Synthesis Of Rhenium Research Articles

Coordination mode of cyclohex-1-enylolonium cation and bridging pyridyl derivatives as gem-diol chelates to rhenium(I) and (VII)

Rhenium(I) and (VII) complexes with cyclohex-1-enylolonium cation and bridging pyridyl derivatives are reported. Additionally, the CO-bridged pyridyl and their related compounds have shown interesting behaviour in their reactivity towards compounds containing two amino groups. The unusual cationic compound: (2,6-diaza-cyclohex-1-enylolonium)2-aza-benzoate (H2den), was isolated from the reaction mixture of 1,2-di(pyridin-2-yl)ethane-1,2-dione with propane-1,3-diamine in methanol. The latter ligand: H2den, was used in the synthesis of rhenium(I) complex in its reaction with [Re(CO)5Cl] that gave rise to novel rhenium(I) complex fac-[Re(CO)3(Hhdm)] (1). The surprising aspect in the formation of (1) is the modification of H2den which was stabilized into a coordinated six-membered pyrimidine ring, 1,4,5,6-tetrahydropyrimidin-2-yl)di(pyridin-2-yl)methanol (H2hdm) chelate. The derived ligand acts as a tridentate monoanionic N2,O-donor ligand towards the fac-[Re(CO)3]+ core. Surprisingly, the 2-aza-benzoate counter-ion that was present in the used ligand is not displayed in the crystal structure of complex 1, and might have been stabilized into 2-aza-benzoic acid (picolinic acid). The reaction of the potential tridentate N2,O-donor ligand 2,2′-dipyridylketone (dpk) with trans-[ReOI2(OEt)(PPh3)2] led to the isolation of [ReO3(dpk·OH)] (2). The ligand H2den and the rhenium complexes were spectroscopically characterized, and the structures of H2den, 1 and 2 were established by X-ray diffraction.

Synthesis and Properties of Macrocyclic Complexes Ruthenium Azerbaijan State University of Oil and Industry

Synthetic methods have been developed and Ru (IV) complex compounds with five types of donor ligands have been prepared: phenanthroline, nicotinic acid amide, imidazole, benzimidazole and their derivatives, and phthalocyanine. New method for the synthesis of rhenium and ruthenium phthalocyanines is proposed, which is distinguished by its availability and high yields. It is established that because of synthesis only one form of ruthenium phthalocyanine is formed, which can be attributed to the PcRuO structure based on physical and chemical studies.

Synthesis of Rhenium(I) Tricarbonyl Complexes with Carbohydrate‐Pendant Tridentate Ligands and Their Cellular Uptake

AbstractTwelve [ReIL(CO)3]n+ complexes with various carbohydrate‐pendant ligands L have been prepared and their uptake into HeLa S3 cells were investigated. The ligand library includes: (i) glucose/galactose as the carbohydrate group; (ii) bis(2‐pyridylmethyl)amine (DPA), bis(2‐quinolylmethyl)amine (DQA), or N‐(2‐pyridylmethyl)glycine (NPG) as the metal binding component; and (iii) an ethylene chain as a linker between the metal binding site and the O/C‐glycosides. Microwave induced plasma mass spectroscopy (MIP‐MS) measurements revealed that all complexes were extensively incorporated into the HeLa cells over a 24 h period, and the DQA complexes showed the highest uptake of all the complexes in the series. However, in comparison to the corresponding Re complexes without the pendant carbohydrate functions (prepared with the related ligands LDPA, LDQA, and LNPG), only the NPG complexes exhibited carbohydrate enhanced cellular uptake. Considering their water solubility and cellular uptake properties, the NPG complexes containing an O‐glycoside group (L1 and L′1) are the best candidates for enhancing cellular uptake of metal ions. Microscopic analysis with PC‐12 cells in the presence of thefluorescent complex [Re(L′7)(CO)3]Cl, revealed that the complex stays in the cell cytosol and cannot penetrate into the nucleus.

One and two photon fluorescent complexes of rhenium and their technetium analogues

The synthesis of rhenium and 99m-technetium complexes of dipyrazolemethanecarboxylates directly from the tetroxometallates is reported together with a 'one pot' synthesis of mixed ligand M(V) complexes. The rhenium complexes in all three oxidation states show strong fluorescence when the pyrazole groups have aromatic substituents with emission around 330 nm with both one and two photon excitation. The emission lifetimes of the complexes and free ligands differ considerably.

Two New Imidazole‐Based Heteroscorpionate Ligands

AbstractThe syntheses of two novel imidazole‐based N,N,Oand N,N,S ligands, 2,2‐bis(N‐methylimidazol‐2‐yl)ethanol (Hbmie) and lithium bis(N‐methylimidazol‐2‐yl)dithioacetate Li[bmidta], are described. The coordination properties of the two new ligands are studied by the synthesis of rhenium(I) and ruthenium(II) complexes. Single crystal X‐ray diffraction analyses of Hbmie, Li[bmidta] together with bis(N‐methylimidazol‐2‐yl)methane (bmim) and [Re(bmie)(CO)3] are provided, too.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Rhenium(I) bridged porphyrin dyads with heteroatom substituted cores: Synthesis and fluorescence properties

Synthesis of Rhenium(I) bridged three cyclic dyads containing two 21-thiaporphyrins or two 21-oxaporphyrins or one 21-thia and one 21-oxaporphyrin using cis-pyridyl 21-thia and 21-oxaporphyrin building blocks is reported. The fluorescence properties studied by both steady state and time-resolved fluorescence techniques on dyad containing one 21-thia and one 21-oxaporphyrin unit indicated a possibility of energy transfer from 21-oxaporphyrin unit to 21-thiaporphyrin unit.

Synthesis and electronic properties of mononuclear osmium(II) and rhenium(I) complexes containing ligands derived from [2,3-a:3 ′,2 ′-c]dipyridophenazine (ppb)

An improved method for the synthesis of the polypyridyl ligand [2,3-a:3 ′,2 ′-c]dipyridophenazine (ppb) is reported. In addition, the syntheses of the new ppb-based ligands L (L=[2,3-a:3 ′,2 ′-c]dipyridophenazine, [2,3-a:3 ′,2 ′-c]dipyrido-6,7-dimethylphenazine, [2,3-a:3 ′,2 ′-c]dipyrido-6,7-dichlorophenazine, [2,3-a:3 ′,2 ′-c]dipyrido[1,2-e]benzophenazine, [2,3-a:3 ′,2 ′-c:3″,2″-e]tripyridoquinoxaline and [2,3-a:3 ′,2 ′-c]dipyrido-5-methylphenazine) are detailed. The complexes [Os(ppb)(bpy) 2] 2+ and [Os(L)(bpy) 2] 2+ have been synthesised and their electrochemical, electronic absorption and UV–Vis spectrochemical properties measured. Syntheses of the rhenium(I) complexes fac-[Re(L″)(CO) 3Cl] (L″ = [2,3-a:3 ′,2 ′-c]dipyridophenazine, [2,3-a:3 ′,2 ′-c]dipyrido-6,7-dimethylphenazine, [2,3-a:3 ′,2 ′-c]dipyrido-6,7-dichlorophenazine, [2,3-a:3 ′,2 ′-c]dipyrido[1,2-e]benzophenazine) are also reported. The osmium(II) complexes [Os(L ′)(bpy) 2] 2+ (L ′ = 2,3-di-(2-pyridyl)quinoxaline, 6,7-dimethyl-2,3-di-(2-pyridyl)quinoxaline, 6,7-chloro-2,3-di-(2-pyridyl)quinoxaline, 2,3-di-(2-pyridyl)benzo[g]quinoxaline, 4-methyl-di-(2-pyridyl)quinoxaline) have also been prepared and studied. The electronic spectra of the Os and Re complexes are dominated by strong MLCT transitions. The lowest energy MLCT transitions correlate linearly with the first reduction potential for the [Os(L)(bpy) 2] 2+ series. Electrochemical oxidation of the [Os(L)(bpy) 2] 2+ and [Os(L ′)(bpy) 2] 2+ complexes results in the appearance of LMCT transitions in the visible region while reduction of the [Os(L)(bpy) 2] 2+ complexes produces complex electronic spectra. Comparison with the reduced fac-[Re(L″)(CO) 3Cl] complexes allows assignment of L″ − π→π * transitions in the NIR (1200–1000 nm) and red (850–700 nm) regions. The nonsymmetrical ligands [2,3-a:3 ′,2 ′-c:3″,2″-e]tripyridoquinoxaline and [2,3-a:3 ′,2 ′-c]dipyrido-5-methylphenazine both coordinate to the [Os(bpy) 2] 2+ unit in a stereospecific manner to give a single geometric isomer. The crystal structure of [Re(CO) 3(ppb)Cl] is reported, in which the polypyridyl ligand deviates significantly from planarity.

Synthesis of rhenium(I) and technetium(I) carbonyl/dithioether ligand complexes bearing 3,17β-estradiol

Abstract Tricarbonyldithioethermetal(I) complexes of rhenium and technetium with a pendant 3,17β-estradiol have been synthesized and characterized. The steroid ligand was bound to the metal centre by the two sulfur atoms of a 4,7-dithiaoct-1-ine spacer.

Synthesis of Rhenium(V) 2,4,6-Trimethylbenzylidyne Complexes by Abstracting "O2-" from an Acyl with Triflic Anhydride

Synthesis of Rhenium(V) 2,4,6-Trimethylbenzylidyne Complexes by Abstracting "O2-" from an Acyl with Triflic Anhydride

Reductive syntheses of transition metal fluoride compounds. Synthesis of rhenium, osmium, and iridium pentafluorides and tetrafluorides

Reductive syntheses of transition metal fluoride compounds. Synthesis of rhenium, osmium, and iridium pentafluorides and tetrafluorides