Tuning the Catalytic Activity of a Pincer Complex of Rhodium(I) by Supramolecular and Redox Stimuli.

We report the rhodium(I) complex [Rh(CNC-NDI)(CO)]+ , in which CNC-NDI refers to a pincer-CNC ligand decorated with a naphthalenediimide moiety. Due to the presence of the planar CNC ligand and the naphthalenediimide moiety, the electronic nature of the complex can be modulated by means of supramolecular and redox stimuli, respectively. The metal complex shows a strong π-π-stacking interaction with coronene. This interaction has an impact on the electron-richness of the metal, as demonstrated by the shifting of the ν(CO) stretching band to a lower frequency. The addition of tetrabutylammonium fluoride facilitates the sequential one- and two-electron reduction of the NDI moiety of the ligand, thus resulting in a situation in which the ligand can increase its electron-donor strength in two levels. The nature of the interaction with the fluoride anion was studied computationally. The catalytic activity of the [Rh(CNC-NDI)(CO)]+ complex was tested in the cycloisomerization of alkynoic acids, where it is observed that the activity of the catalyst can be modulated between four levels of activity, which correspond to i) the use of the unmodified catalyst, ii) catalyst+coronene, iii) catalyst+2 equivalents of fluoride, and iv) catalyst+5 equivalents of fluoride.

Supramolecular Control of the Oxidative Addition as a Way To Improve the Catalytic Efficiency of Pincer-Rhodium (I) Complexes.

1 H NMR studies using a cationic complex with a pyridine-di-imidazolylidene pincer ligand of formula [Rh(CNC)(CO)]+ revealed that this compound showed high binding affinity with coronene in CH2 Cl2 . The interaction between coronene and the planar RhI complex is established by means of π-stacking interactions. This interaction has a strong impact on the electron-donating strength of the pincer CNC ligand, which is increased significantly, as demonstrated by the shifting of the ν(CO) stretching bands to lower frequencies. The addition of coronene increases the reaction rate of the nucleophilic attack of methyl iodide on the rhodium (I) pincer complex, and also has a positive effect on the performance of the complex as a catalyst in the cycloisomerization of 4-pentynoic acid. These findings highlight the importance of supramolecular interactions for tuning the reactivity and catalytic activity of square-planar metal complexes.

Terapia de conducta: raíces, evolución y reflexión sobre la vigencia delconductismo en el contexto clínico / Behavior therapy: roots, evolution, and reflection on the relevance of behaviorism in the clinical context

La Terapia de Conducta, así como sus tres generaciones, ha mostrado ser la tecnología psicoterapéutica con mayor evidencia empírica en psicología clínica y de la salud. Sin embargo, cada una de estas generaciones parte de unas bases filosóficas diferentes. En este trabajo se presenta brevemente su recorrido histórico, sus puntos fuertes y los posibles inconvenientes que nos encontramos en cada una. En primer lugar, el Conductismo (metodológico y radical) y sus diversas técnicas basadas en los principios del aprendizaje, seguido por el surgir de las Terapias Cognitivo-Conductuales en un contexto histórico marcado por el cognitivismo y siendo, a día de hoy, las más eficaces para una amplia variedad de casuísticas. Por último, las denominadas Terapias de Tercera Generación (o Contextuales), tecnología derivada del contextualismo funcional que sienta la base de estas. Como conclusiones, se recoge la relevancia del debate sobre cuál es el objeto de estudio de la psicología y se remarca la adherencia a los Tratamientos Psicológicos Basados en la Evidencia.(AU)

Behavior Therapy—as well as its three generations—has been shown to be the psychotherapeutic technology with the most empirical evidence in clinical and health psychology. However, each of its generations is based on different philosophical foundations. In this paper, we briefly present their historical background, their strengths, and the possible drawbacks that we find in each one. First, behaviorism (methodological and radical) and its various techniques based on the principles of learning, followed by the emergence of cognitive-behavioral therapies in a historical context marked by cognitivism and, today, the most effective technique for a wide variety of cases. Finally, those known as third generation (or contextual) therapies, a technology derived from functional contextualism that is the basis of these therapies. As conclusions, the relevance of the debate surrounding the object of study of psychology and the adherence to evidence-based psychological treatments is highlighted.(AU)