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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(N[O.sub.3])[(P[Ph.sub.3]).sub.2]] or [M(OTf)(P[R.sub.3])] (OTf = trifluoromethyl-sulphonate) gives the species [M(Fcterpy)(P[R.sub.3])]X (M = Cu, X = P[F.sub.6], P[R.sub.3] = P[Ph.sub.3] (1); M = Ag, X = OTf, P[R.sub.3] = P[Ph.sub.3] (2), P[Ph.sub.2]Me (3); M = Au, X = OTf, P[R.sub.3] = P[Ph.sub.3] (4)) in which the ligand is coordinated as a tridentate chelate to the metal. Treatment with [Cu[(NCME).sub.4]]P[F.sub.6] or Ag(OTf) in 1:1 molar ratio gives the dinuclear complexes [[M.sub.2][(Fcterpy).sub.2]][X.sub.2] (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([C.sub.6][F.sub.5])(tht)] (tht = tetrahydrothiophene) leads to the first example of a terpyridine ligand bonded to three metal atoms, [[Au.sub.3][([C.sub.6][F.sub.5]).sub.3](Fcterpy)] (7); in the product of the corresponding reaction with the gold(III) derivative [Au[([C.sub.6][F.sub.5]).sub.3](OEt2)] to give [Au[([C.sub.6][F.sub.5]).sub.3](Fcterpy)] (8), the ligand is monodentate, which is also unusual for a terpyridine ligand. Key words: copper, silver, gold, terpyridine, ferrocene derivatives Les complexes du ligand Fcterpy [Fcterpy = 4'-ferrocenyl-2,2':6',2'-terpyridine] avec les metaux du groupe 11 presentent divers modes de coordination. Les reactions avec des complexes [Cu(N[O.sub.3])[(P[P.sub.3]).sub.2]] ou [M(OTf)(P[R.sub.3])] (Otf = trifluoromethylsulfonate) conduisent a des especes [M(Fcterpy)(P[R.sub.3])]X [M = Cu; X = P[F.sub.6]; P[R.sub.3] = P[Ph.sub.3] (1); M = Ag; X = OTf; P[R.sub.3] = P[Ph.sub.3] (2); P[Ph.sub.2]R (3); M = Au; X = OTf; P[R.sub.3] = P[Ph.sub.3] (4)] dans lesquels le ligand est coordine au metal sous la forme de chelate tridentate. Le traitement avec du [Cu[(NCME).sub.4]]P[F.sub.6] ou du Ag(OTf), dans un rapport molaire de 1:1, conduit a la formation de complexes binucleaires [[Me.sup.2][(Fcterpy).sub.2]][X.sub.2] (M = Cu (5); Ag (6)] dans lesquels le ligand est tetradentate parce que le groupe pyridine central est lie a deux metaux. La reaction avec le complexe d'or(I) [Au([C.sub.6][F.sub.5])(tht)] (tht = tetrahydrothiophene) conduit au premier exemple d'un ligand terpyridine lie a trois atomes metalliques, [[Au.sub.3][([C.sub.6][F.sub.5]).sub.3](Fcterpy)] (7); dans le produit de la reaction correspondante avec le derive d'or(III) [Au[([C.sub.6][F.sub.5]).sub.3](O[Et.sub.2])] conduisant a la formation de [Au[([C.sub.6][F.sub.5]).sub.3]Fcterpy)] (8), le ligand est sous la forme monodentate qui est inhabituelle pour un ligand terpyridine. Mots-cles : cuivre, argent, or, terpyridine, derives du ferrocene. [Traduit par la Redaction], Introduction The coordination chemistry of terpyridine ligands with various metals has been the subject of numerous studies, inspired by the exciting photophysical properties of metal-- polypyridyl complexes (1). In these [...]

The high-yield synthesis of gold-tellurollate clusters [[Au.sub.8]([mu]-TeR).sub.8][[(PR'.sub.3]).sub.4]] (TeR = TePh, TeTol, [PR'.sub.3] = P[Ph.sub.3], P[Ph.sub.3]py) is described. The gold-tellurium complexes are novel due to their special structural features and luminescent behavior in solid state and in solution.

Substitution of the arsine ligands in [Au(sub 4){(PPh2)(sub 2)C2B9H10}(sub 2)(AsPh3)(sub 2)] by tertiary phosphines leads to the new cluster compounds [Au(sub 4){(PPh2)(sub 2)C2B9H10}(sub 2)(PR3)(sub 2)]. MP2 calculations indicate that the two types of chemically nonequivalent gold atoms are assigned as Au(I) and Au(O), the role of correlation in the gold-gold interactions are emphasized and the compounds are found by luminescent.

A new study investigates the optical properties of [Au2Ag2(C6F5)4(OCMe2)]n at room temperature and in an acetone solution.

Research has been conducted on linear ferrocenyl phosphine gold(I) and silver(I) complexes. The use of X-ray diffraction in determining the crystal structure of the complexes is discussed.

The ligand FcCHN(CH2)2SH (Fc = (eta(super 5)-C5H5)Fe(eta(super 5)-C5H4)) was prepared from the condensation reaction of ferrocenecarbaldehyde with beta-mercaptoethylamine. The ligand is easily oxidized to the disulfide derivative FcCHN(CH2)2S2(CH2)2NCHFc. Coordination of the gold centers occurs through the sulfur or nitrogen atoms. The crystal structure of (FcCHN(AuPPh3)(CH2)2S(AuPPh3)2)(TfO)2 revealed coordination of one gold(phosphine) fragment to the nitrogen and two fragments to the sulfur atom, as well as short gold-gold interactions.

A study is conducted on the first heterobimetallic gold(I) complexes with the tetrathiovanadate anion. It is shown that the reaction of (NH4)3VS4 with (AuCl(PR3)) in dichloromethane yields a dark red solution where the complexes (VS4(AuPR3)3) (PR3 = PPh3, PPh2Me, PEt3, PMe3, P(M-Tol)3 and P(p-Tol)3) can be isolated. The crystal structure of (VS4(AuPPh3)2(Au(PPh3)2)) is also isostructural with the related copper derivative.

The substitution of the chlorine ligand to give [Au2X2(mu-dppf)] (X = Br, I) results from the reaction of [Au2Cl2(mu-dppf)] (dppf = 1,1'-bis(diphenylphosphino)ferrocene) with KX in acetone. The 31P{1H] NMR spectra indicate a singlet for the equivalent phosphorous atoms. Three multiplets with an intensity ratio 1:1:5 appear in the 1H NMR spectra. The crystal structure of [Au3(mu-3-Spy)(mu-dppf)(PPh2Me)](OTf)2 is the first example where a pyridinethiolate ligand bridges three gold atoms.

A series of di- and tetranuclear heterobimetallic complexes with unsupported tin-gold bonds were synthesized by the reaction of tris(amido)stannate [MeSi{Me2SiN(p-tol)}3SnLi(Et2O)] with a neutral or anionic gold (I). The synthetic process was characterized by the formation of gold (II) derivatives from a series of reactions involving gold(I), -(II) or -(III) complexes. The resulting compounds also exhibited linear Sn-Au-Au-Sn arrangement with novel tin-gold(II) bonds.

A number of three-coordinate and four-coordinate gold complexes can be found in the oxidation state +1, with these compounds exhibiting dynamic behaviour in solution. Several three- or four-coordinate thiolate or phosphine complexes can be used to treat cancer and rheumatoid arthritis, while three-coordinate complexes are usually luminescent and can act as photocatalysts. Some three-coordinate complexes do not have ligands or phosphine, although the majority are cationic or neutral derivatives with between one and three phosphines. Phosphine is also not found in some four-coordinate gold(I) complexes, although most usually have a metal centre which is bound to between one and four phosphines.

The crystal structure of gold(I) complexes which were synthesized by the treatment of 1,2-dimercapto-o-carborane ligand with two equivalents of (AuClL) in the presence of Na2CO3 were elucidated using Siemens R3 or Stoe STADI-4 diffractometer. Among those examined, three complexes, (Au2(mu-S2C2B10H10)(PPh3)2), (Au2(mu-S2C2B10H10)(mu-((PPh2)2(CH=CH)))) and (Au2(mu-S2C2B10H10)(mu-((PPh2)2(C6H4)))), were found to have short gold-gold interactions.

The sulphur atom in the complex (S(Au2dppf)) can give trinuclear neutral (S(Au(C6F5))(Au2dppf)) or cationic derivatives (S(AuL)-(Au2dppf))ClO4 by coordinating neutral or cationic gold(I) fragments. The dppf in the compound is 1,1'-bis(diphenylphosphino)ferrocene and L is CH2PPh3, PPh3 or PPh2Me. Tri- and tetranuclear complex formation also occurs and they show short gold(I)-gold(I) interactions. The (S(AuL)4) monomer structure may be affected by the ligand attached to Au. Crystallographic data of the complexes obtained from nuclear magnetic resonance spectra analysis are given.

The AuCl(Pr3) reacted with 1,2-(Ph2P)2-1,2-C2B10H10 and yielded Au (PPh2)2C2B9H10 (PPh3) as one of its products. The product was protonated upon addition of NaH while further reaction with Au(PPh3)(tht) ClO4 resulted to the first metallocarborane compound Au2 (PPh2)2C2B9H9 (PPh3)2. The reaction of Au2Cl2(mu-P-P) with 1,2-(Ph2P)2-1,2-C2B10H10, on the other hand, yielded Au2 (PPh2)2C2B9H10 (sub 2) (mu-P-P) P-P=dppe=1,2-bis(diphenylphosphino)ethane, dppp=1,3-bis(diphenylphosphino)propane.

Syntheses of mixed four-coordinate gold(I) complexes with diphosphines or diphosphine sulfides as ligands involve a simple addition reaction between a three-coordinate complex and the corresponding ligands. In solution these complexes show significant kinetic and thermodynamic stabilities. X-ray studies of (Au((PPh2)2C2B10H10)((SPPh2)2CH2))ClO4.CH2CL2 reveal the tetrahdedral geometry of the gold atom with two P and two S atoms.

The reaction of (AuCl(AsPh3)) with dianionic sulfur ligands such as 1,2-benzenedithiolate, 1,3-benzenethiolate and 3,4-toluenedithiolate yields (Au(S-S)(AsPh3)(n)) (S-S is a ligand) complexes. The reaction between equimolar amounts of (Au2(S-S)(PPh)3)2 and (Au(PPh3)(acetone))ClO4 yields trinuclear complexes. This reaction also produces Au(I)/Au(III) complexes as by products. X-ray crystallographic studies help determine the structures of the complexes.

An analysis of the coordination of ferrocenylphosphine as a bridging or chelating ligand in two-, three-, or four-coordinated gold (I) complexes or in gold(III) derivatives, followed the preparation of gold(I) and gold(III) complexes with 1,1'-bis(diphenylphosphino)ferrocene ligand. Formation of a complex which includes bridging and chelating coordination modes and free dppf effects the dimerization of the four coordinated complex.

An easy microscale synthesis can be used to teach chemistry students how a small change of ligands in a complex can determine the NMR spectrum pattern. Interest in application of such complexes in synthesis of tumor-seeking drugs for boron neutron capture therapy and in preparing ceramics and polymers has led to use of two o-carborane derivatives.

An unprecedented reactivity of the ferrocenyl Lawesson reagent, FcP(S)[S.sub.2]P(S)Fc (Fc = ([[eta].sup.5]-[C.sub.5][H.sub.5])Fe([[eta.sup.5]-[C.sub.5][H.sub.4])) with gold and palladium complexes to form phosphonodithioate ligands is reported. The gold complex [[Au.sub.2][{[S.sub.2]P(OH)Fc}.sub.2]] crystallizes with a molecule of [N[(P[Ph.sub.3]).sub.2]]Cl and acts as anion receptor toward the chloride atom to form strong hydrogen bonds between the chloro ligand and the hydroxy groups.

Research has been conducted on nido-diphosphine anions. The authors report that these anions possess luminescence properties.

The study reports a new series if is structural, brilliantly luminescent gold-silver complexes having a group of -16 (Mu)3-bridging atom in which the emission energy changes strikingly from blue to yellow to orange going from O to S to Se. This is the first report of luminescence from a gold(I) oxo system that shows multiple emitting states exist for these compounds.