ceverelst

From problem set to puzzle game

Synlett
DOI: 10.1055/a-2384-7220

For hundreds of years, it seems that people have needed stirring to conduct chemical experiments. This operation can be seen everywhere in chemical, pharmaceutical, and materials laboratories and factories. People generally believe that stirring helps with processes such as material dispersion, dissolution, and collision, thereby enabling more-efficient reactions. However, why do chemical reactions that occur in Nature not require stirring? What are the facts? For this purpose, we investigated a total of 329 organic chemical reactions in eight categories and 25 types, including 26 chemical reactions magnified to gram or even kilogram levels. Under the same conditions of temperature, humidity, pressure, and reaction time, we compared the reaction yields under stirring and standing conditions. More than 600 results showed that stirring or not stirring had almost no effect on the efficiency of chemical reactions in solution. If most chemists performing reactions turned off the agitator, it would not be difficult to imagine how much electricity could be saved!
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Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, Germany

Article in Thieme eJournals:
Table of contents  |  Abstract  |  Full text

Nature, Published online: 27 November 2024; doi:10.1038/d41586-024-03858-5

Study participants rated fictional scientists who admitted their own knowledge gaps as more credible.

Methanol, a cheap and readily available resource from chemical industry, could be activated by transition metal catalysts. In the field of methanol activation, many new synthetic methods have been developed for efficient methanol utilization as C1 building block in methylation, hydromethylation, aminomethylation, formylation reactions, as well as the syntheses of urea derivatives and heterocycles. This review discusses the achievements, synthetic applications, limitations, some advanced techniques, and future perspectives of the methanol activation methodologies.

Abstract

The development of efficient and sustainable chemical processes which use greener reagents and solvents, currently play an important role in current research. Methanol, a cheap and readily available resource from chemical industry, could be activated by transition metal catalysts. This review focuses in covering the recent five-years literature and provides a systematic summary of strategies for methanol activation and the use in organic chemistry. Based on these strategies, many new synthetic methods have been developed for methanol utilization as the C1 building block in methylation, hydromethylation, aminomethylation, formylation reactions, as well as the syntheses of urea derivatives and heterocycles. The achievements, synthetic applications, limitations, some advanced approaches, and future perspectives of the methanol activation methodologies have been described in this review.

We present a hydrogen isotope exchange reaction using non-directed homogeneous Pd-catalysis. The catalytic system relies on a commercially available pyridine ligand that enables aromatic C−H activation. Labelling of 39 pharmaceuticals was achieved by utilizing D₂O as the deuterium source and solvent, without requiring fluorinated cosolvents. Expansion to T/H exchange on three different pharmaceuticals by using T₂O as isotopic source was demonstrated.

Abstract

Deuterated and tritiated analogs of drugs are valuable compounds for pharmaceutical and medicinal chemistry. In this work, we present a novel hydrogen isotope exchange reaction of drugs using non-directed homogeneous Pd-catalysis. Aromatic C−H activation is achieved by a commercially available pyridine ligand. Using the most convenient and cheapest deuterium source, D₂O, as the only solvent 39 pharmaceuticals were labelled with clean reaction profiles and high deuterium uptakes. Additionally, we describe the first application of non-directed homogeneous Pd-catalysis for H/T exchange on three different pharmaceuticals by using T₂O as isotopic source, demonstrating the applicability to the synthesis of radiotracers.

Generating common fluorinating agents directly from the mineral avoids the dangers of hydrogen fluoride

A Python script for the systematic, high-throughput analysis of accurate mass data was developed and tested on over 3,000 Supporting Information (SI) PDFs from Organic Letters. For each SI file, quadruplets of molecular formula, measured ion, e.g. [M+Na]+, reported calculated and found masses were extracted and analyzed. Interestingly, only one third of the files containing readable accurate mass data were found to be both internally consistent and in compliance with The ACS Guide to Scholarly Communication. The analysis revealed unex¬pected errors and provides actionable advice on how to improve data quality.

Nature, Published online: 12 November 2024; doi:10.1038/d41586-024-03176-w

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Nature, Published online: 05 November 2024; doi:10.1038/d41586-024-03494-z

A hefty paper published in Nature has raised the question of whether data-dense research tomes can still be digestible.

Nature, Published online: 28 October 2024; doi:10.1038/d41586-024-03477-0

Researchers can craft their own polished, professional figures and images with the help of these tools and design principles.

Nature, Published online: 23 October 2024; doi:10.1038/d41586-024-03461-8

Five researchers from around the world share advice for helping students and their mentors benefit from short-term internships.

The Cover Feature depicts the conversion of second-generation biomass into 5-(halomethyl)furfurals (XMFs), highlighting sustainable pathways to replace fossil resources and address environmental challenges. It symbolizes a greener world through circular chemistry, showcasing innovation in using renewable resources for a cleaner chemical industry. More information can be found in the Review by G.-J. M. Gruter and co-workers.

Nature, Published online: 14 October 2024; doi:10.1038/d41586-024-03343-z

More than 1,100 research leaders from 77 countries told Nature about where and how they recruit scientists — and who makes the cut.

Nature, Published online: 09 October 2024; doi:10.1038/d41586-024-03217-4

Do you have a favourite tool or workaround that helps you save time, money or drudgery? Share it with Nature’s readers.

Nature, Published online: 01 October 2024; doi:10.1038/d41586-024-03136-4

PhD students in Sweden accessed mental-health services at increasing rates as their studies went on.

Suit claims collusion against researchers, but some experts doubt its merits

Studies of inebriated worms, dead trout, and pigeon pilots were all winners