Gold and silver complexes with the ferrocenyl phosphine FcCH2PPh2

Linear gold(I) and silver(I) complexes with the ferrocenyl phosphine FcCH2PPh2 [Fc = (eta5-C5H5)Fe(eta5-C5H4)] of the types [AuR(PPh2CH2Fc)], [M(PPh3)(PPh2CH2Fc)]OTf, and [M(PPh2CH2Fc)2]OTf (M = Au, Ag) have been obtained. Three-coordinate gold(I) and silver(I) derivatives of the types [AuCl(PPh2CH2Fc)2] and [M(PPh2CH2Fc)3]X (M = Au, X = ClO4; M = Ag, X = OTf) have been obtained from the corresponding gold and silver precursors in the appropriate molar ratio, although some of them are involved in equilibria in solution. The crystal structures of [AuR(PPh2CH2Fc)] (R = Cl, C6F5), [AuL(PPh2CH2Fc)]OTf (L = PPh3, FcCH2PPh2), [Au(C6F5)3(PPh2CH2Fc)], and [Ag(PPh2CH2Fc)3]OTf have been determined by X-ray diffraction studies.     

Auration, argentation, and mercuration reactions of an iridaphosphirene

The reactions of the iridaphosphirene complex [Ir{=C(tBu)P(Cy)}(CO)(PPh3)2] (Cy = cyclohexyl) with either [AuCl(tht)] (tht = tetrahydrothiophene) or AgCl result in the products [Ir{=C(tBu)P[M(Cl)](Cy)}(CO)(PPh3)2], M = Au or Ag. The aurated product can additionally be obtained on reaction of the iridaphosphirene with [AuCl(CNtBu)], via loss of the isocyanide ligand. Treatment of [Ir{=C(tBu)P(Cy)}(CO)(PPh3)2] with [AuCl(PPh3)] in the presence of silver triflate leads to the isolation of the salt, [Ir{=C(tBu)P[Au(PPh3)](Cy)}(CO)(PPh3)2][SO3CF3]. Reaction of the iridaphosphirene with PhHgCl in the absence or presence of silver triflate affords the mercurated species [Ir{=C(tBu)P[Hg(Ph)](Cy)}(CO)(PPh3)2]X, X = Cl or CF3SO3, respectively. The former exhibits a weakly mercury-coordinated chloride ion. The X-ray crystal structures of all of the complexes are described.     

Group 11 complexes with unsymmetrical P,S and P,Se disubstituted ferrocene ligands

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), [Au2{Fc(SPh)PPh2}2](ClO4)2, [Au(C6F5)2{Fc(SePh)PPh2}]ClO4, [Au(C6F5)3{Fc(EPh)PPh2}], [Au2(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...Cl or Au...Se interactions. The complex [Ag(OTf){Fc(SePh)PPh2}] forms one-dimensional chains through trifluoromethanesulfonate bridging ligands.     

Heteropolynuclear phosphide complexes: phosphorus as unique atom bridging coinage metal centres

In this paper we describe the synthesis and reactivity of the diphenylphosphine derivatives [Au(C6F5)(PPh2H)] and trans-[Au(C6F5)2(PPh2H)2]ClO4. Reactions of the latter or the neutral [Au(C6F5)3(PPh2H)] with the appropriate Group 11 metal reagents (M = Au, Ag, Cu) in the presence of acetylacetonate afford a series of novel Au(III)-M phosphido-bridged complexes, which have been scarcely represented to date. The crystal structure of the tetranuclear [(Au(C6F5)2(mu-PPh2)2Ag)2] and the dinuclear [Au(C6F5)3(mu-PPh2)M(PPh3)] (M = Au,Ag) complexes were established by X-ray diffraction methods. The synthesis and deprotonating activity of the anionic gold(III) complex PPN[Au(C6F5)3(acac)] (PNN = [N(PPh3)2]+) was studied.     

The first acetimine gold(I) and gold(III) complexes and the first acetonine complexes

Ketimino(phosphino)gold(I) complexes of the type [Au[NR=C(Me)R']L]X (X = ClO4, R = H, L = PPh3, R'=Me (la), Et (2a); L=PAr3 (Ar=C6H4OMe-4), R'=Me (1b), Et (2b); L=PPh3, R=R'=Me (3); X= CF3SO3 (OTf), L=PPh3, R=R'=Me (3'); R=Ar, R'=Me (4)) have been prepared from [Au(acac)L] (acac = acetyl acetonate) and ammonium salts [RNH3]X dissolved in the appropriate ketone MeC(O)R'. Complexes [Au(NH=CMe2)2]X (X = C1O4 (6), OTf (6')) were obtained from solutions of [Au(NH3)2]X in acetone. The reaction of 6 with PPN[AuCl2] or with PhICl2 gave [AuCl(NH=CMe2)] (7) or [AuCI2(NH=CMe2)2]ClO4 (8), respectively. Complex 7 was oxidized with PhICl2 to give [AuCl3(NH=CMe2)] (9). The reaction of [AuCl(tht)] (tht = tetrahydrothiophene), NaClO4, and ammonia in acetone gave [Au(acetonine)2]ClO4 (10) (acetonine = 2,2,4,4,6-pentamethyl-2,3,4,5-tetrahydropyrimidine) which reacted with PPh3 or with PPN[AuCl2] to give [Au(PPh3)(acetonine)]ClO4 (11) or [AuCl(acetonine)] (12), respectively. Complex 11 reacts with [Au(PPh3)(Me2CO)]ClO4 to give [(AuPPh3)2(mu-acetonine)](ClO4)2 (13). The reaction of AgClO4 with acetonine gave [Ag(acetonine)(OClO3)] (14). The crystal structures of [Au(NH2Ar)(PPh3)]OTf (5), 6' and 10 have been determined.     

Tetranuclear [Rh4(mu-PyS2)2(diolefin)4] complexes as building blocks for new inorganic architectures: synthesis of coordination polymers and heteropolynuclear complexes with electrophilic d8 and d10 metal fragments

The reaction of [Rh4(mu-PyS2)2(cod)4] (PyS2 = 2,6-pyridinedithiolate, cod = 1,5-cyclooctadiene) with CF3SO3Me gave the cationic complex [Rh(4)(mu-PyS(2)Me)(2)(cod)4][CF3SO3]2 (1) with two 6-(thiomethyl)pyridine-2-thiolate bridging ligands from the attack of Me+ at the terminal sulfur atoms of the starting material. Under identical conditions [Rh4(mu-PyS2)2(tfbb)4] (tfbb = tetrafluorobenzobarrelene) reacted with CF3SO3Me to give the mixed-ligand complex [Rh(4)(mu-PyS2)(mu-PyS2Me)(tfbb)4][CF3SO3] 2. The nucleophilicity of the bridging ligands in the complexes [Rh4(mu-PyS2)2(diolefin)4] was exploited to prepare heteropolynuclear species. Reactions with [Au(PPh3)(Me2CO)][ClO4] gave the hexanuclear complexes [(PPh3)2Au2Rh4(mu-PyS2)2(diolefin)4][ClO4]2 (diolefin = cod (3), tfbb (4)). The structure of 4, solved by X-ray diffraction methods, showed the coordination of the [Au(PPh3)]+ fragments to the peripheral sulfur atoms in [Rh4(mu-PyS2)2(diolefin)4] along with their interaction with the neighbor rhodium atoms. Neutral coordination polymers of formula [ClMRh4(mu-PyS2)2(diolefin)4]n (M = Cu (5, 6), Au (7)) result from the self-assembly of alternating [Rh4(mu-PyS2)2(diolefin)4] ([Rh4]) blocks and MCl linkers. The formation of the infinite polymetallic chains was found to be chiroselective for M = Cu; one particular chain contains exclusively homochiral [Rh4] complexes. Cationic heterometallic coordination polymers of formula [MRh4(mu-PyS2)2(diolefin)4]n[BF4]n (M = Ag (8, 9), Cu (10, 11)) and [Rh5(mu-PyS2)2(diolefin)5]n[BF4]n (12, 13) result from the reactions of [Rh4] with [Cu(CH2CN)4]BF4, AgBF4, and [Rh(diolefin)(Me2CO)2]BF4, respectively. The heterometallic coordination polymers exhibit a weak electric conductivity in the solid state in the range (1.2-2.8) x 10(-7) S cm(-1).     

Group 11 complexes with the bis(3,5-dimethylpyrazol-1-yl)methane ligand. How secondary bonds can influence the coordination environment of Ag(I): the role of coordinated water in [Ag2(mu-L)2(OH2)2](OTf)2

The complexation properties of the ligand bis(3,5-dimethylpyrazol-1-yl)methane (L) towards group 11 metals have been studied. The reaction in a 1 : 1 molar ratio with [Cu(NCMe)4]PF6 or Ag(OTf) complexes gives the mononuclear [CuL(NCMe)]PF6 (1), with crystallographic mirror symmetry, or dinuclear [Ag2(mu-L)2](OTf)2 (2) (OTf = trifluoromethanesulfonate) in which the ligand bridges both silver centres, an unprecedented mode of coordination for this type of ligands. Compound 2 crystallizes with two water molecules and forms a supramolecular structure through classical hydrogen bonding. The reaction in a 2 : 1 ratio affords in both cases the four-coordinated derivatives [ML2]X (M = Cu, X = PF6 (3); Ag, X = OTf 4). The treatment of [Ag(OTf)(PPh3)] with the ligand L gives [AgL(PPh3)]OTf (5). The gold(I) derivative [Au2(C6F5)2(mu-L)] (6) has also been obtained by reaction of L with two equivalents of [Au(C6F5)(tht)]. These complexes present a luminescent behaviour at low temperature; the emissions being mainly intraligand but enhanced after coordination of the metal. Compounds 1-4 have been characterized by X-ray crystallography. DFT studies showed that, in the silver complex 2, coordination of H2O to Ag in the binuclear complex is favoured by formation of a hydrogen-bonding network, involving the triflato anion, and releasing enough energy to allow distortion of the Ag2 framework.     

Unprecedented luminescent heteropolynuclear aggregates with gold thiolates as building blocks

The reaction of [AuCl(P-N)], in which P-N represents a heterofunctional phosphine ligand, with pentafluorothiophenol, HSC(6)F(5), gives the thiolate gold derivatives [Au(SC(6)F(5))(P-N)] (P-N = PPh(2)py (1), PPh(2)CH(2)CH(2)py (2), or PPhpy(2) (3)). Complex [Au(SC(6)F(5))(PPh(2)py)] (1) reacts with [Au(OTf)(PPh(2)py)] in a 1:1 or 1:2 molar ratio to afford the di- or trinuclear species [Au(2)(μ-SC(6)F(5))(PPh(2)py)(2)]OTf (4) and [Au(3)(μ(3)-SC(6)F(5))(PPh(2)py)(3)](OTf)(2) (5), with the thiolate acting as a doubly or triply bridging ligand. The reactivity of the mononuclear compounds [Au(SC(6)F(5))(P-N)] toward silver or copper salts in different ratios has been investigated. Thus, the treatment of [Au(SC(6)F(5))(P-N)] with Ag(OTf) or [Cu(NCMe)(4)]PF(6) in a 1:1 molar ratio gives complexes of stoichiometry [AuAg(OTf)(μ-SC(6)F(5))(P-N)] (P-N = PPh(2)py (6), PPh(2)CH(2)CH(2)py (7), or PPhpy(2) (8)) or [AuCu(μ-SC(6)F(5))(P-N)(NCMe)]PF(6) (P-N = PPh(2)py (9), PPh(2)CH(2)CH(2)py (10), or PPhpy(2) (11)). These complexes crystallize as dimers and display different coordination modes of the silver or copper center, depending on the present functionalized phosphine ligand. The treatment of [Au(SC(6)F(5))(PPh(2)py)] with silver and copper compounds in other molar ratios has been carried out. In a 2:1 ratio, the complexes [Au(2)M(μ-SC(6)F(5))(2)(μ-PPh(2)py)(2)]X (M = Ag, X = OTf (12); M = Cu, X = PF(6) (13)) are obtained. The same reaction in a 4:3 molar ratio affords the species [Au(4)M(2)(μ-SC(6)F(5))(3)(μ-PPh(2)py)(4)]X(3) (M = Ag, X = OTf (14); M = Cu, X = PF(6) (15)). The crystal structures of some of these complexes reveal different interactions among the metallic d(10) centers. The complexes display dual emission. The band at higher energy has been attributed to intraligand (IL) transitions, and the one at lower energy has been assigned to a ligand to metal (LM) charge transfer process. The latter emission is modulated by the heterometal (silver or copper).     

A family of alkynylgold(III) complexes [AuI(mu-{CH2}2PPh2)2Au(III)(C triple bond CR)2] (R = Ph, tBu, Me3Si): facile and reversible comproportionation of gold(I)/gold(III) to digold(II)

The symmetric digold(II)dichloride bis(ylide) complex [Au2Cl2(mu-{CH2}2PPh2)2] reacts with acetylides to form the asymmetric heterovalent gold(I)/gold(III) complexes [AuI(mu-{CH2}2PPh2)2AuIII(CCR)2] [R = Ph, tBu, and SiMe3], the phenyl analogue of which was characterized by X-ray crystallography. These compounds represent the first examples of gold(III) complexes containing two acetylide ligands. [AuI(mu-{CH2}2PPh2)2AuIII(CCPh)2] undergoes a reversible comproportionation reaction upon treatment with [Ag(ClO4)tht] to give the symmetric digold(II) cationic complex [Au2(tht)2(mu-{CH2}2PPh2)2](ClO4)2. If this complex is treated with phenylacetylene in the presence of base, the heterovalent gold(I)/gold(III) complex is re-formed. This reversible interconversion between binuclear gold(I)/gold(III) and digold(II) bis(ylide) complexes is unprecedented.     

Group 11 complexes containing the [C5(CN)5]- ligand; 'coordination-analogues' of molecular organometallic systems

The reactions of Na[C(5)(CN)(5)] (Na[1]) with group 11 phosphine complexes [(P)(n)MCl] (M = Cu, Ag, Au, P = Ph(3)P; M = Cu, P = dppe (Ph(2)PCH(2)CH(2)PPh(2))] give a range of compounds containing the pentacyanocyclopentadienide ligand, [C(5)(CN)(5)](-) (1). The new complexes [(Ph(3)P)(2)M{1}](2) [M = Cu (3); M = Ag (5)], [(Ph(3)P)(3)Ag{1}] (4), [(dppe)(3)Cu(2){1}(2)] (6) and [Au(PPh(3))(2)][1] (7) include the first complete series of group 11 complexes of any cyclopentadienide ligand to be structurally characterised.     

Syntheses and structures of thermally stable diketiminato complexes of gold and copper

While most metallic elements across the Periodic Table form stable chelating β-diketiminato complexes, examples of Au(I) are conspicuous by their absence. We report here the reaction of K[HC(F(3)CC=NR)(2)] with AuCl(PPh(3)) which provides a rare example of a thermally stable gold(I) diketiminato complex, (Ph(3)P)Au[RN=C(CF(3))CH(CF(3))C=NR] [R = 3,5-C(6)H(3)(CF(3))(2)]. The complex is highly fluxional in solution but in the solid state adopts a U-conformation. By contrast, the analogous reaction of K[HC(F(3)CC=NR)(2)] with CuBr(PPh(3))(3) gives the rigid 18-electron chelate complex (Ph(3)P)(2)Cu[κ(2)-HC{(CF(3))C=NR}(2)].     

New group 11 complexes with metal-selenium bonds of methyldiphenylphosphane selenide: a solid state, solution and theoretical investigation

Reactions between methyldiphenylphosphane selenide, SePPh(2)Me, and different group 11 metal starting materials {CuCl, [CuNO(3)(PPh(3))(2)], AgOTf, [AgOTf(PPh(3))] (OTf = OSO(2)CF(3)), [AuCl(tht)], [Au(C(6)F(5))(tht)] and [Au(C(6)F(5))(3)(tht)] (tht = tetrahydrothiophene)} were performed in order to obtain several new species with metal-selenium bonds. The new complexes [CuCl(SePPh(2)Me)] (1), [AgOTf(SePPh(2)Me)] (2), [AuCl(SePPh(2)Me)] (5), [Au(C(6)F(5))(SePPh(2)Me)] (6) and [Au(C(6)F(5))(3)(SePPh(2)Me)] (7) were isolated and structurally characterized in solution by multinuclear NMR spectroscopy ((1)H, (31)P, (77)Se and (19)F where appropriate). Solid products were isolated also from the reactions between SePPh(2)Me and [CuNO(3)(PPh(3))(2)] or [AgOTf(PPh(3))], respectively. NMR experiments, including low temperature (1)H and (31)P NMR, revealed for them a dynamic behaviour in solution, involving the transfer of selenium from PPh(2)Me to PPh(3). In case of the isolated silver(i) containing solid an equilibrium between, respectively, monomeric [AgOTf(PPh(3))(SePPh(2)Me)] (3) and [AgOTf(PPh(2)Me)(SePPh(3))] (4), and dimeric [Ag(PPh(3))(μ-SePPh(2)Me)](2)(OTf)(2) (3a) and [Ag(PPh(2)Me)(μ-SePPh(3))](2)(OTf)(2) (4a) species was observed in solution. In case of the isolated copper(i) containing solid the NMR studies brought no clear evidence for a similar behaviour, but it can not be excluded in a first stage of the reaction. However the transfer of selenium between the two triorganophosphanes takes place also in this case, but the NMR spectra suggest that the final reaction mixture contains the free triorganophospane selenides SePPh(2)Me and SePPh(3) as well as the complex species [CuNO(3)(PPh(3))(2)], [CuNO(3)(PPh(2)Me)(2)] and [CuNO(3)(PPh(3))(PPh(2)Me)] in equilibrium. Single-crystal X-ray diffraction studies revealed monomeric structures for the gold(I) 6 and gold(III) 7 complexes. In case of compound 6 weak aurophilic gold(I)···gold(I) contacts were also observed in the crystal. DFT calculations were performed in order to understand the solution behaviour of the silver(I) and copper(I) species containing both P(III) and P(V) ligands, to verify the stability of possible dimeric species and to account for the aurophilic interactions found for 6. In addition, the nature of the electronic transitions involved in the absorption/emission processes observed for 6 and 7 in the solid state were also investigated by means of TD-DFT calculations.     

Photosensitive azobispyridine gold(I) and silver(I) complexes

The neutral and cationic dinuclear gold(I) compounds [(μ-N-N)(AuR)(2)] (N-N = 2,2'-azobispyridine (2-abpy), 4,4'-azobispyridine (4-abpy); R = C(6)F(5), C(6)F(4)OC(12)H(25)-p, C(6)F(4)OCH(2)C(6)H(4)OC(12)H(25)-p) and [(μ-N-N){Au(PR(3))}(2)](CF(3)SO(3))(2) (N-N = 2-abpy, 4-abpy, R = Ph, Me) have been obtained by displacement of a weakly coordinated ligand by an azobispyridine ligand. The corresponding silver(I) dinuclear [(μ-2-abpy){Ag(CF(3)SO(3))(PPh(3))}(2)] and polynuclear [{Ag(CF(3)SO(3))(4-abpy)}(n)] compounds have been obtained. The molecular structures of [(μ-2-abpy){Au(PPh(3))}(2)](CF(3)SO(3))(2) and [(μ-4-abpy){Au(PMe(3))}(2)](CF(3)SO(3))(2) have been confirmed by X-ray diffraction studies and feature linear gold(I) centers coordinated by pyridyl groups, and non-coordinated azo groups. In contrast the X-ray structure of [(2-abpy){Ag(CF(3)SO(3))(PPh(3))}(2)] shows tetracoordinated silver(I) centers involving chelating N-N coordination by pyridyl and azo nitrogen atoms. The gold(I) compounds with a long alkoxy chain do not behave as liquid crystals, and decompose before their melting point. The soluble gold(I) derivatives are photosensitive in solution and isomerize to the cis azo isomer under UV irradiation, returning photochemically or thermally to the most stable initial trans isomer. The silver(I) derivative [(2-abpy){Ag(CF(3)SO(3))(PPh(3))}(2)] also photoisomerizes in solution under UV irradiation, showing that its solid state structure, which would block isomerization by azo coordination, is easily broken. These processes have been monitored by UV-vis absorption and (1)H NMR spectroscopy. All these compounds are non-emissive in the solid state, even at 77 K.     

A new route to coordination complexes of nitroxyl (HN=O) via insertion reactions of nitrosonium triflate with transition-metal hydrides

Nitrosonium triflate reacts with cold methylene chloride solutions of mer,trans-ReH(CO)3(PPh3)2 (1) with 1,1-insertion of NO+ into the Re-H bond to give the orange nitroxyl complex [mer,trans-Re(NH=O)(CO)3(PPh3)2][SO3CF3] (3) in 86% isolated yield. Use of [NO][PF6] or [NO][BF4] gives analogous insertion products at low temperature, which decompose on warning to ambient temperature to the fluoride complex mer,trans-ReF(CO)3(PPh3)2 (4). A related 1,1-insertion is observed in the reaction of 1 with [PhN2][PF6] in acetone that affords the yellow-orange phenyldiazene salt [mer,trans-Re(NH=NPh)(CO)3(PPh3)2][PF6] (2), which has been characterized by X-ray crystallographic methods. The methyl derivative mer,trans-Re(CH3)(CO)3(PPh3)2 (5) also undergoes a 1,1-insertion reaction with [NO][SO3CF3] to give the nitrosomethane adduct [mer,trans-Re{N(CH3)=O}(CO)3(PPh3)2][SO3CF3] (6) as red crystals in 75% yield. The nitroxyl complex [cis,trans-OsBr(NH=O)(CO)2(PPh3)2][SO3CF3] (8) can be similarly prepared as orange crystals in 52% yield by reaction of cis,trans-OsHBr(CO)2(PPh3)2 (7) with [NO][SO3CF3] in cold methylene chloride solution.     

Experimental and theoretical studies of the d8-d10 interaction between Pd(II) and Au(I): bis(chloro[(phenylthiomethyl)diphenylphosphine]gold(I))- dichloropalladium(II) and related systems

The reaction between thioether phosphine gold(I) precursors such as [AuCl(Ph2PCH2SPh)], 1, or [Au(Ph2PCH2SPh)2]CF3SO3 and PdCl2(NCPh)2 affords the new compounds [(AuCl(Ph2PCH2SPh)2PdCl2], 2, and [AuPdCl2(Ph2PCH2SPh)2]CF3SO3, 3. The crystal structure of complex 2 has the sterically unhindered Pd(II) and Au(I) at a distance of 314 pm. Quasirelativistic pseudopotential calculations on [AuPdCl3(PH2CH2SH)(SH2)] models give short Au-Pd distances at the second-order M?ller-Plesset (MP2) level and long Au-Pd distances at Hartree-Fock (HF) level. A detailed analysis of the Au-Pd interaction shows dominant dispersion, some ionic contributions, and no net charge transfer between the metals.     

Ancillary ligands and spectator cations as controlling factors in the construction of coordination and hydrogen-bonded networks with the tert-Bu-C triple bond C superset Ag(n) (n=4, 5) supramolecular synthon

Supramolecular networks constructed with the tBu--C[triple bond]C superset Ag(n) (n=4 or 5) metal-ligand synthon and trifluoroacetate have been transformed through the introduction of ancillary terminal nitrile ligands, from acetonitrile through propionitrile to tert-butyronitrile, giving rise to a 2D coordination network in AgC[triple chemical bond]CtBu3 AgCF(3)CO(2)H(2)O (1), a 2D hydrogen-bonded network in AgC[triple chemical bond]CtBu5 AgCF(3)CO(2)4 CH(3)CNH(2)O (2), a 2D hybrid coordination/hydrogen-bonded network in AgC[triple chemical bond]CtBu3 AgCF(3)CO(2)CH(3)CH(2)CN2 H(2)O (3), and another 2D coordination network in AgC[triple chemical bond]CtBu4 AgCF(3)CO(2) (CH(3))(3)CCN2 H(2)O (4). Concomitantly, the linkage modes between adjacent ethynide-bound Ag(n) aggregates in these compounds are also changed. A layer-type hydrogen-bonded host lattice in isostructural AgC[triple chemical bond]CtBu4 AgCF(3)CO(2)(R(4)N)(CF(3)CO(2)) 2 H(2)O (R(4)=BnMe(3), 5; R(4)=Et(4), 6; R(4)=nPr(4), 7) is obtained by introducing quaternary ammonium cations as guest templates, which occupy the interstices and thereby mediate the interlayer separation. Use of the bulky nBu(4)N(+) cation leads to disruption of the host network in AgC[triple bond]CtBu4 AgCF(3)CO(2)3[(nBu(4)N)(CF(3)CO(2))]H(2)O (8) with generation of a discrete dense nido-Ag(5) cluster.     

Betaine-induced assembly of neutral infinite columns and chains of linked silver(I) polyhedra with embedded acetylenediide

Ten polymeric silver(I) double salts containing embedded acetylenediide: [(Ag2C2)2(AgCF3CO2)9(L1)3] (1), [(Ag2C2)2(AgCF3CO2)10(L2)3]H2O (2), [(Ag2C2)(AgCF3CO2)4(L3)(H2O)]0.75 H2O (3), [(Ag2C2)(1.5)(AgCF3CO2)7(L4)2] (4), [(Ag2C2)(AgCF3CO2)7(L5)2(H2O)] (5), [(Ag2C2) (AgC2F5CO2)7(L1)3(H2O)] (6), [(Ag2C2)(AgCF3CO2)7(L1)3(H2O)]2 H2O (7), [(Ag2C2)(AgC2F5CO2)6(L3)2] (8), [(Ag2C2)2(AgC2F5CO2)12(L4)2(H2O)4]H2O (9), and [(Ag2C2)(AgCF3CO2)6(L3)2(H2O)]H2O (10) have been isolated by varying the types of betaines, the perfluorocarboxylate ligands employed, and the reaction conditions. Single-crystal X-ray analysis has shown that 1-4 all have a columnar structure composed of fused silver(I) double cages, with C2(2-) species embedded in its stem and an exterior coat comprising anionic and zwitterionic carboxylates. For 5 and 6, single silver(I) cages are linked into a beaded chain through both types of carboxylate ligands. In 7, two different coordination modes of L1 connect the silver(I) polyhedra into a chain. For 8, the mu(2)-O,O' coordination mode of L3 connects the silver(I) double cages into a chain. Compound 9 exhibits a two-dimensional architecture generated from the cross-linkage of double cages by C2F5CO2-, L4, and [Ag2(C2F5CO2)2] units. Similar to 9, 10 is also a two-dimensional structure, which is formed by connecting the chains of linked double cages through [Ag2(CF3CO2)2] bridging.     

Synthesis, structural characterization, and theoretical studies of gold(I) and gold(I)-gold(III) thiolate complexes: quenching of gold(I) thiolate luminescence

The gold(I) thiolate complexes [Au(2-SC6H4NH2)(PPh3)] (1), [PPN][Au(2-SC6H4NH2)2] (2) (PPN = PPh3=N=PPh3), and [{Au(2-SC6H4NH2)}2(mu-dppm)] (3) (dppm = PPh2CH2PPh2) have been prepared by reaction of acetylacetonato gold(I) precursors with 2-aminobenzenethiol in the appropriate molar ratio. All products are intensely photoluminescent at 77 K. The molecular structure of the dinuclear derivative 3 displays a gold-gold intramolecular contact of 3.1346(4) A. Further reaction with the organometallic gold(III) complex [Au(C6F5)3(tht)] affords dinuclear or tetranuclear mixed gold(I)-gold(III) derivatives with a thiolate bridge, namely, [(AuPPh3){Au(C6F5)3}(mu2-2-SC6H4NH2)] (4) and [(C6F5)3Au(mu2-2-SC6H4NH2)(AudppmAu)(mu2-2-SC(6)H4NH2)Au(C6F5)3] (5). X-ray diffraction studies of the latter show a shortening of the intramolecular gold(I)-gold(I) contact [2.9353(7) or 2.9332(7) A for a second independent molecule], and short gold(I)-gold(III) distances of 3.2812(7) and 3.3822(7) A [or 3.2923(7) and 3.4052(7) A] are also displayed. Despite the gold-gold interactions, the mixed derivatives are nonemissive compounds. Therefore, the complexes were studied by DFT methods. The HOMOs and LUMOs for gold(I) derivatives 1 and 3 are mainly centered on the thiolate and phosphine (or the second thiolate for complex 2), respectively, with some gold contributions, whereas the LUMO for derivative 4 is more centered on the gold(III) fragment. TD-DFT results show a good agreement with the experimental UV-vis absorption and excitation spectra. The excitations can be assigned as a S --> Au-P charge transfer with some mixture of LLCT for derivative 1, an LLCT mixed with ILCT for derivative 2, and a S --> Au...Au-P charge transfer with LLCT and MC for derivative 3. An LMCT (thiolate --> Au(III) mixed with thiolate --> Au-P) excitation was found for derivative 4. The differing nature of the excited states [participation of the gold(III) fragment and the small contribution of sulfur] is proposed to be responsible for quenching the luminescence.     

Vapochromic behavior of {Ag2(Et2O)2[Au(C6F5)2]2}n with volatile organic compounds

The vapochromic behaviors of {Ag2L2[Au(C6F5)2]2}n (L = Et2O (1), Me2CO (2), THF (3), CH3CN (4)) were studied. {Ag2L2[Au(C6F5)2]2}n (L = Et2O (1)) was synthesized by the reaction of [Bu4N][Au(C6F5)2] with AgOClO3 in 1:1 molar ratio in CH2Cl2/Et2O (1:2). 1 was used as starting material with THF to form {Ag2L2[Au(C6F5)2]2}n (L = THF (3)). 3 crystallizes in the monoclinic space group C2/c and consists of tetranuclear units linked together via aurophilic contacts resulting in the formation of a 1D polymer that runs parallel to the crystallographic z axis. The gold(I) atoms are linearly coordinated to two pentafluorophenyl groups and display additional Au...Ag close contacts within the tetranuclear units with distances of 2.7582(3) and 2.7709(3) A. Each silver(I) center is bonded to the two oxygen atoms of the THF molecules with a Ag-O bond distance of 2.307(3) A. TGA analysis showed that 1 loses two molecules of the coordinated solvent per molecular unit (1st one: 75-100 degrees, second one: 150-175 degrees C), whereas 2, 3, and 4 lose both volatile organic compounds (VOCs) and fluorinated ligands in a less well defined manner. Each complex loses both the fluorinated ligands and the VOCs by a temperature of about 325 degrees C to give a 1:1 gold/silver product. X-ray powder diffraction studies confirm that the reaction of vapors of VOCs with 1 in the solid state produce complete substitution of the ether molecules by the new VOC. The VOCs are replaced in the order CH3CN > Me2CO > THF > Et2O, with the ether being the easiest to replace. {Ag2(Et2O)2[Au(C6F5)2]2}n and {Ag2(THF)2[Au(C6F5)2]2} n both luminesce at room temperature and at 77 K in the solid state. Emission maxima are independent of the excitation wavelength used below about 500 nm. Emission maxima are obtained at 585 nm (ether) and 544 nm (THF) at room temperature and at 605 nm (ether) and 567 nm (THF) at 77 K.     

Synthesis and coordination chemistry of an alkyne functionalised bis(pyrazolyl)methane ligand

The alkyne functionalised bidentate N-donor ligand (2-propargyloxyphenyl)bis(pyrazolyl)methane was prepared in high yield from the reaction of (2-hydroxyphenyl)bis(pyrazolyl)methane with propargyl bromide in the presence of base. A series of transition-metal complexes including [MCl2] (M=Cu, Co, Ni, Zn, Pt), [M2](NO3)2 (M=Cu, Co, Ni, Zn), [Ag]NO3 and [Pd(dppe)](OTf)2 were prepared and characterised by spectroscopic techniques. In addition, ligand as well as the Co(II) and Zn(II) complexes [CoCl2]2, [ZnCl2] were structurally characterized by single-crystal X-ray diffraction. The organometallic gold(I) and platinum(II) acetylide complexes [Pz2CH(C6H(4)-2-OCH2C[triple bond, length as m-dash]CAuPPh3)] and trans-[{Pz2CHC6H(4)-2-OCH2C[triple bond, length as m-dash]C}2Pt(PPh3)2] were prepared from and [AuCl(PPh3)] and trans-[PtCl2(PPh3)2], respectively. Treatment of these complexes with [Pd(OTf)2(dppe)] or [Cu(MeCN)4]PF6 results in formation of the cationic, mixed-metal complexes, which were isolated (Pt/Pd, Au/Pt) or detected by electrospray mass spectrometry (Au/Cu, Pt/Cu).