Cluster—cracking Reaction,a New Method to Synthesize Unsymmetrical Dithiolate Complexes for the Study of Third—Order Nonlinear Optical Properties

A new coluster-cracking method to synthesize dithiolate metal complexes was reported and four unsymmetric complexes with formula(Me4N)2[M(Ln)(SPh)2](M=Cd and Zn,L1=dmit=1,3-dithiole-2-thione4-5,dithiolate,L2=dmid=1,3-dithiole-2-one-4,5-dithiolate,SPh=thiophenolate)(1-4)were characterized by elemental analysis,IR,UV NMR spectra and so on.The advantages of this method are summarized in two aspects:(1) the preparation is very convenient;(2) the reaction usually completed giving the product with high pruity.The crystal structure of 1 showed that the bond distances of Cd(Ⅱ）to the sulfur of the thiophenolate group are shorter than those of Cd(Ⅱ）to the sulfur of dmit,so that the thiophenolate group does not be replaced in the reaction and thmixed ligand complexes are the dominant produxts.The dmit complexes showed well third-order NLO properties,but not of the dmid complexes,although dmid is an analogue to dmit.     

Redox Multifunctionality in a Series of PtII Dithiolene Complexes of a Tetrathiafulvalene‐Based Diphosphine Ligand

The redox‐active and chelating diphosphine, 3,4‐dimethyl‐3′,4′‐bis(diphenylphosphino)‐tetrathiafulvalene, denoted as P2 , is engaged in a series of platinum complexes, [(P2)Pt(dithiolene)], with different dithiolate ligands, such as 1,2‐benzenedithiolate (bdt), 1,3‐dithiole‐2‐thione‐4,5‐dithiolate (dmit), and 5,6‐dihydro‐1,4‐dithiin‐2,3‐dithiolate (dddt). The complexes are structurally characterized by X‐ray diffraction, together with a model compound derived from bis(diphenylphosphino)ethane, namely, [(dppe)Pt(dddt)] . Four successive reversible electron‐transfer processes are found for the [(P2)Pt(dddt)] complex, associated with the two covalently linked but electronically uncoupled electrophores, that is, the TTF core and the platinum dithiolene moiety. The assignments of the different redox processes to either one or the other electrophore is made thanks to the electrochemical properties of the model compound [(dppe)Pt(dddt)] lacking the TTF redox core, and with the help of theoretical calculations (DFT) to understand the nature and energy of the frontier orbitals of the [(P2)Pt(dithiolene)] complexes in their different oxidation states. The first oxidation of the highly electron‐rich [(P2)Pt(dddt)] complex can be unambiguously assigned to the redox process affecting the Pt(dddt) moiety rather than the TTF core, a rare example in the coordination chemistry of tetrathiafulvalenes acting as ligands.     

Metallorganische Lewis-Säuren. L. Addition von Pentacarbonylrhenium- und Triphenylphosphangold-Kationen an anionische Dithiolato-Metall-Komplexe als S-Nukleophile

Organometallic Lewis Acids. L. Addition of Pentacarbonylrhenium and Triphenylphosphinegold Cations to Anionic Dithiolato Metal Complexes as S-Nucleophiles The organometallic Lewis Acids Ph₃PAuNO₃ ( 1 ) and (CO)₅ReFBF₃ ( 2 ) react with the dithiolato metal complexes (Bu₄N)₂[M(mnt)₂] (mnt = m aleo n itrildi t hiolato, M = Ni, Cu, Pt, Zn) and (Bu₄N)₂[Zn(dmit)₂] (dmit = d i m ercapto i sotri t hiono) to give the complexes (Ph₃PAu)₂mnt ( 3 ), (Bu₄N)[Ph₃PAu(mnt)] ( 4 ), (Ph₃PAu)₂Pt(mnt)₂ ( 5 ), (Ph₃PAu)₂dmit ( 10 ) and [(CO)₅Re]₂Ni(mnt)₂ ( 6 ), (Bu₄N){[(CO)₅Re]M(mnt)₂} (M = Ni, Pt, 7, 8 ), [(CO)₅Re]₂(mnt)₂ ( 9 ) and [(CO)₅Re]₂Ni(dmit)₂ ( 11 ), respectively. The compounds 3, 4 and 5 have been characterized by x-ray structural analysis. In 4 the chelate ligand is symmetrically coordinated to the Au^I atom. Weak Au? Au (d_{Au? Au} = 309 pm) interactions lead to the formation of chains in the crystal of 3 . The trans-anti configuration in 5 can also be assumed for the complexes 6 and 11 for sterical reasons. Compound 1 reacts with K₂[M(dto)₂] (dto = d i t hio o xalato, M = Pd, Pt) to give the expected bis(triphenylphosphinegold) adducts 12 and 13 . Complex 2 , however, affords with dithiooxalato metal dianions the compound [(CO)₅Re]₂(dto)₂ ( 14 ) as final product. (Ph₃PAu)₂dto ( 15 ) is obtained by reaction of 1 with K₂dto. [(CO)₅Re]₂FeNO(dto)₂ ( 16 ) can be isolated as an unstable adduct from the reaction of 2 with [Fe(NO)(dto)₂]^2? Re(CO)₅⁺ and Ph₃PAu⁺ can be added to the bridging S atoms of [(ON)₂Fe(μ-S)₂Fe(NO)₂]^2? to give 17 and 18     

Synthesis and Crystal Structures of Group 10 Metal Bis(dithiolate) Complexes Constructed by 2,3-Naphtho-15-Crown-5 or 2,3-Naphtho-18-Crown-6

Five novel 2,3-naphtho crown ether group 10 metal bis(dithiolate) complexes, [Na(N15C5)₂]₂[Pd(mnt)₂] (1), [Na(N15C5)]₂[Pd(i-mnt)₂] (2) and [K(N18C6)]₂[M(i-mnt)₂] (3 5) (where mnt = 1,2-dicyanoethylene-1,2-dithiolate, i-mnt = 1,1-dicyanoethylene-2,2-dithiolate and M = Ni, Pd, Pt for complexes 3–5, respectively), have been synthesized and characterized by elemental analysis, FT-IR, UV–Visible spectra and single crystal X-ray diffraction. X-ray diffraction analyses reveal that complexes 1 and 2 have different structural features while complexes 3–5 are structurally isomorphous. Complex 1 consists of two [Na(N15C5)₂]⁺ sandwich complex cations and one [Pd(mnt)₂]²⁻ anion, affording a zero-dimensional structure. For 2, the [Na(N15C5)]⁺ mono-capped complex cations act as the bridges linking the [Pd(i-mnt)₂]²⁻ anions into a 1D infinite chain through Na–N interactions and SȮFC and SȮFπ interactions are observed in the resulting chain. Complexes 3–5 all consist of two [K(N18C6)]⁺ complex cations and one [M(i-mnt)₂]²⁻ (M = Ni, Pd or Pt) anion and the complex molecules are linked into␣1D␣chains by the bridging K–O(ether) interactions between the adjacent [K(N18C6)]⁺ units. What’s novel is that the resulting chains are assembled into novel 2D networks through interchain π–π stacking interactions between the neighboring naphthylene moieties of N18C6. The stack model of naphthylene group in complexes 3–5 is discussed.     

Synthesis, characterization, and crystal structure of the Pd(phen)(bdt) complex. A DFT and TDDFT study of its ground electronic and excited states compared to those of analogous complexes

The synthesis and characterization of Pd(phen)(bdt) (1) (phen = 1,10-phenanthroline, bdt = 1,2-benzenedithiolate) is presented. 1 crystallizes in the monoclinic space group P2(1)/c, alpha = 11.281(4) A, b = 20.498(8) A, c = 8.374(3) A, beta = 90.234(8), V = 1936.5(13) A(3), Z = 4, and is isostructural with its previously reported related complexes. The ground and low lying excited electronic states in 1 and in the related complexes Pd(bpy)(bdt) (2), Pt(bpy)(bdt) (3), Pt(bpy)(mnt) (4), and Pt(bpy)(edt) (5) [where bpy = 2,2'-bipyridine, edt = ethylene-1,2-dithiolate, and mnt = maleonitriledithiolate] are studied using density functional theory techniques. The electronic properties of 1-5 are studied using the B3LYP functional. Optimized geometries are compared to experimentally observed structures. Time dependent density functional theory (TDDFT) is employed to investigate the excited singlet and triplet states. The calculated energies of the lowest singlet state and the lowest triplet state in all five complexes are in considerable agreement with experimental data. It is shown that variation of both metal and dithiolate-ligand going from 1 and 2 to 3, 4, and 5 has a substantial impact on the spectroscopic and excited-state properties, indicating at the same time the mixed metal/dithiolate character of the HOMO orbital. All the low-lying transitions are categorized as MMLL'CT transitions. The emissive state of all complexes is assigned as a triplet dithiolate/metal to diimine charge transfer with differences in the structures of the emissions resulting from differences in the pi dithiolate orbital of the mnt, bdt, and edt as well as from differences in metal.     

Synthesis, structure, and electroconductivity of new radical cation salt [Pd(dddt)2]2GaBr4

A new radical cation salt based on the dithiolate complex Pd(dddt)₂ (dddt=5,6-dihydro-1,4-dithiine-2,3-dithiolate) with the tetrahedral anion [GaBr₄]^? was synthesized. The crystal and molecular structure was determined by XRD analysis. The crystal structure of the salt contains Pd(dddt)₂ cation layers alternating with layers of [GaBr₄]^? anions along thec axis of the unit cell. The cation layers contain stacks of Pd(dddt)₂, with a Pd...Pd distance of 3.011 Å. The electroconductivity of [Pd(dddt)₂]₂GaBr₄, single crystals at room temperature is 0.25 Ohm^?1 cm^?1 and decreases with temperature decrease, the activation energy beingE _a=0.66 eV.     

Syntheses and characterization of heterobimetallic complexes (dppf)Pt(dithiolate) (dppf: bis(diphenylphosphino)ferrocene); X-ray crystal structures of (dppf)PtL where L=dmit,phdt and i-mnt

Heterobimetallic complexes of the type (dppf)PtL (dppf=1,1′-bis(diphenylphosphino)ferrocene; L=dmit (1,3-dithiole-2-thione-4,5-dithiolate), dddt (5,6-dihydro-1,4-dithiin-2,3-dithiolate), phdt (6-hydro-5-phenyl-1,4-dithiin-2,3-dithiolate), dphdt (5,6-diphenyl-1,4-dithiin-2,3-dithiolate), mtdt (1,2-bis(methylthio)ethylene-1,2-dithiolate), i-mnt (2,2-dicyano-1,1-ethylenedithiolate)) have been synthesized and studied by a high-resolution FAB-MS, cyclic voltammetry and ³¹P NMR. (Dppf)Pt(i-mnt) exhibits one reversible redox peak at E_1/2=1.225 V and a strong Pt–P coupling constant (J_Pt–P=3237 Hz) due to the electron-accepting property of i-mnt ligand. On the contrary, (dppf)Pt(mtdt) shows three reversible redox peaks corresponding to [dppf]^0/+ (E_1/2¹=0.470 V), [Pt(mtdt)]^0/+ (E_1/2²=1.050 V) and [Pt(mtdt)]^+/2+ (E_1/2³=1.405 V) processes and a weak Pt–P coupling constant (J_Pt–P=2962 Hz) due to relatively strong electron-donor property of mtdt ligand. X-ray structural analyses were performed for the three complexes: (dppf)PtL where L=dmit, phdt and i-mnt. The P₂PtS₂ core shows a distorted square planar geometry for the three complexes with P(1)–Pt–P(2) bite angle being larger than 96°. The S(1)–Pt–S(2) bite angle of the i-mnt complex is the smallest (74.42°) because of the formation of the four-membered ring.     

Synthesis,structures and magnetic properties of nickel bis (dithiolene) complexes with [Fe(qsal)2]+

Two new compounds containing the possible Fe(III) spin-crossover cation, [Fe(qsal)₂]⁺ (qsalH = N-(8-quinolyl)salicylaldimine), and nickel bis(dithiolene) anions have been synthesized. Both are 1 : 1 salts [Fe(qsal)₂][Ni(dddt)₂] · CH₃CN · CH₃OH (1) and [Fe(qsal)₂][Ni(pddt)₂] (2) (dddt = 5,6-dihydro-1,4-dithiin-2,3-dithiolate; pddt = 6,7-dihydro-5H-1,4-dithiepin-2,3-dithiolate). They have been characterized by X-ray crystal structure determination, elemental analysis, UV-Vis spectra and magnetic susceptibility measurements. The UV–Vis spectra are dominated by [Ni(L)₂]^? (1, L = dddt; 2, L = pddt). Magnetic studies show antiferromagnetic interaction in 1 from intermolecular S···S contacts and π–π stacking interactions, while the antiferromagnetic interaction in 2 is very weak.     

两种马来二腈基二硫烯镍(Ⅲ)近红外吸收配合物的结构、磁和电化学性质

合成并表征了两种新的离子对化合物(BMIB)[(Ni(mnt)2]2(1)和(BMIO)[(Ni(mnt)2)]2(2)(其中mnt2-=马来二氰基二硫烯,BMIB=1,4-bis(1-methylimidazolium)butane,BMIO=1,8-bis(1-methylimidazolium)octane)。在化合物1中,[Ni(mnt)2]-阴离子排列形成阴离子三聚体以及与阳离子交替排列形成阴、阳离子混合柱。化合物2的堆积结构与化合物1不同,阴、阳离子堆积成非等间距的阴、阳离子柱。化合物1和2分别在861和857 nm近红外波段处出现较强的近红外吸收。电化学性质研究结果表明,2个化合物均出现了两对不可逆的电化学氧化/还原过程,且平衡阳离子的烷基链长显著影响化合物的氧化、还原电极电势。变温磁化率测量表明,在2～400 K温度范围内,化合物1表现出弱的顺磁性质,变温摩尔磁化率遵循简单的Curie-Weiss定律。化合物2表现出低维反铁磁交换自旋体系磁化率特征。     

Structure of the neutral metal complex Pt(dddt)2

A neutral metal complex, [Pt(dddt)₂]° (1), has been obtained by oxidation of the [Pt(dddt)₂]^– anion with excess (Bu₄N)AuBr₄ in nitrobenzene. Crystallographic data for 1a=17.854(9) Å,b=18.409(9) Å,c=4.717(5) Å, =68.83(2)°, space group P2₁/n,Z=4,d _calc=2.55 g/cm³. In1 two independent centrosymmetric [Pt(dddt)₂]° molecules are packed in stacks that form layers parallel to the (110) plane. The molecules of1 in the layers have shortened S...S contacts 3.491(9) Å, and 3.594(10) Å. The average bond lengths Pt-S 2.242(7) Å, S-C 1.71(2) Å and C=C 1.40(3) Å, together with the square-planar coordination of Pt in PtS₄, suggest considerable conjugation in the metal cycles.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1207–1209, July, 1993.     

Novel crystal engineering in the crown ether nickel maleonitriledithiolate complexes,synthesis and crystal structures of [Na(N15C5)2]2[Ni(mnt)2] and [Na(N15C5)]2[Ni(mnt)2]

Reactions of N15C5 (2,3-naphtho-15-crown-5) with nickel maleonitriledithiolate sodium complex, Na₂[Ni(mnt)₂] (mnt?=?maleonitriledithiolate) using different molar ratios (2?:?1 and 4?:?1) afforded two structurally different complexes [Na(N15C5)₂]₂[Ni(mnt)₂] (1) and [Na(N15C5)]₂[Ni(mnt)₂] (2). The sandwich [Na(N15C5)₂]⁺ and mono-capped [Na(N15C5)]⁺ organic cations are observed in the crystals of 1 and 2, respectively, with the same [Ni(mnt)₂]^2? inorganic conteranions. It is these structurally different organic cations that lead to the dissimilar structures. Complex 1 exhibits a one-dimensional (1D) chain-like structure assembled by intercantionic {[Na(N15C5)₂]⁺}_∞ π–π stacking interactions and electrostatic interactions, while 2 displays a novel two-dimensional (2D) corrugated sheet-like structure constructed by Na–N interactions which occur between the [Na(N15C5)]⁺ inorganic cations and [Ni(mnt)₂]^2? inorganic anions.     

P-C Bond Cleavage in Platinum Complexes Containing bis (Diphenylphosphino) Methane Promoted with a Phase-Transfer Catalyst

With a phase-transfer catalyst, Pt-dppm (dppm = Ph₂PCH₂PPh₂) complexes undergo basic hydrolysis, in which a dppm ligand is hydrolyzed to produce PPh₂Me and PPh₂OH (or PPh₂O). The ease of this hydrolysis reaction depends partly on the molecular charges of the metal complexes. Hydrolysis of neutral [Pt(dppm)(L-L)] (L-L = S₂CO², S₂P(O)(OEt)^2? and mnt = S₂C₂(CN)₂^2?) is slower than that of monocationic [Pt(dppm)(L′-L′)]Cl (L′-V = S₂CNEt₂-, (CH₂)₂S(O)Me and acetylacetonate) compounds. Among the neutral compounds, hydrolysis of [Pt(dppm)(mnt)] is more rapid than that of the other two. These results are rationalized according to the ease with which partial positive charges are induced on the dppm phosphorus atoms. The steric effect due to ligands trans to dppm also influences the rate of hydrolysis of Pt-dppm compounds. When trans ligands are Ph₂P(CH)₂PPh₂, Ph₂P(CH₂)₃PPh₂ and (Ph₂PO₂)H, no hydrolysis of dppm occurs. Hydrolysis of Pt-dppm compounds depends further on the concentrations of both the phase-transfer catalyst and OH^? ions. All these results are consistent with nucleophilic attack of OH^? on dppm phosphorus atoms to release strain in the Pt-dppm ring.     

Radical CpNi(dithiolene) and CpNi(diselenolene) complexes: Synthetic routes and molecular properties

The formally Ni(III) d⁷ radical organometallic complexes formulated as [CpNi(dithiolene)] can be prepared by different routes involving different CpNi sources such as the Ni^(I) [CpNi(CO)]₂, the Ni^(II) [Cp₂Ni] or [CpNi(cod)]⁺ or the Ni^(III) [Cp₂Ni]⁺ complexes. As dithiolene precursors, the naked dithiolate, the mono- as well as bis-(dithiolene) metal complexes were investigated. The highest yields are generally associated with an appropriate redox match, that is a CpNi^(II) precursor with a formally Ni^(IV) [Ni(dithiolene)₂]⁰ complex, or a CpNi^(III) precursor with a formally Ni^(III) [Ni(dithiolene)₂]^? complex. The structural, electrochemical and spectroscopic (UV–vis–NIR, EPR) properties of more than twenty complexes are described and compared, with the help of DFT calculations. They all exhibit a small optical gap with a low-energy absorption band in the Near Infra-Red region, between 700 and 1000 nm. The smaller electrochemical and optical gap found in the [CpNi(dmit)] and [CpNi(dddt)] complexes is correlated with an extensive delocalisation of the spin density in these complexes, while the other members of the series are characterized with a larger and sizeable spin density on the cyclopentadienyl ring.     

Synthesis and Characterization of One-dimensional Dicyclohexyl-18-crown-6 Complexes with M2[Cd(mnt)2] (M = Na, K)

Two supramolecular crown ether complexes [Na(DC18C6-A)(H₂O)]{[Na(DC18C6-A)][Cd(mnt)₂]} (1) and [K(DC18C6-A)]₂[Cd(mnt)₂] (2) (DC18C6-A = cis-syn-cis-dicyclohexyl-18-crown-6, isomer A; mnt = maleonitriledithiolate) have been synthesized and characterized by elemental analysis, FT-IR spectroscopy and X-ray single crystal diffraction. Complex 1 is composed of one [Na(DC18C6-A)(H₂O)]⁺ complex cation and one {[Na(DC18C6-A)][Cd(mnt)₂]}⁻ complex anion and displays an infinite chain-like structure through N–Na–N interactions. In complex 2, [K(DC18C6-A)]⁺ complex cation and [Cd(mnt)₂]²⁻ complex anion afford a novel 1D ladder-like structure by N–K–N, N–K–S interactions.     

Conducting LB films based on metal complexes of sulphur donor ligands

Preliminary studies are reported on the film forming characteristics of compounds such as dialkyldimethylammonium-M (dmit)₂ and dialkyldimethylammonium-M (mnt)₂ where M = Ni, Pt or Pd. All materials investigated show good monolayer behaviour and deposit readily onto evaporated aluminium or gold films. This is confirmed by surface potential and FTIR measurements. The lateral conductivity of deposited films increases by many orders of magnitude when exposed to bromine vapour.     

Preparation and properties of [PtII(SS)(NN)]-type complexes and their iodine-doped analogues

Summary Complexes of the general formula [Pt(SS) (NN)], where SS is dddt (5,6-dihydro-1,4-dithiin-2,3-dithiolate) or pddt (6,7-dihydro-5H-1,4-dithiepin-2,3-dithiolate) and NN is bipy (2,2-bipyridine) or phen (1,10-phenanthroline), were prepared by the reaction of [PtCl₂(NN)] with dithiolate ligands. The¹H-n.m.r. spectra shows upfield shifts in the bipy or phen signals upon substitution of the chlorides in [PtCl₂(bipy)] or [PtCl₂(phen)] by dddt or pddt. The u.v.-vis. spectra exhibits intense intramolecular ligand-to-ligand charge transfer bands ca. 600 nm. Cyclic voltammograms show a reversible oxidation step, assigned to [Pt(SS) (NN)]⁰/[Pt(SS)(NN)]⁺. When the complexes were partially oxidized by I₂, two broad e.s.r. signals atg = 1.91,g = 2.02 appeared. Raman spectra show the presence of I ₃ ^– and I^5/– in the iodine-doped complexes. The electrical conductivities of the neutral mixed ligand complexes (10^–9-10^–10S cm^–1) are raised to 10^–7–10^–8S cm^–1 by I₂ doping.     

Bildung und Struktur des [{η2‐tBu2P–P}Pt(PHtBu2)(PPh3)]

Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XX Formation and Structure of [{η²‐^tBu₂P–P}Pt(PH^tBu₂)(PPh₃)] [{η²‐^tBu₂P¹–P²}Pt(P³Ph₃)(P⁴Ph₃)] ( 2 ) reacts with ^tBu₂PH exchanging only the P³Ph₃ group to give [{η²‐^tBu₂P¹–P²}Pt(P³H^tBu₂)(P⁴Ph₃)] ( 1 ). The crystal stucture determination of 1 together with its ³¹P{¹H} NMR data allow for an unequivocal assignment of the coupling constants in related Pt complexes. 1 crystallizes in the triclinic space group P1 (no. 2) with a = 1030.33(15), b = 1244.46(19), c = 1604.1(3) pm, α = 86.565(17)°, β = 80.344(18)°, γ = 74.729(17)°.     

Phenylimido Complexes of Technetium and Rhenium with Maleonitriledithiolate

[Tc(NPh)Cl₃(PPh₃)₂] or [Re(NPh)Cl₃(PPh₃)₂] react with two equivalents of Na₂mnt (mnt^2– = 1,2‐dicyanoethene‐1,2‐dithiolate) with formation of anionic complexes of the composition [M(NPh)(mnt)₂]^–. The products can be isolated as large red blocks of their AsPh₄⁺ salts. The complex anions contain square‐pyramidal coordinated metal atoms with the phenylimido ligands in apical positions. The M–N–C bonds are almost linear. A similar phenylimido complex with an additional amino group was synthesized from [Re(NC₆H₄‐4‐NH₂)Cl₃(PPh₃)₂]. The presence of such substituents may allow coupling of the metal complexes to biomolecules such as peptides, proteins, or sugars, provided the M=N bonds are sufficiently stable against hydrolysis.     

Clusteraufbau durch Photolyse von Azidokomplexen des Platins und Golds. Synthesen und Kristallstrukturen von [(Ph3PAu)6(AuCl)3Pt(CO)], [(dppe)PtCo2(CO)7] und [(Ph3PAu)4Pt(dppe)](PF6)2

Cluster Synthesis by Photolysis of Azido Complexes of Platinum and Gold. Syntheses and Crystal Structures of [(Ph₃PAu)₆(AuCl)₃Pt(CO)], [(dppe)PtCo₂(CO)₇] and [(Ph₃PAu)₄Pt(dppe)](PF₆)₂ Photolysis of a mixture of Ph₃PAuN₃, Ph₃PAuCl and (Ph₃P)₂Pt(N₃)₂ in THF yields after chromatographic separation with CH₂Cl₂/EtOH as eluens the cluster [(Ph₃PAu)₆(AuCl)₃Pt(CO)] ( 1 ). It crystallizes in the triclinic space group P1 with the lattice parameters a = 2 139.3(4), b = 2 457.1(4), c = 2 561.9(1) pm, α = 79.74(9)°, β = 80.06(6)°, γ = 66.05(5)°, Z = 4. The nine gold atoms form a fragment of an icosahedron with the platinum atom in its center. Upon photolysis of (dppe)Pt(N₃)₂ with Co₂(CO)₈ in THF one m?₂-CO ligand of the cobalt carbonyl is substituted by a (dppe)Pt group. The resulting cluster [(dppe)PtCo₂(CO)₇] ( 2 ) crystallizes monoclinically in the space group P2₁/n with a = 1 303.9(3), b = 1 768.1(8), c = 1 461.4(4) pm, β = 102.81(1)°, Z = 4. Photolysis of 2 with excess Ph₃PAuN₃ affords the clusters [(Ph₃PAu)₄Pt(dppe)]²⁺ ( 3 ), and [(Ph₃PAu)₆AuCo₂(CO)₆]⁺. 3 crystallizes with PF as counterions in the triclinic space group P1 with a = 1 369.1(4), b = 1 505.0(4), c = 2 773.0(8) pm, α = 84.74(1)°, β = 87.37(2)°, γ = 65.94(2)°, Z = 2. The Au₄Pt skeleton of 3 forms a trigonal bipyramid with the platinum atom in equatorial position.     

Synthesis,crystal structure and magnetic properties of [1-(4′-bromobenzyl)-4-methylquinolinium] [Ni(mnt)2] complex (mnt2 − =maleonitriledithiolate)

A new ion-pair complex, [BrBzMeQl][Ni(mnt)₂] (1) ([BrBzMeQl]⁺?=?1-(4′-bromobenzyl)-2-methylquinolinium; mnt^2??=?maleonitriledithiolate), has been prepared and characterized. X-ray diffraction analysis shows that the Ni(mnt)₂ anion and [BrBzMeQl]⁺ cations of 1 form completely segregated stacking columns, with the Ni?···?Ni distances alternating between 3.717 and 4.466?Å?in the Ni(mnt)₂ stacking column. The variable-temperature magnetic susceptibilities of 1 have been measured over the range 75–300?K and the results reveal that the complex exhibits antiferromagnetic behavior.