Synthesis of Gold Phosphido Complexes Derived from Bis(secondary) Phosphines. Structure of Tetrameric [Au(MesP(CH₂)₃PMes)Au]₄

Abstract

Treatment of 2 equiv of Au(THT)Cl (THT = tetrahydrothiophene) with the bis(secondary) phosphines HP(R) approximately PH(R) (linker approximately = (CH(2))(3), R = Mes = 2,4,6-Me(3)C(6)H(2) (1), R = Is = 2,4,6-(i-Pr)(3)C(6)H(2) (2), R = Ph (4); approximately = (CH(2))(2), R = Is (3); HP(R) approximately PH(R) = 1,1'-(eta(5)-C(5)H(4)PHPh)(2)Fe (5)), gave the dinuclear complexes (AuCl)(2)(mu-HP(R) approximately PH(R)) (6-10). Dehydrohalogenation with aqueous ammonia gave the phosphido complexes [(Au)(2)(mu-P(R) approximately P(R))](n) (11-15). Ferrocenyl- and phenylphosphido derivatives 15 and 14 were insoluble; the latter was characterized by solid-state (31)P NMR spectroscopy. Isitylphosphido complexes 12 and 13 gave rise to broad, ill-defined NMR spectra. However, mesitylphosphido complex 11 was formed as a single product, which was characterized by multinuclear solution NMR spectroscopy, solid-state (31)P NMR spectroscopy, and elemental analyses. Mass spectrometry suggested that this material contained eight gold atoms (n = 4). A structure proposed on the basis of the (1)H NMR spectra, containing a distorted cube of phosphorus atoms, was confirmed by X-ray crystallographic structure determination. NMR spectroscopy, including measurement of the hydrodynamic radius of 11 by (1)H NMR DOSY, suggested that this structure was maintained in solution. Density functional theory (DFT) structural calculations on 11 were also in good agreement with the solid-state structure.

Gold(I)–Alkynyl Complexes with an N‐Donor Heterocyclic Ligand: Synthesis and Photophysical Properties

“…The geometry of the ligand environment is nearly linear with the N–Au–C≡C bond angles in the 176–178° range. The Au–N and Au–C≡C bond lengths are in agreement with values obtained for analogous gold(I)–alkynyl complexes , …”

Coordination Behaviour of a Hexadentate 1,1′‐Ferrocenylene‐Bridged Bisphosphole towards Coinage Metal Centres

“…This result confirms that the possibility of the free rotation about the “Cp–Fe–Cp” axis in ligand 8 offers a structural diversity to the complex formed from this ligand, which is larger than those associated with the phenylene‐bridged bisphosphole ligand 9 . Apparently, this flexibility is a consequence of the balanced steric situation in 8 , which differs from the situation in diaurated ferrocenylene bisphosphane Fc′(PHPh) 2 for which three diastereomers have been reported on the basis of 31 P NMR spectroscopy 17…”

Late Transition Metal Compounds with 1,1′‐Bis(phosphino)ferrocene Ligands

“…[(AuCl) 2 {1,1′-bis(phenylphosphino)-ferrocene}] undergoes hydrodehalogenation to yield an insoluble product that is formulated as [Au 2 {(C 5 H 4 PPh) 2 Fe}] x . [11] The polymer [AuCl(1)] x can be formed by the addition of 1 to either [(AuCl) 2 (1)] [17] or [AuCl(tetrahydrothiophene)]. [18] 4 ] were also examined.…”

“…The [(AuCl) 2 (PP)] compounds of 1 , 2 , 3 , 4 , 5 , 1,1′‐bis(phenylphosphino)ferrocene, 1,1′‐bis(dimethylaminophosphino)ferrocene, [Fe(C 5 H 4 ‐µ‐PN t Bu) 2 ], and 1,1′‐bis[2,5‐bis(2‐pyridyl)phospholyl]ferrocene have been reported. The oxidative electrochemical behaviors of the 1 , 2 , 3 , 4 , 5 , and 1,1′‐bis(dimethylaminophosphino)ferrocene compounds have been examined, and they exhibited reversible waves, presumably owing to oxidation at the iron center.…”