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Science, Volume 389, Issue 6762, Page 766-766, August 2025.

Pt, Ni, and Pt–Ni/HY catalysts were prepared through mechanochemistry, without solvent. Upon optimization of the milling parameters, Pt–Ni/HY showed improved catalytic performance with less metal contents, which can be attributed to an improved metal distribution and interaction with the acid sites of HY zeolite.

Abstract

The global need to decrease CO₂ emissions led to the exploration of biomass-based fuels. However, the need to upgrade bio-oil through hydrodeoxygenation (HDO) reaction led to the search for more effective and environmentally sustainable bifunctional catalysts. Mechanochemistry, without any solvent, was chosen as a method to prepare metal-loaded (Pt, Ni, or both Pt–Ni) HY catalyst for the hydrodeoxygenation of guaiacol, which was used as model molecule. Under optimized milling conditions of 30 min and 200 rpm, the simultaneous addition of Pt and Ni allowed to reduce the metal contents when compared with solely Pt- or Ni-loaded catalysts, with improved catalytic performance for the hydrogenation of guaiacol. This can be attributed to the favorable effect of the mechanochemistry approach used to introduce the metallic function, reducing the size of zeolite clusters and promoting an effective metal dispersion, which is expected to favor the interactions of the metal sites with the more accessible acid sites in the zeolite.

A low-cost method for fabricating leak-proof electrochemical flow reactors that can withstand high internal pressures is developed using selective Pt electroplating (5 μm thick) and chemical bonding methods. These findings may increase interest in electrochemical flow synthesis and lead to the industrial application of this approach.

The use of precious metal electrodes, although capable of improving reaction efficiency, inevitably increases the fabrication cost of electrochemical flow reactors. Additionally, the commonly employed mechanical fastening method consistently poses a risk of leakage. Herein, a low-cost method for fabricating leak-proof electrochemical flow reactors that can withstand high internal pressures is reported using electroplating and chemical bonding methods. By selectively electroplating Pt only on the electrode portion where the electrochemical reaction occurs, the Pt usage on the electrode is reduced by up to 99.4% (selective electroplating of 5-μm-thick Pt = 0.077 g vs. 0.2-mm-thick sheet of Pt = 13.8 g). The reactor shows no liquid leakage, even at a high pressure of 320 psi, and is composed of materials with excellent chemical resistance; therefore, various organic solvents and compounds can be used without restriction. Additionally, the reactor performance is verified by confirming a high yield of up to 88% in the CH/SH cross-coupling reaction. Compared with that of conventional mechanical fastening methods, the fabrication cost is reduced by 97.4%. In addition, this process enables easy fabrication of a reactor of any shape. These findings may increase interest in electrochemical flow synthesis and lead to the industrial application of this approach.

Nature, Published online: 06 August 2025; doi:10.1038/d41586-025-02472-3

Most people can get enough protein from food, but certain groups can benefit from protein powders and related products.

Nature, Published online: 06 August 2025; doi:10.1038/d41586-025-02457-2

Journals and funders are trying to boost the speed and effectiveness of review processes that are under strain.

This study investigates a sustainable alernative to Bisphenol A synthesized via acetalization of vanillin and erythritol using zeolite catalysts. Among the tested zeolites, mordenite (SiO₂/Al₂O₃ = 40) exhibited the highest yield of 90%. The catalyst efficiency depends on the accessibility of external Bronsted acid sites. The catalyst demonstrated excellent recyclability, highlighting its potential use in sustainable industrial Bisphenol A alternatives.

Bisphenol A (BPA), a key monomer used in polymer production, poses significant health and environmental risks, necessitating the need for sustainable alternatives. This study establishes a sustainable route for BPA alternatives via the acetalization of biomass-derived vanillin and erythritol using industrially relevant zeolite catalysts. Among various homogeneous and heterogeneous Brønsted and Lewis acid catalysts tested, heterogeneous mordenite zeolite (SiO₂/Al₂O₃ = 40) achieves the highest BPA derivative yield (90%). Kinetic studies confirm a consecutive reaction mechanism, with the hemiacetal-to-acetal step being the rate-determining step. The catalyst is recyclable and maintains stable performance over five consecutive runs. Detailed structural characterizations, reactant accessibility studies, conditional experiments, and probe molecule tests reveal that a higher external surface area, Brønsted acid sites on the external surface, and greater hydrophobicity are key to the zeolite's high efficiency. These features facilitate the adsorption and desorption of large reactant and product molecules, circumventing pore-diffusion limitations while evading byproduct water-induced deactivation. This study not only demonstrates the use of industrial zeolites for sustainable BPA derivatives from biorenewables but also highlights critical structural and compositional parameters for optimizing catalyst design. Also, the findings provide a framework for rationalizing zeolite-based catalysts for a broad range of biobased BPA alternatives.

Privileged chiral catalysts have transformed asymmetric synthesis, conferring generality to processes that are routinely leveraged in the construction of societally important functional small molecules. This mini-review is intended to survey the conception and evolution of privileged chiral photocatalyst scaffolds that enable simultaneous orchestration of reactivity and enantioselectivity in non-ground state regimes.

Abstract

Privileged chiral catalysts have transformed asymmetric synthesis, conferring generality to processes that are routinely leveraged in the construction of societally important functional small molecules. Operating in the ground state, these catalysts are conspicuous in their ability to simultaneously regulate reactivity and translate chiral information, often with broad substrate tolerance: this technology continues to expedite chemical space exploration. In stark contrast to the specificity of many enzymatic transformations, this promiscuity affords remarkable latitude for creative endeavour in synthesis. Given the transformative impact that stereoselective photocatalysis has had over the last decade, identifying privileged chiral catalysts that permit reactivity and enantioselectivity to be regulated in excited-state scenarios has emerged as an attractive but challenging frontier. Providing solutions to address this paradox will require the reactivity/selectivity divide to be reconciled through the validation of chiral scaffolds that effectively operate in non-ground state environments. Inspired by the venerable treatment by Yoon and Jacobsen entitled “Privileged chiral catalysts” (Science 2003, 299, 1691–1693), this mini-review is intended to survey the conception and evolution of privileged chiral photocatalyst scaffolds, and offer a perspective on emerging contenders.

Nature, Published online: 24 July 2025; doi:10.1038/d41586-025-01627-6

It took time and rejections to understand what granting agencies look for. This is how I picked up application-writing skills.

The Cover Feature shows a sustainable, solvent-free strategy for closed-loop recyclable acetal thermosets. Bio-based vanillin derivatives and diols are combined under bulk conditions by using oxalic acid as a green catalyst, yielding thermosets with excellent mechanical properties. These materials can be efficiently closed-loop recycled in high yield and reformed into new thermosets, offering a circular solution for high-performance engineering applications. More information can be found in the Research Article by Ž. Tomović and co-workers (DOI: 10.1002/cssc.202500163).

Biogenic materials naturally containing trace metals such as Celite or diatomaceous earth promote practical perfluoroalkylation of C─H bonds of (hetero)arenes and a double bond bromination with N-bromosuccinimide upon mechanoactivation via ball milling. This conceptually broadens the scope of mechanoactivated solids beyond piezoelectric materials. This approach poses an advancement towards sustainable processes, as it demonstrates the new application of non-toxic, untreated biominerals.

Abstract

Herein, we report that Celite (diatomaceous earth) commonly viewed as an innocent filter aid or support material, or Earth-abundant, non-toxic metal oxides are efficient mechanoactivated catalysts for arene and heteroarene C─H bond radical trifluoromethylation and pentafluoroethylation, with the activity comparable with previously reported mechanochemical methods utilizing piezoelectric materials. Celite was also applied for mechanochemical dibromination of a double bond with N-bromosuccinimide, eliminating the need to use of lithium titanate as a piezoelectric mechanoredox catalyst. Mechanoactivation via ball milling in the presence of minimal amount of solvent was crucial to observe the reactivity, while sonication or using a pre-ground suspension in a bulk solvent were not efficient. The EDX studies and comparison with individual metal oxides suggest a possible role of trace metal oxides in mechanoinduced reactivity. Celite could be recycled and reused several times without significant loss of activity. This approach offers environmentally benign, biocompatible and inexpensive nature-inspired materials as efficient mechanocatalyts and conceptually broadens the scope of mechanoactivated solids to the materials previously deemed inert.

Fossil fuels have long powered industries and transportation, but their depletion and environmental impact have driven the search for renewable alternatives like biomass. Levulinic acid (LA), derived from lignocellulosic biomass, can be converted into valuable products such as gamma valerolactone (GVL). GVL which can be used as solvent and for synthesis of sustainable fuels and polymers. Ruthenium-based catalysts, particularly Ru/C, are effective in hydrogenating LA to GVL but face challenges like metal leaching and catalyst degradation. To address this, researchers are improving catalyst stability through nitrogen-doped carbon supports and embedding strategies, however most of them involves tedious synthesis and expensive and non-renewable chemicals. In this work, we synthesized a stable, efficient ruthenium catalyst supported on carbon from biomass-derived chitosan without using additional nitrogen dopants, aiming to enhance its performance in LA hydrogenation. The Ru catalyst supported on N-doped carbon from chitosan pyrolysis at 700 °C, exhibited superior activity, stability, and recyclability for LA hydrogenation to GVL, outperforming conventional Ru/C and shows comparable activity with other reported Ru catalysts. Characterization by XPS and H₂-TPR revealed strong metal-support interactions facilitated by nitrogen functionalities, which stabilized ruthenium species in both reduced and oxidized states. Graphitic nitrogen species in the catalyst were decisive in the controlling the catalytic activity also maintaining a fine balnace between different nitrogen species and N-content was the key to synthesize suitable supports from chitosan. A proposed reaction mechanism highlights the role of Ru-N centers in facilitating hydrogen and LA activation and hydrogenation step, with basic nitrogen sites (pyridinic and pyrrolic nitrogen) aiding in the dehydration step to form GVL. Overall, this work features the potential of chitosan derived carbon as a sustainable and tunable support for designing efficient catalysts for biomass hydrogenation and the findings provide fundamental insights into the role of nitrogen doping in enhancing catalytic performance.