Ewoud

Nature, Published online: 21 January 2025; doi:10.1038/d41586-025-00130-2

If one animal urinates, others are likely follow, according to a study of captive apes.

Nature, Published online: 20 January 2025; doi:10.1038/d41586-024-04253-w

Survey of more than 1,600 biomedical researchers also flagged small sample sizes and cherry-picking of data as leading causes of reproducibility problems.

A low-cost, operationally simple approach to seven different solventless Rh-, Ru-, Ir- and Pd-catalyzed C–H and C–X functionalizations, as well as the synthesis of difficult-to-make rhodacyclic complexes, is presented. The method uses open air grinding and heating, is reproducible, gives competitive yields compared with automated ball milling protocols, and can be extended to the late-stage modification of various bioactive compounds.

Nature Communications, Published online: 17 January 2025; doi:10.1038/s41467-025-56138-9

Accidental ingestion of Pb-contaminated soils represents a major route of Pb exposure for humans. Here, the authors show an effective and straightforward approach of drinking cola beverages to reduce blood Pb levels following the ingestion of contaminated soils based on animal models data.

Nature, Published online: 10 January 2025; doi:10.1038/d41586-025-00027-0

Meta’s planned shift away from third-party fact-checking on Facebook in favour of a crowdsourced approach has perplexed those who study the spread of misinformation.

Publication date: 8 May 2025

Source: Chem, Volume 11, Issue 5

Author(s): Shijie Deng, Hyuk-Joon Jung, Yi Shen, Hootan Roshandel, Varit Chantranuwathana, Hieu D. Nguyen, Thi V. Tran, Kimberly Vasquez, Joseph Chang, Takeo Iwase, Parisa Mehrkhodavandi, Jeffery A. Byers, Loi H. Do, Paula L. Diaconescu

Cyclodextrin-mediated aqueous biphasic systems are a potent way to recycle homogeneous catalysts, also applicable to producing highly demanded renewable chemical intermediates. Based on a sophisticated batch optimization, a total STY of 76.5 kg/h/m³ was achieved in a continuously operated miniplant with minimal leaching of 0.018 %/h.

Abstract

Platform chemicals from renewable resources with broad applications are highly desirable, particularly for replacing fossil-based monomers. Bifunctional aliphatic ester-aldehydes, accessible via regioselective hydroformylation of unsaturated oleochemicals, can be converted into linear ω-amino/ω-hydroxy esters and dicarboxylic acids—key building blocks for biobased aliphatic polycondensates. However, their success hinges on efficient, economically viable production, with catalyst recycling being critical. We present the Rh-catalyzed, cyclodextrin-mediated, aqueous biphasic hydroformylation of methyl 10-undecenoate (from castor oil) and methyl 9-decenoate (from rapeseed oil) to produce methyl 12-oxododecanoate and methyl 11-oxoundecanoate, respectively, with high yields and productivity. This system allows for efficient catalyst recycling via decantation, maintaining 30 % of its native activity in aqueous biphasic conditions. Reaction conditions were optimized using a tailored experimental design, reducing nearly 200 experiments to 39 without sacrificing predictive accuracy. The optimized conditions were transferred to a continuous miniplant, achieving a low rhodium loss of 0.018 % h⁻¹, with excellent space-time yields of 76.5 kg h⁻¹ m⁻³. Rhodium in the product was as low as 79 ppb, with 4.4 kg of product per mg of catalyst lost, marking a significant step in combining hydroformylation-derived, bio-based platform chemicals with economic industrial potential.

Hydrodeoxygenation (HDO) is an effective method for upgrading bio-oil by removing oxygen, saturating aromatic compounds, and improving its calorific value. HDO requires hydrogen, which can be supplied externally or through supercritical fluids acting as hydrogen donors. Hydrogen-donor solvents, particularly ethanol and methanol derived from biomass, are promising due to their renewable nature and ability to provide active hydrogen.

Abstract

Upgrading bio-oil is crucial for the use of renewable fuels in the transportation sector. Hydrodeoxygenation (HDO) is a key technology for upgrading bio-oil and removing oxygen in the form of water, typically under pressurized hydrogen. However, the use of high-pressure hydrogen is limited by several factors (e.g., storage safety issues). This review primarily discusses the substantial advantages of catalytic HDO in supercritical fluids, which overcome the need for external H₂ while providing a wider range of products. In particular, this study focuses on ethanol and methanol as effective H-donor solvents for HDO processes due to their ability to provide active hydrogen under relatively mild conditions, along with their multifunctionality as both solvents and H-donors and their potential to enhance mass- and heat-transfer efficiencies. Guaiacol was chosen as the HDO feedstock because it can be found abundantly in bio-oil. Furthermore, the effects of the catalyst properties (e.g., pore size, acidity, and acidic and metallic site distribution) and reaction conditions on the reaction efficiency and product distribution are discussed. This review also describes technical challenges, proposes solutions, and outlines future research directions for advancing the supercritical HDO processes with the aim of guiding future studies toward more effective and sustainable HDO-based biofuel-upgrading technologies.

By using either monophosphine ligand based on 2,3-dihydrobenzo[d][1,3]oxaphosphole motif or bidentate ligand Ph-Phox, the regioselective alkoxycarbonylations of aryl-aryl, aryl-alkyl and alkyl-alkyl disubstituted alkynes are achieved, giving a diversity of trisubstituted α,β-unsaturated carboxylic esters with moderate to excellent yields and high regioselectivity.

Abstract

Pd-catalyzed alkoxycarbonylation of internal alkynes provides a straightforward access to α,β-disubstituted acrylic esters. Compared with the well-established regioselective alkoxycarbonylation of terminal alkynes, the regioselective hydrocarboxylation of non-functionalized unsymmetric internal alkynes was more challenging owing to the delicate differences of properties between the two substituents. Herein, by using either monophosphine ligand based on 2,3-dihydrobenzo[d][1,3]oxaphosphole motif or bidentate ligand Ph-Phox, the regioselective alkoxycarbonylations of aryl-aryl, aryl-alkyl and alkyl-alkyl disubstituted alkynes were achieved, giving a diversity of trisubstituted α,β-unsaturated carboxylic esters with moderate to excellent yields and high regioselectivity. The synthetic utility of obtained α,β-disubstituted acrylic esters was demonstrated.

Increasing bio-based and circular components in polyurethane formulation up to 65 %w/w maintaining the market acceptability through multivariate analysis approach

Abstract

In this contribution, we tackle the replacement of the Hg-based catalyst and fossil-derived isocyanate precursors toward the formulation of a more sustainable polyurethane thermosetting resins (PUs), emulating the performance of a fully fossil-based one employed in industrial encapsulation of optoelectronics. A mixed Bi−Zn catalyst and a 71 % bio-based isocyanate are exploited at this aim through multivariate chemometric approaches, namely Design of Experiment (DoE). DoE allows us to investigate the effect of different formulation factors on selected parameters, such as the film flexibility and transparency or the gel time. More in detail, it is found that a low amount of Zn-rich catalytic mixture leads to a ready-to-market polyurethane only when a fossil-based isocyanate is used. Differently, PUs formulated with bio-based isocyanate, albeit showing a higher bio-based content, present an insufficient optical purity, jeopardizing their market acceptability. Nevertheless, adding a negligible amount of a specific long chain fatty acid as reactivity modulator in the formulation leads to a bubbles-free and ready-to-market resin showing an impressive 65 % w/w content of circular and bio-based components.

This Minireview describes the most recent advances in carbonylative transformations involving heteroatom adjacent carbon radicals, specifically including the heteroatoms oxygen (O), nitrogen (N), phosphorus (P), silicon (Si), sulfur (S), boron (B), fluorine (F), and chlorine (Cl). The reaction mechanisms are also described in detail.

Abstract

Heteroatoms are essential to living organisms and present in almost all molecules with medicinal usage. The catalytic functionalization at the carbon-centered radical with an adjacent heteroatom provides an effective way to value added moiety while retaining the unique physicochemical and pharmacological properties of heteroatoms, which can promote the development of pharmaceutical and fine chemical production. Carbonylative transformation was discovered nearly a century ago which is an efficient method for the synthesis of carbonyl-containing molecules with potent applications in both industry and academia. Despite numerous advances in new reaction development, carbonylative transformation involving adjacent heteroatom carbon radical remain a subject that deserves to be discussed. In this minireview, we systematically summarized and discussed the recent advances in carbonylative transformations involving carbon-centered radicals with an adjacent heteroatom, including oxygen (O), nitrogen (N), phosphorus (P), silicon (Si), sulfur (S), boron (B), fluorine (F), and chlorine (Cl). The related reaction mechanism was also discussed.

The last 15 years publications on alkenes alkoxycarbonylation with alcohols and CO using homogeneous catalytic systems (based on Pd, Ru, Co, and Ni) in the absence of strong H-acids commonly used in these reactions were analyzed. As a result of these works, polyesters, monomers, and other valuable intermediates were obtained.

Abstract

Alkoxycarbonylation represents a method for the ester products synthesis from available reagents – unsaturated compounds, alcohols, and CO. The beginning of research on this reaction was laid in W. Reppe’ works in 1953. In early works, halides and carbonyls of Co, Ni, Rh, and Ir were used as catalysts, and alkoxycarbonylation was often complicated by the unsaturated compounds hydroformylation or alcohol carbonylation. In recent decades, in the presence of the most active and selective Pd-phosphine systems with strong protonic acids, the products are typically only isomeric esters, which corresponds to the creating waste-free production principles. At present, a large-capacity synthesis process for methyl methacrylate, dubbed Alpha, is in operation, with the initial stage being ethylene methoxycarbonylation. In light of these developments, there is a growing interest among chemists and technologists in alkenes alkoxycarbonylation. The use of strong protonic acids as co-catalysts is essential for the formation of active catalytic complexes. However, these acids are highly corrosive and can cause the alkenes isomerisation. This review is devoted to the analysis of acid-free homogeneous Pd-, Ru-, Co-, and Ni-catalysts employed in alkenes alkoxycarbonylation over the past 15 years. As a result, polymers, monomers and other valuable linear and branched esters were obtained.