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During the reaction of [{Rh(μ‐Cl)(coe)2}2] (1) (coe = cis‐cyclooctene) with the tertiary phosphane tBu2PPh in a nitrogen atmosphere the square planar rhodium(II) complex trans‐[RhCl2(tBu2PPh)2] (2) was identified as a side product in moderate yield. 2 was synthesized in a defined manner in higher yields using a known procedure starting from [{Rh(μ‐Cl)(coe)2}2], tBu2PPh (molar ratio Rh:P of 1:2), and N‐chlorosuccinimide as the oxidizing agent in THF at room temperature. The molecular structure of 2 was determined by X‐ray crystallography. Additionally, to further confirm the molecular structure of trans‐[RhCl2(tBu2PPh)2], extensive DFT calculations were undertaken, which gave further evidence for its molecular structure. In contrast to the remarkable stability of 2 in the solid state, the investigation of solutions of this compound afforded hints at a dynamic equilibrium, which renders more difficult the collection of adequate NMR spectroscopic data for the title complex. [ABSTRACT FROM AUTHOR]

A procedure to synthesize (μ-hydroxo)bis-pentaaquarhodium(III) nitrate tetrahydrate [Rh2(H2O)8(μ-OH)2](NO3)4·4H2O from potassium hexachlororhodiate(III) is elaborated. The compound is isolated into the solid phase and structurally characterized. The crystallographic data are as follows: a = 5.8763(2) Å, b = 9.4749(4) Å, c = 9.6249(3) Å, α = 79.905(1)°, β = 84.324(1)°, γ = 82.922(1)°, space group P-1, Z = 1, ρcalc = 2.240 g/cm3. The compound is soluble in water, ethanol, and acetone. Hydrolysis takes place in concentrated nitric acid with the formation of mononuclear aqua- and aquanitrate complexes. Thermal decomposition of the salt at a temperature above 580 °C leads to the formation of a single product-rhodium(III) oxide. [ABSTRACT FROM AUTHOR]

The first filled Bi95+ polycation was isolated in the form of [RhBi9](AlCl4)4 crystals by dissolution of the solid precursor Bi12- xRh X13- x in the Lewis-acidic ionic liquid [BMIm]Cl·3.6AlCl3 (BMIm = 1-butyl-3-methylimidazolium) at 140 °C. In the monoclinic crystal structure [ P21/ n, a = 1217.5(2) pm, b = 1741.6(3) pm, c = 5085.7(7) pm, β = 90.117(8)°], the almost spherical [RhBi9]4+ polycations (approximate D3 h symmetry; Rh-Bi 276 ± 3 pm) show pronounced orientational disorder. Shiny black needles of Bi7RhI8 were obtained from the reaction of rhodium, bismuth, and BiI3 in the ionic liquid [BMIm]Cl ·1.3AlCl3 at 200 °C. Bi7RhI8 [ P21/ n, a = 943.10(1) pm, b = 1582.40(1) pm, c = 1645.40(1) pm, β = 95.48(1)°] is isostructural to Bi7RhBr8 and consists of molecular clusters [(RhBi7)I8]. The rhodium atom centers a pentagonal bipyramid of bismuth atoms, and the two apical bismuth atoms are in square-planar coordination of iodide ions. DFT-based calculations indicate strong bismuth-rhodium bonding with predominantly covalent character for both clusters. The electronic structure of the Bi95+ cage is notably modified by this interaction, but the characteristic bonding features of the host cluster with the D3 h configuration are still maintained. In Bi7RhI8, on the other hand, bonding is dictated by the spatial distribution of mutually repelling iodine atoms, and the Bi-Rh bonding is highly polar. [ABSTRACT FROM AUTHOR]

The first filled Bi95+ polycation was isolated in the form of [RhBi9](AlCl4)4 crystals by dissolution of the solid precursor Bi12- xRh X13- x in the Lewis-acidic ionic liquid [BMIm]Cl·3.6AlCl3 (BMIm = 1-butyl-3-methylimidazolium) at 140 °C. In the monoclinic crystal structure [ P21/ n, a = 1217.5(2) pm, b = 1741.6(3) pm, c = 5085.7(7) pm, β = 90.117(8)°], the almost spherical [RhBi9]4+ polycations (approximate D3 h symmetry; Rh-Bi 276 ± 3 pm) show pronounced orientational disorder. Shiny black needles of Bi7RhI8 were obtained from the reaction of rhodium, bismuth, and BiI3 in the ionic liquid [BMIm]Cl ·1.3AlCl3 at 200 °C. Bi7RhI8 [ P21/ n, a = 943.10(1) pm, b = 1582.40(1) pm, c = 1645.40(1) pm, β = 95.48(1)°] is isostructural to Bi7RhBr8 and consists of molecular clusters [(RhBi7)I8]. The rhodium atom centers a pentagonal bipyramid of bismuth atoms, and the two apical bismuth atoms are in square-planar coordination of iodide ions. DFT-based calculations indicate strong bismuth-rhodium bonding with predominantly covalent character for both clusters. The electronic structure of the Bi95+ cage is notably modified by this interaction, but the characteristic bonding features of the host cluster with the D3 h configuration are still maintained. In Bi7RhI8, on the other hand, bonding is dictated by the spatial distribution of mutually repelling iodine atoms, and the Bi-Rh bonding is highly polar. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of twenty new pentamethylcyclopentadienyl-rhodium and iridium complexes containing N^N and N^O-chelating chloroquine analogue ligands are described. The in vitro antimalarial activity of the new ligands as well as the complexes was evaluated against the chloroquine sensitive (CQS) NF54 and the chloroquine resistant (CQR) Dd2 strains of Plasmodium falciparum. The antimalarial activity was found to be good to moderate; although all complexes are less active than artesunate, some of the ligands and complexes showed better activity than chloroquine (CQ). In particular, rhodium complexes were found to be considerably more active than iridium complexes against the CQS NF54 strain. Salicylaldimine Schiff base ligands having electron-withdrawing groups (F, Cl, Br, I and NO2) in para position of the salicyl moiety and their rhodium complexes showed good antiplasmodial activity against both the CQS-NF54 and the CQR-Dd2 strains. The crystal structures of (η5-pentamethylcyclopentadienyl){N1-(7-chloroquinolin-4-yl)-N2-(pyridin-2-ylmethyl)ethane-1,2-diamine)} chlororhodium(iii) chloride and (η5-pentamethylcyclopentadienyl){(4-chloro-2-(((2-((7-chloroquinolin-4-yl)amino)ethyl)imino)methyl)phenolate)}chlororhodium(iii) chloride are reported. The crystallization of the amino-pyridyl complex (η5-pentamethylcyclopentadienyl){(N1-(7-chloroquinolin-4-yl)-N2-(pyridin-2-ylmethyl)ethane-1,2-diamine)}chloroiridium(iii) chloride in acetone resulted in the formation of the imino-pyridyl derivative (η5-pentamethylcyclopentadienyl){(N1-(7-chloroquinolin-4-yl)-N2-(pyridin-2-ylmethylene)ethane-1,2-diamine)}chloroiridium(iii) chloride, the crystal structure of which is also reported. [ABSTRACT FROM AUTHOR]

The synthesis and structural characterization of the new olefinic complex [Rh(η5-C5H5)(coe)2] ( 2) (coe = cis-cyclooctene) is reported. The title compound could easily be prepared in good yield by reaction of [{Rh(μ-Cl)(coe)2}2] ( 1) with an appropriate amount of thallium cyclopentadienide in THF at room temperature. Single crystals of 2 were grown from n-hexane and were analyzed by X-ray crystallography. In a similar manner the compound [Rh(η5-C5H5)(cod)] ( 4) (cod = cis, cis-1.5-cyclooctadiene) was obtained from [{Rh(μ-Cl)(cod)}2] and thallium cyclopentadienide in THF at room temperature and was characterized by spectroscopic means as well as by X-ray diffraction. [ABSTRACT FROM AUTHOR]

RhC30H25Cl2NO2P, orthorhombic P212121 (no. 19), a=7.6656(5) Å, b=16.6097(11) Å, c=20.9423(14) Å, V =2666.4(3) ų Z =4, Rgt(F)=0.0649, wRref(F²)=0.1632, T=100 K. [ABSTRACT FROM AUTHOR]

The N-heterocyclic carbene NHC/thione ligand precursors 1-[(3-R-2-thioxo-2 H-imidazol-1-yl)methyl]-3-R-2 H-imidazol-2-ium hexafluorophosphate, [HCSR]PF6 (R = methyl, benzyl) have been prepared and used in the synthesis of the complexes [Rh(CSR)(cod)][PF6] (R = methyl, benzyl; cod = 1,5-cyclooctadiene). The coordination and structural features of the novel ditopic NHC/thione ligands have been explored. [ABSTRACT FROM AUTHOR]