188422-36-8Relevant articles and documents
Coordination chemistry of gold catalysts in solution: A detailed NMR study
Zhdanko, Alexander,Stroebele, Markus,Maier, Martin E.
, p. 14732 - 14744 (2013/01/15)
Coordination chemistry of gold catalysts bearing eight different ligands [L=PPh3, JohnPhos (L2), Xphos (L3), DTBP, IMes, IPr, dppf, S-tolBINAP (L8)] has been studied by NMR spectroscopy in solution at room temperature. Cationic or neutral mononuclear complexes LAuX (L=L2, L3, IMes, IPr; X=charged or neutral ligand) underwent simple ligand exchange without giving any higher coordinate complexes. For L2AuX the following ligand strength series was determined: MeOHahex-3-yne -aMe 2S3CO2 -≈DMAP3-≈Cl -. Some heteroligand complexes DTBPAuX exist in solution in equilibrium with the corresponding symmetrical species. Binuclear complexes dppf(AuOTf)2 and S-tolBINAP(AuOTf)2 showed different behavior in exchange reactions with ligands depending on the ligand strength. Thus, PPh3 causes abstraction of one gold atom to give mononuclear complexes LLAuPPh3+ and (Ph3P) nAu+, but other N and S ligands give ordinary dicationic species LL(AuNu)22+. In reactions with different bases, LAu+ provided new oxonium ions whose chemistry was also studied: (DTBPAu)3O+, (L2Au)2OH+, (L2Au) 3O+, (L3Au)2OH+, and (IMesAu) 2OH+. Ultimately, formation of gold hydroxide LAuOH (L=L2, L3, IMes) was studied. Ligand- or base-assisted interconversions between (L2Au)2OH+, (L2Au)3O+, and L2AuOH are described. Reactions of dppf(AuOTf)2 and S-tolBINAP(AuOTf) 2 with bases provided more interesting oxonium ions, whose molecular composition was found to be [dppf(Au)2]3O2 2+, L8(Au)2OH+, and [L8(Au)2] 3O22+, but their exact structure was not established. Several reactions between different oxonium species were conducted to observe mixed heteroligand oxonium species. Reaction of L2AuNCMe+ with S2- was studied; several new complexes with sulfide are described. For many reversible reactions the corresponding equilibrium constants were determined. Copyright
Gold(I) Complexes with N-Donor Ligands. 2.1 Reactions of Ammonium Salts with [Au(acac-κC2)(PR3)] to Give [Au(NH3)L]+,[(AuL)2(μ2-NH 2)]+,[(AuL)4(μ4-N)]+, or [(AuL)3(μ3-O)]+. A New and Facile Synthesis of
Vicente, José,Chicote, María-Teresa,Guerrero, Rita,Jones, Peter G.,De Arellano, M. Carmen Ramírez
, p. 4438 - 4443 (2008/10/09)
The complexes [Au(acac-κC2)(PR3)] (acac = acetylacetonate, R = Ph, C6H4OMe-4) react with (NH4)ClO4 to give amminegold(I), [Au(NH3)(PR3)]ClO4, amidogold(I), [(AuPR3)2(μ2-NH2)]ClO 4, or nitridogold(I), [(AuPR3)4(μ4-N)]ClO4, complexes, depending on the reaction conditions. Similarly, [Au(acac-κC2)(PPh3)] reacts with (NH3R')OTf (OTf = CF3SO3) (1:1) or with [H3N(CH2)2NH2]OTf (1:1) to give (amine)gold(I) complexes [Au(NH2R')(PPh3)]OTf (R' = Me, C6H4NO2-4) or [(AuPPh3)2{μ2-H2N(CH 2)2NH2}](OTf)2, respectively. The ammonium salts (NH2R'2)OTf (R' = Et, Ph) react with [Au(acac-κC2)(PR3)] (R = Ph, C6H4OMe-4) (1:2) to give, after hydrolysis, the oxonium salts [(AuPR3)3(μ3-O)]OTf (R = Ph, C6H4OMe-4). When NH3 is bubbled through a solution of [AuCl(tht)] (tht = tetrahydrothiophene), the complex [Au(NH3)2]Cl precipitates. Addition of [Au(NH3)2]Cl to a solution of AgClO4 or TlOTf leads to the isolation of [Au(NH3)2]ClO4 or [Au(NH3)2]OTf, respectively. The crystal structure of [(AuPR3)3(μ3-O)]OTf-Me2CO (R = C6H4OMe-4) has been determined: triclinic, space group P1?, a = 14.884(3) A?, b = 15.828(3) A?, c = 16.061(3) A?, α = 83.39(3)°, β = 86,28(3)°, γ - 65.54(3)°, R1 (wR2) = 0.0370 (0.0788). The [(AuPR3)3(μ3-O)]+ cation shows an essentially trigonal pyramidal array of three gold atoms and one oxygen atom with O-Au-P bond angles of ca. 175° and Au?Au contacts in the range 2.9585(7)-3.0505(14) A?. These cations are linked into centrosymmetric dimers through two short Au?Au [2.9585(7), 3.0919(9) A?] contacts. The gold atoms of the dimer form a six-membered ring with a chair conformation.
