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Our study unveils a pioneering methodology that effectively distributes Pd species within a zeolitic imidazolate framework‐8 (ZIF‐8). We demonstrate that Pd can be encapsulated within ZIF‐8 as atomically dispersed Pd species that function as an excited‐state transition metal catalyst for promoting carbon–carbon (C−C) cross‐couplings at room temperature using visible light as the driving force. Furthermore, the same material can be reduced at 250 °C, forming Pd metal nanoparticles encapsulated in ZIF‐8. This catalyst shows high rates and selectivity for carbon dioxide hydrogenation to methanol under industrially relevant conditions (250 °C, 50 bar): 7.46 molmethanol molmetal−1 h−1 and >99 %. Our results demonstrate the correlations of the catalyst structure with the performances at experimental and theoretical levels. [ABSTRACT FROM AUTHOR]

Advancements in fine chemical synthesis and drug discovery continuously demand the development of new and more efficient catalytic systems. In this regard, numerous transition metal-based catalysts have been developed and successfully applied in industrial processes. However, the need for innovative catalyst systems to further enhance the efficiency of chemical transformations and industrial applications persists. Metal nanoclusters (NCs) represent a distinct class of ultra-small nanoparticles (<3 nm) characterized by a precise number of metal atoms coordinated with a defined number of ligands. This structure confers abundant unsaturated active sites and unique electronic and optical properties, setting them apart from conventional nanoparticles or bulk metals. The well-defined structure and monodisperse nature of NCs make them particularly attractive for catalytic applications. Among these, copper-based nanoclusters have emerged as versatile and sustainable catalysts for challenging organic bond-forming reactions. Their unique properties, including natural abundance, accessible oxidation states, diverse ligand architectures, and strong photophysical characteristics, contribute to their growing prominence in this field. In this review, we discuss the photocatalytic activities of Cu-based nanoclusters, focusing on their applications in cross-coupling reactions (C–C and C–N), click reactions, multicomponent couplings, and oxidation reactions. [ABSTRACT FROM AUTHOR]

In recent years, mechanochemistry has become recognized as an efficient, practical, and sustainable alternative for chemical synthesis. Adhering to the principles of green chemistry, mechanochemistry enables solvent-free, faster, and energy-efficient reactions, thereby reducing waste production and enhancing atom economy. Herein, we present a new nickel-catalyzed mechanochemical High Throughput Experimentation (HTE) amination protocol enabled by Resonant Acoustic Mixing (RAM). The developed C–N cross-coupling reactions avoid possible contamination, scaling-up challenges, and parallel reaction limitations by applying an accelerated screening and optimization protocol. The reduced amount of solvents in the reactions and the minimal amount of reagents required highlight the advantages of our approach over most common solvent-based reactions, aligning with the principles of sustainability and resource efficiency. Furthermore, the mechanochemistry methodology demonstrates seamless scalability to a multigram scale without additional optimizations, emphasizing its potential for streamlined, environmentally friendly, and large-scale industrial production. [ABSTRACT FROM AUTHOR]

Extremophilic proteins are valuable in various fields, but their expression can be challenging in traditional hosts like Escherichia coli due to misfolding and aggregation. Haloferax volcanii (H. volcanii), a halophilic expression system, offers a solution. This study examined cleavable and non-cleavable purification tags at both the N- and C-termini when fused with the superfolder green fluorescent protein (sfGFP) in H. volcanii. Our findings reveal that an N-terminal 8xHis-tag or Strep-tag®II significantly enhances protein production, purity, and yield in H. volcanii. Further experiments with mCherry and halophilic alcohol dehydrogenase (ADH) showed improved expression and purification yields when the 8xHis-tag or Strep-tag®II was positioned at the C-terminus for mCherry and at the N-terminus for ADH. Co-positioning 8xHis-tag and Twin-Strep-tag® at the N-terminus of sfGFP, mCherry, and ADH yielded significantly enhanced results. These findings highlight the importance of thoughtful purification tag design and selection in H. volcanii, providing valuable insights for improving protein production and purification with the potential to advance biotechnological applications. [ABSTRACT FROM AUTHOR]

We have developed a novel Ni-catalyzed reductive cross-coupling reaction of aryl bromides and alkyl iodides via a photoactive electron donor–acceptor (EDA) complex. This photo-induced process enables the efficient construction of C(sp2)–C(sp3) bonds in the absence of an external photocatalyst. Electronically and structurally diverse aryl bromides, as well as secondary and primary alkyl iodides could undergo this transformation smoothly. Natural product derivatives were employed successfully, and UV-vis spectroscopy was utilized to gain mechanistic insight. [ABSTRACT FROM AUTHOR]

A new cross‐coupling of trifluoromethyl arenes has been realized via multiphoton photoredox catalysis. Trifluoromethyl arenes were demonstrated to undergo selective mono‐defluorinative alkylation under mild reaction conditions providing access to a series of valuable α,α‐difluorobenzylic compounds. The reaction shows broad substrate scope and general functional group tolerance. In addition to the electron‐deficient trifluoromethyl arenes that are easily reduced to the corresponding radical anion, more challenging electron‐rich substrates were also successfully applied. Steady‐State Stern‐Volmer quenching studies indicated that the trifluoromethyl arenes were reduced by the multiphoton excited Ir‐based photocatalyst. [ABSTRACT FROM AUTHOR]

The development of an electrochemical cobalt catalyzed C-Cl bond activation at room temperature for the nucleophilic addition of aryl and vinyl chlorides to α-ketoamides is described. The overall method operates through an electrochemically induced low valent cobalt catalyst that oxidatively adds to aryl or vinyl chlorides affording medicinally important 3-hydroxy oxindole and 3-hydroxypyrrolidinone scaffolds. The development of an enantioselective version using a chiral pyrox ligand is also demonstrated. [ABSTRACT FROM AUTHOR]

During the COVID‐19 pandemic, the use of polypropylene fleece‐based personal protection equipment (PPE) increased significantly to over ten million tons. Typically, most PPEs are discarded after a single use, to prevent self‐infection of users and spread of infectious agents. However, in order to minimize plastic waste without compromising the protective properties of PPE, it is crucial to explore new reusable or longer‐lived materials. Here, a visible light‐activatable antimicrobial photodynamic dye coating for PPEs is presented. In this context, coating with thiomorpholino‐methylene blue (TMB), derived from methylene blue by introducing two thiomorpholine units, is found to show high antibacterial activity. TMB is integrated into rotary printing suspension, a commercial nitrocellulose‐based printing matrix. The concentration of TMB in adhesive is optimized, and found that 5% TMB is suitable for coating PPE, for reducing the number of Gram‐positive and ‐negative bacteria by 99.99% after 6 h of white light irradiation. Bacterial filtration efficiency and breathability tested according to EN 14683, confirmed that TMB coating does not affect the filter performance. Thus, this antimicrobial photodynamic dye coating technique offers a promising solution for a safer and extended use of PPE, and reduction of plastic waste generated by PPEs. [ABSTRACT FROM AUTHOR]