151
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Poduval MK, Burrezo PM, Casado J, López Navarrete JT, Ortiz RP, Kim TH. Novel Thiophene–Phenylene–Thiophene Fused Bislactam-Based Donor–Acceptor Type Conjugate Polymers: Synthesis by Direct Arylation and Properties. Macromolecules 2013. [DOI: 10.1021/ma4018907] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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152
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González-Cano RC, Saini G, Jacob J, López Navarrete JT, Casado J, Ruiz Delgado MC. Interplay of α,α- versus α,β-Conjugation in the Excited States and Charged Defects of Branched Oligothiophenes as Models for Dendrimeric Materials. Chemistry 2013; 19:17165-71. [DOI: 10.1002/chem.201302244] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Revised: 09/12/2013] [Indexed: 11/10/2022]
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153
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Janeliunas D, Eelkema R, Nieto-Ortega B, Ramírez Aguilar FJ, López Navarrete JT, van der Mee L, Stuart MCA, Casado J, van Esch JH. Designing new symmetrical facial oligothiophene amphiphiles. Org Biomol Chem 2013; 11:8435-42. [PMID: 24196136 DOI: 10.1039/c3ob41645c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this study we designed a new class of symmetrical facial oligothiophene amphiphiles, which could be obtained in fewer steps than for previously reported analogues, but still possess the specific substituent sequence to control their backbone curvature. This novel design allows the late-stage introduction of hydrophilic groups, aiding both purification and ease of structure variation. Following the new synthetic scheme, symmetrical ter- and sexi-thiophenes were synthesized, analysed and their properties were compared to their non-symmetrical analogues. Surprisingly, the self-assembly behaviour in water, aggregate morphologies and photo-physical properties turned out to be significantly different despite the same ratio of hydrophilic and hydrophobic substituents. The new substitution pattern resulted in a drastic decrease of the critical aggregation concentration and an increase of the aggregate size. The symmetrical positioning of the substituents also heavily influenced the photo-physical properties. The changes were observed as large blue shifts in the absorption and emission spectra in water when compared to similar regio-regular oligothiophene amphiphiles.
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154
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Ponce Ortiz R, Herrera H, Mancheño MJ, Seoane C, Segura JL, Mayorga Burrezo P, Casado J, López Navarrete JT, Facchetti A, Marks TJ. Molecular and Electronic-Structure Basis of the Ambipolar Behavior of Naphthalimide-Terthiophene Derivatives: Implementation in Organic Field-Effect Transistors. Chemistry 2013; 19:12458-67. [DOI: 10.1002/chem.201301489] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Indexed: 11/09/2022]
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155
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Zeng Z, Lee S, Zafra JL, Ishida M, Zhu X, Sun Z, Ni Y, Webster RD, Li RW, López Navarrete JT, Chi C, Ding J, Casado J, Kim D, Wu J. Tetracyanoquaterrylene and Tetracyanohexarylenequinodimethanes with Tunable Ground States and Strong Near-Infrared Absorption. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201305348] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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156
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Zeng Z, Lee S, Zafra JL, Ishida M, Zhu X, Sun Z, Ni Y, Webster RD, Li RW, López Navarrete JT, Chi C, Ding J, Casado J, Kim D, Wu J. Tetracyanoquaterrylene and Tetracyanohexarylenequinodimethanes with Tunable Ground States and Strong Near-Infrared Absorption. Angew Chem Int Ed Engl 2013; 52:8561-5. [DOI: 10.1002/anie.201305348] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Indexed: 11/06/2022]
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157
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Casado J, Rodríguez I, Carpinteiro I, Ramil M, Cela R. Gas chromatography quadrupole time-of-flight mass spectrometry determination of benzotriazole ultraviolet stabilizers in sludge samples. J Chromatogr A 2013; 1293:126-32. [DOI: 10.1016/j.chroma.2013.03.050] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Revised: 03/14/2013] [Accepted: 03/15/2013] [Indexed: 10/27/2022]
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158
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Casado J, Rodríguez I, Ramil M, Cela R. Polyethersulfone solid-phase microextraction followed by liquid chromatography quadrupole time-of-flight mass spectrometry for benzotriazoles determination in water samples. J Chromatogr A 2013; 1299:40-7. [PMID: 23777835 DOI: 10.1016/j.chroma.2013.05.061] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Revised: 05/23/2013] [Accepted: 05/27/2013] [Indexed: 01/26/2023]
Abstract
A microextraction method for the determination of 1H-benzotriazole (BTri), and four polar derivatives (4 and 5-methyl-1H-benzotriazole, 4-TTri and 5-TTri; 5,6-dimethyl-1H-benzotriazole, XTri; and 5-chloro-1H-benzotriazole, 5-ClBTri), in surface and wastewater samples is presented. Analytes were pre-concentrated using a disposable, low cost polyethersulfone (PES) sorbent and further analysed by liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). Parameters affecting the efficiency of sample preparation (extraction conditions and desorption solvent) and those controlling the performance of LC-MS determination were investigated. Analytes were extracted from 15mL water samples, containing a 30% (w/v) of sodium chloride (4.5g) and adjusted at pH 4.5, using a tubular PES sorbent (5cm length×0.7mm o.d., sorbent volume 42μL). After methanol desorption and solvent exchange, benzotriazoles were determined by LC-MS, with chromatograms extracted using a mass window of 20ppm, centred in their [M+H](+) ions. The identity of chromatographic peaks was confirmed with accurate ion product scan (MS/MS) spectra. The method provided limits of quantification (LOQs) between 0.005 and 0.100μgL(-1), and relative recoveries from 81% to 124% (except for XTri in sewage samples, ca. 60%) with associated standard deviations between 2% and 9%. When compared with polydimethylsiloxane covered stir-bars (coating volume 24μL), the PES polymer achieved significant higher responses (5-20-fold) for these polar pollutants. BTri and tolyltriazoles (4-TTri and 5-TTri) were found in urban sewage and river water samples, affected by wastewater discharges, with the maximum concentration (5.9μgL(-1)) corresponding to BTri in raw wastewater.
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159
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Zeng Z, Ishida M, Zafra JL, Zhu X, Sung YM, Bao N, Webster RD, Lee BS, Li RW, Zeng W, Li Y, Chi C, López Navarrete JT, Ding J, Casado J, Kim D, Wu J. Pushing extended p-quinodimethanes to the limit: stable tetracyano-oligo(N-annulated perylene)quinodimethanes with tunable ground states. J Am Chem Soc 2013; 135:6363-71. [PMID: 23560651 DOI: 10.1021/ja402467y] [Citation(s) in RCA: 132] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
p-Quinodimethane (p-QDM) is a fundamental building block for the design of π-conjugated systems with low band gap and open-shell biradical character. However, synthesis of extended p-QDMs has usually suffered from their intrinsic high reactivity and poor solubility. In this work, benzannulation together with terminal cyano-substitution was demonstrated to be an efficient approach for the synthesis of a series of soluble and stable tetracyano-oligo(N-annulated perylene)quinodimethanes nPer-CN (n = 1-6), with the longest molecule having 12 para-linked benzenoid rings! The geometry and electronic structures of these oligomers were investigated by steady-state and transient absorption spectroscopy, nuclear magnetic resonance, electron spin resonance, superconducting quantum interference device, and FT Raman spectroscopy assisted by density functional theory calculations. They showed tunable ground states, varying from a closed-shell quinoidal structure for monomer, to a singlet biradical for dimer, trimer, and tetramer, and to a triplet biradical for pentamer and hexamer. Large two-photon absorption cross-section values were observed in the near-infrared range, which also exhibited a clear chain-length dependence.
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160
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Casado J, Burrezo PM, Ramírez FJ, Navarrete JTL, Lapidus SH, Stephens PW, Vo HL, Miller JS, Mota F, Novoa JJ. Evidence for Multicenter Bonding in Dianionic Tetracyanoethylene Dimers by Raman Spectroscopy. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201207813] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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161
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Casado J, Burrezo PM, Ramírez FJ, Navarrete JTL, Lapidus SH, Stephens PW, Vo HL, Miller JS, Mota F, Novoa JJ. Evidence for Multicenter Bonding in Dianionic Tetracyanoethylene Dimers by Raman Spectroscopy. Angew Chem Int Ed Engl 2013; 52:6421-5. [DOI: 10.1002/anie.201207813] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Revised: 03/04/2013] [Indexed: 11/10/2022]
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162
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Marco AB, Andreu R, Franco S, Garín J, Orduna J, Villacampa B, Diosdado BE, López Navarrete JT, Casado J. Push–pull systems bearing a quinoid/aromatic thieno[3,2-b]thiophene moiety: synthesis, ground state polarization and second-order nonlinear properties. Org Biomol Chem 2013; 11:6338-49. [DOI: 10.1039/c3ob41278d] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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163
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Costa RD, Aragó J, Ortí E, Pappenfus TM, Mann KR, Matczyszyn K, Samoc M, Zafra JL, López Navarrete JT, Casado J. Impact of the synergistic collaboration of oligothiophene bridges and ruthenium complexes on the optical properties of dumbbell-shaped compounds. Chemistry 2012. [PMID: 23208872 DOI: 10.1002/chem.201202456] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The linear and non-linear optical properties of a family of dumbbell-shaped dinuclear complexes, in which an oligothiophene chain with various numbers of rings (1, 3, and 6) acts as a bridge between two homoleptic tris(2,2'-bipyridine)ruthenium(II) complexes, have been fully investigated by using a range of spectroscopic techniques (absorption and luminescence, transient absorption, Raman, and non-linear absorption), together with density functional theory calculations. Our results shed light on the impact of the synergistic collaboration between the electronic structures of the two chemical moieties on the optical properties of these materials. Experiments on the linear optical properties of these compounds indicated that the length of the oligothiophene bridge was critical for luminescent behavior. Indeed, no emission was detected for compounds with long oligothiophene bridges (compounds 3 and 4, with 3 and 6 thiophene rings, respectively), owing to the presence of the (3)π-π* state of the conjugated bridge below the (3)MLCT-emitting states of the end-capping Ru(II) complexes. In contrast, the compound with the shortest bridge (2, one thiophene ring) shows excellent photophysical features. Non-linear optical experiments showed that the investigated compounds were strong non-linear absorbers in wide energy ranges. Indeed, their non-linear absorption was augmented upon increasing the length of the oligothiophene bridge. In particular, the compound with the longest oligothiophene bridge not only showed strong two-photon absorption (TPA) but also noteworthy three-photon-absorption behavior, with a cross-section value of 4×10(-78) cm(6) s(2) at 1450 nm. This characteristic was complemented by the strong excited-state absorption (ESA) that was observed for compounds 3 and 4. As a matter of fact, the overlap between the non-linear absorption and ESA establishes compounds 3 and 4 as good candidates for optical-power-limiting applications.
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164
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Zhu X, Tsuji H, Navarrete JTL, Casado J, Nakamura E. Carbon-bridged oligo(phenylenevinylene)s: stable π-systems with high responsiveness to doping and excitation. J Am Chem Soc 2012; 134:19254-9. [PMID: 23106224 DOI: 10.1021/ja309318s] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The high responsiveness of π-conjugated materials to external stimuli, such as electrons and photons, accounts for both their utility in optoelectronic applications and their chemical instability. Extensive studies on heteroatom-stabilized π-conjugated systems notwithstanding, it is still difficult to combine high performance and stability. We report here that carbon-bridged oligo(p-phenylenevinylene)s (COPV-n) are not only more responsive to doping and photoexcitation but also more stable than the conventional p-phenylenevinylenes and poly(3-hexylthiophene), surviving photolysis very well in air, suggesting that they could serve as building blocks for optoelectronic applications. Activation of the ground state by installation of bond angle strain toward the doped or photoexcited state and the flat, rigid, and hindered structure endows COPVs with stimuli-responsiveness and stability without recourse to heteroatoms. For example, COPV-6 can be doped with an extremely small reorganization energy and form a bipolaron delocalized over the entire π-conjugated system. Applications to bulk and molecular optoelectronic devices are foreseen.
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165
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Li Y, Heng WK, Lee BS, Aratani N, Zafra JL, Bao N, Lee R, Sung YM, Sun Z, Huang KW, Webster RD, López Navarrete JT, Kim D, Osuka A, Casado J, Ding J, Wu J. Kinetically Blocked Stable Heptazethrene and Octazethrene: Closed-Shell or Open-Shell in the Ground State? J Am Chem Soc 2012; 134:14913-22. [DOI: 10.1021/ja304618v] [Citation(s) in RCA: 216] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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166
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González Cano RC, Herrera H, Segura JL, López Navarrete JT, Ruiz Delgado MC, Casado J. Conformational Control of the Electronic Properties of an α-β Terthiophene: Lessons from a Precursor Towards Dendritic Hyperbranched Oligo- and Poly-Thiophenes. Chemphyschem 2012; 13:3893-900. [DOI: 10.1002/cphc.201200620] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Indexed: 11/10/2022]
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167
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Zeng Z, Sung YM, Bao N, Tan D, Lee R, Zafra JL, Lee BS, Ishida M, Ding J, López Navarrete JT, Li Y, Zeng W, Kim D, Huang KW, Webster RD, Casado J, Wu J. Stable Tetrabenzo-Chichibabin’s Hydrocarbons: Tunable Ground State and Unusual Transition between Their Closed-Shell and Open-Shell Resonance Forms. J Am Chem Soc 2012; 134:14513-25. [DOI: 10.1021/ja3050579] [Citation(s) in RCA: 179] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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168
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Nieto-Ortega B, Nebot VJ, Miravet JF, Escuder B, Navarrete JTL, Casado J, Ramírez FJ. Vibrational Circular Dichroism Shows Reversible Helical Handedness Switching in Peptidomimetic l-Valine Fibrils. J Phys Chem Lett 2012; 3:2120-2124. [PMID: 26295757 DOI: 10.1021/jz300725d] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We elucidate the supramolecular organization in the form of microsize fibrils of gels formed by a l-Valine peptidomimetic compound. Analysis was based on circular dichroism spectroscopies, vibrational (VCD) and electronic (CD), supported by microscopy (atomic force and scanning electron). We show how the VCD spectra give account of the micrometric structure of the fibrils formed by the helicoidal arrangement of simpler proto-fibrils, which are organized in a lower hierarchical level. This ability is used to monitorize a fully reversible change in the handedness of the helix by modulating different external stimuli as pH or ionic strength, thus providing the first observation by VCD of such a phenomenon in a short peptide.
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169
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Bouhifd M, Bories G, Casado J, Coecke S, Norlén H, Parissis N, Rodrigues RM, Whelan MP. Automation of an in vitro cytotoxicity assay used to estimate starting doses in acute oral systemic toxicity tests. Food Chem Toxicol 2012; 50:2084-96. [PMID: 22465836 DOI: 10.1016/j.fct.2012.03.046] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Revised: 02/23/2012] [Accepted: 03/09/2012] [Indexed: 11/27/2022]
Abstract
Application of High Throughput Screening (HTS) to the regulatory safety assessment of chemicals is still in its infancy but shows great promise in terms of facilitating better understanding of toxicological modes-of-action, reducing the reliance on animal testing, and allowing more data-poor chemicals to be assessed at a reasonable cost. To promote the uptake and acceptance of HTS approaches, we describe in a stepwise manner how a well known cytotoxicity assay can be automated to increase throughput while maintaining reliability. Results generated with selected reference chemicals compared very favourably with data obtained from a previous international validation study concerning the prediction of acute systemic toxicity in rodents. The automated assay was then included in a formal ECVAM validation study to determine if the assay could be used for binary classification of chemicals with respect to their acute oral toxicity, using a threshold equivalent to a dose of 2000 mg/kg b.w. in a rodent bioassay (LD50). This involved the blind-testing of 56 reference chemicals on the HTS platform to produce concentration-response and IC50 data. Finally, the assay was adapted to a format more suited to higher throughput testing without compromising the quality of the data obtained.
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170
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Rodríguez González S, Ruiz Delgado MC, Caballero R, De la Cruz P, Langa F, López Navarrete JT, Casado J. Delocalization-to-Localization Charge Transition in Diferrocenyl-Oligothienylene-Vinylene Molecular Wires as a Function of the Size by Raman Spectroscopy. J Am Chem Soc 2012; 134:5675-81. [DOI: 10.1021/ja3005607] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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171
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Hennrich G, Nieto-Ortega B, Gómez-Lor B, Gutierrez E, de Vega L, Cavero E, Ramírez FJ, López Navarrete JT, Casado J. Controlling the Macroscopic Chirality of Organic Materials Based on 1,3,5-Trialkynylbenzenes. European J Org Chem 2012. [DOI: 10.1002/ejoc.201101636] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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172
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Kuehnel MF, Schlöder T, Riedel S, Nieto-Ortega B, Ramírez FJ, López Navarrete JT, Casado J, Lentz D. Synthesis of the Smallest Axially Chiral Molecule by Asymmetric Carbon-Fluorine Bond Activation. Angew Chem Int Ed Engl 2012; 51:2218-20. [DOI: 10.1002/anie.201108105] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2011] [Indexed: 11/07/2022]
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173
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Kuehnel MF, Schlöder T, Riedel S, Nieto-Ortega B, Ramírez FJ, López Navarrete JT, Casado J, Lentz D. Synthese des kleinsten axial-chiralen Moleküls durch asymmetrische Kohlenstoff-Fluor-Bindungsaktivierung. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201108105] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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174
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Casado J, Ponce Ortiz R, López Navarrete JT. Quinoidal oligothiophenes: new properties behind an unconventional electronic structure. Chem Soc Rev 2012; 41:5672-86. [DOI: 10.1039/c2cs35079c] [Citation(s) in RCA: 207] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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175
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Nieto-Ortega B, Ramírez FJ, Amabilino DB, Linares M, Beljonne D, Navarrete JTL, Casado J. Electronic and vibrational circular dichroism spectroscopies for the understanding of chiral organization in porphyrin aggregates. Chem Commun (Camb) 2012; 48:9147-9. [DOI: 10.1039/c2cc34374f] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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