Structure and magnetic properties of the ferromagnetic Cu3Cl12(6)- trimer in [(NH3C2H4)3NH]2Cu3Cl14

The crystal structure consists of a strongly hydrogen bonded network of tris(N-ethylammonium)ammonium cations, Cu3Cl12(6)- trimeric species, and Cl- anions. The Cu3Cl12(6)- trimers are formed by two distorted tetrahedral CuCl4(2)- anions linked to a central square planar CuCl4(2)- anion via semicoordinate Cu-Cl...Cu mu1 bridges. The central copper ion shows only small deviations from ideal D4h symmetry, while the terminal copper ions show a mild distortion from D2d symmetry with an average trans Cl-Cu-Cl angle of 136.0 degrees. The semicoordinate linkages provide a ferromagnetic exchange pathway between the copper ions with J/k = 6.91(3) K. Short Cl...Cl contacts (3.67-3.90 angstoms) lead to very weak antiferromagnetic coupling between the ferromagnetically coupled trimers.     

Halogen exchange and scrambling between C-X and M-X' bonds in copper, nickel, and cobalt complexes of 6,6'-bis(bromo/chloromethyl)-2,2'-bipyridine. structural, electrochemical, and photochemical studies

The synthesis, reactivities, spectroscopic, electrochemical, and structural studies of copper(I), copper(II), nickel(II), and cobalt(II) complexes of 6,6'-bis(bromomethyl)-2,2'-bipyridine (bpy-Br2) and 6,6'-bis(chloromethyl)-2,2'-bipyridine (bpy-Cl2) have been reported. The copper(I) complex [CuI(bpy-Br2)2](ClO4) (1) has been obtained in two crystallographic modifications, in which the coordination geometry of the metal center has the D2d symmetry. The reaction between CuCl2.2H2O and bpy-Br2 has been followed spectrophotometrically at 45 degrees C over a period of 7 h, and a mechanism for the intramolecular halogen exchange and scrambling in the initially formed compound [CuII(bpy-Br2)Cl2] (5) has been proposed. Depending upon the reaction conditions, several halogen-exchanged products, namely [CuII(bpy-Br1.86Cl0.14)(Cl1.89Br0.11)] (2), [CuII(bpy-Br1.81Cl0.19)(Cl1.70Br0.30)(H2O)] (3), and [CuII(bpy-Br0.63Cl1.37)(Cl0.54Br1.46)] (4), have been isolated in crystalline form. The reaction between bpy-Cl2 and CuCl2.2H2O provides [CuII(bpy-Cl2)Cl2] (7) and [CuII(bpy-Cl2)Cl2(H2O)] (8), whereas CoCl2.6H2O and NiCl2.6H20 on reaction with bpy-Br2 under boiling condition produce [CoII(bpy-Br0.5Cl1.5)(ClBr)] (11) and [NiII(bpy-Br0.46Cl1.54)(Cl0.73Br1.27)(H2O)] (12), respectively. The X-ray structures determined for the 4-coordinate compounds 2, 4, and 7 show flattened tetrahedral geometry for the metal center with the D2 symmetry. Both 5-coordinate compounds 3 and 12 have square pyramidal geometry, and whereas the nickel(II) complex 12 has near-perfect geometry (tau = 0.015), considerable distortion is observed for the copper(II) complex 3 (tau = 0.25). Complexes [CuII(bpy-Cl2)Br2] (6) and [CuII(bpy-Br2)Br2] under boiling condition undergo photoreduction to produce the dimeric copper(I) complexes [{CuI(bpy-Cl1.30Br0.70)(mu-Br)}2](9) and [{CuI(bpy-Br2)(mu-Br)}2] (10), respectively. The fact that the photoreduction of [CuII(bpy-Cl2)Br2] (6) and [CuII(bpy-Br2)Br2] do not take place in absence of light has been established by spectrophotometric measurements. The crystal structures of 9 and 10 have been determined. The electrochemical behavior of all the copper complexes 1-10 has been studied in acetonitrile and dichloromethane. The E1/2 values for the CuI/CuII redox couples show strong solvent dependence and for a given system the E1/2 value is more positive in dichloromethane relative to that in acetonitrile. For the compounds [CuII(bpy-Br2-xClx)(Cl2-yBry)] (x = 0-2, y = 0-2), the E1/2 values become more positive with the increase of y value.     

Density functional study of adenine tetrads with N6-H6...N3 hydrogen bonds

The structure and energy of A-tetrads with N6-H6...N3 H-bonds was studied using B3LYP and BH&H density functional theory. The planar A-tetrad with C(4h) symmetry is more stable than the nonplanar structures at C4 and S4 symmetry. This structure corresponds to a local energy minimum. The energies of the structures with N6-H6...N1 and N6-H6...N7 H-bonds studied previously are of similar magnitude. Structures of A-tetrad complexes with sodium and potassium were most stable at S4 symmetry, and similarly, sandwich complexes consisting of two tetrads and a single cation were most stable at S8 symmetry. Relative energies of sandwich complexes with different symmetries obtained with the B3LYP and BH&H methods were quite different. BH&H overestimates the interaction energies between hydrogen-bonded neighbor bases relative to B3LYP.     

Planar pentacoordinate carbon in CAl5(+): a global minimum

We report evidence for the first global-minimum structure having a planar pentacoordinate carbon. High-level ab initio computations and quantum molecular dynamics simulations at 300 and 400 K reveal that the most stable CAl5(+) isomer has D5h symmetry and is approximately 3.80 kcal/mol lower in energy than the second most stable alternative. The latter has a nonplanar structure based on a tetrahedral CAl4 moiety. The unexpectedly high proclivity for two-dimensional chemical bonding of the carbon in D5h CAl5(+), the robust thermal stability indicated computationally, and its mass spectrometric detection suggest that experimental characterization of this planar pentacoordinate carbon cation at room temperature is a likely prospect.     

Electron spin resonance and magnetic studies on some copper(II) azobarbituric and azothiobarbituric acid complexes

Electron spin resonance and magnetic susceptibility on some copper(II) complexes prepared from phenylazobarbituric and phenylazothiobarbituric acid compounds containing 2,5-dichloro and 2,5-dimethyl groups were discussed. The thio complexes exist in dimer-monomer mixture. The corresponding copper(II) complexes of the oxygen homologous failed to exhibit association. Singlet-triplet separation values equal to -321 and -263 cm(-1) for the 2,5-dimethyl and 2,5-dichloro complexes, respectively, of the thio series. An empirical measure of the amount of tetrahedral deformation based on the values of g||/A|| assigned the square-planar geometry of the dimethyl-oxygen complex while the other complexes are with tetrahedral planar geometries. The effect of temperature on the ESR data was discussed. The diamagnetic properties of the complexes derived from 2,5-dichloro and 2,5-dimethyl thiobarbituric acid suggested the formation of Cu(I) complexes.     

The unexpected versatility of P(4)S(3) as a building block in polymeric copper halide networks: 2,3-P, 1,2,3-P and all-P coordination

Layering solutions of P(4)S(3) in CH(2)Cl(2) with solutions of CuCl or CuI in CH(3)CN gives the coordination polymers (P(4)S(3))(3)(CuCl)(7) (1), (P(4)S(3))(2)(CuCl)(3) (2), (P(4)S(3))(CuI) (3) and (P(4)S(3))(CuI)(3) (4), respectively, after slow diffusion. The yellow compounds were characterised by elemental analysis, (31)P magic-angle spinning (MAS) NMR spectroscopy and single-crystal X-ray crystallography. The solid-state structures demonstrate the unexpected ligand versatility of the P(4)S(3) molecule, which interacts through two, three, or even all of the phosphorus atoms with copper according to the nature of the copper halide. Compound 1 has a three-dimensional network in which linear and cylindrical infinite CuCl subunits coexist with diatomic CuCl building blocks. For the first time, all four P atoms of the P(4)S(3) cage are involved in coordination with metal atoms. The 3D structure of 2 contains stacks of P(4)S(3) that are interconnected by slightly undulated and planar [CuCl](n) ribbons. Compound 3 is a one-dimensional polymer composed of alternating (CuI)(2) rings and P(4)S(3) bridges. The structure of 4 consists of undulated [CuI](n) layers in which the P(4)S(3) cage functions as a bridge within the layer, as well as a spacer between the layers. The (31)P MAS NMR spectra obtained are in good agreement with the solid-state structures obtained crystallographically. Thus, analytically pure 3 and 4 show singlet peaks that correspond to uncoordinated P and quartets owing to coupling with (63)Cu and (65)Cu, respectively, whereas that of 1 contains quartets according to all-P coordination. The spectrum of 2 was obtained from a sample that still contained 40 % of 1.     

Monodentate coordination of N-[di(phenyl/ethyl)carbamothioyl]benzamide ligands: synthesis, crystal structure and catalytic oxidation property of Cu(I) complexes

New four-coordinated tetrahedral copper(I) complexes have been synthesized from the reactions between [CuCl(2)(PPh(3))(2)] and N-(diphenylcarbamothioyl)benzamide (HL1) or N-(diethylcarbamothioyl)benzamide (HL2) in benzene. These complexes have been characterized by elemental analyses, IR, UV/Vis, (1)H, (13)C and (31)P NMR spectroscopy. The molecular structure of both the complexes, [CuCl(HL1)(2)(PPh(3))] (1) and [CuCl(HL2)(PPh(3))(2)] (2) were determined by single-crystal X-ray diffraction, which reveals distorted tetrahedral geometry around each Cu(I) ion. The combination of 2 (0.005 mmol) with hydrogen peroxide (2.5 mmol) in acetonitrile is found to be an active catalyst for the oxidation of primary and secondary alcohols (0.5 mmol) to their corresponding acids and ketones, respectively, at room temperature.     

Effect of terminal N-substitution in 2-oxo-1,2-dihydroquinoline-3-carbaldehyde thiosemicarbazones on the mode of coordination, structure, interaction with protein, radical scavenging and cytotoxic activity of copper(II) complexes

Four 2-oxo-1,2-dihydroquinoline-3-carbaldehyde N-substituted thiosemicarbazone ligands (H(2)-OQtsc-R, where R = H, Me, Et or Ph) and their corresponding new copper(II) complexes [CuCl(2)(H(2)-OQtsc-H)]·2H(2)O (1), [CuCl(2)(H(2)-OQtsc-Me)]·2H(2)O (2), [CuCl(2)(H(2)-OQtsc-Et)(CH(3)OH)]Cl (3) and [CuCl(H-OQtsc-Ph)]·CH(3)OH (4) have been synthesized in order to correlate the effect of terminal N-substitution on coordination behaviour, structure and biological activity. Single crystal X-ray diffraction studies revealed that the complexes 1, 2 and 3 have square pyramidal geometry around the central metal ion. In the complexes 1 and 2, the copper ion is coordinated by the ligand with ONS donor atoms, one chloride ion in apical position and the other chloride in the basal plane. Complex 3 consists of [CuCl(2)(H(2)-OQtsc-Et)(CH(3)OH)](+) cation and a chloride as counter ion. The copper ion is coordinated by the ligand with ONS donor atoms and by one chloride ion in the basal plane. One methanol molecule is bonded through its neutral oxygen in the apical position. Complex 4 is square planar with the ligand coordinating through uni-negative tridentate ONS(-) and by one chloride ion in the basal plane. The binding of complexes with lysozyme protein was carried out by fluorescence spectroscopy. Investigations of antioxidation properties showed that all the copper(II) complexes have strong radical scavenging properties. The cytotoxicity of the complexes 3 and 4 against NIH 3T3 and HeLa cell lines showed that synergy between the metal and ligands results in a significant enhancement in the cell death with IC(50) of ~10-40 μM. A size dependence of substitution at terminal N in the thiosemicarbazones on the biological activities of the complexes has been observed.     

Correlation between DFT calculated and X-ray structures from CSD,for Cu(II) and Cu(I) coordination spheres when coordinated to four acyclic amine ligands. A reconsideration of copper(II) planarity

The Cambridge Crystallographic Database (CSD) shows [Cu^IIL₄]²⁺ complexes, L = acyclic amine, fitting well with theoretically calculated structures to describe a planar-to-flat tetrahedral transformation pathway. Statistically, the Cu^II “planar” coordination sphere shows two distinct sets of trans N–Cu–N bond angles, 180° and near 150°, with the latter somewhat energetically favored according to DFT results. The planar structure is not confirmed theoretically when an example of these molecules in the CSD is geometrically minimized, suggesting that crystallographic or packing forces help to generate the planar structure in the crystal. Results of energy calculations from DFT seem to explain this feature. Less planar and more tetrahedral examples in the CSD are also found and compare well with theoretically converged related molecules. Trans N–Cu–N bond angles near 130° seem feasible for both Cu^I and Cu^II coordination spheres. These copper complexes having the copper coordination sphere in a less tetrahedral geometry are suggested as potential alternative models for blue proteins, and they deserve further exploration.     

Tetra-, di-, and mononuclear copper(I) complexes containing (S,S)-iPr-pybox and (R,R)-Ph-pybox ligands

Tetranuclear [Cu4I4{(S,S)-iPr-pybox}2] (1) and dinuclear [Cu2Cl-{(S,S)-iPr-pybox}2][CuCl2] (2) copper(I) complexes have been synthesized by reaction of iPr-pybox with CuI and CuCl, respectively. Furthermore, dinuclear [Cu2(R-pybox)2][PF6]2 [R-pybox = (R,R)-Ph-pybox (3), (S,S)-iPr-pybox (4)] and mononuclear complexes [Cu(R-pybox)2][PF6] [R-pybox = (R,R)-Ph-pybox (5), (S,S)-iPr-pybox (6)] have been prepared by reaction of [Cu(MeCN)4][PF6] and the corresponding pybox. The structures of complexes 1-3 have been determined by X-ray diffraction analyses.     

A comparison of structure and stability between the group 11 halide tetramers M4X4 (M = Cu, Ag, or Au; X = F, Cl, Br, or I) and the group 11 chloride and bromide phosphanes (XMPH3)4

The tetramers of the group 11 (I) halides, M(4)X(4) (M = Cu, Ag, or Au; X = F, Cl, Br, or I), and corresponding group 11 (I) phosphanes, chloride and bromide (XMPH(3))(4) (X = Cl or Br), are investigated by the density functional theory. All coinage metal(I) halide tetramers adopt squarelike ring structures with an out-of-plane distorted (butterfly) D(2d) symmetry. These structures are much lower in energy than the more compact cubelike T(d) arrangements, which maximize dipole-dipole interactions and more closely resemble the solid-state structures of the copper and silver halides. Phosphine coordination completely changes the structures of these M(4)X(4) clusters. The copper(I) and silver(I) phosphane chloride and bromide tetramers adopt a heterocubane structure, slightly preferred over a step (ladder-type)-cluster structure well-known in the coordination chemistry of such compounds. In stark contrast, gold(I) phosphane chloride and bromide tetramers prefer assemblies of linear XAuPH(3) units with direct gold-gold contacts, resulting in a square planar, centered trigonal planar, or tetrahedral gold core.     

Electronic structures of zinc and palladium tetraazaporphyrin derivatives controlled by fused benzo rings

Zinc and palladium tetracyclic aromatic complexes lying structurally between tetraazaporphyrin (TAP) and phthalocyanine (Pc), that is, monobenzo-, adjacently dibenzo-, oppositely dibenzo-, and tribenzo-fused TAPs, have been prepared, and their electronic structures investigated by electronic absorption, magnetic circular dichroism (MCD), fluorescence, phosphorescence, and time-resolved electron paramagnetic resonance (TREPR) spectroscopy, as well as cyclic voltammetry. The last-named indicated that the first oxidation potentials shift to more negative values with increasing number of the fused benzo rings, but also suggested that the first reduction potential apparently has no correlation with the size and symmetry of the pi-conjugated systems. However, this latter behavior is reasonably interpreted by the finding that the effect of the fused benzo rings on destabilization of the LUMO depends on the orbital to which they are fused (i.e., whether it is an egx or egy orbital), since the LUMOs of TAP complexes are degenerate with D4h symmetry. The energy splitting of the LUMOs, that is, DeltaLUMO, was evaluated experimentally for the first time by analyzing the relationship between the first reduction potential and the size and shape of the pi-conjugated system. Electronic absorption and MCD measurements indicate that the lowest excited singlet states are split in the case of the low-symmetry TAP derivatives, although these excited states are degenerate for Pc and TAP with D4h symmetry. These energy splittings DeltaE(SS) correlate well with the DeltaLUMO values. To investigate the electronic structures in the lowest excited triplet state, zero-field splitting (zfs) was analyzed by time-resolved EPR (TREPR) spectroscopy. The energy splitting in the lowest excited triplet state, DeltaE(TT) was quantitatively evaluated from the temperature dependence of the zfs or spin-orbit coupling of the Pd complexes. Consequently, it is demonstrated that DeltaLUMO, DeltaE(SS), and DeltaE(TT) values exhibiting a mutually good relationship can be determined experimentally.     

Honeycombs, herringbones and brick-walls; three-fold guest-dependent variation in copper trimesate complexes bearing sulfimide ligands

Reaction of a solution of CuSO(4) and S,S'-diphenylsulfimide, Ph(2)SNH 1, with sodium salts of trimesic acid (H(3)tma) in MeOH gives the 2-D coordination network [Cu(3)(Ph(2)SNH)(6)(tma)(2)] in which each trimesate is bound to three copper centres. Addition of other solvents to the reaction mixture causes a change in the shape of the network. By this route, three forms have been prepared and characterised by X-ray crystallography. These include the known honeycomb, 2, and brick-wall, 3, motifs and a herringbone, 4, arrangement which is novel for transition metal-containing trimesate complexes. Key to the supramolecular isomerism observed is the ability of 1 to facilitate structural isomerism at copper(II) centres. In contrast to 2 in which the copper centres are square planar, 4 is analogous to an inter-allogon, with both planar and tetrahedral copper centres. Also prepared is a related complex which is composed of discrete units of three copper centres. These are further linked into a 2-D network by hydrogen bonds.     

Dicyclobuta[de,ij]naphthalene and dicyclopenta[cd,gh]pentalene: a theoretical study

The structures, energetics, and aromatic character of dicyclobuta[de,ij]naphthalene, 1, dicyclopenta[cd,gh]pentalene, 2, dihydrodicyclobuta[de,ij]naphthalene, 3, and dihydrocyclopenta[cd,gh]pentalene, 4, have been examined at the B3LYP/6-311++G//B3LYP/6-31G level of theory. All molecules are bowl-shaped, and the pentalene isomers, 2 and 4, are most stable. A comparison with other C(12)H(6) and C(12)H(8) isomers indicates that 2 is approximately 25 kcal/mol less stable than 1,5,9-tridehydro[12]annulene and 4 is approximately 100 kcal/mol higher in energy than acenaphthylene, both of which are synthetically accessible. The transition state structure for bowl-to-bowl inversion of 1 is planar (D(2)(h)()) and lies 30.9 kcal/mol higher in energy than the ground state; the transition state for inversion of 2 is C(2)(h)() and lies 46.6 kcal/mol higher in energy. Symmetry considerations, bond length alternations, and NICS values (a magnetic criterion) all indicate that the ground states of 1, 3, and 4 are very aromatic; however, HOMA values (a measure of bond delocalization) indicate that 3S and 4S are aromatic but that 1S is less so. NICS values for the ground state of 2 strongly indicate aromaticity; however, bond localization, symmetry, and HOMA values argue otherwise.     

不同焙烧温度对Cu/γ-Al2O3催化剂铜物种结构的影响

用XRD和EXAFS研究了焙烧温度(35─1000 ℃)和负载量(质量分数为5－15％Cu)对于Cu/γ-Al_2O_3催化剂铜物种的影响。低于700 ℃焙烧时,铜以高分散状态存在。根据Cu~(2+)同时占据八面体(Oh)和四面体(Td)两种位置,对第一壳层的Cu-O配位峰进行了拟合。结果显示,随着焙烧温度增加,铜氧配位距离逐渐增加,Cu~(2+)(Oh)/Cu~(2+)(Td)的比例降低,并且Cu~(2+)(Oh)与氧的平均配位数从5.1变成6.0．这表明Cu~(2+)离子由Oh位向Td位迁移,同时向内层扩散使表面配位不饱和的氧缺顶畸变八面体部分变为配位饱和的对称八面体。900 ℃和更高温度的焙烧,使铜离子扩散进载体相形成CuAl_2O_4。     

Copper(II) complexes of 4-chloro,3-methyl,5-phenylisoxazole

4-chloro,3-methyl,5-phenylisoxazole copper(II) complexes of the type Cu(L)X₂(X = Cl, Br, NO₃) and Cu(L)₂(ClO₄)₂ have been prepared and studied by the IR, electronic, paramagnetic resonance spectroscopy and molar conductivity values. The ligand acts as monodentate N-bonded except to the nitrate derivative where this behaves as bridging bidentate. The halide complexes are tetrahedral, while the nitrate and perchlorate derivatives are square planar.     

Thermal, spectroscopic, and solvent influence studies on mixed-ligand copper(II) complexes containing the bulky ligand: Bis[N-(p-tolyl)imino]acenaphthene

Four mixed-ligand copper(II) complexes containing the rigid bidentate nitrogen ligand bis[N-(p-tolyl)imino]acenaphthene (abb. p-Tol-BIAN) ligand are reported. These complexes, namely [Cu(p-Tol-BIAN)(2)](ClO(4))(2)1, [Cu(p-Tol-BIAN)(acac)](ClO(4)) 2, [Cu(p-Tol-BIAN)Cl(2)] 3 and [Cu(p-Tol-BIAN)(AcOH)(2)](ClO(4))(2)4 (where acac, acetylacetonate and AcOH, acetic acid) have been prepared and characterized by elemental analysis, spectroscopic, magnetic and molar conductance measurements. ESR spectra suggest a square planar geometry for complexes 1 and 2. In complexes 3 and 4, a distorted tetrahedral arrangement around copper(II) centre was suggested. Solvatochromic behavior of all studied complexes indicates strong solvatochromism of their solutions. The observed solvatochromism is mainly due to the solute-solvent interaction between the chelate cation and the solvent molecules. Thermal properties and decomposition kinetics of all complexes are investigated. The kinetic parameters (E, A, Delta H, Delta S and Delta G) of all thermal decomposition stages have been calculated using the Coats-Redfern and other standard equations.     

Synthesis and characterization of iron(III), manganese(II), cobalt(II), nickel(II), copper(II) and zinc(II) complexes of salicylidene-N-anilinoacetohydrazone (H2L1) and 2-hydroxy-1-naphthylidene-N-anilinoacetohydrazone (H2L2)

Salicylidene-N-anilinoacetohydrazone (H(2)L(1)) and 2-hydroxy-1-naphthylidene-N-anilinoacetohydrazone (H(2)L(2)) and their iron(III), manganese(II), cobalt(II), nickel(II), copper(II) and zinc(II) complexes have been synthesized and characterized by IR, electronic spectra, molar conductivities, magnetic susceptibilities and ESR. Mononuclear complexes are formed with molar ratios of 1:1, 1:2 and 1:3 (M:L). The IR studies reveal various modes of chelation. The electronic absorption spectra and magnetic susceptibility measurements show that the iron(III), nickel(II) and cobalt(II) complexes of H(2)L(1) have octahedral geometry. While the cobalt(II) complexes of H(2)L(2) were separated as tetrahedral structure. The copper(II) complexes have square planar stereochemistry. The ESR parameters of the copper(II) complexes at room temperature were calculated. The g values for copper(II) complexes proved that the Cu-O and Cu-N bonds are of high covalency.     

Chirality and Stereogenicity of Square‐Planar Complexes

Square‐planar complexes with achiral and chiral ligands have been enumerated exhaustively under the point‐group D _4h and under the symmetry group S ^[4] of degree 4, where they have been classified in terms of their symmetries and permutabilities. Thereby, their stereochemical properties and relationships have been discussed in detail. In particular, equivalency under point‐group symmetry (e.g., enantiomeric relationships for chiral complexes and prochirality for achiral complexes) and that under permutation‐group symmetry (e.g., proper and improper permutations, stereogenic and astereogenic groups, and enantiostereogenic and diastereogenic groups) have been characterized to give a systematic format for stereochemistry and stereoisomerism.     

Syntheses and ligand interconversions of copper(II) derivatives of the metalloligand [Pt2(mu-S)2(PPh3)4

The reactivity of the metalloligand [Pt2(micro-S)2(PPh3)4] towards a variety of copper(II)-ligand systems has been studied. Reaction of [Pt2(mu-S)2(PPh3)4] with copper(II) halide complexes [CuCl2L](L = 2,2'-bipyridine and 1,10-phenanthroline) gave trinuclear dicationic products [Pt2(mu-S)2(PPh3)4CuL]2+, and the 8-hydroxyquinolinate (hq) complex [Cu(hq)2] gave [Pt2(mu-S)2(PPh3)4Cu(hq)]+, isolated as their BPh4- or PF6- salts. Related cationic complexes with other ancillary amine ligands (1,2-diaminoethane, 1,2-diaminopropane, 1,2-diaminocyclohexane) were obtained by reactions of [Pt2(mu-S)2(PPh3)4] with CuCl2 and the amine. In contrast, reaction of [Pt2(mu-S)2(PPh3)4] with CuCl2 and NH3 in methanol gave the intensely blue methoxy-bridged dicopper complex [{Pt(2)(mu-S)2(PPh3)4Cu(OMe)}2]2+, isolated as its hexafluorophosphate salt. Copper beta-diketonate complexes reacted with [Pt2(mu-S)2(PPh3)4] giving [Pt2(mu-S)2(PPh3)4Cu(beta-diketonate)]+PF6- complexes, with the CH3COCHCOCH3(acac) and CF3COCHCO(2-thienyl)(tta) derivatives characterised by X-ray structure determinations. The local Cu(II) environment ranges from distorted square-planar to an intermediate form of square-planar and tetrahedral. The beta-diketonate derivatives show varying stability towards methanolysis, giving [{Pt2(mu-S)2(PPh3)4Cu(OMe)}2]2+.