14911-01-4Relevant academic research and scientific papers
Spectroscopic, DFT analysis, antimicrobial and cytotoxicity studies of three gold(III) complexes
Ramadan, Ramadan M.,Noureldeen, Amani F. H.,Abo-Aly, Mohamed M.,El-Medani, Samir M.
, p. 213 - 225 (2022)
Three gold(III) complexes were synthesized using 2-pyrazinecarboxamide, pyridine or bipyridine ligand. Complexes were characterized by spectroscopic and analytical techniques (IR, Raman, 1H NMR, mass spectrometry and elemental analysis). Thermogravimetry
Co-ordination Chemistry of Dimethylgold(III). Synthesis, Spectroscopic, and Structural Studies of Complexes With Neutral Aromatic Nitrogen-donor Ligands
Canty, Allan J.,Minchin, Nigel J.,Healy, Peter C.,White, Allan H.
, p. 1795 - 1802 (1982)
Dimethylgold(III) nitrate reacts with neutral ligands to form the complexes NO3*H20 (tpm = tri-2-pyridylmethane) and NO3 .The crystal structures of complexes of tpzm, tpm, and dpt have been determined by single-crystal X-ray diffraction at 295 K and refined by least-squares methods to R = 0.033, 0.029, and 0.042 for 3 043, 1 616, and 2 529 independent ' observed ' reflections, respectively.In these structures the (1+) cations have essentially cis-square-planar co-ordination for gold(III), AuC2N2, with Au-C 2.023(7)-2.041(12) Angstroem and Au-N 2.127(8)-2.142(8) Angstroem.In complexes of the potential tridentate ligands one pyridyl group is not co-ordinated in the tpm complex, and one pyrazolyl group is involved in a weak axial Au...N interaction in the tpzm complex.Comparison of the (1)H n.m.r. spectra of complexes of the potentially tridentate ligands (tpzm, tpm, and tpmo) with model complexes of bidentate ligands (dbzm, dpm, and dpt) suggests that the co-ordination behaviour of the ligands in methanol resambles that found in solid state.Crystal data: NO3, monoclinic, space group P21/n, a = 16.72(1), b = 9.662(3), c = 10.700(4) Angstroem, β = 107.83(3)o, Z = 4; NO3*2H2O, orthorhombic, space group P212121, a = 18.56(1), b = 11,150(7), c = 9.983(7) Angstroem, Z = 4; NO3, monoclinic, P21/n, a = 14.142(6), b = 13.012(7), c = 10.372(3) Angstroem, β = 100.60(3)o, Z = 4.
Reactions of gold(III) complexes with alkenes in aqueous media: Generation of bis-(β-hydroxyalkyl)gold(III) complexes
Rezsnyak, Chad E.,Autschbach, Jochen,Atwood, Jim D.,Moncho, Salvador
, p. 1153 - 1165 (2013/07/28)
Reactions of gold(III) complexes with ethylene and propylene in water provide the first such examples not accompanied by reduction of the gold. HAuC14 and AuCL3(TPPTS) produce organic products (alcohol, aldehyde/ketone, etc.) with gold reduction to the metal. However, [Au(bipy)CL2] Cl in water produces the gold(III) β-hydroxy complexes, [Au(bipy)(CH2CH2OH)2]X (X =Cl, PF6) and [Au(bipy)(CH2CH(OH)CH3]Cl, which are stable in solution. These complexes could not be isolated, but were characterized by NMR and high-resolution mass spectra. [Au(terpy)Cl]CL2 fails to react with ethylene in water, even at elevated temperatures. DFT computations were performed to investigate the reaction mechanism.
Displacement of neutral nitrogen donors by chloride in AuCl3(am) (am = pyridines and amines): Kinetics and DFT calculations show the effects of basicity and π-acceptor ability
Pitteri, Bruno,Bortoluzzi, Marco
, p. 4456 - 4461 (2008/03/12)
The kinetics of the process AuCl3(am) + Cl- → AuCl4- + am (am = sp2 N-donor isosteric pyridines with different π systems and sp3 amines; they cover a wide range of basicity) have been studied in methanol at 25°C. The reactions obey the usual two-term rate law observed in substitutions on square-planar complexes. The second-order rate constants, k2, are very sensitive to the nature of the leaving group, and plots of log k2 against the pKa of the conjugate acids are linear, with the same slope, -0.68, for both normal pyridines and pyridines with a more extended π system, such as 4-cyanopyridine, isonicotinic acid, methyl isonicotinate and 4-acetylpyridine. The reactivity of the considered N-donors is different and follows the order sp3 N-donors > normal pyridines > π-extended pyridines. This result, with the support of ground-state DFT calculations on the AuCl3(am) derivatives, is explained on the basis of an Au-N bond enforcement due to an increased π-back-donation contribution. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
Equilibria of the Substitution of Pyridine, 2,2′-Bipyridyl, and 1,10-Phenanthroline for Cl- in AuCl-4 in Aqueous Solution
Mironov,Tsvelodub
, p. 143 - 148 (2008/10/08)
Equilibria of AuCl-4 + HL+ = AuLCl3-ii + H+ + (4 - i)Cl- substitutions for L = pyridine (py, i = 3), 2,2′-bipyridyl (bipy, i = 2), or 1,10-phenanthroline (phen, i = 2) are studied spectrophotometrically at 25°C and I = 1 mol/l in acid aqueous solution. The equilibrium constants are determined to be logβ*1 = -2.13 ± 0.05 for py, 3.6 ± 0.1 for bipy, and 4.3 ± 0.1 for phen. With reference to the protonation constants of the amines, the equilibrium constants for AuCl-4 + L = AuLCl3-ii + (4 - i)Cl- are logβ1 = 3.3 for py, 8.2 for bipy, and 9.5 for phen. No aqueous complex species other than those specified above are found. The possibility of the formation of complexes in which the bidentate ligand is coordinated to the central atom through one donor atom is addressed.
Sulfur-containing gold(III) chelates and their use in heterovalent dimer synthesis: Crystal structures of AuIII[CH2P(S)Ph2]2Br, [AuIII[S2P(OH)Ph]2]Cl, and AuIII[CH2P(S)Ph2][S2CN(Et) 2]2
Murray,Garzón, Guillermo,Raptis, Raphael G.,Mazany, Anthony M.,Porter, Leigh C.,Fackler Jr., John P.
, p. 836 - 842 (2008/10/08)
The oxidation of [PPN][Au(CH2P(S)Ph2)2] with Br2 in CH2Cl2 gives the neutral AuIII complex Au[CH2P(S)Ph2]2Br (Au-(MTP)2Br), containing one chelating and one dangling [CH2P(S)Ph2]- (MTP) ligand. The sulfur atom of the chelating MTP ligand is trans to the Br. From 1H NMR studies, the complex in solution is undergoing a dynamic rearrangement on the NMR time scale that exchanges the methylene resonances. The reaction of Au(MTP)2Cl with Au(THT)Cl gives a 2:1 ratio of the heterovalent AuI/AuIII complex Cs-[AuIAuIIIHMTP)2Cl2] and the homovalent AuII-AuII complex Ci-[Au(MTP)Cl]2. The reaction of Au(THT)Cl with NaS2P(OR)Ph, R = Et and H, in THF gives [Au[S2P(OR)Ph]2]Cl. The AuIII complex with R = OH has been characterized crystallographically; in the solid state both the cis and trans isomers are observed. In solution, via 1H NMR spectroscopy, cis and trans interconversion is facile. The reaction of tetraethylthiuram disulfide with [Au(MTP)]2 cleaves the dimer giving Au(MTP)(S2CN(Et)2)2, a single-center, two-electron-oxidation product, rather than a two-center, two-electron-oxidation product. In this complex the MTP is a dangling ligand, carbon bound to the metal atom. One diethyldithiocarbamate ligand is also dangling with the other chelating. Crystal data for Au(MTP)2Br: P1 (No. 2), a = 11.672 (4) ?, b = 12.814 (3) ?, c = 10.143 (4) ?, α = 109.26 (3)°, β = 110.65 (3)°, γ = 71.98 (2)°, V = 1307.7 (7) ?3, Z = 2, R = 0.0700, Rw = 0.0732 for 1738 reflections with I > 3σ(I) and 238 parameters. Crystal data for [Au[S2P(OH)Ph]2]Cl: C2/c (No. 15), a = 23.736 (12) ?, b = 13.807 (6) ?, c = 20.555 (7) ?, β = 104.25 (3)°, V = 6558 (5) ?3, Z = 12, R = 0.0569, Rw = 0.0612 for 190 parameters with 2551 reflections with i > 3σ(i). Crystal data for Au(MTP)(DTC)2: P1 (No. 2), a = 11.820 (1) ?, b = 14.462 (2) ?, c = 10.167 (2) ?, α = 104.41 (1)°, β = 110.90(2)°, γ = 102.61 (2)°, V = 1479.2 (6) ?3, Z = 2, R = 0.038, Rw = 0.049 for 3743 reflections with I > 3σ(I) and 289 parameters.
