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The novel nitrosyl-bridged complex [W2Cp2(μ-PtBu2)(μ-κ:η-NO)(CO)(NO)](BAr4) [Ar = 3,5-C6H3(CF3)2] was prepared in a multistep procedure starting from the hydride [W2Cp2(μ-H)(μ-PtBu2)(CO)4] and involving the new complexes [W2Cp2(μ-PtBu2)(CO)4](BF4), [W2Cp2(μ-PtBu2)(CO)2(NO)2](BAr4), and [W2(μ-κ:η5-C5H4)Cp(μ-PtBu2)(CO)(NO)2] as intermediates, which follow from reactions with HBF4·OEt2, NO, and Me3NO·2H2O, respectively. The nitrosyl-bridged cation easily added chloride upon reaction with [N(PPh3)2]Cl, with concomitant NO rearrangement into the terminal coordination mode, to give [W2ClCp2(μ-PtBu2)(CO)(NO)2], and underwent N–O and W–W bond cleavages upon the addition of CNtBu to give the mononuclear phosphinoimido complex [WCp(NPtBu2)(CNtBu)2](BAr4). Another N–O bond cleavage was induced upon photochemical decarbonylation at 243 K, which gave the oxo- and phosphinito-bridged nitrido complex [W2Cp2(N)(μ-O)(μ-OPtBu2)(NO)](BAr4), likely resulting from a N–O bond cleavage step following decarbonylation.

The reaction of new dinuclear gold(I) organometallic complexes containing mesityl ligands and bridging bidentate phosphanes [Au2(mes)2(μ‐LL)] (LL=dppe: 1,2‐bis(diphenylphosphano)ethane 1 a, and water‐soluble dppy: 1,2‐bis(di‐3‐pyridylphosphano)ethane 1 b) with Ag+and Cu+lead to the formation of a family of heterometallic clusters with mesityl bridging ligands of the general formula [Au2M(μ‐mes)2(μ‐LL)][A] (M=Ag, A=ClO4−, LL=dppe 2 a, dppy 2 b; M=Ag, A=SO3CF3−, LL=dppe 3 a, dppy 3 b; M=Cu, A=PF6−, LL=dppe 4 a, dppy 4 b). The new compounds were characterized by different spectroscopic techniques and mass spectrometry The crystal structures of [Au2(mes)2(μ‐dppy)] (1 b) and [Au2Ag(μ‐mes)2(μ‐dppe)][SO3CF3] (3 a) were determined by a single‐crystal X‐ray diffraction study. 3 ain solid state is not a cyclic trinuclear Au2Ag derivative but it gives an open polymeric structure instead, with the {Au2(μ‐dppe)} fragments “linked” by {Ag(μ‐mes)2} units. The very short distances of 2.7559(6) Å (AuAg) and 2.9229(8) Å (AuAu) are indicative of gold–silver (metallophilic) and aurophilic interactions. A systematic study of their luminescence properties revealed that all compounds are brightly luminescent in solid state, at room temperature (RT) and at 77 K, or in frozen DMSO solutions with lifetimes in the microsecond range and probably due to the self‐aggregation of [Au2M(μ‐mes)2(μ‐LL)]+units (M=Ag or Cu; LL=dppe or dppy) into an extended chain structure, through AuAu and/or AuM metallophilic interactions, as that observed for 3 a. In solid state the heterometallic Au2M complexes with dppe (2 a–4 a) show a shift of emission maxima (from ca. 430 to the range of 520‐540 nm) as compared to the parent dinuclear organometallic product 1 awhile the complexes with dppy (2 b–4 b) display a more moderate shift (505 for 1 bto a max of 563 nm for 4 b). More importantly, compound [Au2Ag(μ‐mes)2(μ‐dppy)]ClO4(2 b) resulted luminescent in diluted DMSO solution at room temperature. Previously reported compound [Au2Cl2(μ‐LL)] (LL dppy 5 b) was also studied for comparative purposes. The antimicrobial activity of 1–5and Ag[A] (A=ClO4−, SO3CF3−) against Gram‐positive and Gram‐negative bacteria and yeast was evaluated. Most tested compounds displayed moderate to high antibacterial activity while heteronuclear Au2M derivatives with dppe (2 a–4 a) were the more active (minimum inhibitory concentration 10 to 1 μg mL−1). Compounds containing silver were ten times more active to Gram‐negative bacteria than the parent dinuclear compound 1 aor silver salts. Au2Ag compounds with dppy (2 b, 3 b) were also potent against fungi.

The counterion makes a difference: A square 2D array of cobalt citrate cubanes linked by bridging six‐coordinate cobalt atoms (see graphic) displays collective magnetic behavior, which changes with subtle differences in the crystalline surroundings. The magnetic properties of two solid modifications, both synthesized by using wet chemistry techniques, reveal two different relaxation processes in each system at low temperatures, each with its own timescale.

Chlorocarbon solvents(solv=CH2Cl2, CHCl3) are suggested to play an active role in the oxidative addition of halogens, X2(X=Cl, Br, I), to homoleptic d8perfluoromethyl and ‐phenyl platinum(II) species [Pt(RF)4]2−(RF=CF3, C6F5). The perfluoromethyl group, CF3, has been found to be considerably less prone to undergo reductive elimination processes, and is, therefore, more suitable for stabilizing organoplatinum(IV) derivatives (see scheme).

A series of vinylgold(I) complexes [Au(CR=CHR)L] (R = H, Me; L = PPh3, PPh2Me, PPhMe2) were prepared from the reaction of the Grignard reagents [MgBr(CR=CHR)] (R = H, Me) with the gold(I) phosphane complexes [AuCl(L)] (L = PPh3, PPh2Me, PPhMe2) at low temperature. The complexes were characterised by various spectroscopic techniques and, in the case of [Au(CMe=CHMe)(PPh3)], by a single-crystal X-ray structure determination. The gold–carbon bonds of these vinylgold(I) complexes are easily cleaved by acids and, in the presence of potassium permanganate, by species containing acidic protons. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

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Treatment of the polyfunctional ylide Ph3P=C(H)C(O)CH2COOEt (1) with the solvated complexes [M(C^∧X)(THF)2]ClO4 gave the O,O' derivatives [M(C^∧X)(Ph3PCH2C(O)=C(H)−C(=O)OEt-κ-O,O']ClO4 [M(C^∧X) = Pd(C6H4CH2NMe2) (2), Pd(CH2C9H6N) (3), Pd(NC5H4-2-C6H4) (4), Pd(NC13H8) (5), Pd[(S)−C6H4C(H)MeNMe2] (6), Pt[o-CH2C6H4P(o-tol)2] (7), Pd[o-CH2C6H4P(o-tol)2] (8), and Pd(C6F5)(SC4H8) (9)]. During the reaction, one proton of the methylene unit is transferred to the ylidic carbon, which is transformed into a phosphonium group generating the zwitterion [Ph3PCH2C(O)=C(H)−C(=O)OEt], which coordinates to the metal center as an O,O'-chelating ligand. Treatment of 1 with [AuCl(SC4H8)] or [Au(PPh3)(OCMe2)]ClO4 gave [AuCl{C(H)(PPh3)C(O)CH2COOEt}] (10) or [Au{C(H)(PPh3)C(O)CH2COOEt}(PPh3)]ClO4 (11), in which the ylide is C-bonded. The X-ray crystal structures of complexes 2a, 9 and 10 have been determined. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

Six pentafluorophenylplatinum(ii) complexes containing proton acceptor atoms (F) and pyridine-like aromatic ligands able to act as proton donors have been synthesized and characterized, with emphasis on the factors that mediate their supramolecular aggregation in the solid state—hydrogen bonds and π–π interactions. The crystal structure analyses of the mononuclear complexes cis-[Pt(C₆F₅)₂(napy)] (1), cis-[Pt(C₆F₅)₂(CH₂napy)] (3), cis-[Pt(C₆F₅)₂(2-ammpy)] (5), and cis-[Pt(C₆F₅)₂(2-bipym)] (6) reveal the influence of D–H⋯Pt and D–H⋯F (D = C, N) hydrogen bonding on the organization of molecules into stacks, which can be further interconnected to generate channels. The prevalence of hydrogen bonding over π–π interactions between aromatic rings in establishing the nature of the observed supramolecular aggregation is demonstrated.

Six pentafluorophenylplatinumii complexes containing proton acceptor atoms F and pyridine-like aromatic ligands able to act as proton donors have been synthesized and characterized, with emphasis on the factors that mediate their supramolecular aggregation in the solid state—hydrogen bonds and π–π interactions. The crystal structure analyses of the mononuclear complexes cis-PtC6F52napy 1, cis-PtC6F52CH2napy 3, cis-PtC6F522-ammpy 5, and cis-PtC6F522-bipym 6 reveal the influence of D–HPt and D–HF D C, N hydrogen bonding on the organization of molecules into stacks, which can be further interconnected to generate channels. The prevalence of hydrogen bonding over π–π interactions between aromatic rings in establishing the nature of the observed supramolecular aggregation is demonstrated.

The new hydride complexes Mo2Cp2µ-Hµ-PHRCO4 having bulky substituents R 2,4,6-C6H2tBu3 Mes, R 2,4,6-C6H2Me3 Mes have been prepared in good yield by addition of LiPHR to the triply bonded Mo2Cp2CO4 and further protonation of the resulting anionic phosphide complex Mo2Cp2µ-PHRCO4−. Protonation of the Mes compound with either HOEt22B3,5-C6H3CF324 or HBF4·OEt2gives the cationic phosphinidene complex Mo2Cp2µ-Hµ-PMesCO4in high yield. In contrast, protonation of the analogous hydride compounds with Mes or Cy substituents on phosphorus give the corresponding unsaturated tetracarbonyls Mo2Cp2µ-PHRCO4, which are unstable at room temperature and display a cisgeometry. Decomposition of the latter give the electron-precise pentacarbonyls Mo2Cp2µ-PHRµ-COCO4, also displaying a cisarrangement of the metal fragments. In the presence of BF4−as external anion, fluoride abstraction competes with carbonylation to yield the neutral fluorophosphide hydrides Mo2Cp2µ-Hµ-PFRCO4. Similar results were obtained in the protonation reactions of the hydride compounds having a Ph substituent on phosphorus. In that case, using HCl as protonation reagent gave the chloro-complex Mo2ClCp2µ-PHPhCO4 in good yield. The structures and dynamic behaviour of the new compounds are analyzed on the basis of solution IR and 1H, 31P, 19F and 13C NMR data as well as the X-ray studies carried out on Mo2Cp2µ-Hµ-PHMesCO4cisisomer, Mo2Cp2µ-Hµ-PFMesCO4transisomer, Mo2Cp2µ-PHCyµ-COCO4BF4 and Mo2ClCp2µ-PHPhCO4.

2-(Arylazo)pyrimidine (1) reacts with palladium chloride and gives Pd(aapm)Cl2 (2) which undergoes a palladium(II)-mediated novel carbon−nitrogen bond formation reaction of the aromatic amines to the ortho-C−H function of the pendant aryl ring in the coordinated 2-(arylazo)pyrimidine. The reactant, Pd(papm)Cl2 (2a) and the product, Pd(papm-N-C6H4-OCH3-p)Cl (5a) have been characterised by X-ray crystal structure. The coupled products exhibit low energy transitions (NIR region) unlike the parent complex, Pd(aapm)Cl2. The cyclic voltammogram shows an oxidation couple at positive potential to SCE. The EHMO calculation suggests that the spectral feature in Pd(aapm)Cl2 (2) is due to the MLCT [d(Pd)&rlarr2;π*(azo)] whereas in Pd(aapm-N-C6H4-X-p)Cl (3−6) the transition at the NIR region is due to the intravalence charge transfer (IVCT) transition. Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2005/2002/i01280_s.pdf or from the author.

The phosphanylthiol PPh(2-C6H4SH)2 reacts with the Ni^II and Pd^II complexes [MCl2L2] in the presence of NaOEt to give the mononuclear derivatives [M{PPh(C6H4S)2}L] [M = Ni, L = PPh3 (1), PPh2Me (2); M = Pd, L = PPh3 (3)]. The analogous reaction starting with complexes containing bidentate ligands [MX2(L-L)] produces different results depending on the ligand used. The complexes [M{PPh(C6H4S)2}(dppm)] [M = Ni (4), Pd (5)], with an unligated phosphorus atom in the diphosphane are obtained with bis(diphenylphosphanyl)methane (dppm), while the dinuclear complexes [M2(μ-dppe){PPh(C6H4S)2}] [M = Ni (6), Pd (7)] are isolated in the case of 1,2-bis(diphenylphosphanyl)ethane (dppe). With 1,10-phenanthroline (phen), the complexes [M{PPh(C6H4S)2}(phen)] [M = Ni (8), Pd (9)] are obtained, but when 2,2'-bipyridine is used the dinuclear compounds [M{PPh(C6H4S)2}]2 [M = Ni (10), Pd (11)] are isolated instead. Complexes 10 and 11, which can be obtained starting from NiCl2 or [PdCl2(NCPh)2] respectively, afford complexes 1−7 when treated with the respective phosphanes in the appropriate stoichiometries. The structures of 2, 7 and 10 have been confirmed by X-ray analysis.

The reaction of [Ru(acac)3] (acac=acetylacetonate) with molten 1,3‐diaminobenzene affords the crystalline monometallic compound [Ru(L1)(acac)2] (1: L1=N‐(3′‐aminophenyl)1,2‐(3‐amino)benzoquinone diimine) along with an unstable dimetallic compound [Ru2(μ‐L2)(acac)4] (2: L2=N‐4,6‐bis(3′‐aminophenyl)imino‐3,5‐diimino‐hex‐1‐ene). Compound 2transforms to a stable dimetallic compound [Ru2(μ‐L3)(acac)4] (3: L3=2‐amino‐6(3′‐aminophenyl)imino‐9‐imino‐phenazine) in boiling 2‐methoxyethanol. The above compounds are formed by ruthenium‐mediated oxidative di‐ or trimerization of the diamine with the formation of several new C−N bonds. The products have been thoroughly characterized. FAB mass spectra, along with other physicochemical data, were used for their formulations. The compounds 1, 2, and 3display intense peaks due to their parent molecular ions at m/z512, 916, and 914, respectively. Final characterization of complex 3was made by single‐crystal X‐ray structure determination. The structure of 3confirmed the formation of three new C−N bonds and the bridging ligand L3from 1,3‐diaminobenzene. The conversion, 2→3is an oxidative ring‐closure reaction, which is associated with dehydrogenation reactions. The monometallic compound 1, showed a reversible metal‐based anodic response at 0.35 V. On the other hand, both the compounds 2and 3showed a pair of well‐resolved metal‐based anodic oxidations, for which the separation between the two successive anodic responses were high (>0.4 V). In addition, all of them showed multiple cathodic responses that were in the range −1.0 to −2.0 V.

The reaction of [Ru(acac)3] (acac=acetylacetonate) with molten 1,3-diaminobenzene affords the crystalline monometallic compound [Ru(L¹)(acac)2] (1: L¹=N-(3'-aminophenyl)1,2-(3-amino)benzoquinone diimine) along with an unstable dimetallic compound [Ru2(μ-L²)(acac)4] (2: L²=N-4,6-bis(3'-aminophenyl)imino-3,5-diimino-hex-1-ene). Compound 2 transforms to a stable dimetallic compound [Ru2(μ-L³)(acac)4] (3: L³=2-amino-6(3'-aminophenyl)imino-9-imino-phenazine) in boiling 2-methoxyethanol. The above compounds are formed by ruthenium-mediated oxidative di- or trimerization of the diamine with the formation of several new C−N bonds. The products have been thoroughly characterized. FAB mass spectra, along with other physicochemical data, were used for their formulations. The compounds 1, 2, and 3 display intense peaks due to their parent molecular ions at m/z 512, 916, and 914, respectively. Final characterization of complex 3 was made by single-crystal X-ray structure determination. The structure of 3 confirmed the formation of three new C−N bonds and the bridging ligand L³ from 1,3-diaminobenzene. The conversion, 2→3 is an oxidative ring-closure reaction, which is associated with dehydrogenation reactions. The monometallic compound 1, showed a reversible metal-based anodic response at 0.35 V. On the other hand, both the compounds 2 and 3 showed a pair of well-resolved metal-based anodic oxidations, for which the separation between the two successive anodic responses were high (>0.4 V). In addition, all of them showed multiple cathodic responses that were in the range −1.0 to −2.0 V. Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2111/2001/f3292_s.pdf or from the author.

A family of dinuclear manganese(III/III) complexes [Mn2^III(μ-X)(μ-L)(Y)2](Z)2 (X = Cl, OMe, OEt; Y = H2O; Z = Cl) (6a−c) of a new μ-bis(tetradentate) ligand, H3L, derived from the stepwise Schiff base condensation of triethylenetetramine, acetylacetone, and salicylaldehyde has been reported for the first time. NMR spectral and single crystal X-ray structural characterizations of the ligand confirm the formation of a five-membered imidazolidine ring as a backbone to have a new type of doubly bridging binucleating ligand system. In methanol solutions both the Mn^IIIMn^IV/Mn^IIIMn^III and Mn^IIIMn^III/Mn^IIIMn^II couples are observable for the chloro-bridged complex with E1/2 in the range of +0.49 to −0.13 V vs. saturated calomel electrode (SCE). The calculation of the comproportionation constant (Kc) from the E1/2 values clearly point towards the role of the Mn−O(phenolate)−Mn core for thermodynamic stability of the parent dimanganese(III/III) complex.

Chiral saturated alanine- and glycine-derived 6-isopropyl-5-phenylmorpholin-2-ones 11 and 12 have been prepared and employed for the generation of carboxy-stabilized ylides in asymmetric 1,3-dipolar cycloaddition reactions under thermal conditions, with electron-deficient dipolarophiles bearing double and triple bonds. The cycloadducts are obtained with high stereocontrol and mainly with endo selectivity, and can be used for the synthesis of highly substituted enantiomerically pure prolines.

The reactivity of cis-[Pt(C&z.tbd;CR)₂(COD)] (R = Bu^t, Ph) and cis/trans-[Pt(C₆F₅)₂(tht)₂] towards PPh₂C&z.tbd;CPPh₂ (dppa) in several molar ratios has been explored. Treatment of cis-[Pt(C&z.tbd;CR)₂(COD)] with 1 equiv. of dppa leads to novel alkynyl Pt(II) dimers [Pt₂(C&z.tbd;CR)₄(μ-dppa)₂] (R = Bu^t 1, Ph 2) with a double dppa-bridged system. However, the reactions with 2 equiv. of dppa only give mixtures of 1 or 2 and the expected cis-[Pt(C&z.tbd;CR)₂(dppa-κP)₂] (R = Bu^t 3, Ph 4). The analogous reactions using cis- or trans-[Pt(C₆F₅)₂(tht)₂] (tht = tetrahydrothiophene) as precursors afford, in 1 ∶ 1 molar ratio, the homologous pentafluorophenyl–bis(μ-dppa) diplatinum species [Pt₂(C₆F₅)₄(μ-dppa)₂] 5 or the polymer trans-[Pt(C₆F₅)₂(μ-dppa)]_n 7 and, in 1 ∶ 2 molar ratio, the mononuclear cis- or trans-[Pt(C₆F₅)₂(dppa-κP)₂] (6, 8) derivatives. The molecular structure of 5 has been confirmed by X-ray diffraction. Furthermore, [Pt₂(C&z.tbd;CR)₄(μ-dppa)₂] 1 and 2 react with 2 equiv. of cis-[Pt(C₆F₅)₂(thf )₂] to afford the tetranuclear bis(μ-alkynyl)bis(μ-dppa) platinum complexes [(C₆F₅)₂Pt(μ-C&z.tbd;CR)₂Pt(μ-dppa)]₂ (R = Bu^t 9, Ph 10). However, a mixture of 9/10 and [(RC&z.tbd;C)₂Pt(μ-dppa)₂Pt(μ-C&z.tbd;CR)₂Pt(C₆F₅)₂] (R = Bu^t 11, Ph 12) is observed if the reactions are carried out in 1 ∶ 1 molar ratios. Finally, dinuclear P-bonded mono μ-dppa complexes of type Q₂[cis-{Pt(C₆F₅)₂X}₂(μ-dppa)] [Q = NBu₄, X = C₆F₅ 13, X = Cl 14; Q = PMePh₃, X = C&z.tbd;CPh 15 (X-ray)] have also been prepared starting from the appropriate precursors and dppa.

The reaction of the epoxysteroids 1and 4, derived from estrone and cholestanone, respectively, with an excess of lithium and a catalytic amount of DTBB (7 mol%) in THF at −78°C, leads to the formation of the corresponding β-oxido-functionalised organolithium intermediates 2and 5, respectively, which, by reaction with different electrophiles [H2O, D2O, PhCHO, Me2CO, Et2CO, (CH2)5CO, CO2] at −78°C to room temperature, afford, after hydrolysis with water, enantiomerically pure compounds 3and 6, respectively. The stereochemistry of all these compounds was unambiguously determined by correlation with X-ray data for compound 3dand by comparison with the known compound 6a.

Schon bei Raumtemperaturgelingt die hochdiastereoselektive Alkylierung der neuen cyclischen chiralen Alaninesterderivate (6R)‐1mit K2CO3als Base unter Fest‐Flüssig‐Phasentransferkatalyse oder Pd‐katalysiert unter Neutralbedingungen. Die Produkte (3S,6R)‐2lassen sich leicht hydrolysieren, wobei (S)‐α‐Methyl‐α‐aminosäuren entstehen.

The understanding of the hydrogen bond, an interaction that appears in diverse environments and exercises widely varying functions, continues to expand with the report of a neutron diffraction analysis of a complex displaying an OH⋅⋅⋅Pt hydrogen bond with unligated water as the donor. What is known about hydrogen bonding so far provides a broad context for this new result.

Neue Erkenntnisse über die Wasserstoffbrücke– eine Wechselwirkung, die in unterschiedlichen Umgebungen auftritt und verschiedenste Funktionen hat – wurden aus einer Neutronenbeugungsanalyse eines Komplexes, der eine O‐H⋅⋅⋅Pt‐Brücke mit unligiertem Wasser als Donor enthält, gewonnen. Unser bisheriges Wissen über Wasserstoffbrücken bietet einen breiten Hintergrund für die Einordnung dieses neuen Befundes.

A silver(I) coordination polymer containing 1,3,5-triaza-7-phosphaadamantane (PTA) in an unprecedented bridging, tridentate P,N,N′-coordination mode is formed by the reaction of PTA with AgNO3 in water. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

At room temperature alreadyhighly diastereoselective alkylation of the new, cyclic, chiral alanine ester derivatives (6R)-1can been achieved with either K2CO3as base under solid–liquid phase-transfer catalysis or Pd catalysis unter neutral conditions. The products (3S,6R)-2can be easily hydrolyzed to form (S)-a-methyl a-amino acids.

The very unusual complex [Pt(C&z.tbd6;CBu^t)₂(PPh₂O)₂Li₂(μ-H₂O)(Me₂CO)₂]₂ 2 is obtained by the reaction of ‘Li₂[Pt(C&z.tbd6;CBu^t)₄]’ with an excess of PPh₂H in acetone–ethanol and possesses an unusual linear chain of four Li atoms sandwiched between two square planar dianionic units trans-⁻OPPh₂{Pt(C&z.tbd6;CBu^t)₂}PPh₂O⁻, to which it is bound through μ₃-PPh₂O⁻ bridging ligands.

The synthesis and crystal structure of a square cyano-bridged compound with terminal cyano ligands are presented together with a discussion of the influence of H₂O molecules on the stability of the terminal cyanides and therefore on the discrete nature of the compound.

The reaction of [Pd₂(CH₂C₆H₄P(o-tolyl)₂-κC,P)₂(μ-3,5-dmpz)₂] (1) with AgClO₄ renders [{Pd₂(CH₂C₆H₄P(o-tolyl)₂-κC,P)₂(μ₃-3,5-dmpz-N,N',C⁴)₂Ag(η²-μ-ClO₄)}₂] (2), a palladium–silver derivative displaying an unprecedented dmpz bridging ligand η¹ bonded to the Ag centers, involving only the C⁴ atom of each dmpz ligand.

Aqueous chemistryhas produced an anionic square net of cobalt citrate cubane single molecule magnets (SMMs) interleaved with a secondary magnetic network of bridging octahedrally coordinated CoII. The magnetic response of this system, which varies with a change in its solid environment, suggests novel possibilities for magnetically active SMM polymers, accessible through wet chemistry. For more details, see the Communication by L. R. Falvello and F. Palacio et al. on page 2818 ff.

Synthesis of a novel hexametallic compound, [{(bpy)₂Ru(biim)}₄Cu₂](ClO₄)₄, 3 (bpy = 2,2'-bipyridine and biim = 2,2'-biimidazolate dianion) from a monometallic complex, [(bpy)₂Ru(biim)] and hydrated Cu(ClO₄)₂ is described. The X-ray structure consists of four octahedral ruthenium(ii) centers arranged around a bimetallic Cu₂-core. The four octahedral [(bpy)₂Ru(biim)] units arranged around the Cu₂-moiety that resulted in a propeller shape arrangement. The results of cryomagnetic measurements on the di-copper complex indicate that the two Cu(ii) ions are coupled antiferromagnetically through the two bridging biim ligands. The EPR spectrum of the complex showed a typical axial spectrum. Optical spectra and redox properties of 3 are reported. An intense absorption at 525 nm is assigned as Ru(dπ) → π*(bpy) transition.

Synthesis of a novel hexametallic compound, bpy2Rubiim4Cu2ClO44, 3bpy 2,2′-bipyridine and biim 2,2′-biimidazolate dianion from a monometallic complex, bpy2Rubiim and hydrated CuClO42is described. The X-ray structure consists of four octahedral rutheniumii centers arranged around a bimetallic Cu2-core. The four octahedral bpy2Rubiim units arranged around the Cu2-moiety that resulted in a propeller shape arrangement. The results of cryomagnetic measurements on the di-copper complex indicate that the two Cuii ions are coupled antiferromagnetically through the two bridging biim ligands. The EPR spectrum of the complex showed a typical axial spectrum. Optical spectra and redox properties of 3are reported. An intense absorption at 525 nm is assigned as Rudπ → πbpy transition.

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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.