Search results for "Rhodium"
showing 10 items of 244 documents
Five coordinate complexes of the type Rh(SnCl3)(NBD)L2
1983
Several new rhodium complexes of general formulation Rh(SnCl3)(NBD)L2 (L=P(OMe)3, P(OMe)2Ph, P(OMe)Ph2, P(OEt)3, P(OEt)2Ph, P(OEt)Ph2, P(O-i-Pr)3, P(OPh)3) have been prepared and characterized by elemental analysis and by i.r. and n.m.r. spectroscopy. The complexes show low or no conductivity in acetone solution and react with carbon monoxide (1 atm).
Synthesis and Complexation of the Metalloligand {(η5-C5H5)[η5-C5Me3-1,2-(PPh2)2]TiCl2} (TiPHOS): The First Example of a 1,2-Bis(diphenylphosphanyl)ti…
2001
The reaction of lithium 1,2-bis(diphenylphosphanyl)trimethylcyclopentadienide (1) with CpTiCl3 leads to the formation of the titanocene diphosphane {(η5-C5H5)[η5-C5Me3-1,2-(PPh2)2]TiCl2} (TiPHOS, 2). This metalloligand reacts readily with (NBD)Cr(CO)4 and W(CO)5(THF) to give, in both cases, the bimetallic chelate complexes (TiPHOS)Cr(CO)4 (3) and (TiPHOS)W(CO)4 (4). The structure of 4 has been determined by X-ray diffraction. The synthesis of a new early-late heterobimetallic complex (TiPHOS)Rh(CO)Cl (5) is reported.
Neutral one-dimensional metal chains consisting of alternating anionic and cationic rhodium complexes.
2012
The metallophilic interactions were investigated within chains of oppositely charged rhodium carbonyl complexes. The cationic [Rh(CO)(2)(L)](+) (L = 2,2'-bipyridine and 1,10-phenanthroline) and anionic [RhCl(2)(CO)(2)](-) units were self-assembled into one dimensional rhodium chains supported by electrostatic interactions. The array of Rh centers in {[Rh(CO)(2)(2,2'-bpy)][RhCl(2)(CO)(2)]}(n) was found to be nearly linear with a Rh···Rh···Rh angle of 170.927(11)° and Rh···Rh distances of 3.3174(5) Å and 3.4116(5) Å. The crystal structure of {[Rh(CO)(2)(1,10-phen)][RhCl(2)(CO)(2)]} consisted of two sets of crystallographically independent chains with slightly different Rh···Rh···Rh angles (17…
Density functional theory based screening of ternary alkali-transition metal borohydrides: a computational material design project.
2009
We present a computational screening study of ternary metal borohydrides for reversible hydrogen storage based on density functional theory. We investigate the stability and decomposition of alloys containing 1 alkali metal atom, Li, Na, or K M1; and 1 alkali, alkaline earth or 3d / 4d transition metal atom M2 plus two to five BH4 groups, i.e., M1M2BH42‐5, using a number of model structures with trigonal, tetrahedral, octahedral, and free coordination of the metal borohydride complexes. Of the over 700 investigated structures, about 20 were predicted to form potentially stable alloys with promising decomposition energies. The M1Al/ Mn/ FeBH44, Li/ NaZnBH43, and Na/ KNi/ CoBH43 alloys are …
Fluorescent organometallic rhodium(I) and ruthenium(II) metallodrugs with 4-ethylthio-1,8-naphthalimide ligands: Antiproliferative effects, cellular …
2018
Fluorescent 4-ethylthio-1,8-naphthalimides containing rhodium(I) N-heterocyclic carbene (NHC) and ruthenium (II) NHC fragments were synthesised and evaluated for their antiproliferative effects, cellular uptake and DNA-binding activity. Both types of organometallics triggered ligand dependent efficient cytotoxic effects against tumor cells with the rhodium(I) NHC derivatives causing stronger effects than the ruthenium (II) NHC analogues. Antiproliferative effects could also be observed against several pathogenic Gram-positive bacterial strains, whereas the growth of Gram-negative bacteria was not substantially affected. Cellular uptake was confirmed by atomic absorption spectroscopy as well…
Halogenido ligand exchange synthesis, spectroscopic properties and thermal behaviour of the inorganic–organic hydrogen-bonded network solid [4,4′-H2b…
2014
Abstract Dark-red single crystals of 4,4′-bipyridinium triaquahydrogen(1+) hexabromidorhodate(III) [4,4′-H2bipy][H7O3][RhBr6] (1) have been synthesized by a diffusion-controlled ligand exchange process from rhodium(III) chloride trihydrate and 4,4′-bipyridine dissolved in hydrochloric and hydrobromic acid, respectively. 1 could be considered as an inorganic–organic hydrogen-bonded network solid built up from the inorganic isolated hexabromidorhodate [RhBr6]3− octahedra, organic 4,4′-bipyridinium(2+) [4,4′-H2bipy]2+ and triaquahydrogen(1+) [H7O3]+ cations with nearly symmetrical O⋯O distances. The oppositely charged components in the structure of 1 are bound together by an intricate system o…
Carbene complexes of rhodium and iridium from tripodal N-heterocyclic carbene ligands: synthesis and catalytic properties.
2004
Two tripodal trisimidazolium ligand precursors have been tested in the synthesis of new N-heterocyclic carbene rhodium and iridium complexes. [Tris(3-methylbenzimidazolium-1-yl)]methane sulfate gave products with coordination of the decomposed precursor. [1,1,1-Tris(3-butylimidazolium-1-yl)methyl]ethane trichloride (TIMEH(3)(Bu)) coordinated to the metal in a chelate and bridged-chelate form, depending on the reaction conditions. The crystal structures of two of the products are described. The compounds resulting from the coordination with TIME(Bu) were tested in the catalytic hydrosilylation of terminal alkynes.
First Dibenzophospholyl(diphenylphosphino)methane−Borane Hybrid P−(η2-BH3) Ligand: Synthesis and Rhodium(I) Complex
2009
The first dibenzophospholyl(diphenylphosphino)methane−borane hybrid ligand has been prepared from a Pd-catalyzed reaction of (chloromethyl)diphenylphosphine−borane with the dibenzophospholyl anion. This borane precursor is readily synthesized using a promising new reaction of diphenylphosphine−borane with dichloromethane, under phase transfer catalysis (PTC) conditions. The dibenzophospholyl(diphenylphosphino)methane−borane acts as a chelating P−(η2-BH3) ligand to afford an air-stable Rh(I) complex. The X-ray crystal structure of this complex shows complexation of both benzophospholyl and borane moieties.
Synthesis of new orthometallated iridium(III) compounds by chemical and electrochemical methods
1987
Abstract Replacement of one phosphine ligand in IrCl 3 (η 2 -PCBr)(η 1 -PCBr) ( 1 ) (PCBr = P( o -BrC 6 F 4 )Ph 2 ), by various P-donor ligands has given compounds of stoichiometry IrCl 3 (η 2 -PCBr)L ( 3 : L = PMePh 2 ; 4 : L = P( p -MeC 6 H 4 ) 3 ; 5 : L = P(OMe) 3 , 6 : L = P(OPh) 3 ). All of these show two irreversible reduction peaks in the range −1.1, −1.3 and ca. −2.0 V. The electrochemical reduction of compound 1 at −1.5 V (at 0°C) leads to a very reactive iridium(I) species, probably IrCl(PCBr) 2 , which undergoes intramolecular orthometallation at room temperature. Three compounds are obtained as the results of this chemical conversion: IrBr 2 (PC)(PCBr) ( 7 ), IrCl 2 (PC)(PCBr) (…
Reaction of Rh2(μ2-O2CCH3)3[μ2-(C6H4)PMePh](HO2CCH3)2 with triphenylphosphine: rearrangement of the metalated PMePh2 ligand and formation of a compou…
1995
The reaction of [Rh2(μ2-O2CCH3)3{μ2-(C6H4)PMePh}] (1) in CHCl3 with one mole of PPh3 gives the two phosphine monoadducts, which are in rapid equilibrium above −40 °C. After 6 h at room temperature this mixture gives [Rh2(μ2-O2CCH32{μ2-(C6H4)PMePh}{μ2-(C6H4)PPh2}](HO2CCH3)2 (3), a doubly metalated compound with a head-to-head configuration. 1 reacts with two moles of PPh3, forming the bis-adduct 1.P2, which at 10 °C gives a mixture 3, in the form of its phosphine adduct 3.P, and [Rh2(μ2-O2CCH3)2{μ2-(CH2)PPh2}{μ2- (C6H4) PPh2}(PPh3)] (2). It is confirmed that 3.P is not the kinetic product in the reaction from 1.P2 to 2. The structure of [Rh2(μ2-O2CCH3)2{μ2-(CH2)PPh2}{μ2-(CP6H4) PPh2} (PPh3)]…