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Polar solvents promote halogen bonds over hydrogen ones

05 Jul 2017

Solvent effects control competition between hydrogen bonding and halogen bonding in supramolecular systems, new research shows. The upshot of the finding is a potential new tool to direct supramolecular self-assembly.

During self-assembly, each molecule breaks its bonding interactions with neighbouring solvent molecules, then forms new interactions. To investigate competition between hydrogen bonding and halogen bonding when co-crystals form, researchers from an ongoing collaboration between the UK Universities of Sheffield, York and Cambridge chose seven solvents of different polarities to study three aromatic molecules known to self-assemble. The molecules’ functional groups included pairs of hydrogen bond and halogen bond donors that compete for a common acceptor group.

Solvent plays a critical role in directing self-assembly

Read the full story by Fiona Tscherny on Chemistry World.

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Light-driven catalytic process offers greener route to organic alcohols

26 Jun 2017

Researchers in Spain have developed a light-driven catalytic process that offers a greener way to produce organic alcohols – important compounds used to manufacture pharmaceuticals and pesticides.

Researchers have developed a catalytic system to reduce aromatic ketones and both aliphatic and aromatic aldehydes that uses earth-abundant metals and light.

Read the full story by Jamie Durrani on Chemistry World.

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First +5 praseodymium compound with PrN triple bond made

16 May 2017

The first pentavalent praseodymium nitride–oxide that features a rare Pr≡N triple bond is the second ever lanthanide(V) complex to be made.

Lanthanide chemistry is dominated by the +3 oxidation state. There are some common +4 lanthanide complexes such as cerium oxide (CeO2), but +5 compounds have proven elusive. Praseodymium has long been considered as the most promising route to lanthanide(V) chemistry as it has five valence electrons, but the first pentavalent praseodymium complex, the oxide PrO2+, was only synthesised last year.

Source: © Royal Society of Chemistry
Calculations led to these representations of the molecular orbitals of the praseodymium(V) compound, NPrO

Read the full story by Aurora Walshe on Chemistry World.

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15-minute test catches out flu virus

19 Apr 2017

A team in the US has designed a test for detecting influenza viruses in just 15 minutes using a glucose meter – a cheap, handheld instrument that is widely available.

Source: © Royal Society of Chemistry
Proteins sitting on the flu viruses’ surface cleave a carbon–oxygen bond in a modified sialic acid, releasing the sugar galactose

Suri S Iyer and colleagues from Georgia State University have now designed a test to detect influenza viruses A and B in just 15 minutes. The test only requires a nasal swab and a glucose meter – a simple instrument usually used for diabetes control. ‘Influenza virus can be deadly especially in weak or immunocompromised people. This diagnostic can help these people as vaccines for flu are not perfect,’ Iyer explains.

Read the full story by Adrian Robinson on Chemistry World.

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Molecular suit provides basic protection

19 Apr 2017

Scientists have designed a macrocycle that can completely surround a small molecule like a suit and protect it from a strong base. This reversible suiting strategy could find applications as protecting groups in organic synthesis and the design of molecular machines.

Source: © Royal Society of Chemistry
The suit-1-ane: a macrocycle (orange) completely encloses a benzimidazolium cation (blue)

Protecting groups alter the reactivity of organic molecules by shielding functional groups from other reactants. Mechanically interlocked molecules (MIMs) are linked structures that require a covalent bond to be broken to separate them, which could make them useful protecting groups.

Read the full story by Harriet Brewerton on Chemistry World.

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Tamed radicals expand chemical space

31 Mar 2017

A method to functionalise complex molecules with catalytic radicals could expand chemical libraries of the drug and agrochemical industry

Source: © Royal Society of Chemistry Even complex molecules like the anti-cancer drug camptothecin (top left) can be modified using Molander’s radical alkylation

US scientists have developed a visible-light mediated reaction that uses tamed alkyl radicals to functionalise complex molecules. This mild and selective method could allow chemists to explore new corners of chemical space and to discover new drugs and agrochemicals.

Read the full story by Jessica Dwyer on Chemistry World.

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Neural network provides accurate simulations without the cost

21 Mar 2017

An efficient new computer brain can provide quick answers to computational chemistry problems

A computer that has been taught about organic chemistry can describe the forces in molecules as accurately as density functional theory (DFT), but hundreds of thousands of times faster. This combination of speed and accuracy could allow researchers to tackle problems that were previously impossible.

Chemists hoping to use computer simulations face a dilemma. Researchers commonly need to know the energy of a molecule, and the forces that control how it twists and bends. Accurate methods like DFT, which use quantum mechanics, take the most computer power and time. Approximations such as semi-empirical methods give faster but less reliable results. Although there is a spectrum of options, most techniques ask researchers to trade off speed and accuracy.

Read the full story by Alexander Whiteside on Chemistry World.

Source: © Royal Society of Chemistry
The neural network can predict molecular energies hundreds of thousands of times faster than DFT

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Outstanding Reviewers for Chemical Science in 2016

24 Feb 2017

Following the success of Peer Review Week in September 2016 (dedicated to reviewer recognition) during which we published a list of our top reviewers, we are delighted to announce that we will continue to recognise the contribution that our reviewers make to the journal by announcing our Outstanding Reviewers each year.

We would like to highlight the Outstanding Reviewers for Chemical Science in 2016, as selected by the editorial team, for their significant contribution to the journal. The reviewers have been chosen based on the number, timeliness and quality of the reports completed over the last 12 months.

We would like to say a big thank you to those individuals listed here as well as to all of the reviewers that have supported the journal. Each Outstanding Reviewer will receive a certificate to give recognition for their significant contribution.

Professor Atsushi Fukuoka, Hokkaido University

Dr Gilles Gasser, Chimie ParisTech, PSL Research University

Professor Dirk Guldi, Friedrich Alexander Universität

Dr Christian Hackenberger, Leibniz-Institut für Molekulare Pharmakologie im Forschungsverbund Berlin e.V. (FMP)

Dr Takashi Hisatomi, The University of Tokyo

Dr Paul Knochel, Ludwig-Maximilians-Universität

Professor Jun Kubota, Fukuoka University

Professor Stefan Matile, Universite de Geneve

Professor Frank Wuerthner, Universitaet Wuerzburg

Professor Juyoung Yoon, Ewha Womans University

We would also like to thank the Chemical Science board and the General Chemistry community for their continued support of the journal, as authors, reviewers and readers.

If you would like to become a reviewer for our journal, just email us with details of your research interests and an up-to-date CV or résumé. You can find more details in our author and reviewer resource centre

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First observation of unusual hemi bond

07 Feb 2017

Experimental evidence for two-centre three-electron bond described as ‘a triumph of spectroscopy’

Researchers in Japan have observed the stable hemi-bonded structure of (H2S)n+ (n = 3–6). Using infra-red (IR) spectroscopy, the team has experimental evidence for this unusual, previously only theoretically predicted, structure.

The two-centre three-electron (2c–3e) bond, also known as a hemi bond, was first proposed by Linus Pauling in the 1930s. It is formed by the lone pair orbitals of a neutral molecule and its radical cation overlapping, causing the bonding sigma orbital to be doubly occupied and the antibonding sigma* orbital to be singly occupied.

Read the full story by Suzanne Howson on Chemistry World.

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Stabilization of the world’s smallest lasso

07 Feb 2017

Molecular snare threads through itself under redox conditions

The world’s smallest lasso has been created by scientists in Saudi Arabia and the US. The molecular device threads through itself, forming a reversible noose, in response to chemical and electronic stimuli.

The research team, led by 2016 Nobel prize-winner Fraser Stoddart of Northwestern University, were inspired by naturally occurring lasso peptides – molecules produced by a variety of bacteria, which consist of a linear peptide tail laced through a macrolactam ring.

Read the full story by Jamie Durrani on Chemistry World.

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