Chemistry and Brexit

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The European Chemical Society (EuChemS)

The European Chemical Society (EuChemS) coordinates the work of almost all the European Chemical Societies. As an organization, it provides an independent and authoritative voice on all matters relating to chemistry, and try to place chemistry at the heart of policy in Europe. Furthermore, EuChemS seeks to develop its members through various activities, workshops and awards. Particularly, EuChemS has fostered growth in its young members through the European Young Chemists′ Network. Beyond Europe, EuChemS has collaborated with various organizations in bringing chemistry out of the lab and into society in building a sustainable future for everyone.PostprintPeer reviewe

On the catalytic activity of [RuH2(PPh3)3(CO)] (PPh3 = triphenylphosphine) in ruthenium-catalysed generation of hydrogen from alcohol : a combined experimental and DFT study

We wish to thank Lucite International for a studentship (P.L.) and EaStCHEM for support and access to the EaStCHEM Research Facility. We also thank Dr. H. Früchtl for technical support. N.S. thanks the Univ. Grenoble Alpes, the CNRS and the ICMG FR 2607 for financial support. The Pcecic and Froggy platforms of the CIMENT infrastructure are also acknowledged (project “liqsim”).Using Density Functional Theory calculations (at the B97-D2//BP86 level) and measurements of kinetic isotope effects, we explored the mechanism of [RuH2(PPh3)3(CO)] ( 22 ) in catalytic acceptor-less dehydrogenation of methanol to formaldehyde. 22 is found to exhibit a similar activity as the previously studied [RuH2(H2)(PPh3)3] ( 1b ) complex. On the computed pathway, η2 → η1 slippage of Ru-bound formaldehyde prior to decoordination is indicated to be rate-limiting, consistent with the low kH/kD KIE of 1.3 measured for this reaction. We also explored computationally the possibility of achieving complete dehydrogenation of methanol (into CO2 and H2), through subsequent decarbonylation of formaldehyde and water-gas shift reaction of the resulting carbonyl complex. Complete pathways of this kind are traced for 22 and for [RuH2(PPh3)2(CO)2]. An alternative mechanism, involving a gem-diol intermediate (obtained upon attack of OH- to coordinated formaldehyde), has also been investigated. All these pathways turned out to be unfavourable kinetically, in keeping with the lack of CO2 evolution experimentally observed in this system. Our calculations show that the reactions are hampered by the low electrophilicities of the CO and HCHO ligands, making OH- uptake unfavourable. Consequently, the subsequent intermediates are too high-lying on the reaction profiles, thus leading to high kinetic barriers and preventing full dehydrogenation of methanol to occur by this kind of mechanism.Publisher PDFPeer reviewe

Determination of the Baryon Density from Large Scale Galaxy Redshift Surveys

We estimate the degree to which the baryon density, $\Omega_{b}$, can be determined from the galaxy power spectrum measured from large scale galaxy redshift surveys, and in particular, the Sloan Digital Sky Survey. A high baryon density will cause wiggles to appear in the power spectrum, which should be observable at the current epoch. We assume linear theory on scales $\geq 20h^{-1}Mpc$ and do not include the effects of redshift distortions, evolution, or biasing. With an optimum estimate of $P(k)$ to $k\sim 2\pi/(20 h^{-1} Mpc)$, the $1 \sigma$ uncertainties in $\Omega_{b}$ are roughly 0.07 and 0.016 in flat and open ($\Omega_{0}=0.3$) cosmological models, respectively. This result suggests that it should be possible to test for consistency with big bang nucleosynthesis estimates of $\Omega_{b}$ if we live in an open universe.Comment: 23 Pages, 10 Postscript figure

Chemical weapons : what is the purpose? The Hague ethical guidelines

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Magic of alpha : the chemistry of a remarkable bidentate phosphine, 1,2-bis(di-tert-butylphosphinomethyl)benzene

We thank the Fonds der Chemischen Industrie for a Kekulé Fellowship for a studentship and the Deutsche Forschungsgemeinschaft (DFG, project number 424535516) for support (J.V.). We are also very grateful to Lucite International for funding the work in St Andrews that is contained in this review.The bidentate phosphine ligand 1,2-bis(di-tert-butylphosphinomethyl)benzene (1,2-DTBPMB) has been reported over the years as being one of, if not the, best ligands for achieving the alkoxycarbonylation of various unsaturated compounds. Bonded to palladium, the ligand provides the basis for the first step in the commercial (Alpha) production of methyl methacrylate as well as very high selectivity to linear esters and acids from terminal or internal double bonds. The present review is an overview covering the literature dealing with the 1,2-DTBPMB ligand: from its first reference, its catalysis, including the alkoxycarbonylation reaction and its mechanism, its isomerization abilities including the highly selective isomerizing methoxycarbonylation, other reactions such as cross-coupling, recycling approaches, and the development of improved, modified ligands, in which some tert-butyl ligands are replaced by 2-pyridyl moieties and which show exceptional rates for carbonylation reactions at low temperatures.PostprintPeer reviewe

Employment and Careers of European Chemists (ESEC2)

Employment conditions and career opportunities are in the focus of the new Employment Survey for European Chemists (ESEC2). Conditions and opportunities are individually analysed for all countries with a statistically significant number of responses. The results provide important clues for careers in these countries and in Europe as a whole. The importance of employer sectors varies very much between European countries. A chapter of this report is devoted to career planning of students and new graduates. This is the first general evaluation of the survey. It provides many details about the chemistry workforce in Europe and its development.Publisher PDFPeer reviewe

Employment and Careers of European Chemists (ESEC2)

Employment conditions and career opportunities are in the focus of the new Employment Survey for European Chemists (ESEC2). Conditions and opportunities are individually analysed for all countries with a statistically significant number of responses. The results provide important clues for careers in these countries and in Europe as a whole. The importance of employer sectors varies very much between European countries. A chapter of this report is devoted to career planning of students and new graduates. This is the first general evaluation of the survey. It provides many details about the chemistry workforce in Europe and its development.Publisher PDFPeer reviewe

Lake-size dependency of wind shear and convection as controls on gas exchange

High-frequency physical observations from 40 temperate lakes were used to examine the relative contributions of wind shear (u*) and convection (w*) to turbulence in the surface mixed layer. Seasonal patterns of u* and w* were dissimilar; u* was often highest in the spring, while w * increased throughout the summer to a maximum in early fall. Convection was a larger mixed-layer turbulence source than wind shear (u */w*-1 for lakes* and w* differ in temporal pattern and magnitude across lakes, both convection and wind shear should be considered in future formulations of lake-air gas exchange, especially for small lakes. © 2012 by the American Geophysical Union.Jordan S. Read, David P. Hamilton, Ankur R. Desai, Kevin C. Rose, Sally MacIntyre, John D. Lenters, Robyn L. Smyth, Paul C. Hanson, Jonathan J. Cole, Peter A. Staehr, James A. Rusak, Donald C. Pierson, Justin D. Brookes, Alo Laas, and Chin H. W

Synthesis of pharmaceutical drugs from cardanol derived from cashew nut shell liquid

Authors thank the EPSRC for the critical mass grant ‘Clean Catalysis for Sustainable Development’ (EP/J018139/1), Sasol Technology, UK for a case studentship (Y. S.).Cardanol from cashew nut shell liquid extracted from cashew nut shells was successfully converted into various useful pharmaceutical drugs, such as norfenefrine, rac-phenylephrine, etilefrine and fenoprofene. 3-Vinylphenol, the key intermediate for the synthesis of these drugs, was synthesised from cardanol by ethenolysis to 3-non-8-enylphenol followed by isomerising ethenolysis. The metathesis reaction worked very well using DCM, but the greener solvent, 2-methyl tetrahydrofuran, also gave very similar results. Hydroxyamination of 3-vinylphenol with an iron porphyrin catalyst afforded norfenefrine in over 70% yield. Methylation and ethylation of norfenefrine afforded rac-phenylephrine and etilefrine respectively. A sequence of C–O coupling, isomerising metathesis and selective methoxycarbonylation afforded fenoprofene in good yield. A comparison of the routes described in this paper with some standard literature syntheses of 3-vinylphenol and of the drug molecules shows significant environmental advantages in terms of precursors, yields, number of steps, conditions and the use of catalysts. The Atom Economy of our processes is generally similar or significantly superior to those of the literature processes mainly because the side products produced during synthesis of 3-vinylphenol (1-octeme, 1,4-cyclohexadiene and propene) are easily separable and of commercial value, especially as they are bio-derived. The E Factor for the production of 2-vinylphenol by our process is also very low compared with those of previously reported syntheses.Publisher PDFPeer reviewe