Scalable Synthesis and Electrocatalytic Performance of Highly Fluorinated Covalent Organic Frameworks for Oxygen Reduction.

In this study, we present a novel approach for the synthesis of covalent organic frameworks (COFs) that overcomes the common limitations of non-scalable solvothermal procedures. Our method allows for the room-temperature and scalable synthesis of a highly fluorinated DFTAPB-TFTA-COF, which exhibits intrinsic hydrophobicity. We used DFT-based calculations to elucidate the role of the fluorine atoms in enhancing the crystallinity of the material through corrugation effects, resulting in maximized interlayer interactions, as disclosed both from PXRD structural resolution and theoretical simulations. We further investigated the electrocatalytic properties of this material towards the oxygen reduction reaction (ORR). Our results show that the fluorinated COF produces hydrogen peroxide selectively with low overpotential (0.062 V) and high turnover frequency (0.0757 s-1 ) without the addition of any conductive additives. These values are among the best reported for non-pyrolyzed and metal-free electrocatalysts. Finally, we employed DFT-based calculations to analyse the reaction mechanism, highlighting the crucial role of the fluorine atom in the active site assembly. Our findings shed light on the potential of fluorinated COFs as promising electrocatalysts for the ORR, as well as their potential applications in other fields.

Hexaazatriphenylene (HAT) derivatives: from synthesis to molecular design, self-organization and device applications.

Dipyrazino[2,3-f:2',3'-h]quinoxaline also known as 1,4,5,8,9,12-hexaazatriphenylene (HAT) is an electron deficient, rigid, planar, aromatic discotic system with an excellent π­π stacking ability. Because it is one of the smallest two-dimensional N-containing polyheterocyclic aromatic systems, it has been used as the basic scaffold for larger 2D N-substituted polyheterocyclic aromatics. Furthermore, it is the building block of choice in a plethora of molecular, macromolecular and supramolecular systems for a variety of applications. This review is aimed to critically review the research performed during the almost three decades of research based on HAT from the synthetic, theoretical and application points of view. The design principles and synthetic strategies towards HAT derivatives will be established and their use in n-type semiconductors, sensors, nonlinear optical chromophores, liquid crystals, microporous polymers for energy storage and nano and microstructures will reveal the relevance of HAT as a basic scaffold in the areas of organic materials and nanoscience.

Culture and psychiatric evaluation: operationalizing cultural formulation for DSM-5.

The Outline for Cultural Formulation (OCF) introduced with DSM-IV provided a framework for clinicians to organize cultural information relevant to diagnostic assessment and treatment planning. However, use of the OCF has been inconsistent, raising questions about the need for guidance on implementation, training, and application in diverse settings. To address this need, DSM-5 introduced a cultural formulation interview (CFI) that operationalizes the process of data collection for the OCF. The CFI includes patient and informant versions and 12 supplementary modules addressing specific domains of the OCF. This article summarizes the literature reviews and analyses of experience with the OCF conducted by the DSM-5 Cross-Cultural Issues Subgroup (DCCIS) that informed the development of the CFI. We review the history and contents of the DSM-IV OCF, its use in training programs, and previous attempts to render it operational through questionnaires, protocols, and semi-structured interview formats. Results of research based on the OCF are discussed. For each domain of the OCF, we summarize findings from the DCCIS that led to content revision and operationalization in the CFI. The conclusion discusses training and implementation issues essential to service delivery.

Hexaazatriphenylene (HAT) versus tri-HAT: the bigger the better?

A new hexaazatriphenylene (HAT) derivative formed by the fusion of three HAT units has been prepared and its electronic and molecular structures have been fully characterized by optical and vibrational Raman spectroscopy, electrochemistry, solid-state UV and inverse photoemission spectroscopy (UPS and IPES), and by quantum-chemical calculations. A comparative HAT versus tri-HAT study was performed. The fusion of three HAT molecules causes modifications in the optical and electrochemical properties consistent with enhanced π-electron delocalization attained in a bigger planar core. Such combined experimental and theoretical studies are useful to balance chemical design with supramolecular engineering directed to find enhanced characteristics for new organic semiconductor applications.

Synthesis and electrochemical and theoretical studies of V-shaped donor-acceptor hexaazatriphenylene derivatives for second harmonic generation.

In this article we describe novel synthetic strategies toward well-defined disubstituted conjugated hexaazatriphenylene (HAT) derivatives. The systems are designed as novel V-shaped chromophores displaying C2 symmetry suitable for nonlinear optical investigations. Different donor moieties and linkers have been used in order to tune the electrochemical properties as well as the absorption spectra of the novel HAT derivatives. µß values as high as 1010 × 10(-48) esu have been obtained for a derivative containing the electron-rich dibutylamino moiety. Theoretical calculations have been performed showing a reasonable agreement with the experimental results and supporting the two-dimensional NLO character of these chromophores.

Studies on striatal neurotoxicity caused by the 3,4-methylenedioxymethamphetamine/ malonate combination: implications for serotonin/dopamine interactions.

The amphetamine derivative 3,4-methylenedioxymethamphetamine (MDMA) produces long-term toxicity to serotonin (5-HT) neurones in rats, which is exacerbated when combined with the mitochondrial inhibitor malonate. Moreover, MDMA, which does not produce dopamine depletion in the rat, potentiates malonate-induced striatal dopamine toxicity. Because the malonate/MDMA combination acutely causes a synergistic increase of 5-HT and dopamine release, in this study we sought to determine whether pharmacological blockade of MDMA- and/or malonate-induced dopamine release prevents neurotoxicity. Fluoxetine, given 30 min prior to the malonate/MDMA combination, afforded complete protection against 5-HT depletion and reversed MDMA-induced exacerbation of dopamine toxicity found in the malonate/MDMA treated rats. Protection afforded by fluoxetine was not related to changes in MDMA-induced hyperthermia. Similarly, potentiation of malonate-induced dopamine toxicity caused by MDMA was not observed in p-chlorophenylalanine-5-HT depleted rats. Finally, the dopamine transporter inhibitor GBR 12909 completely prevented dopamine neurotoxicity caused by the malonate/MDMA combination and reversed the exacerbating toxic effects of malonate on MDMA-induced 5-HT depletion without significantly altering the hyperthermic response. Overall, these results suggest that the synergic release of dopamine caused by the malonate/MDMA combination plays an important role in the long-term toxic effects. A possible mechanism of neurotoxicity and protection is proposed.