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The strongly luminescent neutral gold(I) triphosphine complexes [Au(dipnc)(PPh(3))] and [Au(dppnc)(PPh(3))] with dipnc = 7,8-bis(diisopropylphosphino)-nido-carborane ([(PiPr(2))(2)B(9)H(10)C(2))](-)) and dppnc = 7,8-bis(diphenylphosphino)-nido-carborane ([(PPh(2))(2)B(9)H(10)C(2)](-)) are studied in a wide range of temperatures of 1.5

The reaction of [2-(Me(2)NCH(2))C(6)H(4)Se]M (M = Li, K) with the gold(phosphine) complexes [AuCl(PR(3))] gives the mononuclear gold-selenolate species [Au{SeC(6)H(4)(CH(2)NMe(2))-2}(PPh(3))] (1) or [Au{SeC(6)H(4)(CH(2)NMe(2))-2}(PPh(2)py)] (2), respectively. The treatment of the [2-(Me(2)NCH(2))C(6)H(4)Se]M with [Au(2)Cl(2)(mu-P-P)] [P-P = bis(diphenylphosphino)methane (dppm), bis(diphenylphosphino)ethane (dppe), 1,1'-bis(diphenylphosphino)ferrocene (dppf)] derivatives gives complexes with stoichiometry [Au(2){SeC(6)H(4)(CH(2)NMe(2))-2}(2)(mu-P-P)] [P-P = dppm (3), dppe (4), or dppf (5)]. These complexes exhibit a different structural framework, that is, 4 crystallizes as a chain polymer with intermolecular aurophilic bonding, while 5 shows an intramolecular Au(I)...Au(I) interaction. The gold(III) derivative Bu(4)N[Au(C(6)F(5))(3){SeC(6)H(4)(CH(2)NMe(2))-2}] (6) is obtained by reaction of [2-(Me(2)NCH(2))C(6)H(4)Se]K and Bu(4)N[AuBr(C(6)F(5))(3)], in a 1:1 molar ratio. These species exhibit luminescence which probably arises from a mixed (3)LMMCT and (3)MC excited state. The emission properties in these complexes seem to be useful for structural predictions and lead to the proposal of intermolecular aggregation in the solid state and frozen solution for complexes 1, 2, 3, whose crystal structures have not been elucidated.

The reaction of the phosphetane disulfide, FcP(S)S 2P(S)Fc ( 1) (Fc = (eta (5)-C 5H 5)Fe(eta (5)-C 5H 4)), the ferrocenyl analogue of the Lawesson reagent, with gold and palladium complexes leads to the unprecedented formation of phosphonodithioate ligands upon coordination to the metal centers. The reaction of 1 with gold complexes such as [AuCl(PR 3)] affords the species [Au{S 2P(OH)Fc}(PR 3)] (PR 3 = PPh 3 ( 2), PPh 2Me ( 3)), in which the phosphonodithioate ligand Fc(OH)PS 2 (-) has been formed. The same ligand is present in the compound [Au 2{S 2P(OH)Fc} 2].[N(PPh 3) 2]Cl ( 4), obtained by reaction of 1 with [N(PPh 3) 2][AuCl 2]. It crystallizes with one molecule of [N(PPh 3) 2]Cl, whereby complex 4 acts as an anion receptor and forms strong hydrogen bonds between the chloro and the hydroxyl groups. The reaction with palladium derivatives is different; two complexes, [Pd 2(S 4OP 2Fc 2) 2] ( 5) and [Pd 4Cl 4(S 4OP 2Fc 2) 2] ( 6), are obtained in molar ratio 2:1 and 1:1, respectively. In these complexes a new phosphonodithioate ligand is present and probably arises from the condensation of two molecules of Fc(OH)PS 2 (-). Complex 5 has also been characterized by X-ray methods.

The reaction of [AuCl(PR'3)] with KTeR, prepared from RTeTeR and K-selectride, gives the gold-tellurolate clusters [Au8(mu-TeR)8(PR'3)4] (R = Ph, Tol; PR'3 = PPh3, PPh2py) in high yield. This result contrasts with the one obtained from the reaction with thiolates or selenolates, from which mononuclear complexes are synthesized. The structures of these species have been determined and consist on three layers of gold and tellurium atoms in the ratio Au3Te2:Au2Te4:Au3Te2. There are short gold...gold interactions ranging from 2.9463(7) to 3.31132(7) A, and the clusters are composed of di- and tri-coordinated gold centers. The result is unprecedented in gold-chalcogenolate chemistry from which mononuclear species are expected and represents one of the few examples of gold-tellurolate derivatives. These species show an interesting luminescent behavior in the solid state (at 77 K) and in solution (both at 298 and 77 K).

A mixture of pyridoxalrhodanine, triethylphosphinegold(I) chloride, and sodium methoxide in methanol unexpectedly afforded the azacoumarin complex [Au(TS)(PEt3)] [HTS = 5-(hydroxymethyl)-8-methyl-3-thiol-7-azacoumarin], which was characterized by X-ray diffractometry. Its crystals consist of independent molecules in which the metal atom is bound to the azacoumarin [Au-S = 2.9458(18) A] and the phosphine [Au-P = 2.262(2) A] in an almost linear arrangement [P1-Au1-S1 = 176.93(7) degrees]. The complex showed better in vitro antitumor activity than cisplatin against the cisplatin-resistant cell line A2780cis.

The reactions of [AuClL] with Ag(2)O, where L represents the heterofunctional ligands PPh(2)py and PPh(2)CH(2)CH(2)py, give the trigoldoxonium complexes [O(AuL)(3)]BF(4). Treatment of these compounds with thio- or selenourea affords the triply bridging sulfide or selenide derivatives [E(AuL)(3)]BF(4) (E=S, Se). These trinuclear species react with Ag(OTf) or [Cu(NCMe)(4)]PF(6) to give different results, depending on the phosphine and the metal. The reactions of [E(AuPPh(2)py)(3)]BF(4) with silver or copper salts give [E(AuPPh(2)py)(3)M](2+) (E=O, S, Se; M=Ag, Cu) clusters that are highly luminescent. The silver complexes consist of tetrahedral Au(3)Ag clusters further bonded to another unit through aurophilic interactions, whereas in the copper species two coordination isomers with different metallophilic interactions were found. The first is analogous to the silver complexes and in the second, two [S(AuPPh(2)py)(3)](+) units bridge two copper atoms through one pyridine group in each unit. The reactions of [E(AuPPh(2)CH(2)CH(2)py)(3)]BF(4) with silver and copper salts give complexes with [E(AuPPh(2)CH(2)CH(2)py)(3)M](2+) stoichiometry (E=O, S, Se; M=Ag, Cu) with the metal bonded to the three nitrogen atoms in the absence of AuM interactions. The luminescence of these clusters has been studied by varying the chalcogenide, the heterofunctional ligand, and the metal.

The title compound, [Ag(CF3O3S)(C10H9N3)]n, is a chain polymer in which neighbouring monomeric units are related by a glide plane. The silver centre is four-coordinate; the donor atoms are one trifluoromethanesulfonate O atom and one pyridine N atom from each of two symmetry-related dipyridylamines, and an additional and unexpected Ag...C contact [2.6464 (16) A] is observed to a pyridine C atom. The chains are reinforced by one classical N-H...O and two 'weak' C-H...O hydrogen bonds.

The gold(I) selenolate compound [Au(2)(SePh)(2)(mu-dppf)] (dppf = 1,1'-bis(diphenylphosphino)ferrocene) has been prepared by reaction of [Au(2)Cl(2)(mu-dppf)] with PhSeSiMe(3) in a molar ratio 1:2. This complex reacts with gold(I) or gold(III) derivatives to give polynuclear gold(I)-gold(I) or gold(I)-gold(III) complexes of the type [Au(4)(mu-SePh)(2)(PPh(3))(2)(mu-dppf)](OTf)(2), [Au(3)(C(6)F(5))(3)(mu-SePh)(2)(mu-dppf)], or [Au(4)(C(6)F(5))(6)(mu-SePh)(2)(mu-dppf)], with bridging selenolate ligands. The reaction of [Au(2)(SePh)(2)(mu-dppf)] with 1 equiv of AgOTf leads to the formation of the insoluble Ag(SePh) and the compound [Au(2)(mu-SePh)(mu-dppf)]OTf. The complexes [Au(4)(C(6)F(5))(6)(mu-SePh)(2)(mu-dppf)] and [Au(2)(mu-SePh)(mu-dppf)]OTf (two different solvates) have been characterized by X-ray diffraction studies and show the presence of weak gold(I)-gold(III) interactions in the former and intra- and intermolecular gold(I)-gold(I) inter-actions in the later.

A new series of isostructural, brilliantly luminescent gold-silver complexes having the formula [Au3(mu3-E)Ag(PPh2py)3](BF4)2 where E = O, S, Se and Ph2Ppy = 2-diphenylphosphinopyridine has been synthesized and characterized. The structural core of these complexes is a Au3Ag metallophilically linked tetrahedron with a group-16 atom functioning as a mu3-ligand capping the three gold atoms. In the solid state, pairs of clusters are joined by two unsupported aurophilic interactions. The emission energy changes strikingly in going from O (blue) to S (yellow) and Se (orange). The luminescence from the E = O system is the first to be reported for a gold(I) oxo system. Additionally, the luminescent 4-methylpyridyl analogue with E = S has been prepared and structurally characterized. For E = S, Se, the change in emission energy with mu3-bridging atom provides a sound basis for an LMMCT assignment of the excited state while lifetime measurements support its spin-forbidden nature. Frozen glass measurements indicate the presence of a higher-energy emitting state for these systems, and for the E = O system, either LMMCT or metal-centered cluster-based emission can be proposed.

The digold complex [Au(2)(micro-G)(micro-dmpe)](KBr)(0.75) x 2H(2)O (dmpe=1,2-bis(dimethylphosphino)ethane (1)) has been prepared by nucleophilic attack of the guaninate dianion on the gold(I) atoms of [(AuBr)(2)(micro-dmpe)] and has been characterised by X-ray crystallography and spectroscopic studies. The structure of 1 consists of dinuclear nine-membered ring molecules, K(+) cations, Br(-) anions and water molecules, all of them involved in either weak K....O or hydrogen bonding interactions. Within the cyclic dinuclear molecules, gold(I) atoms are bridged on one side by the diphosphine ligand and on the other side by a doubly deprotonated guaninate anion coordinated through neighbouring N3 and N9 nitrogen atoms, with gold(I)....gold(I) interactions of 3.030(2) A. This is the first X-ray example showing an N3,N9-bridging mode for guanine. There are two types of K(+) cations in the structure, K1 and K2. The former interacts with water molecules to form a unique [K(H(2)O)(3)(micro-H(2)O)(2)K(H(2)O)(3)](2+) dipotassium unit whereas K2 interact with the O6 atom of the guaninate ligands and oxygen atoms of the dipotassium unit leading to a chain running along the c-axis. Each chain is interdigitated with four neighbouring ones to give rise to an intricate network in which Br1, Br2 and [K(H(2)O)(3)(micro-H(2)O)(2)K(H(2)O)(3)](2+) fit snugly into cavities defined by digold molecules. Complex 1 luminescence at room temperature and 77 K in the solid state with excitation maxima at 385 nm and emission maxima at 451.8 and 448.7 nm, respectively. The emission spectrum of a saturated solution of 1 in DMSO (dimethyl sulfoxide) shows the maximum at about 440 nm.

The reactions of [N(3)P(3)Cl(6)] with one, two, or three equivalents of the difunctional 1,2-closo-carborane C(2)B(10)H(10)[CH(2)OH](2) and K(2)CO(3) in acetone have been investigated. These reactions led to the new spiro-closo-carboranylphosphazenes gem-[N(3)P(3)Cl(6-2n)[(OCH(2))(2)C(2)B(10)H(10)](n)] (n=1 (1), 2 (2)) and the first fully carborane-substituted phosphazene gem-[N(3)P(3)[(OCH(2))(2)C(2)B(10)H(10)](3)] (3). A bridged product, non-gem-[N(3)P(3)Cl(4)[(OCH(2))(2)C(2)B(10)H(10)]] (4), was also detected. The reaction of the well-known spiro derivatives [N(3)P(3)Cl(2)(O(2)C(12)H(8))(2)] and [N(3)P(3)Cl(4)(O(2)C(12)H(8))] with the same carborane-diol and K(2)CO(3) in acetone gave the new compounds gem-[N(3)P(3)(O(2)C(12)H(8))(3-n)[(OCH(2))(2)C(2)B(10)H(10)](n)] (n=1 (5) or 2 (6), respectively), without signs of intra- or intermolecularly bridged species. Upon treatment with NEt(3) in acetone, compound 5 was converted into the corresponding nido-carboranylphosphazene. However, the reaction of gem-[N(3)P(3)(O(2)C(12)H(8))(2)[(OCH(2))(2)C(2)B(10)H(10)]] (5) with NEt(3) in ethanol instead of acetone proceeded in a different manner to give the new compound (NHEt(3))(2)[N(3)P(3)(O(2)C(12)H(8))(2)(O)[OCH(2)C(2)B(9)H(10)CH(2)OCH(2)CH(3)]] (7). For compounds with two 2,2'-dioxybiphenyl units, gem-[N(3)P(3)(O(2)C(12)H(8))(2)[(OCH(2))(2)C(2)B(10)H(10)]] (5), (NHEt(3))[N(3)P(3)(O(2)C(12)H(8))(2)[(OCH(2))(2)C(2)B(9)H(10)]] (8), and (NHEt(3))(2)[N(3)P(3)(O(2)C(12)H(8))(2)(O)[OCH(2)C(2)B(9)H(10)CH(2)OCH(2)CH(3)]] (7), a mixture of different stereoisomers may be expected. However, for 5 and 7 only the meso compounds seem to be formed, with the same (R,S)-configuration as in the precursor [N(3)P(3)Cl(2)(O(2)C(12)H(8))(2)]. The reaction of 5 to give 8 seems to proceed with a change of configuration at one phosphorus center, giving a racemic mixture. The crystal structures of the nido-carboranylphosphazenes 7 and 8 have been confirmed by X-ray diffraction methods.

The dinuclear head-to-tail complexes [M(2)(PPh(2)CH(2)SPh)(2)](2+) (M = Cu (1), Ag (2a, 2b), Au (4)) are obtained either by reaction of [Cu(CH(3)CN)(4)]CF(3)SO(3), AgClO(4), AgCF(3)SO(3), with equimolecular amounts of PPh(2)CH(2)SPh or of [AuCl(PPh(2)CH(2)SPh)] (3), prepared by reaction of [AuCl(tht)] and PPh(2)CH(2)SPh, with AgCF(3)SO(3). The crystal structures of complexes 2a and 4 have been established by X-ray diffraction studies. Ab initio HF/II and MP2/II calculations have been performed on the [M(2)(H(2)PCH(2)SH)(2)](2+) model, indicating that metallophilic attraction is indeed present for all the coinage metals as a correlation effect and is strengthened in the case of gold by relativistic effects. Since experimental and theoretically predicted geometries are in close agreement, we assume that our calculations are accurate enough to obtain valid conclusions.