15 research outputs found

    Synthesis, properties, and some rhodium, iridium, and platinum complexes of a series of bulky m-terphenylphosphine ligands

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    A series of sterically demanding aryl phosphine ligands (L) bearing terphenyl substituents, PR2Ar′ (R = hydrocarbyl, Ar′ = 2,6-diarylphenyl radical) has been prepared and characterized. The stability of these ligands towards oxidation in the air has been tested, and theoretical and experimental studies aimed to provide information on their electronic and steric properties have been performed. Treatment of the metal dimers [MCl(COD)]2(M = Rh, Ir; COD = 1,5-cyclooctadiene) with ligands PMe2ArXyl2(L1) and PMe2ArDipp2(L5), in a 1:1 metal:ligand ratio, afforded the expected square-planar 16-electron complexes [MCl(COD)(PMe2ArXyl2)] and [MCl(COD)(PMe2ArDipp2)], respectively. These compounds were readily converted into the corresponding dicarbonyl derivatives, [MCl(CO)2(PMe2ArXyl2)] and [MCl(CO)2(PMe2ArDipp2)], respectively. While the expected κ1-P coordination mode of the PR2Ar′ ligands is found for these rhodium and iridium species, the mononuclear Pt(II) derivative obtained by reaction of PtCl2with PMe2ArDipp2has composition [PtCl2(PMe2ArDipp2)], and exhibits a bidentate κ1-P, η1-arene coordination mode involving one of the ipso carbon atoms of a flanking terphenyl aryl ring. The corresponding carbonyl compound [PtCl2(CO)(PMe2ArDipp2)], was generated under a CO atmosphere and exhibits κ1-P coordination mode.Ministerio de Ciencia CTQ2013-42501-P, CTQ2014-51912-REDC, CTQ-2014-52769-C3-3-RJunta de Andalucía FQM-119 P09-FQM-4832, FQM-2126European Union 26722

    Oncology providers' perspectives on endocrine therapy prescribing and management.

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    Adjuvant endocrine therapy (ET) can reduce the risk of recurrence among females with hormone receptor-positive breast cancer. Overall, initiation and adherence to ET are suboptimal, though reasons are not well described. The study's objective was to better understand ET decision making, prescribing, and patient management from oncology providers' perspectives. Using purposive sampling, we recruited oncology providers who saw five or more breast cancer patients per week (n=20). We conducted 30-45-minute telephone interviews, using a semistructured guide to elicit perspectives on ET use. We used thematic content analysis to systematically identify categories of meaning and double-coded transcripts using Atlas.ti. Providers recommend ET to all eligible patients except those with contraindications or other risk factors. Providers base their ET prescribing decisions on the patient's menopausal status, side effects, and comorbidities. ET is typically discussed multiple times: at the onset of breast cancer treatment and in more detail after other treatment completion. Providers felt that the associated recurrence risk reduction is the most compelling argument for patients during ET decision making. While providers rarely perceived noninitiation as a problem, nonadherence was prevalent, often due to unresolvable side effects. From the clinicians' perspectives, side effects from ET are the dominant factor in nonadherence. Efforts to improve adherence should focus on strategies to minimize side effects and ensure clinicians and patients are well informed regarding optimal side effect management. This finding has important implications for novel endocrine regimens that offer improved outcomes through longer duration or more intensive therapy

    BHPR research: qualitative1. Complex reasoning determines patients' perception of outcome following foot surgery in rheumatoid arhtritis

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    Background: Foot surgery is common in patients with RA but research into surgical outcomes is limited and conceptually flawed as current outcome measures lack face validity: to date no one has asked patients what is important to them. This study aimed to determine which factors are important to patients when evaluating the success of foot surgery in RA Methods: Semi structured interviews of RA patients who had undergone foot surgery were conducted and transcribed verbatim. Thematic analysis of interviews was conducted to explore issues that were important to patients. Results: 11 RA patients (9 ♂, mean age 59, dis dur = 22yrs, mean of 3 yrs post op) with mixed experiences of foot surgery were interviewed. Patients interpreted outcome in respect to a multitude of factors, frequently positive change in one aspect contrasted with negative opinions about another. Overall, four major themes emerged. Function: Functional ability & participation in valued activities were very important to patients. Walking ability was a key concern but patients interpreted levels of activity in light of other aspects of their disease, reflecting on change in functional ability more than overall level. Positive feelings of improved mobility were often moderated by negative self perception ("I mean, I still walk like a waddling duck”). Appearance: Appearance was important to almost all patients but perhaps the most complex theme of all. Physical appearance, foot shape, and footwear were closely interlinked, yet patients saw these as distinct separate concepts. Patients need to legitimize these feelings was clear and they frequently entered into a defensive repertoire ("it's not cosmetic surgery; it's something that's more important than that, you know?”). Clinician opinion: Surgeons' post operative evaluation of the procedure was very influential. The impact of this appraisal continued to affect patients' lasting impression irrespective of how the outcome compared to their initial goals ("when he'd done it ... he said that hasn't worked as good as he'd wanted to ... but the pain has gone”). Pain: Whilst pain was important to almost all patients, it appeared to be less important than the other themes. Pain was predominately raised when it influenced other themes, such as function; many still felt the need to legitimize their foot pain in order for health professionals to take it seriously ("in the end I went to my GP because it had happened a few times and I went to an orthopaedic surgeon who was quite dismissive of it, it was like what are you complaining about”). Conclusions: Patients interpret the outcome of foot surgery using a multitude of interrelated factors, particularly functional ability, appearance and surgeons' appraisal of the procedure. While pain was often noted, this appeared less important than other factors in the overall outcome of the surgery. Future research into foot surgery should incorporate the complexity of how patients determine their outcome Disclosure statement: All authors have declared no conflicts of interes

    Unveiling the latent reactivity of the Cp* ligand (C5Me5-) towards carbon nucleophiles on an iridium complex. Supporting Information

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    The divergent reactivity of the cationic iridium complex [(η5-C5Me5)IrCl(PMe2ArDipp2)]+ (ArDipp2 = C6H3–2,6-(C6H3–2,6-iPr2)2) toward organolithium and Grignard reagents is described. The noninnocent behavior of the Cp* ligand, a robust spectator in the majority of stoichiometric and catalytic reactions, was manifested by its unforeseen electrophilic character toward organolithium reagents LiMe, LiEt, and LinBu. In these unconventional transformations, the metal center is only indirectly involved by means of the Ir(III)/Ir(I) redox cycle. In the presence of less nucleophilic organolithium reagents, the Cp* ligand also exhibits noninnocent behavior undergoing facile deprotonation, which is also concomitant with the reduction of the metal center. In turn, the weaker alkylating agents EtMgBr and MeMgBr effectively achieve the alkylation of the metal center. These reactive iridium(III) alkyls partake in subsequent reactions: while the ethyl complex undergoes β-H elimination, the methyl derivative releases methane by a remote C–H bond activation. Computational studies, including the quantum theory of atoms in molecules (QTAIM), support that the preferential activation of the non-benzylic C–H bonds takes place via sigma-bond metathesis.Peer reviewe

    Unveiling the Latent Reactivity of Cp* Ligands (C5Me5-) toward Carbon Nucleophiles on an Iridium Complex

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    The divergent reactivity of the cationic iridium complex [(η5-C5Me5)IrCl(PMe2ArDipp2)]+ (ArDipp2 = C6H3-2,6-(C6H3-2,6-iPr2)2) toward organolithium and Grignard reagents is described. The noninnocent behavior of the Cp* ligand, a robust spectator in the majority of stoichiometric and catalytic reactions, was manifested by its unforeseen electrophilic character toward organolithium reagents LiMe, LiEt, and LinBu. In these unconventional transformations, the metal center is only indirectly involved by means of the Ir(III)/Ir(I) redox cycle. In the presence of less nucleophilic organolithium reagents, the Cp* ligand also exhibits noninnocent behavior undergoing facile deprotonation, which is also concomitant with the reduction of the metal center. In turn, the weaker alkylating agents EtMgBr and MeMgBr effectively achieve the alkylation of the metal center. These reactive iridium(III) alkyls partake in subsequent reactions: while the ethyl complex undergoes β-H elimination, the methyl derivative releases methane by a remote C-H bond activation. Computational studies, including the quantum theory of atoms in molecules (QTAIM), support that the preferential activation of the non-benzylic C-H bonds takes place via sigma-bond metathesis.This work has been supported by the European Research Council (ERC Starting Grant, CoopCat, 756575). We also thank Grant PID2019-110856GA-I00 funded by MCIN/AEI/ 10.13039/501100011033, Junta de Andalucía (P18-FR-4688) and US/JUNTA/FEDER, UE (US-1380849). J.J.M. thanks Junta de Andalucía for the postdoctoral program “Personal Investigador Doctor” (ref. DOC_00153). The authors gratefully acknowledge the financial support provided by the Consejo Superior de Investigaciones Científicas (studentship JAEINT_21_00695 granted to A.P.-M.) and the use of CESGA computational facilities.Peer reviewe

    Isomerization of a cationic (η<sup>5</sup>-C<sub>5</sub>Me<sub>5</sub>)Ir(III) complex involving remote C–C and C–H bond formation

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    The reactivity of an unsaturated, cationic (C5Me5)Ir(III) complex (2(Xyl)þ) bearing the xylyl-substituted terphenyl phosphine PMe2ArXyl2 (ArXyl2 = C6H3-2,6-(C6H3-2,6-Me2)2) towards triethylamine (NEt3) is studied and compared to our previous investigations based on the related complex 2(Dipp)þ containing the bulkier phosphine PMe2ArDipp2 (ArDipp2 = C6H3-2,6-(C6H3-2,6-iPr2)2). Low-temperature multinuclear NMR studies support the formation of a C–C bond between the deprotonated C5Me5 ligand and a flanking xylyl ring of the phosphine, which becomes dearomatized (complex 4(Xyl)þ). Interestingly, this complex presents divergent reactivity relative to the bulkier diisopropylphenyl counterpart, undergoing formal addition of HCl to yield complex 5 (Xyl)þ, isomeric to the starting complex 2(Xyl)þ. These transformations are rationalized by means of Density Functional Theory (DFT) calculationsPeer reviewe

    Isomerization of a cationic (η<sup>5</sup>-C<sub>5</sub>Me<sub>5</sub>)Ir(III) complex involving remote C–C and C–H bond formation

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    The reactivity of an unsaturated, cationic (C5Me5)Ir(III) complex (2(Xyl)+) bearing the xylyl-substituted terphenyl phosphine PMe2ArXyl2 (ArXyl2 = C6H3-2,6-(C6H3-2,6-Me2)2) towards triethylamine (NEt3) is studied and compared to our previous investigations based on the related complex 2(Dipp)+ containing the bulkier phosphine PMe2ArDipp2 (ArDipp2 = C6H3-2,6-(C6H3-2,6-iPr2)2). Low-temperature multinuclear NMR studies support the formation of a C–C bond between the deprotonated C5Me5 ligand and a flanking xylyl ring of the phosphine, which becomes dearomatized (complex 4(Xyl)+). Interestingly, this complex presents divergent reactivity relative to the bulkier diisopropylphenyl counterpart, undergoing formal addition of HCl to yield complex 5(Xyl)+, isomeric to the starting complex 2(Xyl)+. These transformations are rationalized by means of Density Functional Theory (DFT) calculations.</p

    Cationic (η5-C5Me4R)RhIII Complexes with Metalated Aryl Phosphines Featuring η4-Phosphorus plus Pseudo-Allylic Coordination

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    In this contribution we study experimentally and computationally some electrophilic cationic (η-CMeR)Rh complexes containing a cyclometalated bis(aryl) phosphine, PR′Ar. The phosphine Ar groups feature methyl substituents at the 2- and 6-positions of the aromatic rings, allowing the formation of the complexes [(η-CMeR)Rh(CP)] (3), where the metalated phosphine exhibits η coordination to rhodium through phosphorus and the carbon atoms of the adjoining pseudo-allylic functionality. The solution and solid-state structures of complexes 3 have been studied by NMR and X-ray methods and their electronic properties investigated with the aid of DFT calculations. The Lewis acid behavior of complexes 3 has also been addressed, concentrating on reactivity toward CO, H,and hydrosilanes. Some catalytic Si-H/Si-D exchange and hydrosilylation reactions are also reported.Peer Reviewe

    Cationic (η<sup>5</sup>‑C<sub>5</sub>Me<sub>4</sub>R)Rh<sup>III</sup> Complexes with Metalated Aryl Phosphines Featuring η<sup>4</sup>‑Phosphorus plus Pseudo-Allylic Coordination

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    In this contribution we study experimentally and computationally some electrophilic cationic (η<sup>5</sup>-C<sub>5</sub>Me<sub>4</sub>R)­Rh<sup>III</sup> complexes containing a cyclometalated bis­(aryl) phosphine, PR′Ar<sub>2</sub>. The phosphine Ar groups feature methyl substituents at the 2- and 6-positions of the aromatic rings, allowing the formation of the complexes [(η<sup>5</sup>-C<sub>5</sub>Me<sub>4</sub>R)­Rh­(C<sup>∧</sup>P)]<sup>+</sup> (<b>3</b><sup><b>+</b></sup>), where the metalated phosphine exhibits η<sup>4</sup> coordination to rhodium through phosphorus and the carbon atoms of the adjoining pseudo-allylic functionality. The solution and solid-state structures of complexes <b>3</b><sup><b>+</b></sup> have been studied by NMR and X-ray methods and their electronic properties investigated with the aid of DFT calculations. The Lewis acid behavior of complexes <b>3</b><sup><b>+</b></sup> has also been addressed, concentrating on reactivity toward CO, H<sub>2</sub> ,and hydrosilanes. Some catalytic Si–H/Si–D exchange and hydrosilylation reactions are also reported

    Manual práctico para la elaboración del Trabajo Fin de Grado (Grados en Educación)

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    La elaboración y defensa del Trabajo Fin de Grado (TFG) representa el último paso y requisito para la obtención del título universitario cursado. Supone la ocasión de reflejar en un documento escrito los aprendizajes alcanzados y las competencias desarrolladas a lo largo de los cuatro cursos que han precedido su elaboración. Este trabajo, que constituye un reto a nivel académico, puede representar también, a nivel personal, una tarea repleta de dudas, miedos y tensiones. Por este motivo se presenta este manual con el objeto de que el alumnado de Grado cuente con un documento que le oriente y guíe en este proceso. Por tanto, el objetivo es allanar el camino conducente a la obtención del título, facilitando la elaboración del Trabajo Fin de Grado y exponiendo cuestiones clave para su desarrollo. Este documento sigue lo establecido en la normativa aprobada para la realización del TFG por la Universidad de Extremadura y por el Centro en el que este TFG debe desarrollarse y presentarse, la Facultad de Educación, haciendo referencia a la manera en que dicha normativa establece su desarrollo y evaluación. Asimismo, presenta la finalidad del TFG, las diferentes partes en que se estructura y las posibles modalidades por las que se puede optar. Propone, igualmente, pistas para su elaboración y defensa y facilita recursos que pueden ayudar y orientar al alumnado que enfrenta la realización de este trabajoES
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