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THF Solution (thf + solution)
Selected AbstractsReductive Activation of tripod Metal Compounds: Identification of Intermediates and Preparative Application,EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 9 2008Jürgen Mautz Abstract [tripodCoCl2] {tripod = CH3C(CH2PPh2)3} when treated with KC8 in THF solution under an argon atmosphere produces a reactive species ["tripodCo0"] (A) which undergoes oxidative additions with stannanes, [tripodCo(H)2(SnBu3)] (4), formed, for example, by addition of Bu3SnH. Silanes, R3SiH, undergo the same type of reaction producing [tripodCo(H)2(SiR3)] (R = Et: 5a; R = Ph: 5b). The solid-state structures of all the compounds [tripodCo(H)2(ER3)] (E = Si, R = Ph; E = Sn, R = Ph, Bu) are rather similar. While they contain six-coordinate cobalt with the formal oxidation state of cobalt being +III the coordination geometry is not octahedral: the heteroelement E deviates from the position which it would have in octahedral coordination by around 40° while the other five ligands, three phosphorus and two hydrogen, have the expected interligand angles of around 90° and 180°, respectively. The deviation of the heteroelement E is such that it approaches the metal bonded hydrogen atoms leading to short H···E contacts of only about 190 pm (E = Si) and 230 pm (E = Sn), respectively. The generation of a reactive species ["tripodCo0"] (A) was transferred to the synthesis of a reactive tripodnickel(0) species by treating a THF solution of [(DME)NiBr2] with KC8 in the presence of tripod. This species reacts with two electron donor ligands L to produce the pseudo tetrahedral compounds [tripodNi(L)] {L = PPh3 (6), AsPh3 (7), cHexNC (8), tBuNC (9), C2H4 (10)}. The identity of the reactive nickel(0) species as unequivocally deduced from NMR experiments is [tripod4Ni3] (12). All compounds were characterised by the usual analytic techniques including X-ray analysis where applicable.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] The Transient Titanocene(II): Direct Synthesis from Solvated Titanium(II) Chloride and Cyclopentadienylsodium and Ensuing Interception with Diphenylacetylene as 1,1-Bis(cyclopentadienyl)-2,3,4,5-tetraphenyltitanacyclopentadiene,EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 1 2007John J. Eisch Abstract For the first time the unstable titanocene(II) has been directly synthesized by the Wilkinson metallocene approach, namely the interaction of a THF-soluble form of titanium(II) chloride with two equivalents of cyclopentadienylsodium in THF solution at 0°,25 °C. Because of the transient existence of the titanocene(II) thereby obtained, it could only be chemically trapped in high yield as 1,1-bis(cyclopentadienyl)-2,3,4,5-tetraphenyltitanacyclopentadiene by two equivalents of diphenylacetylene, if the acetylene was added at 25 °C, without removal of the by-product LiCl and NaCl. If the addition of the acetylene was delayed, in order to filter off the LiCl and NaCl from the reaction mixture, then no trace of the titanacyclopentadiene derivative was found upon hydrolytic workup. Instead, a significant portion of the acetylene was found to have undergone hydrotitanation. This finding is clear evidence that the titanocene(II) had undergone a precedented rearrangement to a known dimer having the structure of a titanocene(III) hydride with a fulvalene bridge between the titanium centers. We suggest that the LiCl and NaCl present in the unfiltered reaction mixture form a dichloro complex with titanocene(II) and thereby retard its dimerizing rearrangement to the titanocene(III) hydride. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Sodium Hydro(isothiocyanato)borates: Synthesis and StructuresEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 5 2004Heinrich Nöth Abstract Sodium thiocyanate reacts in THF solution with 18-crown-6 to give the molecular compound Na(18-crown-6)(THF)NCS (3) with the N atom of the NCS anion oriented towards Na+. The same reaction with 15-crown-5 yields the ion pair Na(15-crown-5)NCS (4). In contrast, Na(NCS)(py)4, obtained by treating a solution of Na(H3BNCS) in THF with pyridine, yields Na(py)4(NCS) (5), which has a chain structure with hexacoordinate Na atoms coordinated to five N atoms and an S atom. Na(NCS) in THF adds 1 equiv. of BH3 to give Na(H3BNCS)·nTHF. Addition of 18-crown-6 to this solution yields crystals of the salt [Na(18-crown-6)(THF)2][H3BNCS] (1), as shown by X-ray crystallography. Both the cation and the anion show site disorder. However, when 15-crown-5 is used for complexation, the salt [Na(15-crown-5)(THF)][H3BNCS] (2) can be isolated. Its anion shows an almost linear B,N,C,S unit. Only a mixture of (catecholato)(isothiocyanato)borates results on treating Na(NCS) in THF with catecholborane. However, the borate Na[catB(NCS)2] is readily formed by adding Na(NCS) to B -(isothiocyanato)catecholborane. Single crystals of this compound were obtained as the salt [Na(18-crown-6)(THF)2][catB(NCS)2] (6). On the other hand, the reaction of Na(NCS) with 9-borabicyclo[3.3.1]nonane (9-BBN) in THF yields Na[(9-BBN)NCS)]·nTHF, and, on addition of 18-crown-6, the complex [Na(18-crown-6)(THF)2][(9-BBN)NCS] was isolated. Suitable crystals for X-ray structure determination were, however, only obtained by crystallization from tetrahydropyran. This solvate has the rather unusual structure [Na(18-crown-6)(thp)2][{(9-BBN)NCS}2Na(thp)4] (8). The sodiate anion has an Na atom coordinated by two S and four O atoms. DFT calculations support these experimental results: The (isothiocyanato)borates are more stable than the thiocyanato isomers. For the latter a bent structure of the B,S,C,N unit with a B,S,C bond angle of 105.7° is predicted. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Synthesis of meso -Coumarin-Conjugated Porphyrins and Investigation of Their Luminescence PropertiesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 26 2007Weiying Lin Abstract A series of meso -coumarin-conjugated porphyrins 1a,e were designed and synthesized. Condensation of 4-chloroacetoacetate ethyl ester with m -cresol or resorcin afforded 4-chloromethylcoumarins, which were then hydrolyzed to give coumarin alcohols, followed by oxidation to provide coumarin aldehydes. The reaction of coumarin aldehydes with pyrrole under Adler or Lindsey conditions afforded the meso -coumarin-conjugated porphyrins 1a,e. Their UV/Vis absorption spectra and photoluminescent spectra were recorded both in dilute THF solution and as solid films. Analysis of the luminescence spectra indicate that the energy transfer from the coumarin substituents to the porphyrin core for 1a,e is more efficient in solid film than in solution, and the energy transfer from the coumarin substituent to the porphyrin core for 1d and 1e is more efficient than that of 1a, 1b and 1c in solid film. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Solution NMR and X-Ray Structural Studies on Phthalocyaninatoiron ComplexesHELVETICA CHIMICA ACTA, Issue 8 2006Ignacio Fernández Abstract The addition of primary amines as solubilizing reagents for phthalocyaninatoiron complexes is shown to afford six-coordinate bis(amine)phthalocyaninato complexes, i.e., [Fe(amine)2(pc)] 2 (amine,=,decan-1-amine) and 3 (amine,=,benzylamine), with the two new N-donors occupying the trans -axial positions. The new complexes were characterized by extensive NMR measurements in THF solution. For complex 3 with the benzylamine ligand, the solid-state structure was determined by X-ray diffraction methods. Complex 2 is sufficiently labile in THF solution to exchange one amine ligand against CO (gas) affording an equilibrium mixture containing [Fe(amine)(CO)(pc)] 4. [source] Synthesis of imidazole-containing conjugated polymers bearing phenol unit as side group and excited state intramolecular proton transfer-mediated fluorescenceJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 18 2009Koji Takagi Abstract Dibromobenzimidazole and dibromoimidazole bearing hydroxyl group-protected phenol unit (1 and 2) were prepared and they showed an intramolecular hydrogen bonding between ether oxygen and amino proton of imidazole. The palladium-catalyzed Suzuki coupling polymerization of 1 and 2 with benzene bis(boronic acid) derivatives gave soluble polymers (3 and 4), where the molecular weights were limited probably due to the coordination ability of imidazole to palladium metal. The phenol hydroxyl groups were subsequently deprotected using BBr3 to obtain 3, and 4,. From the 1H NMR spectra, the complete conversion to the hydroxyl group and the formation of another type of intramolecular hydrogen bonding between hydroxyl proton and imine nitrogen were confirmed. In the UV and PL spectra of 3, and 4,, the excited state intramolecular proton transfer (ESIPT) occurred to shift the emission spectra toward lower energy region compared to 3 and 4. Especially, the PL spectrum of 3, demonstrated large stokes shift (145 nm) in THF solution. The ESIPT-mediated fluorescence was influenced by the addition of methanol and trifluoroacetic acid, which inhibited the formation of intramolecular hydrogen bonding. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4822,4829, 2009 [source] Optical properties of a novel fluorene-based thermally stable conjugated polymer containing pyridine and unsymmetric carbazole groupsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 4 2009Der-Jang Liaw Abstract A new diiodo monomer containing heterocyclic pyridine and carbazole groups was synthesized via Chichibabin reaction and used in the preparation of a conjugated polymer via Suzuki coupling approach. The conjugated polymer was highly soluble in common organic solvents such as NMP, THF, dichloromethane, chloroform, toluene, xylene, and benzene at room temperature. The polymer had high glass transition temperature at 191 °C and Td10 at 434 °C in nitrogen atmosphere. The pristine polymer exhibited the UV,vis maximum absorption at 355 nm and shifted to 420 nm after protonation. The emission of the polymer in THF solution changed from the blue region with maximum peak at 400 nm to the yellow region with maximum peak at 540 nm after protonated by HCl, and the intensity of emission depended on the concentration of acid. The polymer also showed electrochromic behavior under applied voltage. The emission color of the polymer film changed from blue (435 nm) to yellow (570 nm) when 2.5 V bias voltage was applied. The polymer also exhibited write-once and read-many-times (WORM) polymer memory effect with tristable states. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 991,1002, 2009 [source] Carbazolevinylene-based polymers and model compounds with oxadiazole and triphenylamine segments: Synthesis, photophysics, and electroluminescenceJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 16 2008Panagiotis D. Vellis Abstract Two new soluble alternating carbazolevinylene-based polymers POXD and PTPA as well as the corresponding model compounds MOXD and MTPA were synthesized by Heck coupling. POXD and MOXD contained 2,5-diphenyloxadiazole segments, while PTPA and MTPA contained triphenylamine segments. All samples displayed high thermal stability. The polymers had higher glass transition temperature (Tg) than their corresponding model compounds. The samples showed absorption maximum at 364,403 nm with optical band gap of 2.62,2.82 eV. They emitted blue-green light with photoluminescence (PL) emission maximum at 450,501 nm and PL quantum yields in THF solution of 0.15,0.36. The absorption and the PL emission maxima of PTPA and MTPA were blue-shifted as compared to those of POXD and MOXD. The electroluminescence (EL) spectra of multilayered devices made using four materials exhibited bluish green emissions, which is well consistent with PL spectra. The EL devices made using poly(vinyl carbazole) doped with MOXD and MTPA as emitting materials showed luminances of 12.1 and 4.8 cd m,2. POXD and PTPA exhibited 25.4, and 96.3 cd m,2, respectively. The polymer containing the corresponding molecules in the repeating group showed much higher device performances. Additionally, POXD and MOXD exhibited better stability of external quantum efficiency (EQE) and luminous efficiency with current density resulting from enhancing the electron transporting properties. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 5592,5603, 2008 [source] Xanthene dye functionalized norbornenes for the use in ring opening metathesis polymerizationJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 7 2007Martina Sandholzer Abstract A convenient synthetic route towards polymerizable fluorescein, dicholorofluorescein, and eosin dyes is presented. Polymerizability was provided by linking 2-norbornene carboxylic acid, 11-bromo-undecyl ester to the dye's carboxylate functionality. Although the monomers bearing dichlorofluorescein and eosin were obtained in high yield, the related fluorescein bearing monomer could only be obtained in low yield. In the latter case, concurring etherification and esterification led to a product mixture of the desired carboxy modified monomer and a double substituted by-product. The dye-monomers were used successfully for the preparation of statistical copolymers with endo,exo -2,3-norbornene dicarboxylic acid dimethylester by ROMP. Absorption and luminescence characteristics and, in particular, the acid/base sensitive behavior of the parent dyes were preserved in the monomers and copolymers. The absorption and emission maxima in THF solution and in the solid state were red shifted in comparison to the aqueous samples of the parent dyes. Dye-copolymers exhibited good film forming properties. Solid state luminescence studies of the copolymers revealed an increasing sensitivity towards NEt3 vapor in the order fluorescein < dichlorofluorescein < eosin bearing copolymer. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1336,1348, 2007 [source] Synthesis of Polyanilines Bearing Optically Active SubstituentsMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 12 2006Hiromasa Goto Abstract Summary: Optically active polyanilines were prepared by an interfacial polymerization with (NH4)2S2O8 in a water/perchloric acid/chloroform system. The pristine polymer obtained in this way is in the oxidized (doped) form. The polymers display the mirror-image Cotton effect. The doping process in solution allows a change in the circular dichroism of the polymer. The procedure has great potential in the improved preparation of durable optoelectrical devices based on the good film-forming properties of chiral polymers. CD spectra of R - P2 (solid line) and S - P2 (dashed line) in 4.0,×,10,4M THF solution. [source] Luminescent Monomer and Poly(methacrylate) Containing 1,3,4-Oxadiazole and Stilbene Units: Synthesis and Optical PropertiesMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 14 2004John A. Mikroyannidis Abstract Summary: A monomer M as well as a poly(methacrylate) P carrying the same chromophore, that consists of 1,3,4-oxadiazole and stilbene units, were efficiently synthesized. They dissolved in common organic solvents such as THF, chloroform, dichloromethane, 1,1,2,2-tetrachloroethane and chlorobenzene. P showed a Tg value of 145,°C. Both M and P were stable up to approximately 300,°C and afforded anaerobic char yield of about 40% at 800,°C. Their optical properties were comparable. They emitted intense violet-blue light in THF solution with a PL maximum at 413 nm and a PL quantum yield of 0.29 for M and 0.73 for P. Thin films of them displayed optical band gap of 3.03 eV and blue-light emission with a PL maximum around 440 nm. The PL curves of both samples were progressively red-shifted with increasing the solvent polarity. The influence of the annealing on the PL emission spectrum of M and P thin films was investigated. [source] Pyrene-Functionalised, Alternating Copolyimide for Sensing Nitroaromatic CompoundsMACROMOLECULAR RAPID COMMUNICATIONS, Issue 6 2009Stefano Burattini Abstract A novel, pyrene-functionalised copolymer has been synthesised in a single step via imidisation of poly(maleic anhydride- alt -1-octadecene) with 1-pyrenemethylamine, and its potential for the detection of volatile nitro aromatic compounds (NACs) evaluated. The new copolymer forms complexes in solution with NACs such as 2,5-dinitrobenzonitrile, as shown by 1H NMR, UV-vis and fluorescence spectroscopy. Moreover, thin films of this copolymer, cast from THF solution, undergo almost instantaneous fluorescence quenching when exposed to the vapour of 2,5-dinitrobenzonitrile (a model for TNT) at ambient temperatures and pressures. [source] Stereoselective synthesis of (Z)-5-(Trideca-4-enyl)resorcinol and gibbilimbols A,DCHINESE JOURNAL OF CHEMISTRY, Issue 11 2004Ling Zhou Abstract (Z)-5,(Trideca-4-enyl)resorcinol (1) and gibbilimbols A,D (2,5) were synthesized in 47%-60% yields over 6 steps from commercially available starting materials. The Wittig reaction of various alkyl phosphonium bromides with appropriate aldehydes in the presence of potassium ten-butoxide (t -BuOK) in anhydrous THF solution at room temperature served as the key step, and the result showed that only (Z)-configuration olefins were formed by this procedure. The synthesis of the (Z)-5-(trideca-4-enyl)resorcinol (1) was reported for the first time. [source] Synthesis of Substituted Indenyl Lanthanide Chloride and Molecular Structure of [(C5H9C9H6) 2Yb (,-Cl) 2Li (Et2O)2]CHINESE JOURNAL OF CHEMISTRY, Issue 2 2003Cui Dong-Mei Abstract Reaction of anhydrous ytterbium trichlorides with 2 equiv. of cyclopentylindenyl lithium in THF solution, followed by removal of the solvent and crystallization of the product from diethyl ether, affords a crystal complex of the composition (C5H9C9H6)2Yb (,-Cl)2Li(Et2O)2. Crystallographic analysis shows that the ytterbium coordinated by two cyclopentylindenyl rings and lithium surrounded by two ether molecules are bridged by the two chlorine atoms and Yb, Li and two chlorine atoms form a plane. [source] Photophysical and electrochemical characterization of new poly(arylene vinylene) copolymers containing quinoline or bisquinoline segmentsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 13 2009John A. Mikroyannidis Abstract Four new fluorescent conjugated vinylene-copolymers incorporating quinoline or bisquinoline segments along the backbone were synthesized by Heck coupling. Three of them were fluorenevinylene-copolymers and contained quinoline (PQFV, PQFVT) or bisquinoline segments (PBQFV). One of them (PBQPV) was phenylenevinylene-copolymer and contained bisquinoline segments. All the copolymers were soluble in common organic solvents and had relatively low glass transition temperature (Tg = 50,56 °C for fluorenevinylenes and Tg < 25 °C for phenylenevinylene). In THF solutions, the quinoline-containing copolymers showed absorption maxima at 411,420 nm while the bisquinoline-containing ones exhibited maxima at 357,361 nm. The emission maxima of solutions were 465,490 nm. The copolymers showed high quantum yields up to 64%. The films exhibited absorption and emission maxima in the range of 371,437 nm and 480,521 nm, respectively. All copolymers revealed reversible reduction with electron affinity of 2.66,3.53 eV and irreversible oxidation scans with ionization potential of 5.39,5.53 eV. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3370,3379, 2009 [source] Stereoregular P(MMA)-clay nanocomposites by metallocene catalysts: In situ synthesis and stereocomplex formationJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 13 2007Wesley R. Mariott Abstract This contribution reports the synthesis and characterization of stereochemically controlled, as well as crystalline stereocomplex, P(MMA)-clay nanocomposites using metallocene complexes and alane-intercalated clay activators. The ligand elimination and exchange reactions involving Lewis acids E(C6F5)3 (E = Al, B) and an organically modified montmorillonite clay were employed to synthesize the alane-intercalated clay activators. When combined with dimethyl metallocenes of various symmetries, these clay activators brought about efficient MMA polymerizations leading to in situ polymerized, stereochemically controlled P(MMA)-intercalated clay nanocomposites. The most noticeable thermal property enhancement observed for the clay nanocomposite P(MMA), when compared with the pristine P(MMA) having similar molecular weight and stereomicrostructure, has a considerable increase in Tg (,10 °C). Mixing of dilute THF solutions of two diastereomeric nanocomposites in a 1:2 isotactic to syndiotactic ratio, followed by reprecipitation or crystallization procedures, yielded unique double-stranded helical stereocomplex P(MMA)-clay nanocomposites with a predominantly exfoliated clay morphology. Remarkably, the resulting crystalline stereocomplex P(MMA) matrix is resistant to the boiling-THF extraction and its clay nanocomposites exhibit high Tm of 201 to 210 °C. Furthermore, the stereocomplex P(MMA)-clay nanocomposite shows a one-step, narrow decomposition temperature window and a single, high maximum rate decomposition temperature of 377 °C. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2581,2592, 2007 [source] Synthesis of Upper Rim Functionalized Calixarene-Based Poly(norbornenes)MACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 9 2010Alaa S. Abd-El-Aziz Abstract A modified synthesis of 25-allyl-26,27,28-trihydroxycalix[4]arene is reported. This calix[4]arene was utilized to prepare calix[4]arenes containing norbornene and calix[4]arene containing azo dyes and norbornene on their upper rims. The calixarene monomers were reacted with Grubbs' second generation catalyst to give poly(norbornenes) containing calixarenes. The poly(norbornenes) were determined to possess molecular weights between 45,100 and 116,200 with PDIs between 1.4 and 1.9. Thermal analysis showed that the azo dye containing polymers were less thermally stable than the non-azo dye containing polymers with decompositions beginning at 140,°C and 395,°C, respectively. The azo dye containing polymers displayed ,max at 430,nm in THF solutions that underwent a bathochromic shift to 520,nm when acidified with HCl(g), due to the formation of the azonium ion. [source] Preparation and properties investigation of PMMA/silica composites derived from silicic acidPOLYMERS FOR ADVANCED TECHNOLOGIES, Issue 2 2009H. P. Fu Abstract Hybrid materials based on silicic acid and polymethyl methacrylate (PMMA) were prepared by in situ bulk polymerization of a silicic acid sol and MMA mixture. Silicic acid sol was obtained by tetrahydrofuran (THF) extraction of silicic acid from water. Silicic acid was prepared by hydrolysis and condensation of sodium silicate in the presence of 3.6,M HCl. As a comparative study, PMMA composites filled by silica particles, which were derived from calcining the silicic acid gel, were prepared by a comparable in situ polymerization. Each set of PMMA/silica composites was subjected to thermal and mechanical studies. Residual THF in PMMA/silicic acid composites impacted the properties of the polymer composites. With increase in silica content, the PMMA composites filled with silica particles showed improved thermal and mechanical properties, whereas a decrease in thermal stability and mechanical strength was found for PMMA composites filled with silicic acid dissolved in THF. With a better compatibility with polymer matrix, silicic acid sol shows better reinforcement than silica particles in PMMA films prepared via blending of the corresponding THF solutions. Copyright © 2008 John Wiley & Sons, Ltd. [source] 7Li, 31P, and 1H Pulsed Gradient Spin-Echo (PGSE) Diffusion NMR Spectroscopy and Ion Pairing: On the Temperature Dependence of the Ion Pairing in Li(CPh3), Fluorenyllithium, and Li[N(SiMe3)2] amongst Other SaltsCHEMISTRY - A EUROPEAN JOURNAL, Issue 5 2005Ignacio Fernández Abstract 7Li, 31P, and 1H variable-temperature pulsed gradient spin-echo (PGSE) diffusion methods have been used to study ion pairing and aggregation states for a range of lithium salts such as lithium halides, lithium carbanions, and a lithium amide in THF solutions. For trityllithium (2) and fluorenyllithium (9), it is shown that ion pairing is favored at 299 K but the ions are well separated at 155 K. For 2-lithio-1,3-dithiane (13) and lithium hexamethyldisilazane (LiHMDS 16), low-temperature data show that the ions remain together. For the dithio anion 13, a mononuclear species has been established, whereas for the lithium amide 16, the PGSE results allow two different aggregation states to be readily recognized. For the lithium halides LiX (X = Br, Cl, I) in THF, the 7Li PGSE data show that all three salts can be described as well-separated ions at ambient temperature. The solid state structure of trityllithium (2) is described and reveals a solvent-separated ion pair formed by a [Li(thf)4]+ ion and a bare triphenylmethide anion. [source] Preparation, Geometric and Electronic Structures of [Bi2Cu4(SPh)8(PPh3)4] with a Bi2 Dumbbell, [Bi4Ag3(SePh)6Cl3(PPh3)3]2 and [Bi4Ag3(SePh)6X3(PPhiPr2)3]2 (X = Cl, Br) with a Bi4 UnitEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 32 2008Heino Sommer Abstract BiBr3 and CuCl react with S(Ph)SiMe3 in thf solution in the presence of PPh3 to yield [BiCu2(SPh)3Br2(PPh3)3] (1). The reaction of 1 with 2 equiv. of NaSPh gives rise to [Bi2Cu4(SPh)8(PPh3)4] (2) containing a Bi2 dumbbell. In this paper we further report the synthesis and characterization of the new cluster complexes [Bi4Ag3(SePh)6Cl3(PPh3)3]2 (3) and[Bi4Ag3(SePh)6X3(PPhiPr2)3]2 [X = Cl (4), Br (5)]. In the surprisingly formed species 3,5 a formal charged Bi46+ unit is observed. Compounds 3,5 were prepared by the reaction of BiX3 (X = Cl, Br), AgStBu, Se(Ph)SiMe3 and phosphane (PPh3, PPhiPr2). The structures of the compounds were determined by single-crystal X-ray analysis. Additionally, theoretical investigations were preformed to rationalize the bonding situation in 2,5. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] | |||||||||||||