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A straightforward synthesis methodology for the preparation of rhodium(II) carboxylates [Rh2{O2CCH2(OCH2CH2)2OCH3}4]n (1) and [Rh{μ-O2CCH2(OCH2CH2)2OCH3}2(PPh3)]2 (2) is reported. The ethanol-mediated reduction of RhCl3·3H2O with [K{O2CCH2(OCH2CH2)2OCH3}] produced 1, which on further addition of PPh3 afforded 2. Single-crystal X-ray diffraction studies of 2 were carried out showing a paddlewheel arrangement of the dirhodium(II) tetracarboxylate unit with a Rh–Rh distance of 2.4599(5) A. Compounds 1 and 2 were applied in the formation of rhodium nanoparticles (NPs) using 1,2-ethanediol as reducing reagent and poly(vinylpyrrolidone) (PVP) as capping component. Rhodium NPs with a narrow size distribution (

The series of biferrocenyl-functionalized phosphines Bfc(PR2)/Bfc(Se═PR2) (R = C6H5 (6/14), C6H4-2-CH3 (7/15), cC4H3O (8/16), cC6H11 (9/17); Bfc = 1′-biferrocenyl, Fe(η5-C5H5)(η5-C5H4)Fe(η5-C5H4)2) and biferrocenyl diphosphines bfc(PR2)2/bfc(Se═PR2)2 (R = C6H5 (10/18), C6H4-2-CH3 (11/19), cC4H3O (12/20), cC6H11 (13/21); bfc = 1′,1‴-biferrocenyl, (Fe(η5-C5H4)2)2) have been prepared by consecutive synthesis methodologies. The reaction of 6–9 with [Pd(Et2S)2Cl2] (22) gave the appropriate palladium dichloride complexes trans-[Pd(Bfc(PR2))2Cl2] (R = C6H5 (23), C6H4-2-CH3 (24), cC4H3O (25), cC6H11 (26)). The structures of 15, 16, 21, 23, and 25 in the solid state were determined by single-crystal X-ray diffraction studies, showing that the structural parameters of these molecules correspond to those of related seleno phosphines and phosphino palladium dichloride complexes. Additionally, all complexes were characterized by cyclic voltammetry using [nBu4N][PF6] and [nBu4N][B(C6F5)4]as supporting electrolytes. Pho...

Two cadmium(II) iodide complexes, [Cd(Detu)2I2] (1) and [Cd(Diaz)2I2] (2) (Detu = N,N′-diethylthiourea; Diaz = 1,3-diazinane-2-thione) have been prepared and their structures been determined by X-ray crystallography. The crystal structures show that both complexes are mononuclear with the cadmium atom coordinated to two iodide ions and two thione ligands adopting a distorted tetrahedral geometry. Whereas, 2 exists as discrete monomeric species, the structure of 1 consists of three crystallographically independent molecules. The complexes were also characterized by IR and NMR (1H and 13C) spectroscopy. The crystal structures of [Cd(Detu)2I2] (1) and [Cd(Diaz)2I2] (2) show that the complexes are mononuclear with the cadmium atom coordinated to two iodide ions and two thione ligands adopting a distorted tetrahedral geometry. Whereas, 2 exists as discrete monomeric species, the structure of 1 consists of three crystallographically independent molecules.

The solid state complexes, solvatochromic and acidochromic behaviour of four merocyanine-type dyes derived from barbituric and thiobarbituric acid and their use as solvatochromic probe molecules for coloured surfaces are described. The dyes were obtained by condensation reaction of barbituric, N-methylbarbituric, N,N′-dimethylbarbituric and thiobarbituric acid with 4-N,N-dimethylaminocinnamaldehyde. The dyes were characterised by means of liquid and solid state NMR techniques (1H MAS NMR, 1H–1H DQ MAS NMR, 13C CPMAS NMR), single-crystal X-ray analysis, UV/vis and IR measurements. The solvatochromism has been investigated in 43 solvents and interpreted in terms of Kamlet–Taft parameters α, β, and π*. Altogether, the solvatochromic properties of these four dyes were determined mainly by the hydrogen bond donating (HBD) ability and the polarisability/dipolarity of a solvent. The interactions of the dyes with oxidic and metal surfaces were studied. Their perichromic behaviour was compared with that of established solvatochromic dyes for the determination of α, β, and π*, namely dicyano-bis-(1,10-phenanthroline)-iron(II)-complex (1), 3-(4-amino-3-methylphenyl)-7-phenyl-benzo-[1,2-b:4,5-b′]-difuran-2,6-dione (2) and 4-tert-butyl-2-(dicyanomethylene)-5-[4-(diethylamino)benzylidene]-Δ3-thiazoline (3). The barbituric acid dyes were used to probe the surface polarity of coloured oxides like tungsten(VI) oxide and iron(III) oxide. The interactions between the dyes and metals like zinc and aluminium were also investigated.

The reaction of [Bi(22)O(26)(OSiMe(2)tBu)(14)] (1) in THF with salicylic acid gave [Bi(22)O(24)(HSal)(14)] (2) first, which was converted into [Bi(38)O(45)(HSal)(22)(OH)(2)(DMSO)(16.5)]·DMSO·H(2)O (3·DMSO·H(2)O) after dissolution and crystallization from DMSO. Single-crystal X-ray diffraction analysis and ESI mass spectrometry associated with infrared multi-photon dissociation (IRMPD) tandem MS experiments confirm the formation of the large and quite stable bismuth oxido cluster 3. The reaction of compound 2 with the butoxycarbonyl(BOC)-protected amino acids phenylalanine and valine (BOC-PheOH and BOC-ValOH), respectively, resulted in the formation of chiral [Bi(38)O(45)(BOC-AA)(22)(OH)(2)] (AA=deprotonated amino acid), as shown by a combination of different analytical techniques such as elemental analysis, dynamic light scattering, circular dichroism spectroscopy, and ESI mass spectrometry.

The synthesis and characterization of a series of metallocenylphosphanes of the type PR2Mc/Se=PR2Mc [Mc = Fc = Fe(η5-C5H4)(η5-C5H5), R = C6H5 (3a/4a), 2-MeC6H4 (3b/4b), c-C4H3O (3c/4c), tBu (3d/4d), c-C6H11 (3e/4e); Mc = Rc = Ru(η5-C5H4)(η5-C5H5), R = C6H5 (6a/7a), 2-MeC6H4 (6b/7b), c-C4H3O (6c/7c), c-C6H11 (6d/7d)] and their palladium complexes [PdCl2(PR2Mc)2] [Mc = Fc, R = C6H5 (9a), 2-MeC6H4 (9b), c-C4H3O (9c), tBu (9d), c-C6H11 (9e); Mc = Rc, R = C6H5 (10a), 2-MeC6H4 (10b), c-C4H3O (10c), c-C6H11 (10d)] is reported. The solid-state structure of 4b confirms the tetrahedrally distorted geometry at phosphorus with the o-tolyl groups indicating steric congestion, which is confirmed by 1H and 13C{1H} NMR spectroscopy. Phosphanes 3, 4, and 9 were characterized by cyclic voltammetry with [N(nBu)4][B(C6F5)4] as the supporting electrolyte. In general, the first oxidation occurs at the phosphane metallocenyl unit(s), although the appropriate Pd complexes are oxidized at more positive potentials. Depending on the phosphane or selenophosphane, follow-up reactions occur, which are discussed. In contrast, the palladium complexes show reversible redox behavior. UV/Vis/NIR spectroelectrochemical studies carried out on 9b indicate an electrostatic interaction between the two terminal ferrocenyl groups. All of the palladium complexes were examined as catalysts in Heck and Suzuki C–C cross-coupling and showed high catalytic activities. These results can be correlated to the electronic (1J) parameters of the selenophosphanes.

Protein kinase C (PKC) is a widely studied molecular target for the treatment of cancer and other diseases. We have approached the issue of modifying PKC function by targeting the C1 domain in the regulatory region of the enzyme. By using the X-ray crystal structure of the PKCδ C1b domain combined with molecular modeling, we discovered (3-aminodecahydro-1,4-methanonaphthalen-2-yl)methanol as a novel C1 domain ligand. The stereoselective synthesis of this tricyclic γ-amino alcohol was based on two successive Diels–Alder reactions to construct the six continuous stereocenters of the key intermediate.

A mixed-ligand silver(I) complex of triphenylphosphine and N,N′-dibutylthiourea (Dbtu), [Ag(Ph3P)2(Dbtu)2]NO3, is prepared and its structure in the solid state is determined by X-ray crystallography. X-ray structure of this complex shows that it is mononuclear with the silver atom coordinated by two PPh3 and two dibutylthiourea ligands adopting a distorted tetrahedral geometry. The crystal structure shows the formation of 1-D chains through intermolecular hydrogen bonding interactions between N-H of Dbtu and nitrate ions. The new complex is also characterized by IR and NMR (1H and 31P) spectroscopy. The spectroscopic data are discussed in terms of the nature of bonding. A similar mixedligand complex is also prepared for tetramethylthiourea (Tmtu), but the structure of the resulting compound shows that it is a bis(phosphine) complex, [Ag(PPh3)2NO3] rather than a mixed-ligand complex.

1,4-Diazidobuta-1,3-dienes (Z,Z)-10, 17, and 21 were photolyzed and thermolyzed to yield the pyrid-azines 13, 20, and 23, respectively. To explain these aromatic final products, the generation of highly strained bi-2H-azirin-2-yls 12, 19, and 22 and their valence isomerization were postulated. In the case of meso- and rac-22, nearly quantitative formation from diazide 21, isolation as stable solids, and complete characterization were possible. On the thermolysis of 22, aromatization to 23 was only a side reaction, whereas equilibration of meso- and rac-22 and fragmentation, which led to alkyne 24 and acetonitrile, dominated. Prolonged irradiation of 22 gave mainly the pyrimidine 25. The change of the configuration at C-2 of the 2H-azirine unit was observed not only in the case of bi-2H-azirin-2-yls 22 but also for simple spiro-cyclic 2H-azirines 29 at a relatively low temperature (75 degrees C). The fragmentation of rac-22 to give alkyne 24 and two molecules of acetonitrile was also studied by high-level quantum chemical calculations. For a related model system 30 (methyl instead of phenyl groups), two transition states TS-30-31 of comparable energy with multiconfigurational electronic states could be localized on the energy hypersurface for this one-step conversion. The symmetrical transition state complies with the definition of a coarctate mechanism.

Individual synthetic routes to heterobimetallic Ti(IV)–Ag(I) acetylides of type {[Ti](μ-σ,π-C CR1)2}AgC CR2 ([Ti] = (η5-C5H4SiMe3)2Ti: R1 = SiMe3: 6, R2 = SiMe3; 7, R2 = Ph. R1 = tBu: 8, R2 = SiMe3; 9, R2 = Ph. [Ti] = (η5-C5H5)2Ti): 10, R1 = tBu, R2 = SiMe3) including (i) the reaction of {[Ti](μ-σ, π-C CR1)2}AgNO3 ([Ti] = (η5-C5H4SiMe3)2Ti): 1, R1 = SiMe3; 2, R1 = tBu. [Ti] = (η5-C5H5)2Ti: 3, R1 = tBu) with LiC CR2 (4, R2 = SiMe3; 5, R2 = Ph) and (ii) treatment of [Ti](C CSiMe3)2 ([Ti] = (η5-C5H4SiMe3)2Ti) (11) with [AgC CR2] (12, R2 = SiMe3; 13, R2 = Ph) are described. The reactions of 1–3 with 4 or 5 appeared to be sensitive towards stoichiometry because an excess of 4 or 5 resulted in the formation of [(Ag(C CR2)2)Li(OEt2)]n (14) and [Ti](C CR1)2. Coordination polymer 14 is also accessible, when, for example, [AgC CSiMe3] (12) is treated with 1 eq. of LiC CSiMe3 (4) in diethyl ether. The titanium(IV)–silver(I) acetylides 6–10 are stable in the dark and at low temperature, while on exposure to light and on heating they decompose to give R2C C–C CR2 together with [Ti](C CR1)2 and elemental silver. Complexes 6–10 contain a mono-nuclear AgC CR2 entity stabilized by the chelate-bonded organometallic π-tweezer molecule [Ti](C CSiMe3)2, which was evinced by structure determination of 7 in the solid state. In 14 linear [Me3SiC C–Ag–C CSiMe3]− units are connected by [Li(OEt2)]+ building blocks forming a coordination polymer.

The synthesis and properties of heterobimetallic Ti–Cd complexes of type {[Ti](μ-η1:η2–C CR)2}CdX2 ([Ti] = Ti(η5–C5H4SiMe3)2; R = SiMe3: 3a, X = Cl; 3b, X = Br; 3c, X = I; R = Fc: 3d, X = Br; Fc = Fe(η5–C5H4)(η5–C5H5) is reported. These compounds were accessible by treatment of [Ti](C CR)2 (1a, R = SiMe3; 1b, R = Fc) with the cadmium salts CdX2 (2a, X = Cl; 2b, X = Br; 2c, X = I) in a 1:1 M ratio in diethyl ether. Dissolving, for example, 3b in tetrahydrofuran afforded coordination polymer [Cd(μ-Br)2(thf)2]n (4) along with the tweezer molecule 1a. Treatment of 3b with two equiv of LiC CFc (5) gave {[Ti](μ-η1:η2–C CSiMe3)2}Cd(C CFc)2 (6) which eliminated at ambient temperature the all-carbon buta-1,3-diyne FcC C–C CFc (7) producing 1a and elemental Cd. The same reaction behavior was observed, when 2b was reacted with 5. The thus obtained bis(alkynyl) cadmium complex Cd(C CFc)2 (8) is redox-active at low temperature producing 7 and Cd(0). When mercury halides HgX2 (9a, X = Cl; 9b, X = Br) are used, then the titanocene dihalides [Ti]X2 (10a, X = Cl; 10b, X = Br) together with Me3SiC C–C CSiMe3 (11) and Hg(0) were formed. Nevertheless, mercury acetylides were available by treatment of Hg(OAc)2 (12) with HC CFc (13) in a 1:2 M ratio. Thus obtained Hg(C CFc)2 (14) gave with [CuBr] (15) coordination polymer [{Hg(η2-C CFc)2}(Cu2(μ-Br)2]n (16), while with [AgPF6] oxidation of the ferrocenyl moieties took place affording dicationic [Hg(C CFc)2]2+ (18). The structures of 3b and 4 in the solid state are reported. Compound 3b shows the typical characteristics for heterobimetallic organometallic π-tweezer complexes with cadmium in a tetrahedral environment, while 4 corresponds to a one-dimensional coordination polymer in which the Cd(II) ions are linked in a edge-sharing fashion by bromide bridges in the pseudo-equatorial plane. The appropriate tetrahydrofuran molecules are completing the pseudo-octahedral coordination sphere at cadmium. The cyclic voltammogram of 14 is reported showing a single reversible redox event at E0 = 0.108 V with ΔEp = 76 mV indicating that there is no communication between the Fc termini along the mercury acetylide unit.

Uranyl β-diketone complex UO2(tfa)2·H2O (3) (tfa = deprotonated 4,4,4,-trifluoro-1-(2-furyl)-1,3-butanedione) has been successfully prepared by reacting UO2(OAc)2·2H2O (OAc = O2CMe) with two equivalents of 4,4,4,-trifluoro-1-(2-furyl)-1,3-butanedione (H-tfa: 1) in ethanol. Complex 3 was characterized by elemental analysis and FT-IR. Dissolving 3 in ethanol gave during several days single crystals of [UO2(tfa)2(OHCH2CH3)] (4), wherein one ethanol molecule replaces aqua ligand. The solid-state structure of 4 was determined by a single X-ray analysis. Crystal data of C18H14F6O9U: a = 13.7163(7), b = 20.7528(10), c = 7.4664(4) A, β = 90.818(4)°, space group P2(1)/c, Z = 4 and dcalc = 2.270 mg/m3. Complex 4 adopted a distorted pentagonal bipyramidal geometry. The coordinated oxygen atoms of tfa (deprotonated-1) ligands are occupying equatorial positions, while the oxygen atoms of UO 2 2 + are still in the axial positions. The formation of the π–π interactions together with hydrogen bonded result in the set up a 3D-supramolecular architecture. The electronic absorption of 3 is reported and discussed.

Copper(I) complexes of thioureas having the general formulae [CuLnBr] and [CuLn]Br [where, n = 1 − 4 and L = thiourea (Tu), N-methylthiourea (Metu), N-ethylthiourea (Ettu), N,N′-dipropylthiourea (Dprtu), N,N′-dibutylthiourea (Dbtu) or N,N′-diphenylthiourea (Dphtu)] were prepared and characterized by elemental analysis, IR, and NMR (1H and 13C) spectroscopy. The crystal structure of one of them, [Cu(Metu)4]Br (1), was determined by X-ray crystallography. The X-ray structure of 1 describes a tetrahedral geometry around copper(I) with all Metu ligands binding through sulfur atoms. An upfield shift in the 13C NMR and downfield shift in the 1H NMR spectra are consistent with the thione coordination to copper(I). Antimicrobial activities of the complexes were evaluated by the minimum inhibitory concentration method. The results showed that only [Cu(Ettu)3Br] was effective in inhibiting the growth of all the tested organisms (gram-positive, gram-negative bacteria, and Candida sp.), while the other complexes were not effective against all the organisms.

Three different methods to prepare 1,4-diazidobuta-1,3-dienes are presented: nucleophilic substitution of electron-poor dichlorinated substrates, nucleophilic addition of hydrazoic acid at an electron-deficient diallene, and a sequence of prototropic isomerizations of propargyl sulfones followed by nucleophilic additions. In all cases, isolation and assignment of the diastereomeric products was possible, and some sequential reactions, such as reduction or 1,3-dipolar cycloaddition of the azido groups, were performed.

Consecutive synthesis methodologies for the preparation of carbosilanes (Ph)(Me)Si((CH2)3B(OH)2)2 (2), Si(C6H4-4-SiMe2((CH2)3B(OH)2))4 (5), (Ph)(Me)Si((CH2)3OH)2 (3), and Si(C6H4-4-SiMe3−n((CH2)3OH)n)4 (6a, n = 1; 6b, n = 2; 6c, n = 3) are reported. Boronic acids 2 and 5 are accessible by treatment of (Ph)(Me)Si(CH2CH CH2)2 (1) or Si(C6H4-4-SiMe2(CH2CH CH2))4 (4a) with HBBr2·SMe2 followed by addition of water, while 3 and 6 are available by the hydroboration of 1 or Si(C6H4-4-SiMe3−n(CH2CH CH2)n)4 (4a, n = 1; 4b, n = 2; 4c, n = 3) with H3B·SMe2 and subsequent oxidation with H2O2. The single molecular structure of 6a in the solid state is reported. Representative is that 6a crystallized in the chiral non-centrosymmetric space group P212121 forming 2D layers due to intermolecular hydrogen bond formation of the HO functionalities along the crystallographic a and c axes.

The synthesis of dimeric [Mn2Cl2(μ-Cl)2(dipa)2]·MeOH (3) (dipa = dipyridylmethylamine) from [MnCl2(H2O)4] (1) and dipa (2) and its structural characterization is reported. In the solid state complex 3 is dimeric and possesses crystallographically imposed C2 symmetry, which differs from similar dimanganese(II) complexes showing an inversion symmetry for the central Mn(μ-Cl)2Mn arrangement. Each manganese atom is thereby bound by three nitrogen atoms from a facially coordinated dipa ligand, and three chlorides (1 terminal and 2 μ-bridging) in an octahedrally distorted fashion. The cylovoltammogram of 3 displays that the two manganese(II) ions can independently be oxidized. The magnetic properties of 3 were determined by susceptibility measurements versus temperature. The intramolecular J parameter was determined to a value of J = (−5.2 ± 0.5) cm−1.

Substituted 1-azidocyclopentenes and 1-azidocyclohexenes were photolyzed to generate 2,3-bridged 2H-azirines. In the case of bridgehead azirines with a six-membered carbocycle, detection by NMR spectroscopic analysis was possible, whereas even kinetically stabilized bridgehead azirines with a five-membered ring could not be characterized by low-temperature NMR spectroscopic analysis. Thus, a recent report on the latter heterocycles was corrected. Depending on the substitution pattern, irradiation of 1-azidocyclopentenes either led to products that can be explained on the basis of short-lived 2,3-bridged 2H-azirines, or gave secondary products generated from triplet nitrenes. The diverse photoreactivity of 2,3-bridged 2H-azirines was also studied by quantum chemical methods (DFT, CCSD(T), CASSCF(6,6)) with respect to the singlet and triplet energy surfaces. The ring-opening processes leading to the corresponding vinyl nitrenes were identified as key steps for the observed reactivity.

The reaction of [Fe(η 5 -C 2 H 4 PPh 2 )(η 5 -C 5 H 4 terpy)] (5; terpy = 2,2':6',2"-terpyridin-4'-yl) with diverse transition-metal compounds including [PtCl 2 (Et 2 S) 2 ], [Pd(cod)X 2 ], [AuCl(tht)], [CuBr], [Mo(CO) 4 (nbd)], and [{RhCl(cod)} 2 ] (X = Cl, Br; tht = tetrahydrothiophene; nbd = norbornadiene; cod = cyclooctadiene) to afford heterobi- and trimetallic complexes and a coordination polymer is reported. The following compounds were prepared: [Fe(η 5 -C 2 H 4 PPh 2 (PtCl 2 (SEt 2 )})(η 5 -C 5 H 4 terpy)] (7), trans-[PtCl 2 {(Ph 2 P-η 5 -C 2 H 4 )(η 5 -C 5 H 4 terpy)-Fe} 2 ] (9), [Fe(η 5 -C 2 H 4 PPh 2 PdCl 2 )(η 5 -C 5 H 4 terpy)] (12), [Fe{η 5 -C 5 H 4 PPh 2 (Cl 3 Pd - )}(η 5 -C 5 H 4 terpy{(dmso) 2 ClNi + })] (14), trans-[PdX 2 {(Ph 2 P-η 5 -C 5 H 4 )(η 5 -C 5 H 4 terpy)Fe} 2 ] (16a, X = Cl; 16b, X = Br), [Mo(CO) 4 {(η 5 -C 5 H 4 PPh 2 )(η 5 -C 5 H 4 terpy)Fe} 2 ] (17), [Fe{η 5 -C 5 H 4 Ph 2 P(CuBr)}(η 5 -C 5 H 4 terpy)] n (19), [Fe(η 5 -C 5 H 4 Ph 2 P(AuCl)}(η 5 -C 5 H 4 terpy)] (22), [Fe(η 5 -C 5 H 4 Ph 2 P-(Rh(cod)Cl})(η 5 -C 5 H 4 terpy)] (23), [Ru({η 5 -C 5 H 4 Ph 2 P(AuCl)}-(η 5 -C 5 H 4 terpy)Fe) 2 ]Cl 2 (25), and [Fe{η 5 -C 5 H 4 PPh 2 -(PdCl 2 )}{η 5 -C 5 H 4 -CH=CHC(O)(py)}] (26). The molecular structures of 5, 9, 12, 14, 16b, 22, and 26 in the solid state are reported. They show typical features of related phosphanyl-ferrocenes and terpyridylferrocenes. Characteristic of 12 is a C-H activation as a result of the close distance of palladium to the terpyridyl moiety. Complexes 12, 26, and [PdCl 2 (dppf)] [dppf = 1,1'-bis(diphenylphosphanyl)ferrocene], for comparison, were used in preliminary studies as catalysts in the carbon-carbon coupling of iodobenzene with tert-butyl acrylate to give (E)-tert-butyl cinnamate. The conversion amounts to 80 % with a turnover number of 160 and turnover frequency of 48 h -1 .

Supercrowded 2,3,4,5-tetraferrocenylthiophene (4) has been synthesized by a fourfold Negishi ferrocenylation of tetrabromothiophene (3) with FcZnCl (2) (Fc = (η5-C5H4)(η5-C5H5)Fe) in the presence of [(Ph3P)4Pd] as catalyst. The electronic and structural properties of 4 were investigated with UV−vis spectroscopy and single-crystal X-ray diffractometry. Complex 4 adopts a solid-state structure, with not one of the ferrocenyl substituents being coplanar with the thiophene ring. Cyclic, square wave, and linear sweep voltammetry and in situ near-IR spectroelectrochemistry highlight the electron-transfer properties of 4. Compound 4 displays four electrochemically reversible one-electron-transfer processes with formal reduction potentials of E°′ = −161 mV for the 4/4+ couple, 58 mV for the 4+/42+ couple, 418 mV for the 42+/43+ couple, and 604 mV vs Fc/Fc+ for the 43+/44+ couple. ΔE°′ values of 219, 360, and 186 mV indicate significant electrostatic interaction among the four terminal ferrocenyl groups as oxidati...

The palladium(II) complex, [Pd(PPh3)2(Imt)2]Cl2 · 3.5H2O (I) (Imt = imidazolidine-2-thione), has been synthesized and characterized by IR, NMR, and X-ray crystallography. An upfield shift in the >C=S resonance of Imt in the 13C NMR spectrum and a downfield shift in the N-H resonance in 1H NMR are consistent with the sulfur coordination of Imt to palladium(II). In the crystal structure of I, the central palladium atom is coordinated to two thione sulfur atoms of Imt and to two phosphorus atoms possessing a square-planar environment with the average cis and trans bond angles of 89.60° and 167.31°, respectively. The title complex was screened for antimicrobial effects, and the results showed that it exhibits moderate activities against gram-negative bacteria (E. coli, P. aeruginosa). The complexes also exhibited significant activities against yeast (C. albicans, S. serevisaiae).

Dicopper dicarboxylates [(R3P)mCuXCu(PR3)m] (5a, X = O2CCO2, R = Ph, m = 2; 5b, X = O2CCO2, R = nBu, m = 3) were prepared by treatment of [Cu2O] (1a) with HO2CCO2H (2a) in presence of PR3 (4a, R = Ph; 4b, R = nBu). A further synthesis approach to mono- and dicopper dicarboxylates is given using an electrolysis cell equipped with Cu electrodes and charged with acids H2X and phosphanes R3P. Without addition of a base mononuclear [(nBu3P)mCuXH] (6a, m = 3, XH = O2CCO2H, 6b, m = 3, XH = O2CCH2CO2H, 6c, m = 3, XH = O2CCH2CH2CO2H, 6d, m = 2, XH = O2C-2-C5H4N-6-CO2H) was formed, whereas in presence of NEt3 (3), the dicopper systems [(R3P)mCuXCu(PR3)m] (5a, X = O2CCO2, R = Ph, m = 2; 5b, X = O2CCO2, R = nBu, m = 3; 5c, X = O2CCH2CO2, R = nBu, m = 3; 5d, X = O2CCH2CH2CO2, R = nBu, m = 3; 5e, X = O2C-2-C5H4N-6-CO2, R = nBu, m = 3) were produced. When 6a reacted with [(tmeda)Zn(nBu)2] (7), trimetallic [(tmeda)Zn((nBu3P)3CuO2CCO2)2] (8) was accessible. In this heterobimetallic complex the Zn(tmeda) unit spans two CuO2CCO2 entities. The molecular structures of 5a, 6a and 6d in the solid state were determined by single X-ray structure analysis. Complexes 5a and 6a are monomers, whereas 6d creates in the solid state a linear open chain coordination polymer by hydrogen bridge formation. Characteristic for 6d is the somewhat distorted trigonal bipyrimidal arrangement around the copper atom with the nBu3P ligands in axial and the C5H3NCO2H oxygen and nitrogen atoms in equatorial positions. In 5a the oxalate connectivity binds in a μ-1,2,3,4 fashion being part of a planar Cu2(oxalate) core. TG studies of several mono- and dicopper dicarboxylates were carried out. Release of the PR3 ligands is recognized and the remaining Cu-(di)carboxylate unit decomposes to afford elemental copper and CO2. The deposition of copper onto pieces of PVD-Cu oxidized silicon wafers by applying the spin-coating process and using 5c and 5d as precursors is discussed.

The synthesis of diverse ferrocenyl phosphane nickel carbonyls of type (FcPPh2)Ni(CO)3 (3), (FcPPh2)2Ni(CO)2 (4), fc(PR2Ni(CO)3)2 (R = Ph (6a), R = p-tolyl (6b)), and (fc(PPh2)2)Ni(CO)2 (7) (Fc = (η5-C5H5)(η5-C5H4)Fe, fc = (η5-C5H4)2Fe) starting from FcPPh2 (1), fc(PR2)2 (R = Ph (5a); R = p-tolyl (5b)), and Ni(CO)4 (2) is described. The structures of 3, 4, 6b, and 7 in the solid state are reported, intermolecular interactions by π–π-contacts are discussed. The behavior of 3, 4, 6a, 6b, and 7 towards the oligomerization of ethylene is reported. All compounds, except 4, were found to be inactive in homogeneous ethylene oligomerization, while they exhibit moderate activities (up to 660 kg prod/mol Ni h) in heterogeneous ethylene oligomerization experiments.

Novel donor−acceptor-substituted stilbenes were synthesized by means of nucleophilic aromatic substitution starting from 1-fluoro-2-nitro-4-[(E)-2-(4-nitrophenyl)vinyl]benzene and n-propylamine, L-...

Reactions of N,N′-diethylthiourea (Detu) with copper(I) cyanide and copper(I) iodide in a 2:1 M ratio in acetonitrile resulted in the formation of [Cu(Detu)Cl]3·(CH3CN)0.5 (1) and [Cu(Detu)3I] (2), respectively. In compound 1 each copper atom is coordinated with one sulfur atom of Detu and with one chloride ion forming a centrosymmetric trinuclear core (Cu3S3Cl3) that exhibits a Cu–Cu separation of 2.7383(5) Ǻ indicating the existence of cuprophilic interactions. Complex 2 crystallizes with two independent molecules per asymmetric unit. Each copper atom is coordinated with three sulfur atoms of Detu and with one iodide ion in a tetrahedral arrangement. Reactions of N,N′-diethylthiourea (Detu) with copper(I) cyanide and copper(I) iodide in a 2:1 M ratio in acetonitrile resulted in the formation of [Cu(Detu)Cl]3·(CH3CN)0.5 (1) and [Cu(Detu)3I] (2), respectively. In compound 1 each copper atom is coordinated with one sulfur atom of Detu and with one chloride ion forming a centrosymmetric trinuclear core (Cu3S3Cl3) that exhibits a Cu–Cu separation of 2.7383(5) Ǻ indicating the existence of cuprophilic interactions. Complex 2 crystallizes with two independent molecules per asymmetric unit. Each copper atom is coordinated with three sulfur atoms of Detu and with one iodide ion in a tetrahedral arrangement.

Nanometer thin films of nonsublimable multinuclear transition metal complexes were deposited on Si by means of spin coating to enable photoelectron spectroscopy studies. In combination with density functional theory calculations, photoelectron spectroscopy is applied to gain insight into the electronic and magnetic properties of the complexes.

A novel dinuclear copper(I) complex, [Cu2(μ2-SH)2(PPh3)3] (1) (PPh3 = triphenylphosphine) has been prepared by the reaction of CuCl with triphenylphosphine and mercaptopropanoic acid (MPA) mixed in the ratio of 1:1:1. In the molecular structure of 1, two copper atoms are bridged by S atoms of two monohydrogensulfido anions forming a four-membered ring. The planar Cu2S2 core is characterized by significant cuprophilic interactions (Cu–Cu distance = 2.897 Ǻ). One copper atom in 1 is coordinated with two sulfur atoms and one phosphorus atom of PPh3 adopting a trigonal planar geometry, while the coordination environment around the other copper center is distorted tetrahedral that is completed by two sulfur atoms of SH groups and two phosphorus atoms of PPh3 molecules.

A series of organometallic mono- and disubstituted bis(alkynyl)biferrocenes of type (LnMC≡C)(HC≡C)bfc (LnM = (η5-C5H5)(Ph3P)2Ru (8a), (η5-C5H5)(Ph3P)2Os (8b), (η5-C5H5)(dppf)Ru (8c); bfc = 1′,1′′′-biferrocenyl, ((η5-C5H4)2Fe)2; dppf = 1,1′-bis(diphenyl)phosphanyl ferrocene, (η5-C5H4PPh2)2Fe) and (LnMC≡C)2bfc (LnM = (Ph3P)Au (6), (η5-C5H5)(Ph3P)2Ru (9a), (η5-C5H5)(Ph3P)2Os (9b), (η5-C5H5)(dppf)Ru (9c)) have been synthesized from (HC≡C)2bfc (4) with either (Ph3P)AuCl (5) in the presence of HNEt2/[CuI] (synthesis of 6) or LnMX (LnMX = (η5-C5H5)(Ph3P)2RuCl (7a); (η5-C5H5)(Ph3P)2OsBr (7b); (η5-C5H5)(dppf)RuCl (7c)) together with [H4N]PF6 and KOtBu (synthesis of 8 and 9), respectively. The structures of 6, 8b, 9a, 9b, and 9c in the solid state were determined by single-crystal X-ray structure analysis, showing unsymmetrical (8) or symmetrical geometries (6, 9), with almost eclipsed conformations or approximately midway positions between the fully eclipsed and the fully staggered conformation of the bfc cyclopen...

A new zinc(II) complex of pyrrolidinedithiocarbamate (PDTC), bis[(μ 2-pyrrolidinedithiocarbamato-S,S′)(pyrrolidinedithiocarbamato-S,S′)zinc(II)], [Zn2(PDTC)4] (1) has been prepared by reaction of ZnCl2 with ammonium pyrrolidinedithiocarbamate in 1 : 1 and 1 : 2 ratio, respectively. The complex has been characterized by IR, NMR and X-ray crystallography. Compound 1 crystallizes in the triclinic space group P 1 in the form of a centrosymmetric dimer. The solid-state structure contains two crystallographically equivalent Zn+2 centers in a tetrahedrally distorted ion sphere. A mixed-ligand complex, [Zn(PDTC)(MSC)]− (MSC = mercaptosuccinate) was also prepared but the structure of the resulting complex was found to be the same as 1, suggesting that the thiolate ligand was replaced on addition of PDTC.

Two new neutral, binuclear Cu II Cu II bis(oxamato) complexes with the formula [Cu 2 (opba)(pmdta)(MeOH)] · 1/2MeOH · dmf ( 3 ) and [Cu 2 (nabo)(pmdta)(MeOH)] ( 4 ), with opba = o -phenylene-bis(oxamato), nabo = 2,3-naphthalene-bis(oxamato), pmdta = N , N , N ′, N ″, N ″-pentamethyldiethylenetriamine and dmf = dimethylformamide have been synthesized and their crystal structures have been determined. The structure of 3 consists of dimeric [Cu 2 (opba)(pmdta)(MeOH)] entities, joined together by mutual intermolecular Cu⋯O contacts of the Cu 2+ ion of one [Cu(opba)] 2− complex fragment and one carboxylate atom of the oxamato group of a second [Cu(opba)] 2− complex fragment. The structure of 4 consists of neutral binuclear complexes joined together by hydrogen bonds and π–π interactions, giving rise to an unique supramolecular 1D-chain. The magnetic properties of 3 and 4 were studied by susceptibility measurements versus temperature. For the intramolecular J parameter, identical values of (−114 ± 2) cm −1 ( 3 ) and (−112 ± 2) cm −1 ( 4 ) were obtained.

Rigid-rod structured homobimetallic palladium complexes of type [{trans-(Me(O)CS-4-C6H4-C6H4)(Ph3P)2Pd}2(μ-N∩N)](OTf)2 (8a, μ-N∩N = 4,4′-bipyridine, bpy; 8b, μ-N∩N = C5H4N-CH N-N CH-C5H4N; 8c, μ-N∩N = C5H4N-CH CH-C6H4-CH CH-C5H4N; 8d, μ-N∩N = C5H4N-CH N-C6H4-N CH-C5H4N) were synthesized by the reaction of trans-[(Me(O)CS-4-C6H4-C6H4)(Ph3P)2Pd](OTf) (6) with 0.5 equivalents of N∩N (7a, N∩N = bpy; 7b, N∩N = C5H4N-CH N-N CH-C5H4N; 7c, N∩N = C5H4N-CH CH-C6H4-CH CH-C5H4N; 7d, N∩N = C5H4N-CH N-C6H4-N CH-C5H4N) in high yield. Complex 6 was accessible by the subsequent reaction of I-4-C6H4-C6H4-4′-SC(O)Me (2) with [(PPh3)4Pd] (3) to produce trans-[(I)(Me(O)CS-4-C6H4-C6H4)(Ph3P)2Pd] (4) which further reacted with AgOTf (5) to give 6. The structures of 4 and 8c in the solid state are reported. Most characteristic for these systems is the square-planer coordination geometry of palladium with trans-positioned PPh3 groups. This automatically positions the iodo ligand and the Me(O)CS-4-C6H4-C6H4 unit (complex 4) or the nitrogen donor atoms of the C5H4N-CH CH-C6H4-CH CH-C5H4N connectivity and the thio-acetyl group Me(O)CS-C6H4-C6H4 (complex 8c) trans to each other. In 8c a Pd–Pd separation of 20.156 A is typical. The electrochemical redox behavior of 2, 4 and 8 is discussed.

On the Reactivity of Titanocene Complexes [Ti(Cp′)2(η2-Me3SiC≡CSiMe3)] (Cp′ = Cp, Cp*) towards Benzenedicarboxylic Acids Titanocene complexes [Ti(Cp′)2(BTMSA)] (1a, Cp′ = Cp = η5-C5H5; 1b, Cp′ = Cp* = η5-C5Me5; BTMSA = Me3SiC≡CSiMe3) were found to react with iodine and methyl iodide yielding [Ti(Cp′)2(μ-I)2] (2a/b; a refers to Cp′ = Cp and b to Cp′ = Cp*), [Ti(Cp′)2I2] (3a/b) and [Ti(Cp′)2(Me)I] (4a/b), respectively. In contrast to 2a, complex 2b proved to be highly moisture sensitive yielding with cleavage of HCp* [{Ti(Cp*)I}2(μ-O)] (7). The corresponding reactions of 1a/b with p-cresol and thiophenol resulted in the formation of [Ti(Cp′)2{O(p-Tol)}2] (5a/b) and [Ti(Cp′)2(SPh)2] (6a/b), respectively. Reactions of 1a and 1b with 1,n-benzenedicarboxylic acids (n = 2–4) resulted in the formation of dinuclear titanium(III) complexes of the type [{Ti(Cp′)2}2{μ-1,n-(O2C)2C6H4}] (n = 2, 8a/b; n = 3, 9a/b; n = 4, 10a/b). All complexes were fully characterized analytically and spectroscopically. Furthermore, complexes 7, 8b, 9a·THF, 10a/b were also be characterized by single-crystal X-ray diffraction analyses.

Alkyloxy- and aryloxy-functionalized titanocenes of type [Ti](Cl)(OR) (R = Me (2), CH2PPh2 (3), CH2Fc (4), C6H5 (5), C6H4-4-C N (6), C6H4-4-NO2 (7), C6H4-4-Me (8), C6H4-4-OMe (9), C6H4-4-C(O)Me (10), C6H4-4-CO2Me (11), C6H4-3-NO2 (12); [Ti] = (η5-C5H4SiMe3)2Ti; Fc = (η5-C5H4)(η5-C5H5)Fe) were synthesized by the reaction of [Ti]Cl2 (1) with ROH in a 1:1 molar ratio and in presence of Et2NH. Diaryloxy-titanocenes (e.g., [Ti](OC6H4-4-NO2)2 (13)) are accessible, when the ratio of 1 and ROH is changed to 1:2. This synthesis methodology also allowed the preparation of dinuclear complexes of composition ([Ti](Cl))2(μ-OC6H4O) (14) and ([Ti](Cl)(μ-OC6H4-4))2 (15) by the reaction of 1 with hydroquinone or 1,1′-dihydroxybiphenyl in a 2:1 stoichiometry. Cyclic voltammetric studies show the characteristic [Ti(IV)/Ti(III)] reductions. It was found that the potentials of the alkyloxy titanocenes 2–4 do not differ, while for the aryloxy-titanocenes 5–15 the reduction potentials correlate linearly with the σp/m Hammett substituent constants showing a strong influence of the substituents on the electron density at titanium. The structures of titanocenes 4, 5, 9, and 11–13 in the solid state are reported. Typical for these organometallic sandwich compounds is a distorted tetrahedral coordination geometry around titanium with D1–Ti–D2 angles (D1, D2 = centroids of the cyclopentadienyl ligands) of ca. 130 °. In comparison to FcCH2O-functionalized 4, for the aryloxy-titanocenes 5, 9, and 11–13 a significant larger Ti–O–C angle was found confirming electronic interactions between the titanium atom and the appropriate aryl group.

The synthesis and reaction chemistry of heteromultimetallic transition-metal complexes are discussed. Complex [(η 2 -dppf)(η 5 -C5H5)Ru-C=C-C6H4-4-PPh 2 ] (3) [dppf = 1,1'-bis(diphenylphosphanyl)ferrocene], accessible by treating [(η 2 -dppf)(η 5 -C 5 H 5 )RuCl] (1) with equimolar amounts of HC≡C-C 6 H 4 -4-PPh 2 (2), gives on treatment with [(cod)RhCl] 2 (4), [(η 5 -C 5 Me 5 )RhCl 2 ] 2 (6), and [(tht)AuCl] (8) heterotrimetallic [(η 2 -dppf)(η 5 -C5H5)Ru-C≡C-C6H4-4-PPh 2 -{Rh}] [5, {Rh} = (cod)RhCl; 7, {Rh} = (η 5 -C 5 Me 5 )RhCl 2 ) and [(η 2 -dppf)(η 5 -C 5 H 5 )Ru-C≡C-C 6 H 4 -4-PPh2-AuCl] (9), respectively. Tetra-and even pentametallic heteronuclear complexes can be prepared by following consecutive reaction sequences: Treatment of 9 with HC≡CR {10a, R = C 5 H 4 N-4; lOb, R = C 6 H 4 -4-C=N; lOc, R = bpy (= 2,2'-bipyridyl-5-yl); 12a, R = bpy[-Re(CO) 3 Cl]} in the presence of HNEt 2 and [Cul] gave [(η 2 -dppf)(η 5 -C5H5)Ru-C≡C-C6H4-4-PPh2-Au-C≡CR] {11a, R = C 5 H 4 N-4; lib, R = C 6 H 4 -4-C≡N; 11c, R = bpy; 13, R = bpy-[Re(CO) 3 Cl]}. Compound 11c is the key starting material for complexes of higher nuclearity. Treatment of 11c with [(nbd)-Mo(CO) 4 ] (14) afforded heterotetrametallic {(η 2 -dppf)(η 5 -C5H5)Ru-C=C-C6H4-4-PPh2-Au-C≡C-bpy[Mo(CO)4]) (15), whereas with [{[Ti](μ-σ,π-C≡CSiMe 3 )2)M]X [16a, MX = Cu(N≡CMe)PF 6 ; 16b, MX = AgOClO 3 ] novel heteropentametallic [(η 2 -dppf)(η 5 -C5H5)Ru-C≡C-C6H4-4-PPh2-Au-C≡C-bpy({[Ti](μ-σ,π-C=CSiMe3)2)M)]X (17a, M = Cu, X = PF 6 ; 17b, M = Ag, X = ClO 4 ) is formed. The reaction of lla with [{[Ti](μ-σ,π-C=CSiMe3) 2 }Cu]OTf (16c) produced [(η 2 -dppf)-(η 5 -C 5 H 5 )Ru-C=C-C6H4-4-PPh2-Au-C=C-4-C5H4N({[Ti](μ-σ,π-C=CSiMe3)2)Cu)]OTf (18). The structures of 9, lib, 11c, and 12 in the solid state and the electrochemical behavior of selected complexes are also reported.

The applicability of the copper(I)-catalyzed click reaction of terminal trialkynes with triazides to the synthesis of cage-like triazole compounds was determined. A number of starting materials were prepared and several monotriazoles as well as macrocyclic bistriazoles were obtained from the triazide trialkyne reaction. Finally, a tristriazole macrobicyclic compound was synthesized from the previously formed triazole precursors.

The synthesis of a unique series of heteromultinuclear transition metal complexes with up to seven different metal atoms is reported by using consecutive synthesis methodologies including metathesis, dehydrohalogenation, and carbon−carbon cross-coupling reactions. In these compounds the metals Ti, Fe, Ru, Os, Re, Pt, and Cu are connected via carbon-rich bridging units comprising 1,3,5-triethynylbenzene and 2,2′-bipyridyl-5-yl. These molecules have been characterized by elemental analysis, IR and NMR spectroscopy, and ESI-TOF mass spectrometry. The main structural feature of these compounds is an unsymmetrical trans-configurated platinum(II) bis-acetylide unit. The structure of 1-(FcC≡C)-3-[(tBu2bpy)(CO)3ReC≡C]-5-[trans-(Ph3P)2(RcC≡C)PtC≡C]C6H3 (3) and 1,3-[(Ph3P)2(η5-C5H5)OsC≡C]2-5-[(CO)3(Cl)Re(bpyC≡C)]C6H3 (18) (Fc = (η5-C5H5)(η5-C5H4)Fe; Rc = (η5-C5H5)(η5-C5H4)Ru; tBu2bpy = 4,4′-di-tert-butyl-2,2′-bipyridyl; bpy = 2,2′-bipyridyl-5-yl) in the solid state is reported. Both compounds are characterized by t...

Synthesis, Structure, and EPR Spectroscopic Characterization of Titanocene Complexes with Dimethylmalonato Ligands The reaction of [TiCp2(BTMSA)] (1a, Cp = η5-C5H5, BTMSA = bis(trimethylsilyl)acetylene) with dimethylmalonic acid resulted in the formation of the titanium(III) complex [{TiCp2}2{μ-(O2C)2CMe2}] (2). Additionally, in an unprecedented case a small amount of the titanium(IV) complex [TiCp2{(O2C)2CMe2-κO}2] (3) was formed. The identity of complex 2 was confirmed by microanalysis, IR and EPR spectroscopic measurements. Single crystal X-ray diffraction analysis exhibited a dinuclear structure in which the titanium atoms are distorted tetrahedrally coordinated by two cyclopentadienyl ligands and a κ2O,O′ coordinated dimethylmalonato ligand that acts as bridging ligand, too. Magnetic measurements (μeff = 1.28/Ti, T = 295 K) and EPR investigations both of solutions of 2 in toluene at r.t. and of frozen solutions (T = 130 K) gave proof of a coupling between the two TiIII centres. The fine structure tensor exhibited rhombic symmetry (gx = 1.983, gy = 1.984, gz = 1.979, D = 101·10−4 cm−1, E = 6·10−4 cm−1). Using the equation of Francesconi a Ti···Ti separation of ca 6.3A was estimated that is in very good agreement with those obtained by X-ray crystallography (6.685(5) A). The single-crystal X-ray diffraction analysis of [TiCp2{(O2C)2CMe2-κO}2] (3) exhibited that the Ti centre of 3 is distorted tetrahedrally coordinated by two Cp ligands and two monocoordinated (κO) dimethylmalonato ligands.

The oxime-substituted NCN-pincer molecules HONCH-1-C6H3(CH2NMe2)2-3,5 (2a) and HONCH-4-C6H2(CH2NMe2)2-2,6-Br-1 (2b) were accessible by treatment of the benzaldehydes H(O)C-4-C6H3(CH2NMe2)2-3,5 (1a) and H(O)C-4-C6H2(CH2NMe2)2-2,6-Br-1 (1b) with an excess of hydroxylamine. In the solid state both compounds are forming polymers with intermolecular O–HN connectivities between the Me2NCH2 substituents and the oxime entity of further molecules of 2a and 2b, respectively. Characteristic for 2a and 2b is a helically arrangement involving a crystallographic 21 screw axis of the HONCH-1-C6H3(CH2NMe2)2-3,5 and HONCH-4-C6H2(CH2NMe2)2-2,6-Br-1 building blocks. The reaction of 2b with equimolar amounts of [Pd2(dba)3 · CHCl3] (3) (dba = dibenzylidene acetone) or [Pt(tol)2(SEt2)]2 (4) (tol = 4-tolyl) gave by an oxidative addition of the C–Br unit to M coordination polymers with a [(HONCH-4-C6H2(CH2NMe2)2-2,6)MBr] repeating unit (5: M = Pd, 6: M = Pt). Complexes 5 and 6 are in the solid state linear hydrogen-bridged polymers with O–HBr contacts between the oxime entities and the metal-bonded bromide.

The synthesis and reaction chemistry of heteromultimetallic transition-metal complexes by linking diverse metal-complex building blocks with multifunctional carbon-rich alkynyl-, benzene-, and bipyridyl-based bridging units is discussed. In context with this background, the preparation of [1-{(eta(2)-dppf)(eta(5)-C(5)H(5))RuC[triple bond]C}-3-{(tBu(2)bpy)(CO)(3)ReC[triple bond]C}-5-(PPh(2))C(6)H(3)] (10) (dppf = 1,1'-bis(diphenylphosphino)ferrocene; tBu(2)bpy = 4,4'-di-tert-butyl-2,2'-bipyridyl; Ph = phenyl) is described; this complex can react further, leading to the successful synthesis of heterometallic complexes of higher nuclearity. Heterotetrametallic transition-metal compounds were formed when 10 was reacted with [{(eta(5)-C(5)Me(5))RhCl(2)}(2)] (18), [(Et(2)S)(2)PtCl(2)] (20) or [(tht)AuC[triple bond]C-bpy] (24) (Me = methyl; Et = ethyl; tht = tetrahydrothiophene; bpy = 2,2'-bipyridyl-5-yl). Complexes [1-{(eta(2)-dppf)(eta(5)-C(5)H(5))RuC[triple bond]C}-3-{(tBu(2)bpy)(CO)(3)ReC[triple bond]C}-5-{PPh(2)RhCl(2)(eta(5)-C(5)Me(5))}C(6)H(3)] (19), [{1-[(eta(2)-dppf)(eta(5)-C(5)H(5))RuC[triple bond]C]-3-[(tBu(2)bpy)(CO)(3)ReC[triple bond]C]-5-(PPh(2))C(6)H(3)}(2)PtCl(2)] (21), and [1-{(eta(2)-dppf)(eta(5)-C(5)H(5))RuC[triple bond]C}-3-{(tBu(2)bpy)(CO)(3)ReC[triple bond]C}-5-{PPh(2)AuC[triple bond]C-bpy}C(6)H(3)] (25) were thereby obtained in good yield. After a prolonged time in solution, complex 25 undergoes a transmetallation reaction to produce [(tBu(2)bpy)(CO)(3)ReC[triple bond]C-bpy] (26). Moreover, the bipyridyl building block in 25 allowed the synthesis of Fe-Ru-Re-Au-Mo- (28) and Fe-Ru-Re-Au-Cu-Ti-based (30) assemblies on addition of [(nbd)Mo(CO)(4)] (27), (nbd = 1,5-norbornadiene), or [{[Ti](mu-sigma,pi-C[triple bond]CSiMe(3))(2)}Cu(N[triple bond]CMe)][PF(6)] (29) ([Ti] = (eta(5)-C(5)H(4)SiMe(3))(2)Ti) to 25. The identities of 5, 6, 8, 10-12, 14-16, 19, 21, 25, 26, 28, and 30 have been confirmed by elemental analysis and IR, (1)H, (13)C{(1)H}, and (31)P{(1)H} NMR spectroscopy. From selected samples ESI-TOF mass spectra were measured. The solid-state structures of 8, 12, 19 and 26 were additionally solved by single-crystal X-ray structure analysis, confirming the structural assignment made from spectroscopy.

Vibrational spectroscopies are shown to be highly sensitive to the structural modifications of paramagnetic mono- and trinuclear Cu(II)-bis(oxamato) complexes. The vibrational bands are assigned using density functional theory (DFT) calculations. Moreover, Raman spectroscopy investigations for different temperatures of thin films show that the onset of superexchange interactions at low temperatures does not involve a modification of the structural parameters. The influence of packing effects, however, on the magnetic properties is significant, as demonstrated by means of DFT using the broken symmetry approach.

A copper(I) complex, poly(chloridobis(imidazolidine-2-thione)thiocyanato dicopper(I)), [Cu2(Imt)2(SCN)Cl] n (1) (Imt = Imidazolidine-2-thione) has been prepared by the reaction of CuCl2 with imidazolidine-2-thione and potassium thiocyanate in the ratio of 1:1:2. Compound 1 crystallizes in the monoclinic space group P21/a in the form of a coordination polymer, consisting of 2D layers. The solid-state structure is composed of dinuclear units having each copper(I) ion tetrahedrally coordinated. These units aggregate through bridging Imt and thiocyanate leading to a supramolecular 2D-network. The title complex, poly(chloridobis(imidazolidine-2-thione)thiocyanato dicopper(I)), [Cu2(Imt)2(SCN)Cl] n (Imt = Imidazolidine-2-thione) was prepared by the reaction of CuCl2 with imidazolidine-2-thione and potassium thiocyanate in the ratio of 1:1:2. The crystal structure consists of dinuclear units having each copper(I) ion tetrahedrally coordinated. These units aggregate through bridging Imt and thiocyanate leading to a supramolecular 2D-network.

The formate copper(I) complex [(P(C6H2CH2NMe2-2)3)CuO2CH] (3) is accessible by the reaction of equimolar amounts of P(C6H2CH2NMe2-2)3 (1) with [CuO2CH] (2). When 3 is treated with HO2CH (4) or HO2CMe (6), molecules [(P(C6H2CH2NMe2-2)3)CuO2CH · 2HO2CH] (5) and [(P(C6H2CH2NMe2-2)3)CuO2CH · HO2CMe] (7), respectively, are formed. In 3, 5, and 7 the phosphane unit is acting as a tripodal PN2 ligand as it could be shown by 1H NMR spectroscopy. IR studies showed that the formate building block in 3 and in its solvated form in 5 and 7 is σ-bonded by one oxygen atom to Cu(I). The thermal decomposition behavior of 3 is discussed. The solid state structure of 5 is reported. The crystal structure consists of two chemical identical crystallographic independent molecules. In 5 a four-coordinated copper(I) ion is present with the P(C6H4CH2NMe2-2)3 ligand occupying three of the coordination sites, while the 4th site is occupied by the formate anion. One of the two formic acid molecules in 5 is thereby hydrogen-bonded to the CuO2CH entity, while the second HCO2H molecule forms a N⋯H hydrogen bridge with the non-coordinating ortho-substituent Me2NCH2.

Complexes of type { cis -[Pt](μ-σ,π-C CPh) 2 }AgX ( 3a , [Pt] = (bipy′)Pt, X = FBF 3 ; 3b , [Pt] = (bipy′)Pt, X = FPF 5 ; 3c , [Pt] = (bipy)Pt, X = OClO 3 ; 3d , [Pt] = (bipy′)Pt, X = BPh 4 ; bipy′ = 4,4′-dimethyl-2,2′-bipyridine; bipy = 2,2′-bipyridine) are accessible by combining cis -[Pt](C CPh) 2 ( 1a , [Pt] = (bipy′)Pt; 1b , [Pt] = (bipy)Pt) with equimolar amounts of [AgX] ( 2a , X = BF 4 ; 2b , X = PF 6 ; 2c , X = ClO 4 ; 2d , X = BPh 4 ). In 3a – 3d the platinum(II) and silver(I) ions are connected by σ- and π-bonded phenyl acetylide ligands. When the molar ratio of 1 and 2 is changed to 2:1 then trimetallic [{ cis -[Pt](μ-C CPh) 2 } 2 Ag]X ( 8a , [Pt] = (bipy)Pt, X = BF 4 ; 8b , [Pt] = (bipy′)Pt, X = PF 6 ; 8c , [Pt] = (bipy)Pt, X = BF 4 ) is produced. The solid state structure of 8a was determined by single X-ray crystal structure analysis. In 8a the silver(I) ion is embedded between two parallel oriented cis -[Pt](C CPh) 2 units. Within this structural arrangement the phenyl acetylides of individual [Pt](C CPh) 2 entities possess a μ-bridging position between Pt(II) and Ag(I). In addition, a very weak dative Pt → Ag interaction is found (Pt–Ag 2.8965(3) A). The respective silver carbon distances Ag–C α (2.548(7), 2.447(7) A) and Ag–C β (3.042(7), 2.799(8) A)(PtC α C β Ph) confirm this structural motif. Complexes 8a – 8c isomerize in solution to form trimetallic [{ cis -[Pt](μ-σ,π-C CPh) 2 } 2 Ag]X ( 9a , [Pt] = (bipy)Pt, X = BF 4 ; 9b , [Pt] = (bipy′)Pt, X = PF 6 ; 9c , [Pt] = (bipy)Pt, X = ClO 4 ). In the latter molecules the organometallic cation [{ cis -[Pt](μ-σ,π- C CPh) 2 } 2 Ag] + is set-up by two nearly orthogonal positioned [Pt](C CPh) 2 entities which are hold in close proximity by the group-11 metal ion. Within this assembly all four PhC C units are η 2 -coordinated to silver(I). A possible mechanism for the formation of 9 is presented.

H2[PtCl6]·6H2O in dried n-BuOH was found to react with an excess of bis(trimethylsilyl)acetylene (BTMSA), yielding the polymeric alkylidene-bridged platinum complex [{Pt2(μ-Cl)2{μ-C(OBu)Me}2}n] (3). Reactions of complex 3 with monodentate N, P, and S donors afforded dinuclear alkylidene-bridged complexes trans-[{PtCl(L)}2{μ-C(OBu)Me}2] (2-Mepy, 5a; 4-Mepy, 5b; 2-Brpy, 5c; PPh3, 6a; PPh2(4-py), 6b; tht, 7) (tht = tetrahydrothiophene) in yields between 51 and 92%. Owing to a syn and anti arrangement of the butoxy substituents, complexes 5−7 were obtained as diastereomeric mixtures. All comlexes were characterized by means of microanalysis and IR and NMR spectroscopy. Furthermore, X-ray diffraction analyses were performed for the complexes 5a−c and 6a,b, exhibiting central Pt2C2 rings with Pt−Pt distances between 2.573(1) and 2.681(1) A. Quantum chemical studies of 6a using the AIM theory gave evidence of the bonding in the Pt2C2 moiety in terms of four-centered bonds.