe, Co, or Ni, M' = Fe, Co, Ni, Cu, Mn (M M'), and bipy is 2,2'-bipyridyl, were synthesized. The salts with M = Ni decompose to give 3-(2,2'-bipyridyl)-3,1,2-nickelacarborane, when refluxed in alcohol, and to give 2-(2,2'-bipyridyl)-2,1,7-nickel acarborane, when refluxed in dodecane (216°C).     

Complex Chemical Synthesis of Unstable Sulfinyl- and Sulfonyl Derivatives of Phosphorus(III)

Abstract

The phosphorus(III) homologues of sulfonamides, R′₂P-S(O)₂R, are hitherto unknown. This is also in the case of phosphorus(V) derivatives: sulfinylphosphinates undergo symmetrization reactions to the homogeneous anhydrides. Sulfinylphosphinites, the O-isomers of sulfonylphosphanes, can only be built up as unstable ligands in the coordination sphere of transition metals, where the Br(CO)₄Mn-fragment seems to be more stable than the (CO)₅M-fragment (M=Cr, Mo, W). Thus, we now synthesized the iodo complexes I(CO)₄Mn[P(C₆H₅)₂X] (X=H, SiMe₃) as suitable starting material for the synthesis of SO-, SO₂-, RSO- and RSO₂-derivatives of coordinated phosphorus(III). Because of the surprising cis-position of the iodo and silyl group (x-ray structure analysis) the silyl-phosphane complex 2 is also of high interest to 1,2-elimination reactions to give metal-phosphorus double bonds.