BACKGROUNDThe development and commercialisation of new chemical classes of insecticides for efficient crop protection measures against destructive invertebrate pests is of utmost importance to overcome resistance issues and to secure sustainable crop yields. Flupyradifurone introduced here is the first representative of the novel butenolide class of insecticides active against various sucking pests and showing an excellent safety profile.RESULTSThe discovery of flupyradifurone was inspired by the butenolide scaffold in naturally occurring stemofoline. Flupyradifurone acts reversibly as an agonist on insect nicotinic acetylcholine receptors but is structurally different from known agonists, as shown by chemical similarity analysis. It shows a fast action on a broad range of sucking pests, as demonstrated in laboratory bioassays, and exhibits excellent field efficacy on a number of crops with different application methods, including foliar, soil, seed treatment and drip irrigation. It is readily taken up by plants and translocated in the xylem, as demonstrated by phosphor imaging analysis. Flupyradifurone is active on resistant pests, including cotton whiteflies, and is not metabolised by recombinantly expressed CYP6CM1, a cytochrome P450 conferring metabolic resistance to neonicotinoids and pymetrozine.CONCLUSIONThe novel butenolide insecticide flupyradifurone shows unique properties and will become a new tool for integrated pest management around the globe, as demonstrated by its insecticidal, ecotoxicological and safety profile. © 2014 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Copper-catalyzed C-N-, C-O-and C-S-coupling reactions are powerful tools in organic synthesis and have been extensively reinvestigated in the past five years. The understanding of solubilizing and accelerating effects exhibited by substrates and ligands initiated novel developments originally on N-arylation of amines, amides, and nitrogen heterocycles. Nevertheless practical methods for the syntheses of aryl ethers and aryl thioethers have been established as well. A wide range of arylating reagents was explored, of which the aryl halides will be presented in this overview. Among a growing set of ligands and optimized reaction protocols, the most promising procedures are highlighted, covering the literature published through May 2003.

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The time dependence of the diffusion process at the interface between two thin films of protonated and deuterated poly(methyl methacrylate) (PMMA) is studied. By neutron reflection, we investigate both the form and the width of the interface between the two polymer layers with subnanometer resolution. At small diffusion times the movement of chain segments across the interface is followed in detail. Different characteristic time regimes for the broadening of the interface are distinguished. In addition, the form of the interfacial profile changes during the diffusion process and deviates at small diffusion times significantly from an error function profile, which would be assumed for normal Fickian diffusion. The results are discussed within the predictions of the reptation model and are compared to experiments with polystyrene films.

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