The Golden Age of Thermally Activated Delayed Fluorescence Materials: Design and Exploitation.

Since the seminal report by Adachi and co-workers in 2012, there has been a veritable explosion of interest in the design of thermally activated delayed fluorescence (TADF) compounds, particularly as emitters for organic light-emitting diodes (OLEDs). With rapid advancements and innovation in materials design, the efficiencies of TADF OLEDs for each of the primary color points as well as for white devices now rival those of state-of-the-art phosphorescent emitters. Beyond electroluminescent devices, TADF compounds have also found increasing utility and applications in numerous related fields, from photocatalysis, to sensing, to imaging and beyond.

Functionalization of monolithic MOF thin films with hydrocarbon chains to achieve superhydrophobic surfaces with tunable water adhesion strength.

While the accessible pores render an enormous variety of functionalities to the bulk of metal-organic frameworks (MOFs), the outer surfaces exposed by these crystalline materials also offer unique characteristics not available when using conventional substrates. By grafting hydrocarbon chains to well-defined MOF thin films (SURMOFs) prepared using layer-by-layer methods, we were able to fabricate superhydrophobic substrates with static water contact angles over 160°. A detailed theoretical modelling of the hydrocarbon chains grafted on the outer SURMOF surface with well-defined spacing between anchoring points reveals that the grafted hydrocarbon chains behave similarly to polymer brushes during wetting, where conformational entropy is traded with mixing entropy.

Drug retention after intradiscal administration.

Intradiscal drug delivery is a promising strategy for treating intervertebral disk degeneration (IVDD). Local degenerative processes and intrinsically low fluid exchange are likely to influence drug retention. Understanding their connection will enable the optimization of IVDD therapeutics.

Modulating the photolysis of aryl azides in a supramolecular host to develop photoactivatable fluorophores.

Photolysis of aryl azides is a convenient method to approach more functionalized systems in chemical biology. Here, we present a set of photoactivatable aryl azides that undergo controlled reaction pathways within the cucurbit[7]uril (CB7) cavity upon photolysis. The fluorescence turn-on process is utilized for bioimaging.

A simple method to modulate the selectivity of aryl azide photolysis using cucurbit[8]uril.

Photolysis of aryl azides typically involves multiple reaction pathways. This study designed and synthesized an aryl azide rotamer with two conformations. In aqueous media, its photolysis yields two main products.

Zinc Phthalocyanine Core-First Star Polymers Through Nitroxide Mediated Polymerization and Nitroxide Exchange Reaction.

Nitroxide-mediated polymerization (NMP) and nitroxide exchange reaction (NER) are very efficient methodologies that require only suitable alkoxyamine derivatives and create different polymeric architectures in a controlled manner. Herein, the synthesis of star polymers containing TEMPO-substituted symmetric zinc phthalocyanine (ZnPc) is presented via NMP and NER. Moreover, linear polymer formation is conducted in a single arm on TEMPO-substituted asymmetric ZnPc to elucidate the properties of star polymers.

H-driven biocatalysis for flavin-dependent ene-reduction in a continuous closed-loop flow system utilizing H from water electrolysis.

Despite the increasing demand for efficient and sustainable chemical processes, the development of scalable systems using biocatalysis for fine chemical production remains a significant challenge. We have developed a scalable flow system using immobilized enzymes to facilitate flavin-dependent biocatalysis, targeting as a proof-of-concept asymmetric alkene reduction. The system integrates a flavin-dependent Old Yellow Enzyme (OYE) and a soluble hydrogenase to enable H-driven regeneration of the OYE cofactor FMNH.

Thermally Activated Delayed Fluorescence (TADF) Materials Based on Earth-Abundant Transition Metal Complexes: Synthesis, Design and Applications.

Materials exhibiting thermally activated delayed fluorescence (TADF) based on transition metal complexes are currently gathering significant attention due to their technological potential. Their application extends beyond optoelectronics, in particular organic light-emitting diodes (OLEDs) and light-emitting electrochemical cells (LECs), and include also photocatalysis, sensing, and X-ray scintillators. From the perspective of sustainability, earth-abundant metal centers are preferred to rarer second- and third-transition series elements, thus determining a reduction in costs and toxicity but without compromising the overall performances.

Heterocyclic Hemipiperazines: Multistimuli-Responsive Switches and Sensors for Zinc or Cadmium Ions.

Advance in the design of molecular photoswitches - adapters that convert light into changes at molecular level - opens up exciting possibilities in preparing smart polymers, drugs photoactivated inside humans, or light-fueled nanomachines that might in the future operate in our bloodstream. Hemipiperazines are recently reported biocompatible molecular photoswitches based on cyclic dipeptides. Here we report a multistimuli-responsive hemipiperazine-based switch that reacts on light, solvents, acidity, or metal ions.

A New Class of Chiral Polyethers and Polyesters Based on the [2.2]Paracyclophane Scaffold.

Over the past decades, the research on optically active polymers (OAPs) has significantly grown, and extensive studies have been carried out on their syntheses, conformations, and applications. The most commonly used OAPs are based on natural products such as sugars or amino acids, which limits their scope. A broader range of applications can be achieved by synthesizing lab-tailored monomers, which allow precise control over structure and properties.

Correction: 3D printing of reactive macroporous polymers thiol-ene chemistry and polymerization-induced phase separation.

Correction for '3D printing of reactive macroporous polymers thiol-ene chemistry and polymerization-induced phase separation' by Nikolaj K. Mandsberg , , 2024, https://doi.org/10.

Benign synthesis of terpene-based 1,4-p-menthane diamine.

Terpenes represent a promising renewable feedstock for the substitution of fossil resources in the synthesis of renewable platform chemicals, like diamines. This work describes the synthesis and full characterization of 1,4-p-menthane diamine (1,4-PMD) obtained from α-terpinene (1). A two-step procedure using dibenzyl azodicarboxylate (DBAD) and H as rather benign reagents was employed under comparatively mild conditions.

3D printing of reactive macroporous polymers thiol-ene chemistry and polymerization-induced phase separation.

Using thiol-ene chemistry, polymerization-induced phase separation, and DLP 3D printing, we present a method for manufacturing reactive macroporous 3D structures. This approach enables the fabrication of structures with tunable physicochemical properties and compressibility. Moreover, it facilitates post-functionalization through thiol-Michael addition reactions, thereby expanding performance and application potential.

Synthesis of Mono-, Di-, Tri-, and Tetra-cationic Pyridinium and Vinylpyridinium Modified [2.2]Paracyclophanes: Modular Receptors for Supramolecular Systems.

In this report, a new series of mono-, di-, tri-, and tetra-cationic pyridinium and vinyl pyridinium-modified [2.2]paracyclophanes as useful molecular tectons for supramolecular systems are described. Regioselective functionalization at specific positions, followed by resolution step and successive transformations through Pd-catalyzed Suzuki-Miyaura and Mizoroki-Heck cross-coupling chemistry furnish a series of modular PCP scaffolds.

Reversing the stereoselectivity of intramolecular [2+2] photocycloaddition utilizing cucurbit[8]uril as a molecular flask.

Macrocyclic hosts, such as cucurbit[8]uril (CB8), can significantly influence the outcomes of chemical reactions involving encapsulated reactive guests. In this study, we demonstrate that CB8 completely reverses the stereoselectivity of intramolecular [2+2] photo-cycloaddition reactions. Notably, it was also found that CB8 can trigger the unreactive diene to be reactive.

Optimized Detection of Volatile Organic Compounds Utilizing Durable and Selective Arrays of Tailored UiO-66-X SURMOF Sensors.

Metal-organic frameworks (MOFs), with their well-defined and highly flexible nanoporous architectures, provide a material platform ideal for fabricating sensors. We demonstrate that the efficacy and specificity of detecting and differentiating volatile organic compounds (VOCs) can be significantly enhanced using a range of slightly varied MOFs. These variations are obtained via postsynthetic modification (PSM) of a primary framework.

From Mono- to Polynuclear 2-(Diphenylphosphino)pyridine-Based Cu(I) and Ag(I) Complexes: Synthesis, Structural Characterization, and DFT Calculations.

A series of monometallic Ag(I) and Cu(I) halide complexes bearing 2-(diphenylphosphino)pyridine (PyrPhos, L) as a ligand were synthesized and spectroscopically characterized. The structure of most of the derivatives was unambiguously established by X-ray diffraction analysis, revealing the formation of mono-, di-, and tetranuclear complexes having general formulas (M = Cu, X = Cl, Br; M = Ag, X = Cl, Br, I), (X = Cl, Br), and (X = Cl, Br, I). The Ag(I) species were compared to the corresponding Cu(I) analogues from a structural point of view.

Modulating Aryl Azide Photolysis: Synthesis of a Room-Temperature Phosphorescent Carboline in Cucurbit[7]uril Host.

Cucurbit[7]uril (CB7), a supramolecular host, is employed to control the pathway of photolysis of an aryl azide in an aqueous medium. Normally, photolysis of aryl azides in bulk water culminates predominantly in the formation of azepine derivatives via intramolecular rearrangement. Remarkably, however, when this process unfolds within the protective confinement of the CB7 cavity, it results in a carboline derivative, as a consequence of a C─H amination reaction.

Selectivity control towards CO versus H for photo-driven CO reduction with a novel Co(II) catalyst.

Developing efficient catalysts for reducing carbon dioxide, a highly stable combustion waste product, is a relevant task to lower the atmospheric concentration of this greenhouse gas by upcycling. Selectivity towards CO-reduction products is highly desirable, although it can be challenging to achieve since the metal-hydrides formation is sometimes favored and leads to H evolution. In this work, we designed a cobalt-based catalyst, and we present herein its physicochemical properties.

Synthesis of highly substituted alkenes by sulfur-mediated olefination of N-tosylhydrazones.

Tetraphenylethylenes (TPEs) are well-known for their aggregation-induced emission properties. The synthesis of TPE derivatives, as well as other highly substituted olefins, generally requires the use of hazardous reagents, such as metalorganic compounds, to overcome the high activation energies caused by the sterically congested double bond. Herein, we present an efficient and metal-free procedure for the synthesis of tetraarylethylenes via alkylidene-homocoupling of N-tosylhydrazones, derived from readily available benzophenones, in excellent yields.

Non-isocyanate polyurethanes synthesized from terpenes using thiourea organocatalysis and thiol-ene-chemistry.

The depletion of fossil resources as well as environmental concerns contribute to an increasing focus on finding more sustainable approaches for the synthesis of polymeric materials. In this work, a synthesis route towards non-isocyanate polyurethanes (NIPUs) using renewable starting materials is presented. Based on the terpenes limonene and carvone as renewable resources, five-membered cyclic carbonates are synthesized and ring-opened with allylamine, using thiourea compounds as benign and efficient organocatalysts.

Structure-Property Relationships of Short Chain (Mixed) Cellulose Esters Synthesized in a DMSO/TMG/CO Switchable Solvent System.

Increasing environmental pollution and petroleum resource depletion are important indicators for the necessary and inevitable replacement of fossil-based polymeric materials with more sustainable counterparts. Hence, the development of bio-based materials from renewable resources, such as cellulose, is of great importance. Herein, we introduce a rapid and homogeneous microwave assisted synthesis of high molecular weight (59 kDa ≤ ≤ 116 kDa) short chain (mixed) cellulose esters (CEs) with variable acyl side chain length (2 ≤ ≤ 8) by using a DMSO/TMG/CO switchable solvent system.

Binding affinity-based intracellular drug detection enabled by a unimolecular cucurbit[7]uril-dye conjugate.

Label-free fluorescence-based chemosensing has been increasingly brought into focus due to its simplicity and high sensitivity for intracellular monitoring of molecules. Currently used methods, such as conventional indicator displacement assays (IDAs), pose limitations related to dissociation upon dilution, random diffusion of the released indicators, and high sensitivity to interference by agents from the ambient cellular environment (, salts, enzymes, and proteins). Herein we report a potentially widely applicable strategy to overcome the limitations of conventional IDAs by employing a macrocyclic cucurbit[7]uril (CB7) host covalently coupled to a nitrobenzoxadiazole (NBD) fluorescent dye (CB7-NBD conjugate).