Francesc Teixidor

Publications (117)557.16 Total impact

• Article: A Versatile Methodology for the Controlled Synthesis of Photoluminescent High-Boron-Content Dendrimers.

  Arántzazu González-Campo, Albert Ferrer-Ugalde, Clara Viñas, Francesc Teixidor, Reijo Sillanpää, Jesús Rodríguez-Romero, Rosa Santillan, Norberto Farfán, Rosario Núñez
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  ABSTRACT: Fluorescent star-shaped molecules and dendrimers with a 1,3,5-triphenylbenzene moiety as the core and 3 or 9 carborane derivatives at the periphery, have been prepared in very good yields by following different approaches. One procedure relies on the nucleophilic substitution of Br groups in 1,3,5-tris(4-(3-bromopropoxy)phenyl)benzene with the monolithium salts of methyl and phenyl-o-carborane. The second method is the hydrosilylation reactions on the peripheral allyl ether functions of 1,3,5-tris(4-allyloxy-phenyl)benzene and 1,3,5-tris(4-(3,4,5-trisallyloxybenzyloxy)phenyl)benzene with suitable carboranyl-silanes to produce different generations of dendrimers decorated with carboranyl fragments. This approach is very versatile and allows one to introduce long spacers between the fluorescent cores and the boron clusters, as well as to obtain a high loading of boron clusters. The removal of one boron atom from each cluster leads to high-boron-content water-soluble macromolecules. Thermogravimetric analyses show a higher thermal stability for the three-functionalized compounds than for those containing 9 clusters. All compounds exhibit photoluminescent properties at room temperature under ultraviolet irradiation with high quantum yields; these depend on the nature of the cluster and the substituent on the Ccluster . Cyclic voltammetry indicates that there is no electronic communication between the core and the peripheral carboranyl fragments. Due to the high boron content of these molecules, we currently focus our research on their biocompatibility, biodistribution in cells cultures, and potential applications for boron neutron capture therapy (BNCT).
  Chemistry 03/2013; · 5.93 Impact Factor
• Article: A water soluble Mn(ii) polymer with aqua metal bridges.

  Mònica Fontanet, Montserrat Rodríguez, Isabel Romero, Xavier Fontrodona, Francesc Teixidor, Clara Viñas, Núria Aliaga-Alcalde, Pavel Matějíček
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  ABSTRACT: The first water soluble and crystallographically determined polynuclear Mn(ii) complex, with water molecules bridging every two Mn centers, is reported. This is an unusual feature in 1D oligomer Mn(ii) compounds with a nuclearity higher than 2. The polymer structure is largely preserved in water.
  Dalton Transactions 02/2013; · 3.84 Impact Factor
• Article: Methods to produce B-C, B-P, B-N and B-S bonds in boron clusters.

  David Olid, Rosario Núñez, Clara Viñas, Francesc Teixidor
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  ABSTRACT: Boranes, heteroboranes and metallacarboranes, all named as boron clusters, offer an alternative to typical organic molecules or organic molecular materials. Carbon and boron share the important property of self-catenation thus these elements can produce individually large and sophisticated molecules. Boron clusters and organic molecules display electronic, physical, chemical and geometrical characteristics manifestly different. These differences highlight the complementarity of organic molecules and boron clusters, and therefore the feasibility or necessity to produce hybrid molecules incorporating both types of fragments. To join these two types of fragments, or alternatively these two types of molecular compounds, tools are needed. In this review the current methods of producing boron clusters with carbon, B-C, nitrogen, B-N, phosphorus, B-P and sulphur bonds, B-S, are indicated. As there are many existing borane clusters of different sizes, heteroboranes and metallacarboranes, the revision of methods to generate the B-C, B-P, B-S, and B-N bonds has been restricted to the most widely used boron clusters; [B(12)H(12)](2-), dianionic and an example of a borane, 1,2-C(2)B(10)H(12), neutral and an example of a heteroborane, and [Co(C(2)B(9)H(11))(2)](-), monoanionic and an example of a metallacarborane.
  Chemical Society Reviews 01/2013; · 28.76 Impact Factor
• Source

  Available from: Clara Viñas

  Article: Boron and carbon: Antagonistic or complementary? Proposal for a simple prototype of a molecular clutch or molecular switch*

  Francesc Teixidor, Clara Viñas
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  ABSTRACT: Boron and carbon, either in elemental form or when combined, are structurally very different. They are indeed complementary, and the weaknesses of one can be complemented by the strengths of the other, and vice versa. The structural complementarity can be readily observed in the shape of [X n H n ] y– (X = C or B) compounds. One visualization of this com-plementarity can be found by comparing the most popular carbon and boron organometallic sandwich molecules, [Fe(C 5 H 5) 2 ] and [3,3'-Co(1,2-C 2 B 9 H 11) 2 ] – . Both obey the 18e – rule, and in both the metal is η 5 coordinated by two pentagonal faces. However, for [Fe(C 5 H 5) 2 ], the first ring of atoms outside the pentagonal face is coplanar with the coordinating face, whereas for [3,3'-Co(1,2-C 2 B 9 H 11) 2 ] – the substituents are out of the coordinating face fea-turing a canopy shading the metal. Taking advantage of this feature, [3,3'-Co(1,2-C 2 B 9 H 11) 2 ] – can be a well-performing molecular clutch electrochemically driven. When it is engaged, the beams of the upper [7,8-C 2 B 9 H 11 ] 2– ligand in [3,3'-Co(1,2-C 2 B 9 H 11) 2 ] – mesh the beams of the lower [7,8-C 2 B 9 H 11 ] 2– . This occurs when the molecular friction disk, the Co, is as Co 3+ . When Co 3+ is reduced to Co 2+ , its radius is elongated, and both sets of beams are unmeshed allowing for a more free rotation, or molecular clutch disengagement. Keywords: boron and carbon; carbon and boron; molecular clutches; molecular devices. COVALENT BORON AND CARBON Boron is the neighbor element to carbon in the periodic table, both displaying the highest tendency to self-catenate. However, whereas carbon tends to have four connections when it self-catenates, boron tends to have more than four. In this regard, geometrical structures with triangular faces are commonly observed with boron hydrides. Noncombined boron exists in four major polymorphs: α, β, γ, and T; in all of them the B 12 icosahedron exists. This evidences the tendency of catenated boron atoms to fold to produce concave structures and contrasts with carbon. Therefore, getting the same structures in boron and carbon is highly unlikely. Carbon produces extended flat surfaces such as these found in graphite or in grapheme, which cannot be generated with boron. On the contrary, boron tends to produce com-pact polyhedral structures that cannot be made with carbon. Therefore, from the structural point of view boron and carbon are complementary, and this complementarity stretches beyond geometrical
  Pure Appl. Chem. 10/2012; 84:11-15.
• Article: Li(+) -mediated bc cross-coupling.

  David Olid, Clara Viñas, Francesc Teixidor
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  ABSTRACT: Easy as A, BC: BC cross-coupling on [3,3'-Co(8-I-1,2-C(2) B(9) H(10) )(1',2'-C(2) B(9) H(11) )](-) , [1](-) , the best specimen of metallacarboranes, is easily produced in a reaction mediated by Li(+) in the absence of a transition-metal catalyst. Pure RLi or a mixture of Li reagents (tBuLi+RLi) is adequate to produce the BC bond. Notably, a threshold of RLi (or tBuLi+RLi)/[1](-) , 2:1, is required to initiate the BC coupling, which acts, at least in part, as a source of soluble Li(+) .
  Chemistry 09/2012; 18(41):12936-40. · 5.93 Impact Factor
• Source

  Available from: Detlef Gabel

  Article: From an Icosahedron to a Plane: Flattening Dodecaiodo-dodecaborate by Successive Stripping of Iodine.

  Pau Farràs, Nina Vankova, Lei Liu Zeonjuk, Jonas Warneke, Thomas Dülcks, Thomas Heine, Clara Viñas, Francesc Teixidor, Detlef Gabel
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  ABSTRACT: It has been shown by electrospray ionization-ion-trap mass spectrometry that B(12) I(12) (2-) converts to an intact B(12) cluster as a result of successive stripping of single iodine radicals or ions. Herein, the structure and stability of all intermediate B(12) I(n) (-) species (n=11 to 1) determined by means of first-principles calculations are reported. The initial predominant loss of an iodine radical occurs most probably via the triplet state of B(12) I(12) (2-) , and the reaction path for loss of an iodide ion from the singlet state crosses that from the triplet state. Experimentally, the boron clusters resulting from B(12) I(12) (2-) through loss of either iodide or iodine occur at the same excitation energy in the ion trap. It is shown that the icosahedral B(12) unit commonly observed in dodecaborate compounds is destabilized while losing iodine. The boron framework opens to nonicosahedral structures with five to seven iodine atoms left. The temperature of the ions has a considerable influence on the relative stability near the opening of the clusters. The most stable structures with five to seven iodine atoms are neither planar nor icosahedral.
  Chemistry 09/2012; 18(41):13208-12. · 5.93 Impact Factor
• Article: Influential role of ethereal solvent on organolithium compounds: the case of carboranyllithium.

  Adrian-Radu Popescu, Ana Daniela Musteti, Albert Ferrer-Ugalde, Clara Viñas, Rosario Núñez, Francesc Teixidor
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  ABSTRACT: The influence of ethereal solvents (diethyl ether (Et(2)O), tetrahydrofuran (THF) or dimethoxyethane (DME)) on the formation of organolithiated compounds has been studied on the 1,2-C(2)B(10)H(12) platform. This platform is very attractive because it contains two C(c)-H adjacent units ready to be lithiated. On would expect that the closeness of both C(c)-H units would induce a higher resistance of the second C(c)-H unit being lithiated following the first lithiation. However, this is not the case, which makes 1,2-C(2)B(10)H(12) attractive to get a better understanding of the ethereal solvent influence on the lithiation process. The formation of carboranyl disubstituted species has been attributed to the existence of an equilibrium in which the carboranyl monolithiated species disproportionates into dilithium carborane and pristine carborane. The way Li(+) binds to C(c) in the carboranyl fragment and how the solvent stabilizes such a binding is paramount to drive the reaction to the generation of mono- and disubstituted carboranes. In fact, the proportion of mono- and disubstituted species is a consequence of the formation of contact ion pairs and, to a lesser extent, of separated ion pairs in ethereal solvents. All ethereal solvents generate contact ion pairs in which a large degree of covalent C(c)-Li(solvent) bonding can be assumed, according to experimental and theoretical data. Furthermore, Et(2)O tends to produce carboranyllitium ion pairs with a higher degree of contact ion pairs than THF or DME. It has been determined that for a high-yield preparation of monosubstituted 1-R-1,2-C(2)B(10)H(11), in C(c)-R (R=C, S or P) coupling reactions, the reagent type defines which is the most appropriate ethereal solvent. In reactions in which a halide is generated, as with ClPPh(2) or BrCH(2) CH=CH(2), Et(2)O appears to produce the highest degree of monosubstitution. In other situations, such as with S(8), or when no halide is generated, THF or DME facilitate the largest degree of monosubstitution. It has been shown that upon the self reaction of Li[1,2-C(2)B(10)H(11)] to produce [LiC(4)B(20)H(22)](-) the nucleophilicity of the carboranyllithium can even be further enhanced, beyond the ethereal solvent, by synergism with halide salts. The mediation of Li(+) in producing isomerizations on allyl substituents has also been demonstrated, as Et(2)O does not tend to induce isomerization, whereas THF or DME produces the propenyl isomer. The results presented here most probably can be extended to other molecular types to interpret the Li(+) mediation in C-C or other C-X coupling reactions.
  Chemistry 03/2012; 18(11):3174-84. · 5.93 Impact Factor
• Article: Metallacarboranes and their interactions: theoretical insights and their applicability.

  Pau Farràs, Emilio J Juárez-Pérez, Martin Lepšík, Rafael Luque, Rosario Núñez, Francesc Teixidor
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  ABSTRACT: This tutorial review will deal with the study of metallacarboranes and their interactions with other molecules from a theoretical point of view. This contribution is devoted to guide experimental chemists through calculations that some years ago were reserved to theoretical specialists. The widespread availability of fast computers enables nowadays studies of complex compounds (e.g. metallacarboranes) from different perspectives including simulation of NMR, infrared or Raman spectra and calculation of other properties such as atomic charges or inter-/intramolecular interactions. The insights gained on the basis of theoretical calculations are crucial for either finding novel or improving existing applications of metallacarboranes. For example, in the case of enzyme inhibitors, the interactions of the metallacarboranes with the surrounding protein and how the interaction affects the efficiency are difficult problems to study experimentally. The use of theoretical tools can provide a detailed understanding of the physico-chemical basis of the interactions and thus offers a chance to control the overall process.
  Chemical Society Reviews 02/2012; 41(9):3445-63. · 28.76 Impact Factor
• Article: Chelation of a proton by oxidized diphosphines

  Adrian-Radu Popescu, Isabel Rojo, Francesc Teixidor, Reijo Sillanpää, Mikko M Hänninen, Clara Viñas
  Journal of Organometallic Chemistry 01/2012; 721–722:124 - 129. · 2.38 Impact Factor
• Article: Mercaptocarborane-Capped Gold Nanoparticles: Electron Pools and Ion Traps with Switchable Hydrophilicity

  Ana M. Cioran, Ana D. Musteti, Francesc Teixidor, Željka Krpetić, Ian A. Prior, Qian He, Christopher J. Kiely, Mathias Brust, Clara Viñas
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  ABSTRACT: A simple single-phase method for the preparation of ca. 2 nm gold nanoparticles capped with mercaptocarborane ligands is introduced. The resultant monolayer protected clusters (MPCs) exhibit redox-dependent solubility and readily phase transfer between water and nonpolar solvents depending on the electronic and ionic charge stored in the metal core and in the ligand shell, respectively. The particles and their properties have been characterized by high angle annular dark field imaging in a scanning transmission electron microscope, elemental analysis, centrifugal particle sizing, UV–vis and FTIR spectroscopy, and thermogravimetric analysis and by 1H, 11B, and 7Li NMR spectroscopy. Cellular uptake of the MPCs by HeLa cells has been studied by TEM, and the subsequent generation of reactive oxygen species inside the cells has been evaluated by confocal fluorescence microscopy. These MPCs qualitatively showed significant toxicity and the ability to penetrate into most cell compartments with a strong tendency of finally residing inside membranes. Applications in catalysis, electrocatalysis, and biomedicine are envisaged.
  Journal of the American Chemical Society 12/2011; 134(1). · 9.91 Impact Factor
• Article: Synthesis and characterization of new fluorescent styrene-containing carborane derivatives: the singular quenching role of a phenyl substituent.

  Albert Ferrer-Ugalde, Emilio José Juárez-Pérez, Francesc Teixidor, Clara Viñas, Reijo Sillanpää, Ezequiel Pérez-Inestrosa, Rosario Núñez
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  ABSTRACT: A set of neutral and anionic carborane derivatives in which the styrenyl fragment is introduced as a fluorophore group has been successfully synthesized and characterized. The reaction of the monolithium salts of 1-Ph-1,2-C(2)B(10)H(11), 1-Me-1,2-C(2)B(10)H(11) and 1,2-C(2)B(10)H(12) with one equivalent of 4-vinylbenzyl chloride leads to the formation of compounds 1-3, whereas the reaction of the dilithium salt of 1,2-C(2)B(10)H(12) with two equivalents of 4-vinylbenzyl chloride gives disubstituted compound 4. The closo clusters were degraded using the classical method, KOH in EtOH, to afford the corresponding nido species, which were isolated as tetramethylammonium salts. The crystal structure of the four closo compounds 1-4 were analyzed by X-ray diffraction. All compounds, except 1, display emission properties, with quantum yields dependent on the nature of the cluster (closo or nido) and the substituent on the second C(cluster) atom. In general, closo compounds 2-4 exhibit high fluorescence emission, whereas the presence of a nido cluster produces a decrease of the emission intensity. The presence of a phenyl group bonded to the C(cluster) results in an excellent electron-acceptor unit that produces a quenching of the fluorescence. DFT calculations have confirmed the charge-separation state in 1 to explain the quenching of the fluorescence and the key role of the carboranyl fragment in this luminescent process.
  Chemistry 12/2011; 18(2):544-53. · 5.93 Impact Factor
• Source

  Available from: Clara Viñas

  Article: Design of dinuclear copper species with carboranylcarboxylate ligands: study of their steric and electronic effects.

  Mònica Fontanet, Adrian-Radu Popescu, Xavier Fontrodona, Montserrat Rodríguez, Isabel Romero, Francesc Teixidor, Clara Viñas, Núria Aliaga-Alcalde, Eliseo Ruiz
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  ABSTRACT: A series of new mononuclear and carboranylcarboxylate-bridged dinuclear copper(II) compounds containing the 1-CH(3)-2-CO(2)H-1,2-closo-C(2)B(10)H(10) carborane ligand (LH) has been synthesized. Reaction of different copper salts with LH at room temperature leads to dinuclear compounds of the general formula [Cu(2)(μ-L)(4)(L(t))(2)] (L(t) = thf (1), L(t) = H(2)O (1')). The reaction of 1 and 1' with different terminal pyridyl (py) ligands leads to the formation of a series of structurally analogous complexes by substitution of the terminal ligand thf or H(2)O (L(t) = py (2), p-CF(3)-py (3), p-CH(3)-py (4), pz (6), and 4,4'-bpy (7)), which maintain the structural Cu(2)(μ-O(2)CR)(4) core in the majority of the cases except for o-(CH(3))(2)-py, where a mononuclear compound (5) is exclusively obtained. These compounds have been characterized through analytical, spectroscopic (NMR, IR, UV-visible, ESI-MS) and magnetic techniques. X-ray structural analysis revealed a paddle-wheel structure for the dinuclear compounds, with a square-pyramidal geometry around each copper ion and the carboranylcarboxylate ions bridging two copper atoms in syn-syn mode. The mononuclear complex obtained with the o-(CH(3))(2)-py ligand presents a square-planar structure, in which the carboranylcarboxylate ligand adopts a monodentate coordination mode. The magnetic properties of the dinuclear compounds 1, 3, 4, and 6 show a strong antiferromagnetic coupling in all cases (J = -261 (1), -255 (3), -241 (4), -249 cm(-1) (6)). Computational studies based on hybrid density functional methods have been used to study the magnetic properties of the complexes and also to evaluate their relative stability on the basis of the strength of the bond between each Cu(II) and the terminal ligand.
  Chemistry 11/2011; 17(47):13217-29. · 5.93 Impact Factor
• Article: Stepwise sequential redox potential modulation possible on a single platform.

  Ariadna Pepiol, Francesc Teixidor, Reijo Sillanpää, Marius Lupu, Clara Viñas
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  ABSTRACT: Step by step: The cluster [3,3'-Co(1,2-C(2)B(9)H(11))(2)](-) is an excellent platform for making a stepwise tunable redox potential system by dehydroiodination. With the addition of up to eight iodine substituents (purple; see picture), there is a fall in the E(1/2)(Co(III)/Co(II)) value from -1.80 V to -0.68 V (vs. Fc(+)/Fc; Fc = ferrocene). A practical application of this tunability has been observed in the growth of polypyrrole.
  Angewandte Chemie International Edition 11/2011; 50(52):12491-5. · 13.45 Impact Factor
• Article: Relaxed but highly compact diansa metallacyclophanes.

  Pau Farràs, Francesc Teixidor, Isabel Rojo, Raikko Kivekäs, Reijo Sillanpää, Patricia González-Cardoso, Clara Viñas
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  ABSTRACT: A series of monoansa [μ-1,1'-PR-3,3'-Co(1,2-C(2)B(9)H(10))(2)](-) and diansa [8,8'-μ-(1'',2''-benzene)-μ-1,1'-PR-3,3'-Co(1,2-C(2)B(9)H(9))(2)](-) (R = Ph, (t)Bu) cobaltabisdicarbollidephanes have been synthesized, characterized and studied by NMR, MALDI-TOF-MS, UV-visible spectroscopy, cyclic voltammetry, and DFT calculations. Single crystal X-ray diffraction revealed a highly relaxed structure characterized by the title angle α of 3.8° ([7](-)), this being the smallest angle α for a metallacyclophane. In such compounds, the metal-to-phosphorus distance is less than the sum of their van der Waals radii. The availability of a phosphorus lone pair causes an electron delocalization through the metal, as shown by the abnormal (31)P NMR chemical shift. Remarkably, the combination of a phosphine donor and a phenyl acceptor moieties causes a synergistic effect that is observed through the different techniques used in this study. The importance of having an available lone pair is demonstrated by the oxidation of phosphorus with hydrogen peroxide, sulfur, and elemental black selenium to produce the corresponding P(V) compounds. When the electron lone pair is used to form the bond with the corresponding chalcogen atom, the communication between the donor and acceptor moieties on the diansa metallacyclophane is shut down.
  Journal of the American Chemical Society 09/2011; 133(41):16537-52. · 9.91 Impact Factor
• Article: Binaphthyl platform as starting materials for the preparation of electron rich benzo[g,h,i]perylenes. Application to molecular architectures based on amino benzo[g,h,i]perylenes and carborane combinations.

  Grégory Pieters, Anne Gaucher, Damien Prim, Thierry Besson, José Giner Planas, Francesc Teixidor, Clara Viñas, Mark E Light, Michael B Hursthouse
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  ABSTRACT: Valuable amino benzo[g,h,i]perylenes have been obtained through a one pot electrophilic aromatic substitution--Scholl reaction sequence. Novel molecular architectures combining 3D-o-carborane and planar amino benzo[g,h,i]perylene units are described. Photophysical properties of amino benzo[g,h,i]perylene and the carborane-appended derivatives are discussed.
  Chemical Communications 07/2011; 47(27):7725-7. · 6.17 Impact Factor
• Article: Synthesis and fluorescence emission of neutral and anionic di- and tetra-carboranyl compounds.

  Frédéric Lerouge, Albert Ferrer-Ugalde, Clara Viñas, Francesc Teixidor, Reijo Sillanpää, Arturo Abreu, Elba Xochitiotzi, Norberto Farfán, Rosa Santillan, Rosario Núñez
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  ABSTRACT: A new family of photoluminescent neutral and anionic di-carboranyl and tetra-carboranyl derivatives have been synthesized and characterized. The reaction of α,α'-bis(3,5-bis(bromomethyl)phenoxy-m-xylene with 4 equiv. of the monolithium salt of 1-Ph-1,2-C(2)B(10)H(11) or 1-Me-1,2-C(2)B(10)H(11) gives the neutral tetracarboranyl-functionalized aryl ether derivatives closo-1 and closo-2, respectively. The addition of the monolithium salt of 1-Ph-1,2-closo-C(2)B(10)H(11) to α,α,'-dibromo-m-xylene or 2,6-dibromomethyl-pyridine gives the corresponding di-carboranyl derivatives closo-3 and closo-4. These compounds, which contain four or two closo clusters, were degraded using the classical method, KOH in EtOH, affording the corresponding nido species, which were isolated as potassium or tetramethylammonium salts. All the compounds were characterized by IR, (1)H, (11)B and (13)C NMR spectroscopy, and the crystal structure of closo-3 was analysed by X-ray diffraction. The carboranyl fragments are bonded through CH(2) units to different organic moieties, and their influence on the photoluminescent properties of the final molecules has been studied. All the closo- and nido-carborane derivatives exhibit a blue emission under ultraviolet excitation at room temperature in different solvents. The fluorescence properties of these closo and nido-derivatives depend on the substituent (Ph or Me) bonded to the C(cluster), the solvent polarity, and the organic unit bearing the carborane clusters (benzene or pyridine). In the case of nido-derivatives, an important effect of the cation is also observed.
  Dalton Transactions 06/2011; 40(29):7541-50. · 3.84 Impact Factor
• Article: A highly radiopaque vertebroplasty cement using tetraiodinated o-carborane additive.

  Ariadna Pepiol, Francesc Teixidor, Ketie Saralidze, Cees van der Marel, Paul Willems, Laura Voss, Menno L W Knetsch, Clara Vinas, Leo H Koole
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  ABSTRACT: Bone cements for vertebroplasty must have a much better radiocontrast level than cements for knee or hip arthroplasty. This is generally accomplished by adding a relatively large portion of BaSO(4), although this affects the physical-mechanical and biological properties of the cement. This prompted us to develop an alternative radiopaque cement, on the basis of unique highly radiopaque methacrylic microspheres. These contain iodine in two modalities: (i) covalently linked to the methacrylic polymer, and (ii) as constituent of the stable tetraiodocarborane 8,9,10,12-I(4)-1,2-closo-C(2)B(10)H(8). The total iodine content in these particles exceeded 30% by mass. These radiopaque microspheres as well as the cement made thereof were characterized extensively, e.g., by scanning electron microscopy, X-ray contrast measurements, X-ray photoelectron spectroscopy, measurements of compressive strength, infrared spectroscopy, and solid state (11)B{(1)H} NMR spectroscopy. Furthermore, the new cement was subjected to several biocompatibility tests in vitro. The results show that the new bone cement fulfills all physico-chemical criteria for use in vertebroplasty. Further data on the cement's biocompatibility (in vitro), as well as on the handling parameters and doughviscosity, indicate that this material has a potential to become an alternative to vertebroplasty cements with a high BaSO(4) content. The new cement provides two significant advantages: (i) controlled viscosity in the dough phase, which facilitates precise injection during the vertebroplasty procedure; (ii) excellent structural stability, which precludes leaching of contrast post-implantation.
  Biomaterials 06/2011; 32(27):6389-98. · 7.40 Impact Factor
• Article: A theta-shaped amphiphilic cobaltabisdicarbollide anion: transition from monolayer vesicles to micelles.

  Pierre Bauduin, Sylvain Prevost, Pau Farràs, Francesc Teixidor, Olivier Diat, Thomas Zemb
  Angewandte Chemie International Edition 05/2011; 50(23):5298-300. · 13.45 Impact Factor
• Article: A Theta-Shaped Amphiphilic Cobaltabisdicarbollide Anion: A New Transition From Monolayer Vesicles to Micelles.

  Pierre Bauduin, Sylvain Prevost, Pau Farràs, Francesc Teixidor, Olivier Diat, Thomas Zemb
  Angewandte Chemie International Edition 05/2011; · 13.45 Impact Factor
• Article: Unprecedented B–H Activation Through Pd-Catalysed B–C vinyl Bond Coupling on Borane Systems

  Pau, Clara viñas, Francesc Teixidor
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  ABSTRACT: Farràs, [a] David Olid-Britos, [a][] Clara Viñas, [a] and Francesc Teixidor* [a] Keywords: Cobalt / Palladium / Heck reaction / Cross-coupling / B–C coupling A Pd-induced cascade B–C vinyl coupling that produces mul-tiple B–C vinyl bonds starting from a single B–I bond has been demonstrated. The process is most probably stimulated by the geometrical disposition of the B–H bonds confronting the B–Pd sites, along with the hydride character of the B–H units.
  European Journal of Inorganic Chemistry 04/2011; · 3.05 Impact Factor