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HYPOTHESIS: In this original work, we aim to control both the surface wetting and fluorescence properties of extremely ordered and porous conducting polymer nanotubes prepared by soft template electropolymerization and post-grafting. For reaching this aim, various substituents of different hydrophobicity and fluorescence were post-grafted and the post-grafting yields were evaluated by surface analyses. We show that the used polymer is already fluorescent before post-grafting while the post-grafting yield and as a consequence the surface hydrophobicity highly depend on the substituent. EXPERIMENTS: Here, we have chosen to chemically grafting various fluorinated and aromatic substituents using a post-grafting in order to keep the same surface topography. Flat conducting polymer surfaces with similar properties have been also prepared for determining the surface energy with the Owens-Wendt equation and estimating the post-grafting yield by X-ray Photoemission Spectroscopy (XPS) and Time of Flight Secondary Emission Spectrometry (ToF-SIMS). For example, using fluorinated chains of various length (C4F9, C6F13 and C8F17), it is demonstrated that the surface hydrophobicity and oleophobicity do not increase with the fluorinated chain length due to the different post-grafting yields and because of the presence of nanoroughness after post-grafting. FINDINGS: These surfaces have high apparent water contact angle up to 130.5° but also strong water adhesion, comparable to rose petal effect even if there are no nanotubes on petal surface. XPS and ToF-SIMS analyses provided a detailed characterisation of the surface chemistry with a qualitative classification of the grafted surfaces (F6 > F4 > F8). SEM analysis shows that grafting does not alter the surface morphology. Finally, fluorescence analyses show that the polymer surfaces before post-treatment are already nicely fluorescent. Although the main goal of this paper was and is to understand the role of surface chemistry in tailoring the wetting properties of these surfaces rather than provide specific application examples, we believe that the obtained results can help the development of specific nanostructured materials for potential applications in liquid transport, or in stimuli responsive antimicrobial surfaces.

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The activation of ruthenium-indenylidene complexes containing two unsymmetrical unsaturated N-heterocyclic carbenes (u2-NHCs) by a transmetalation process is reported. The use of copper(i) or gold(i) chlorides promotes the rapid trapping of one NHC ligand, which releases the catalytically active Ru-species. Impressive initiation rates with full-conversions are observed within one minute. This practical protocol demonstrates excellent catalytic performances in various ring-closing metathesis (RCM) and self-metathesis (SM) reactions.

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The preparation, characterisation and application of two pyridine-modified chitosan derivatives (C1 and C2) containing Cu(OAc)2 adsorbed as catalysts for the conversion of benzaldehyde into 2-nitro-1-phenylethanol are described. Quantitative solid-state 13C multiple-contact cross-polarization, magic-angle-spinning, nuclear magnetic resonance (MC-CP MAS NMR) measurements confirmed the successful grafting of 2-pyridinecarboxaldehyde and 6-methylpyridine-2-carboxaldehyde to the chitosan backbone and indicated that 47(±2)% of the NH2 groups were grafted for both C1 and C2. The use of C1-Cu(OAc)2 as a catalyst in the nitroaldol reaction led to 96(±1)% conversion and 19(±4)% enantiomeric excess (ee), while the use of C2-Cu(OAc)2 as a catalyst also promoted the nitroaldol reaction, affording almost quantitatively the expected 2-nitro-1-phenylethanol (98(±1)%) with 14.5(±1.5)% ee.