The coordination properties of the 1,1'-bis[((6-methyl)-2-pyridyl)amido]ferrocene ligand () towards group 11 and palladium complexes have been studied. coordinates as the bridging ligand, through the pyridinic nitrogen atoms, when reacting with the gold(i) compounds [Au(OTf)(PPh(3))] and [Au(C(6)F(5))(tht)] or with the gold(iii) species [Au(C(6)F(5))(3)(tht)] leading to linear or square planar derivatives, respectively. The reaction of with [O(AuPPh(3))(3)]ClO(4) affords the tetranuclear compound [Au(4)(L-H)(2)(PPh(3))(4)](ClO(4))(2) in which the amide groups have been deprotonated and the ligand acts as dianionic, N,N,N,N-tetradentate. The treatment of the ligand with silver salts leads to mononuclear complexes with the ligand acting as N,N,O or N,N chelating in [AgL]OTf, or [AgL(2)]OTf, or to dinuclear species with an N,N bridging ligand in [Ag(2)(PPh(3))(2)(mu-L)](OTf)(2). Tetracoordination around the copper atom is proposed for the copper complexes [CuL(PPh(3))(2)]PF(6), [CuL]PF(6), or [CuL(2)]PF(6) with the ligand coordinated in an NH,NH,N,N or an N,N chelating fashion. Finally the palladium compound [PtCl(2)L] has been synthesized with a trans-chelating ligand. In the structures of some of these derivatives the presence of secondary interactions such as weak hydrogen bonds of the type C-HO, C-HN or C-HX (X = F, Cl) or even MO interactions leads to supramolecular networks.

Complexes of the ligand Fcterpy (Fcterpy = 4′-ferrocenyl-2,2′:6′,2′-terpyridine) with group 11 metals display different coordination modes. The reaction with complexes [Cu(NO3)(PPh3)2] or [M(OTf)(PR3)] (OTf = trifluoromethyl sulphonate) gives the species [M(Fcterpy)(PR3)]X (M = Cu, X = PF6, PR3 = PPh3(1); M = Ag, X = OTf, PR3 = PPh3(2), PPh2Me (3); M = Au, X = OTf, PR3 = PPh3(4)) in which the ligand is coordinated as a tridentate chelate to the metal. Treatment with [Cu(NCMe)4]PF6or Ag(OTf) in 1:1 molar ratio gives the dinuclear complexes [M2(Fcterpy)2]X2(M = Cu (5), Ag (6)), in which the ligand is tetradentate because the central pyridine group is bonded to two metals. The reaction with the gold(I) complex [Au(C6F5)(tht)] (tht = tetrahydrothiophene) leads to the first example of a terpyridine ligand bonded to three metal atoms, [Au3(C6F5)3(Fcterpy)] (7); in the product of the corresponding reaction with the gold(III) derivative [Au(C6F5)3(OEt2)] to give [Au(C6F5)3(Fcterpy)] (8), the ligand is monodentate, which is also unusual for a terpyridine ligand.Key words: copper, silver, gold, terpyridine, ferrocene derivatives

The ligand 1,1-bis[N,N′-(2-diphenylphosphino) amide]ferrocene, Fc(CONHCH 2 CH 2 PPh 2 ) 2 (L), has been synthesized by reaction of the chloro carbonyl derivative Fc(COCl) 2 and the aminophosphine NH 2 CH 2 CH 2 PPh 2 . The coordination properties towards silver(I), gold(I) and gold(III) compounds have been explored. Several complexes with the diphosphine acting as bidentate chelating or bridgind ligand have been prepared. Furthermore the dinuclear species [Au 2 Fc(CONCH 2 CH 2 PPh 2 ) 2 ] with the ligand coordinated through the phosphorus and the deprotonated amido group have been achieved.

The ligands {[bis(2-pyridyl)amino]carbonyl}ferrocene (L1) and 1,1'-bis {[bis(2-pyridyl)amino]carbonyl}ferrocene (L2) have been prepared by treatment of the mono- or 1,1'bis(chlorocarbonyl)ferrocene derivatives with dipyridylamine in a 1:1 or 1:2 ratio, respectively. The ligand properties of these compounds towards group 11 and palladium complexes have been studied. Ligand L1 coordinates to these compounds to give four-coordinate [Cu(L1)(2)](+), [PdCl2(L1)] and [Ag(OTf)(L1)(PR3)] or three-coordinate [Ag(OTf)(L1)] and [Au(C6F5)(L1)] compounds. The ligand coordinates in a chelate fashion in all cases. The reactivity of L2 is somewhat different because coordination to copper or silver atoms can take place through several pyridine units either from different cyclopentadienido rings, as in [Cu(L2)](+), [Ag-2(OTf)(2)-(L2)] and [Ag(OTf)(L2)(PPh3)], or from the same cyclopentadienido ring, as in [Ag-2(OTf)(2)(L2)(PPh3)], Coordination as a bridging ligand for four gold atoms has also been achieved in [Au-4(C6F5)(4)(L2)] and [Au-4(L2)(PPh3)4](OTf)(4). The ligands and some complexes have been characterized by Xray diffraction studies and show the presence of several hydrogen bonds that lead to supramolecular structures. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008).

The ligands {[bis(2-pyridyl)amino]carbonyl}ferrocene (L1) and 1,1′-bis{[bis(2-pyridyl)amino]carbonyl}ferrocene (L2) have been prepared by treatment of the mono- or 1,1′-bis(chlorocarbonyl)ferrocene derivatives with dipyridylamine in a 1:1 or 1:2 ratio, respectively. The ligand properties of these compounds towards group 11 and palladium complexes have been studied. Ligand L1 coordinates to these compounds to give four-coordinate [Cu(L1)2]+, [PdCl2(L1)] and [Ag(OTf)(L1)(PR3)] or three-coordinate [Ag(OTf)(L1)] and [Au(C6F5)(L1)] compounds. The ligand coordinates in a chelate fashion in all cases. The reactivity of L2 is somewhat different because coordination to copper or silver atoms can take place through several pyridine units either from different cyclopentadienido rings, as in [Cu(L2)]+, [Ag2(OTf)2(L2)] and [Ag(OTf)(L2)(PPh3)], or from the same cyclopentadienido ring, as in [Ag2(OTf)2(L2)(PPh3)2]. Coordination as a bridging ligand for four gold atoms has also been achieved in [Au4(C6F5)4(L2)] and [Au4(L2)(PPh3)4](OTf)4. The ligands and some complexes have been characterized by X-ray diffraction studies and show the presence of several hydrogen bonds that lead to supramolecular structures.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

Silver salts are used as promoters for the cyclization to novel ferrocene-containing indolizine systems in only one step and with the simultaneous activation of the 7-position of the heterocyclic ring. The reaction of 2-[3-(ferrocenyl)-1-oxoprop-2-enyl]pyridine with [Ag(OTf)(PR3)] (OTf = trifluoro-methylsulfonate; PR3 = PPh3, PPh2Me) occurs with the precipitation of metallic silver and formation of the indolizine system. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

The gold(I) complex [Au-3(C6F5)(3)(eta(3)-Fcterpy)] (Fcterpy = 4'-ferrocenyl-2,2':6',2"-terpyridine) represents the first example of a terpyridine ligand bonded to three different metals. The aurophilic interactions present in the molecule may contribute to the overall stability of the system, as was shown by DFT calculations. The positive Mayer indices (0.152 and 0.138), as well as the magnitude of the binding interaction between terpy and the Au(I)L fragments, support this interpretation.

The reaction of the unsymmetrical ligands 1-diphenylphosphino-1'-(phenylsulfanyl) ferrocene and 1-diphenylphosphino-1'-(phenylselenyl) ferrocene, Fc(EPh) PPh2 (E = S, Se), with several group 11 metal derivatives leads to the synthesis of complexes of the type [MX{Fc(EPh) PPh2}] (M = Au, X = Cl, C6F5; M = Ag, X = OTf), ( OTf = trifluoromethanesulfonate), [M{Fc(EPh) PPh2}(2)] X ( M = Au, X = ClO4; M = Ag, X = OTf), [M(PPh3){Fc( EPh) PPh2}] OTf (M = Au, Ag), [Au-2{Fc(SPh) PPh2}(2)](ClO4)(2), [Au(C6F5)(2){Fc(SePh) PPh2}] ClO4, [Au(C6F5)(3){Fc(EPh) PPh2}], [Au-2(C6F5)(6){Fc(SePh) PPh2}] or [Cu{Fc(EPh) PPh2}(2)] PF6 ( E = S, Se). In these complexes coordination depends upon the metal centre; with gold it takes place predominantly to the phosphorus atom and with silver and copper to both phosphorus and chalcogen atoms. The treatment of some of the gold complexes with other metal centres affords heterometallic derivatives that in some cases are in equilibrium with the homometallic derivatives. Several compounds have been characterized by X-ray diffraction, four pairs of homologous compounds, yet not a single pair is isotypic. In many of them a three dimensional network is formed through secondary bonds such as hydrogen bonds, Au center dot center dot center dot Cl or Au center dot center dot center dot Se interactions. The complex [ Ag( OTf){Fc( SePh) PPh2}] forms one-dimensional chains through trifluoromethanesulfonate bridging ligands.

4',4"'-Bis(ferrocenyl)-2,2':6',2'':6",2'":6'",2-''"-quinquepyridine(Fc(2)qpy)reacts with AgOTf (OTf = trifluoromethylsulfonate) to give a complex of stoichiometry [Ag(Fc2qpy)]OTf. The crystal structure reveals a dinuclear arrangement among the cations with an (AgAg)-Ag-... close contact of 3.089(2) A. The ligands are wrapped around the silver atoms in a double helical array. Further hydrogen bonding between triflate units and the protons of the ferrocene or pyridine moieties results in a supramolecular structure. Theoretical studies confirm the existence of a weak Ag-Ag bond, and show that the dinuclear form can be more stable than the mononuclear one, when there is a favorable balance between the reorganization energy of the two quinquepyridine chains and the energy released by the formation of stronger Ag-N bonds and the new Ag-Ag interaction in the helix, ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004).