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Free Radical Chemistry themed issue in memory of Athel Beckwith

Professor Athel Beckwith who inspired a generation of free radical chemists

View the Free Radical Chemistry web themed issue

It was a stunned international chemistry community that learnt of the tragic death of Athel Beckwith on 15 May 2010. As word spread, shock and disbelief were the overwhelming sentiments; the world had lost a scientific treasure.

Athel Beckwith was born in Perth on 20 February 1930. His father was a pharmacist and both of his parents were gifted musicians, a trait passed on to Athel at an early age. He attended Perth Modern School where he excelled. He matriculated with Distinction in all seven subjects and went on to the University of Western Australia for his chemical education. It was during his undergraduate studies that Athel learnt that the most interesting chemistry occurs when there is an unexpected outcome and that it is through these unexpected outcomes that we learn new things. These are principles that he passed on to his students during his academic career including myself.

Athel spent his Honours year working on natural product chemistry under the guidance of Doug White, and later on reaction mechanisms with Joe Miller. After a period as a graduate assistant he moved to Adelaide to take up a position as a junior lecturer, but eventually doctoral studies lured Athel to Oxford where he worked with Professor Waters on relatively unknown entities known as “free radicals”, a “wise choice” according to Athel.

After a year at Imperial College on a Nuffield Foundation grant he returned to Adelaide where he established a research group working on free radicals and shortly after became Professor of Organic Chemistry at the age of 35. This was a very important period in the development of free radical chemistry and led to “Beckwith’s Rules” for predicting the outcomes of free radical cyclization reactions. In 1981 he moved to the Australian National University where he remained until his retirement in 1995.

I know of only three reactions that are named after Australian chemists (Birch, Liepa and Beckwith–Dowd) and, it is significant that they all involve free radicals. It was carrying out a Birch reduction as an undergraduate that swayed me toward chemistry and eventually free radicals and I was fortunate to work under Athel’s guidance during my PhD studies. Athel was at the cutting edge of free radical chemistry during what I have referred to as the “Free Radical Renaissance Period” and others have called the “Golden Age” during which the factors that govern radical chemistry were being teased out to provide guidelines that we now all take for granted. His contributions to the understanding of factors that govern the region- and stereo-selectivity of radical reactions are profound and enduring and established Australia as a major hub of activity in the field, a hub that several of his “academic children” have inherited. He also made significant contributions to radical clock reactions, nitroxide chemistry, the neophyl and other rearrangements, ESR spectroscopy, as well as other chemistries.

I have tried to model my role as supervisor to his “scientific grandchildren” on the principles that he taught me; even if I perform my role to only a fraction of Athel’s ability, I would consider that to be a great achievement. In addition to being a brilliant scientist, Athel was always kind, a gentleman and a scholar in the truest sense, a wonderful human being.  Further information about Athel can be found in a recent interview for the Australian Academy of Science (http://www.science.org.au/scientists/interviews/b/ab.html).

It has been a pleasure to be the guest editor of this special free radical themed issue of Organic & Biomolecular Chemistry dedicated to Athel. It is timely that the latest free radical chemistry be showcased in such a manner, and I am confident that Athel would have appreciated reading each of the cutting-edge articles presented in this special issue. Fittingly, a diversity of radical chemistry from around the world is represented in this issue, of which about 25% of articles have been flagged as being HOT. The overwhelmingly positive responses from members of the international free radical community to invitations to contribute to this issue is a measure of the fondness and esteem that Athel Beckwith was held in and I thank each of you for making this issue such a success.  I also thank the Team at Organic & Biomolecular Chemistry, in particular Lorena Tomas Laudo, Roxane Owen and Richard Kelly for their professional expert assistance, guidance and good humour.

Carl Schiesser – Guest Editor

 

Carl Schiesser is Professor of Chemistry in the School of Chemistry at The University of Melbourne and Director of the Australian Research Council Centre of Excellence for Free Radical Chemistry and Bio­technology. He received his PhD in 1987 from the Australian National University working with Professor Athel Beckwith and was a postdoc with Professor Alwyn Davies at University College London from 1988–1990. Professor Schiesser received a DSc from the University of Adelaide in 2000 and was awarded the prestigious A. J. Birch medal of the Royal Australian Chemical Institute in 2006.  Carl is a Fellow of the Royal Australian Chemical Institute and the Royal Society of Chemistry. He has extensive experience in free radical chemistry, ranging from molecular modelling, through to mechanistic and kinetic studies, the development of new chemical methodology, synthesis of bioactive molecules and cultural materials conservation.

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OBC themed issue on foldamer chemistry – Call for papers

OBC is delighted to announce a high-profile web theme focussing on foldamer chemistry. Submissions are now open.

This online theme issue will be published at the end of 2011. Submissions of communications and full papers can be made at any time but must be received by the editorial office by 15 August 2011 for peer review.

Submission and tracking of manuscripts can be done directly online at http://mc.manuscriptcentral.com/ob. Submissions should indicate in the “comments to the editor” section that they are for the foldamers web theme.

You can view other, recently published OBC web themes at http://pubs.rsc.org/en/journals/journalissues/ob#!themedissues

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OBC Issue 11 published!

Check out the cover articles in Organic & Biomolecular Chemistry Issue 11.

The outside cover features work by Michael Doyle and colleagues  at University of Maryland. They talk about catalytic C-H insertion processes in comparison with other approaches for the synthesis of selected synthetic targets, lactones and lactams, which have been of biological or medicinal interest. It is a very interesting and original review article. Read more at

Intramolecular catalytic asymmetric carbon–hydrogen insertion reactions. Synthetic advantages in total synthesis in comparison with alternative approaches
Michael P. Doyle, Maxim Ratnikov and Yu Liu
Org. Biomol. Chem., 2011, 9, 4007-4016
DOI: 10.1039/C0OB00698J

The inside cover represents how Aminoglycoside acetyltransferase AAC(6’) belonging to the aminoglycoside-modifying enzymes (AMEs) does not deactivate the 6’-N-glycinyl tobramycin which attacks the bacterial ribosome (green arrow). In contrast, the parent aminoglycoside tobramycin cannot pass through bacterial resistance mechanism (red arrow).
You can read more about this article by Micha Fridman, Sylvie Garneau-Tsodikova and co-workers at Michigan and Tel Aviv at

Assessment of 6′- and 6′′′-N-acylation of aminoglycosides as a strategy to overcome bacterial resistance
Pazit Shaul, Keith D. Green, Roi Rutenberg, Maria Kramer, Yifat Berkov-Zrihen, Elinor Breiner-Goldstein, Sylvie Garneau-Tsodikova and Micha Fridman
Org. Biomol. Chem., 2011, 9, 4057-4063
DOI: 10.1039/C0OB01133A

Both articles are FREE to download until the end of June.

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Cascade reactions and multiple rings – OBC emerging area

Cascade or domino processes have become one of the Holy Grails in organic synthesis. They allow the sequential formation of multiple new bonds and therefore, the one-pot synthesis of new and complex organic molecules. 

The formation of new cyclic frameworks in a controlled-one synthetic operation is almost a dream come true for synthetic chemists due to the complexity and challenging structure of these heterocycles.

In this review article, Edward Anderson, at Oxford University, gives us a selective overview of cascade reactions as applied to natural product synthesis. We invite you to download it and read this excellent accounting of recent cascade-based polycyclic reactions towards the synthesis of natural products.

Cascade polycyclisations in natural product synthesis
Edward A. Anderson
Org. Biomol. Chem., 2011, Advance Article
DOI: 10.1039/C1OB05212H, Emerging Area

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Catalytic asymmetric C-H insertions-OBC perspective

Asymmetric catalytic intramolecular carbon-hydrogen insertion reactions are pivotal reactions in the world of organic chemistry and there is a considerable amount of literature on this topic.

Michael Doyle and his colleagues at University of Maryland, have now written a very original and different review on the catalytic C-H insertion process in comparison with other approaches for the synthesis of selected synthetic targets, lactones and lactams, which have been of biological or medicinal interest. They discuss these well-defined targeted molecules for which there have been multiple examples of their synthesis. They conclude by saying that the catalytic route through chiral dirhodium(II) carboxamidates is the most appropriate method for the stereoselective carbon–hydrogen insertion reactions that produce biologically relevant lactones and lactams.

If you want to find out more about the different synthetic approaches and the advantges of using one over the other, download this very interesting review.

Intramolecular catalytic asymmetric carbon–hydrogen insertion reactions. Synthetic advantages in total synthesis in comparison with alternative approaches
Michael P. Doyle, Maxim Ratnikov and Yu Liu
Org. Biomol. Chem., 2011, Advance Article
DOI: 10.1039/C0OB00698J, Perspective

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HOT: Monitoring intracellular copper levels in living cells

Copper is an essential trace element in the physiology of living organisms as many critical proteins and enzymes contain copper in their active sites or/and require copper for their activities.
Disruption of copper levels in cells can cause diseases such as Menkes syndrome, Wilson’s disease, amyotrophic lateral sclerosis and Alzheimer’s. Therefore, the quantitative detection of intracellular copper could help with the understanding of its complex physiological and pathological roles.

Unlike other trace metals such as zinc, iron, chromium and mercury, which can be successfully detected with rhodamine-based fluorescence probes, the detection of copper has proven to be more challenging and the development of satisfactory fluorescent probes needs addressing.

Bao-Xiang Zhao, Jun-Ying Miao and colleagues at Shandong University in China have now developed a rhodamine chromene-based fluorescence probe to monitor the intracellular levels of copper in living cells. The probe switches to a highly fluorescent complex upon coordination with copper under physiological conditions in a very sensitive and selective manner and facilitates the naked-eye detection of the metal.

If you want to learn more about this satisfactory fluorescent probe I invite you to download this paper that is free to access until 15th June.

Synthesis, crystal structure and living cell imaging of a Cu2+-specific molecular probe
Wei-Yong Liu, Hai-Ying Li, Bao-Xiang Zhao and Jun-Ying Miao
Org. Biomol. Chem., 2011, Advance Article
DOI: 10.1039/C1OB05358B

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HOT: One electron oxidation of substituted ferrocenes

How can the structure of short-lived N-oxyl radicals influence its electron transfer (ET) properties?

Osvaldo Lanzalunga and his team at Sapienza Universita di Roma and Istituto CNR di Metodologie Chimiche (IMC-CNR) provide some answers to this question in this OBC HOT paper.

They study the kinetics of the one electron oxidation of substituted ferrocenes by a series of N-oxyl radicals in acetonitrile and determine self-exchange reorganization energy values.
They conclude by saying that ‘even small modifications of the structure of the N-oxyl radicals lead to signifiant variation of the self-exchange reorganization energy values.’

If you want to read more about these results, you can download the paper for free until 8th June.

This paper is part of the Free Radical collection of papers in memory of Athel Beckwith, which will be published at the end of May. Watch this space.

One-electron oxidation of ferrocenes by short-lived N-oxyl radicals. The role of structural effects on the intrinsic electron transfer reactivities
Enrico Baciocchi, Massimo Bietti, Claudio D’Alfonso, Osvaldo Lanzalunga, Andrea Lapi and Michela Salamone
Org. Biomol. Chem., 2011, Advance Article
DOI: 10.1039/C0OB01257B

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Most cited OBC Emerging Areas free to download!

The OBC editorial team has collected the most cited Emerging Areas published in our journal in the last 5 years. You can now download them for free!

Emerging Areas are short, forward-looking feature articles on particularly topical subjects. These articles are generally submitted following invitation; however the editorial team are happy to consider suggestions for review articles. If you have an idea for a review topic please contact the Editor.

Find below the top 5 most cited emerging areas in the last 5 years. Congratulations to the authors and thanks!

Asymmetric organocatalysis
Jayasree Seayad and Benjamin List
Org. Biomol. Chem., 2005, 3, 719-724
DOI: 10.1039/B415217B

The golden gate to catalysis
Anja Hoffmann-Röder and Norbert Krause
Org. Biomol. Chem., 2005, 3, 387-391
DOI: 10.1039/B416516K

σ-Chelation-directed C–H functionalizations using Pd(II) and Cu(II) catalysts: regioselectivity, stereoselectivity and catalytic turnover
Jin-Quan Yu, Ramesh Giri and Xiao Chen
Org. Biomol. Chem., 2006, 4, 4041-4047
DOI: 10.1039/B611094K

A hitchhiker’s guide to G-quadruplex ligands
David Monchaud and Marie-Paule Teulade-Fichou
Org. Biomol. Chem., 2008, 6, 627-636
DOI: 10.1039/B714772B

“Frustrated Lewis pairs”: a concept for new reactivity and catalysis
Douglas W. Stephan
Org. Biomol. Chem., 2008, 6, 1535-1539
DOI: 10.1039/B802575B

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Good TEMPO-H for OBC! Highlighted in C&EN

Congratulations to Jason Clyburne and colleagues at Saint Mary’s University in Canada are in order!

Their recent Organic & Biomolecular Chemistry HOT article on ‘Anhydrous TEMPO-H: reactions of a good hydrogen atom donor with low-valent carbon centres’ has been highlighted in C&EN this month (May).

If you want to read the story just click below:
Going Anhydrous modifies TEMPO-H

We are delighted to see such a great coverage and promotion of this very interesting article. You can now download it for free until 14th May here!

Thanks to our colleagues in C&EN for a nice story on the article.

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Effect of substituents on the stabilities of radicals-OBC Cover Issue 10

Leo Radom and collaborators in Australia and Switzerland present in this paper a thorough computational study, which correlates with experimental data, of the stability of a very large series of multiply-substituted carbon-centered radicals. They look at the stabilization and interaction energies and the deviations from additivity of RSEs.

The cover image depicts how the stabilities of multiply-substituted carbon-centered radicals are compared with the stabilities of their monosubstituted components. The factors that influence the effect of substituents on such a comparison are discussed.

This article will be included in the OBC special issue in memory of Athel Beckwith: Free Radical Chemistry. Coming soon.

Effect of substituents on the stabilities of multiply-substituted carbon-centered radicals
Ambili S. Menon, David J. Henry, Thomas Bally and Leo Radom
Org. Biomol. Chem., 2011, Advance Article
DOI: 10.1039/C1OB05196B

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