A density functional theory study is performed on the reactions of α,β‐unsaturated oxime pivalates and alkenes through Cp*RhIII‐catalyzed (Cp* = pentamethylcyclopentadienyl) C–H activation. The catalytic cycle involves reversible metalation–deprotonation, migratory alkene insertion, pivaloyl transfer to the Rh center, and reductive elimination, among other steps. The results show that the migratory alkene insertion is rate‐determining and that the reductive elimination to form the product‐ligated species makes the reaction irreversible (exergonic by 60 kcal/mol). If the electron‐donating ability of the substituents on the cyclopentadienyl (Cp) ligand is increased or an electron‐withdrawing group is introduced into the terminus of the alkene, the apparent activation energy of the reaction increases. In contrast, if a stronger electron‐donating group is introduced at the 2‐position of the α,β‐unsaturated oxime pivalate, the apparent activation energy of the reaction decreases greatly, and the reaction can be performed at room temperature. On the other hand, for phenyl groups at the 2‐position, the introduction of a more electron‐deficient p‐CF3‐phenyl group increases the apparent activation energy. Finally, the diastereoselectivity of the reaction with cyclohexylethylene as the substrate is attributable to a clash between the cyclohexyl group and the α,β‐unsaturated oxime pivalate.

Meeting Summary The 20th annual symposium of the International Isotope Society's United Kingdom Group took place at the Wellcome Genome Campus, Hinxton, Cambridge, UK on Tuesday 18 October 2011. The meeting was attended by around 70 delegates from academia and industry, the life sciences, chemical, radiochemical and scientific instrument suppliers. Delegates were welcomed by Dr Ken Lawrie (GlaxoSmithKline, UK, chair of the IIS UK group). The subsequent scientific programme consisted of oral and poster presentations on isotopic chemistry and applications of labelled compounds or of chemistry with potential implications for isotopic synthesis. Both short‐lived and long‐lived isotopes were represented, as were stable isotopes. The symposium programme was divided into a morning session chaired by Prof. Chris Willis (University of Bristol, UK) and afternoon sessions chaired by Mr Mike Chappelle (Quotient Biosciences, UK) and by Dr Nick Bushby (AstraZeneca, UK). The UK meeting concluded with remarks from Dr Ken Lawrie (GlaxoSmithKline, Stevenage, UK).

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