Archive for July, 2012

Renewable plasticizer alcohols by formal anti-Markovnikov hydration of terminal branched chain alkenes

Plasticizer alcohols have been synthesised from renewable reagents through a borane-free oxidation/reduction sequence.

Bis(2-ethyl-hexyl) phthalate (DEHP) is one of the most important and widely used industrial plasticizers and is generated from 2-ethyl-1-hexanol (2EH) and phthalic anhydride.  In the process of converting bio-butanol to jet fuels, a significant amount of 2-ethyl-1-hexene is produced as a by-product, and is an attractive feedstock to generate 2EH.  To yield the required 2EH from 2-ethyl-1-hexene, an anti-Markovnikov addition is required. However, the traditional hydroboration method used to achieve this is not ideal for large scale, atom economic production of 2EH.

In this work, Benjamin Harvey and colleagues from the United States Navy-Naval Air Systems Command (NAVAIR) demonstrate an efficient method for formal anti-Markovnikov hydration of 1,1-disubstituted alkenes.  Their approach generates the plasticizer alcohols by the oxidation/hydration/hydrogenation of branched chain alkenes under mild, borane-free conditions.  This process was successfully applied to the production of 2EH from 2-ethyl-1-hexene, and presents an alternative to hydroboration for a challenging subset of hindered olefins.

This article is free to access until the 29th August 2012!  Click on the link below to find out more…

Synthesis of renewable plasticizer alcohols by formal anti-Markovnikov hydration of terminal branched chain alkenes viaa borane-free oxidation/reduction sequence, Benjamin G. Harvey, Heather A. Meylemans and Roxanne L. Quintana, Green Chem., 2012, DOI: 10.1039/C2GC35595G

You may also be interested in this article – free to access for 2 weeks:

Mechanism of efficient anti-Markovnikov olefin hydroarylation catalyzed by homogeneous Ir(III) complexes, Gaurav Bhalla, Steven M. Bischof, Somesh K. Ganesh, Xiang Yang Liu, C. J. Jones, Andrey Borzenko, William J. Tenn, III, Daniel H. Ess, Brian G. Hashiguchi, Kapil S. Lokare, Chin Hin Leung, Jonas Oxgaard, William A. Goddard, III and Roy A. Periana, Green Chem., 2011, 13, 69-81

Keep up-to-date with the latest content in Green Chemistry by registering for our free table of contents alerts.

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Cu-catalysed reductive amination of ketones with anilines using molecular hydrogen

Aromatic and aliphatic ketones reacted with aniline and molecular hydrogen in the presence of an easily available copper catalyst to give amines in high yields.

Reductive amination is one of the most important and effective C-N bond forming reactions and provides a general practical way to access amines.  The reaction commonly involves chemicals which act hydrogen donors to be present, such as silanes and formates.  However, utilizing molecular hydrogen instead would give a much more environmentally and atom-economical reducing agent, would give water as the only by-product.

Here, Matthias Beller and colleagues from the Leibniz-Institute for Catalysis in Rostock, Germany report that simple Cu(OAc)2, an inexpensive and easily available catalyst, could catalyse the reductive amination of a variety of ketones with anilines and molecular hydrogen.  The procedure does not require any complicated ligands or additional acid or base and represents the first example of a catalytic approach using copper and molecular hydrogen for reductive aminations.

This article is free to access until the 24th August 2012!  Click on the link below to find out more…

Copper-catalyzed reductive amination of aromatic and aliphatic ketones with anilines using environmental-friendly molecular hydrogen, Svenja Werkmeister, Kathrin Junge and Matthias Beller, Green Chem., 2012, DOI: 10.1039/C2GC35565E

Keep up-to-date with the latest content in Green Chemistry by registering for our free table of contents alerts.

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Issue 8 of Green Chemistry now online

The latest issue of Green Chemistry is now available online!

The front cover of issue 8 features work by Matthew Fuchter and co-workers from Imperial College London and Pfizer Ltd in Sandwich.  The team developed a route to give allylic alcohols from α,β-unsaturated ketones using calcium triflate to replace cerium(III) chloride.  This procedure also accomplished the regioselective 1,2-reduction of challenging α,β-unsaturated ketones such as 2-cyclopentenone with very good selectivity, and is suitable for the stereoselective reduction of α,β-aziridinyl ketones.

Lanthanide replacement in organic synthesis: Luche-type reduction of α,β-unsaturated ketones in the presence of calcium triflate, Nina V. Forkel, David A. Henderson and Matthew J. Fuchter, Green Chem., 2012, 14, 2129-2132.

The inside front cover highlights work by Man Bock Gu and colleagues from Korea University in Seoul, who report the carbonic anhydrase-assisted formation of biomineralized calcium carbonate crystalline composites (CCCCs).  These materials were shown to be effective biocatalysts retaining 43% of the free carbonic anhydrase esterase activity.  The catalysts were stable for more than 50 days at room temperature, could be recovered easily using magnet-based separation and retained their activity over 10 repeated usages.

Carbonic anhydrase assisted calcium carbonate crystalline composites as a biocatalyst, Ee Taek Hwang, Haemin Gang, Jinyang Chung and Man Bock Gu, Green Chem., 2012, 14, 2216-2220

These articles are free to access for 6 weeks

Keep up-to-date with the latest content in Green Chemistry by registering for our free table of contents alerts!

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Top ten most accessed articles in June

This month sees the following articles in Green Chemistry that are in the top ten most accessed:-

Catalytic conversion of biomass using solvents derived from lignin
Pooya Azadi, Ronald Carrasquillo-Flores, Yomaira J. Pagán-Torres, Elif I. Gürbüz, Ramin Farnood and James A. Dumesic
Green Chem., 2012,14, 1573-1576, DOI: 10.1039/C2GC35203F, Communication

An efficient copper-catalyzed formation of highly substituted pyrazoles using molecular oxygen as the oxidant
Mamta Suri, Thierry Jousseaume, Julia J. Neumann and Frank Glorius
Green Chem., 2012, Advance Article, DOI: 10.1039/C2GC35476D, Paper

Multicomponent reactions in unconventional solvents: state of the art
Yanlong Gu
Green Chem., 2012, Advance Article, DOI: 10.1039/C2GC35635J, Critical Review

Selective conversion of microcrystalline cellulose into hexitols on nickel particles encapsulated within ZSM-5 zeolite
Guanfeng Liang, Haiyang Cheng, Wei Li, Limin He, Yancun Yu and Fengyu Zhao
Green Chem., 2012, Advance Article, DOI: 10.1039/C2GC35685F, Communication

An efficient protocol for palladium-catalyzed ligand-free Suzuki-Miyaura coupling in water
Manoj Mondal and Utpal Bora
Green Chem., 2012, Advance Article, DOI: 10.1039/C2GC35401B, Communication

Evolution of asymmetric organocatalysis: multi- and retrocatalysis
Raffael C. Wende and Peter R. Schreiner
Green Chem., 2012, Advance Article, DOI: 10.1039/C2GC35160A, Critical Review

TBHP/I2-promoted oxidative coupling of acetophenones with amines at room temperature under metal-free and solvent-free conditions for the synthesis of a-ketoamides
Xiaobin Zhang and Lei Wang
Green Chem., 2012, Advance Article, DOI: 10.1039/C2GC35489F, Communication

Copper-catalyzed reductive amination of aromatic and aliphatic ketones with anilines using environmental-friendly molecular hydrogen
Svenja Werkmeister, Kathrin Junge and Matthias Beller
Green Chem., 2012, Advance Article, DOI: 10.1039/C2GC35565E, Communication

A simple and facile Heck-type arylation of alkenes with diaryliodonium salts using magnetically recoverable Pd-catalyst
Buchi Reddy Vaddula, Amit Saha, John Leazer and Rajender S. Varma
Green Chem., 2012, Advance Article, DOI: 10.1039/C2GC35673B, Communication

Efficient catalytic hydrogenation of levulinic acid: a key step in biomass conversion
József M. Tukacs, Dávid Király, Andrea Strádi, Gyula Novodarszki, Zsuzsanna Eke, Gábor Dibó, Tamás Kégl and László T. Mika
Green Chem., 2012, Advance Article, DOI: 10.1039/C2GC35503E, Paper

Why not take a look at the articles today and blog your thoughts and comments below.

Fancy submitting an article to Green Chemistry? Then why not submit to us today or alternatively email us your suggestions.

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Incredible ionic liquids: an article collection

Ionic liquids are pretty self explanatory; they are ionic materials in a liquid state. In a ‘normal’ liquid, interactions are usually governed by Van de Waals or H-bonding forces. In ionic liquids it is ionic bonding interactions which dominate, meaning ionic liquids possess some interesting and unique properties.

The field of ionic liquids grew after Paul Walden’s observations of ethylammonium nitrate in 1914,1 since then the study and use of ionic liquids has grown phenomenally, with applications in analytics, biology, electrochemistry, physical chemistry, engineering, solvents and catalysis.

The academic and industrial interest in ionic liquids has thrown up some remarkable discoveries, particularly in recent years, so to keep you up to date with latest break-through research in the field we have collected these high quality articles which are free to access!*

(more…)

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Putting Green Chemistry into Mobile Apps to Communicate Globally

Screenshot of the Green Solvents App for iPad

Screenshot of the Green Solvents App for iPad

Several new mobile applications (Apps) have been recently released for the Apple iOS platform which incorporate green chemistry concepts. This represents a highly novel way to communicate science and bring green chemistry to a bigger audience, which has not previously been appreciated. We certainly sense there is an untapped audience for these types of applications due to the large number of people who now own a mobile device across all demographics. Green Chemistry related information is generally proprietary and papers on the topic are commonly behind paywalls. Making the information freely available or at low cost is a paradigm shift.

For example, a recent consortium organized by the American Chemical Society Green Chemistry InstituteTM (ACS GCI) Pharmaceutical Roundtable1 currently involves 14 pharmaceutical companies, and has developed a solvent selection guide that is publicly available on their website in the form of a PDF file.2 We have made this solvent selection guide more accessible in the form of a free app called Green Solvents.3, 4 It is delivered as a simple structure look-up guide incorporating all of the selection criteria from the ACS GCI and, in addition, having links out to other useful resources (ChemSpider 5-7 etc.). This app, like most free apps, has a small banner advertisement which does not detract from the content of the app or its usability on a mobile device. Importantly this App was not funded by the ACS or any other organization.

Screenshot of the Open Drug Discovery Teams App for iPad

Screenshot of the Open Drug Discovery Teams App for iPad

Creating the Green Solvents app has also motivated the addition of the process mass intensity (PMI) calculation8 (which is another green chemistry feature), into the Yield101 app9. A third recently developed mobile app connected to green chemistry is the Open Drug Discovery Teams (ODDT) app10, 11. ODDT is a free mobile app intended as a research topic aggregator of science data collected from various sources on the internet such as Twitter and Google Alerts. It exists to facilitate interdisciplinary teamwork and deliver access to information that is highly relevant and focused on the topic areas of interest. Research topics include areas of chemistry and adjacent molecule-oriented biomedical sciences, with an emphasis on those which are most amenable to open research at present. We have focused on green chemistry as a topic due to its potential importance for scientists involved in drug discovery for rare and neglected diseases. There is high attrition in drug discovery, so many compounds will need to be made but only a very small fraction will make it into the clinic and, far less, into the marketplace. It is therefore important to design a green process as early as possible when the cost is lower and the quantities of chemicals made are relatively small compared to when they are dramatically scaled up for manufacturing. We feel these global neglected and rare disease researchers would benefit greatly from being informed about green chemistry principles early on and that this has not been considered by any of the major organizations driving green chemistry initiatives. This app has also been used to visualize the ACS GCI solvent selection guide in a different format as it was Tweeted out to reach an even wider audience for those following the hashtag #greenchemistry. To date we are the only researchers that have created and used mobile apps to communicate green chemistry concepts. We feel this is an area that is ripe for expansion to further educate scientists.

Sean Ekins*
Collaborations in Chemistry, 5616 Hilltop Needmore Road, Fuquay-Varina, NC 27526, U.S.A.
Alex M. Clark
Molecular Materials Informatics, 1900 St. Jacques #302, Montreal, Quebec, Canada H3J 2S1
Antony J. Williams
Royal Society of Chemistry, 904 Tamaras Circle, Wake Forest, NC 27587, U.S.A. 

1. American Chemical Society Green Chemistry InstituteTM Pharmaceutical Roundtable www.acs.org/gcipharmaroundtable
2. Solvent selection guide. http://surveys.acs.org/se.ashx?s=04BD76CC0E5496A7
3. Ekins, S. Green Solvents: From Idea to App in 3 Days. http://www.slideshare.net/ekinssean/green-solvents-app
4. Clark, A. M. Green Solvents. http://www.scimobileapps.com/index.php?title=Green_Solvents
5. ChemSpider. www.chemspider.com
6. Pence, H. E.; Williams, A. J. ChemSpider: An Online Chemical Information Resource. J Chem Educ 2010, 87, 1123-1124.
7. Williams, A. J. Public chemical compound databases. Curr Opin Drug Discov Devel 2008, 11, 393-404.
8. ACS GCI Pharmaceutical Roundtable. http://portal.acs.org/portal/acs/corg/content?_nfpb=true&_pageLabel=PP_TRANSITIONMAIN&node_id=1422&use_sec=false&sec_url_var=region1&__uuid=46aca9b6-a985-42cd-a534-7d6cabf892a7
9. Clark, A. M. Yield-101. http://www.scimobileapps.com/index.php?title=Yield101
10. Ekins, S.; Clark, A. M.; Williams, A. J. Open Drug Discovery Teams: A Chemistry Mobile App for Collaboration. Molecular Informatics 2012, In Press.
11. Philippidis, A. App connects rare disease researchers to data. http://www.genengnews.com/insight-and-intelligenceand153/app-connects-rare-disease-researchers-to-data/77899637/

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Meet our Authors: Francesca Kerton

Francesca Kerton is Associate Professor of Green Chemistry at the Memorial University of Newfoundland, Canada.  Her research into green chemistry encompasses three main themes: catalysis (including organometallic chemistry), solvent replacement (including supercritical fluids) and renewable feedstocks.  Fran kindly spared a few moments to chat to Green Chemistry

Who or what initially inspired you to become a chemist?

When I was very young, like many other children, I played in the garden making mud-pies and would attempt to make perfumes using the flowers there. I always liked to get my hands dirty and was a bit of a tomboy. At the root of this, I think I really wanted to understand how things worked, what they were made from and if you could turn them into something else. So in that regard, nature was my inspiration. When I was older and began secondary school, some of our first practical classes involved separations and paper chromatography. These also included looking at isolating chlorophyll and other natural products from plants. My school had excellent chemistry teachers, who would go the extra mile to explain things and challenge the bright students. Most importantly, they made what we were learning relevant to everyday life. I have very fond memories of my GCSE and A-Level Chemistry teachers, Ms. Jones and Mr. Woodstock, and they definitely inspired me to pursue a career in chemistry.

What was the motivation behind the research described in your recent Green Chemistry article?

I have been interested in ‘green’ solvents for sometime and water, ionic liquids and carbon dioxide have all been used in my group recently. I relocated to Newfoundland in Canada from the UK in 2005. In the UK, I had been involved with the Green Chemistry Group at York and had just started to perform research using renewable feedstocks to make new materials and compounds. Historically, Newfoundland had a large fishing industry and it still has a vibrant fishing community, particularly in both catching and farming shellfish. I knew that this industry would produce a number of by-products and I was particularly interested in seeing whether we could add value to these. In particular, could chitin (the biopolymer in the shells of crustaceans) be depolymerized under green conditions and produce useful compounds? We also wanted to keep things cheap and simple, therefore, we decided to look at reactions of chitin and chitosan in water using commercially available catalysts. We found that the results with chitosan were not that different to those that had been obtained using cellulose as a feedstock, namely, we obtained levulinic acid and 5-hydroxymethylfurfural as the primary products (Green Chemistry, 2012, 14, 1480-1487).  This gives me some hope that ocean-sourced biomass can be used as a feedstock in future biorefineries alongside land-sourced materials.

What do you see as the main challenges facing research in this area?

Industrial implementation of new, green ideas is of course important for the success of this field. However, this could be helped if more industries were a little more transparent and made us aware of their real problems. I think the ACS GCI pharmaceutical roundtable has helped green chemists at universities focus their attention on real rather than imagined problems. It would be great to see this approach extended to other industries including those where perhaps the beneficial role that green chemistry could play is perhaps less obvious e.g. food industry and mining industry. Also, collaboration across the sub-disciplines is really important for the development of this field.  There are some problems here, for example, the units and language used by chemical engineers is different to that used by chemists – so we need to make an effort and be patient with each other in order to solve important problems and achieve our goals.

Where do you see the field of Green Chemistry being in 5 or 10 years time?

I am an optimist and see the field growing enormously and becoming a global endeavor. I see more collaborations across disciplines and the establishment of worldwide research networks to tackle some of the key problems of sustainability such as universal access to a clean water supply.

And finally…

If you could not be a scientist, but could be anything else, what would you be?

I love music. At high school and as an undergraduate, I sang in a band. I don’t think I would have had what it takes to do that for a living but I would have liked to be involved behind the scenes in the music industry or be a promoter of shows and concerts or an event planner.

Take a look at a couple of Fran’s recent Green Chemistry articles – free to access until the 8th August:

Hydrolysis of chitosan to yield levulinic acid and 5-hydroxymethylfurfural in water under microwave irradiation, Khaled W. Omari, Jessica E. Besaw and Francesca M. Kerton, Green Chem., 2012, 14, 1480-1487

Synthesis of Pd nanocrystals in phosphonium ionic liquids without any external reducing agents, Hassan A. Kalviri and Francesca M. Kerton, Green Chem., 2011, 13, 681-686

Keep up-to-date with the latest content in Green Chemistry by registering for our free table of contents alerts.

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Polyamide precursors from renewable 10-undecenenitrile and methyl acrylate via olefin cross-metathesis

French scientists report a ruthenium-catalysed cross-metathesis route to produce a C12 nitrile ester with high turnover number.

10-Undecylenic acid derivatives are a valuable feedstock readily available from caster oil and have been used for the industrial production of polyamide.  In this work, scientists from CBRS-University of Rennes and ARKEMA in France demonstrate that the linear C12 α,ω-amino ester, a precursor to polyamide, can be prepared viacross-metathesis of methyl acrylate with 10-undecenenitrile (which is bio-sourced) in the presence of ruthenium-alkylidene catalysts.  Subsequent C=C and nitrile reduction could then be performed to produce the C12 α,ω-amino ester.

This overall tandem procedure provides a sustainable route to linear amino esters, where a single catalyst is used from the outset to perform 3 catalytic transformations (cross-metathesis, carbon-carbon double bond hydrogenation and nitrile reduction) using bio-sourced starting materials.

This article is free to access until the 6th August 2012! Click on the link below to find out more…

Polyamide precursors from renewable 10-undecenenitrile and methyl acrylate via olefin cross-metathesis, X. Miao, C. Fischmeister, P. H. Dixneuf, C. Bruneau, J.-L. Dubois and J.-L. Couturier, Green Chem., 2012, DOI: 10.1039/C2GC35648A

You may also be interested in these articles too – free to access for 2 weeks:

Ruthenium–alkylidene catalysed cross-metathesis of fatty acid derivatives with acrylonitrile and methyl acrylate: a key step toward long-chain bifunctional and amino acid compounds, X. Miao, R. Malacea, C. Fischmeister, C. Bruneau and P. H. Dixneuf, Green Chem., 2011, 13, 2911-2919

A green route to nitrogen-containing groups: the acrylonitrile cross-metathesis and applications to plant oil derivatives, Xiaowei Miao, Pierre H. Dixneuf, Cédric Fischmeister and Christian Bruneau, Green Chem., 2011, 13, 2258-2271

Stay up-to-date with the latest news and content in Green Chemistry by registering for our free table of contents alerts.

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Organic solvent nanofiltration: an alternative method for solvent recovery from crystallisation mother liquors

UK Scientists report the feasibility of solvent recovery via solvent nanofiltration as an alternative to distillation.

Distillation has been the common technique employed for separating solvent from crystallisation mother liquors for many years.  However, although high purity solvent is generated from this process, it can be very energy-intensive and so a low energy alternative is highly sort after.  Here, Christopher Pink and colleagues from GlaxoSmithKline R&D Ltd and Imperial College London, UK, report the use of organic solvent nanofiltration (OSN) as an alternative to distillation for solvent recovery.  The team report that OSN is capable of recovering the organic solvent with a purity suitable for re-use in subsequent crystallisation processes, and energy-efficiency calculations show that OSN uses 25 times less energy per L of recovered solvent compared to distillation. 

However, the efficiency of this membrane-based solvent recovery is restricted by the solubility of the compounds within the waste stream, and can result in the recovery of less solvent for OSN.  But equivalent recovery volumes can be obtained with a combined distillation/OSN approach, still resulting in 9 times less energy consumption than when using distillation alone. 

This article is free to access until the 31st July 2012!  Click on the link below to find out more…

Organic solvent nanofiltration: a potential alternative to distillation for solvent recovery from crystallisation mother liquors, Elin M. Rundquist, Christopher J. Pink and Andrew G. Livingston, Green Chem., 2012, DOI: 10.1039/C2GC35216H

You may also be interested in these articles – free to access for 2 weeks:

Environmentally friendly route for the preparation of solvent resistant polyimide nanofiltration membranes, Iwona Soroko, Yogesh Bhole and Andrew Guy Livingston, Green Chem., 2011, 13, 162-168

Product recovery from ionic liquids by solvent-resistant nanofiltration: application to ozonation of acetals and methyl oleate, Charlie Van Doorslaer, Daan Glas, Annelies Peeters, Angels Cano Odena, Ivo Vankelecom, Koen Binnemans, Pascal Mertens and Dirk De Vos, Green Chem., 2010, 12, 1726-1733

Keep up-to-date with the latest content in Green Chemistry by registering for our free table of contents alerts!

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)