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Bis(oxazoline)-palladium(II) catalyzed carbonylation of homopropargyl alcohols afforded acyclic methoxyacrylate 2 and 6-membered lactone 3 a-k in good combined yield. In the case of propargyl alcohols, 5-membered lactones 3 p, 3 q, 16 were obtained in moderate yields. The one-pot synthesis of kawa lactones 3 a, 3 r, 3 s and formal synthesis of dihydroxycystothiazole A and dihydroxycystothiazole C are presented. To elucidate the stereochemistry of (+)-annularin G and (-)-annularin H, the first asymmetric syntheses of these natural products were achieved.

The scope of the novel ruthenium-catalyzed tandem cross-metathesis/intramolecular-hydroarylation sequence is described. This methodology offers a practical and efficient synthesis of structurally diverse and complex tetrahydrocarbazoles in good to excellent yields (up to 98 %). Moreover, preliminary efforts towards the development of an enantioselective version of the current process by sequential catalysis with ruthenium complex and chiral amine are presented, with high yields and enantioselectivities (up to 88 % yield and 91 % ee).

Ideal for scaffold diversity synthesis: The first organocatalytic direct vinylogous Michael addition of N-Boc [alpha],[beta]-unsaturated [gamma]-butyrolactam to [alpha],[beta]-unsaturated aldehydes has been developed. The products with multiple orthogonal sets of functionalities were transformed into diverse enantioenriched natural-product-like or drug-like molecules with fused bi-, tri-, or polycyclic scaffolds (see scheme), which might have potential for biologically related studies.

Galvanising chemistry! Galvanic replacement reactions have a very long history. However, its powerful capabilities have not been fully exploited for nanomaterial syntheses yet. Now, using very cheap, commercially available Al/Mg powders as sacrificial materials, various metals (most transition and rare earth) with a large variety of novel nanostructures can be obtained easily in a very large scale (see picture).

A powerful chiral building block: A concise enantioselective synthesis of the diazatricyclic core of sarain A has been accomplished. The novel strategy is relies upon the versatile chiral building block (R)-1 (see scheme), and features a tandem Horner-Wadsworth-Emmons-aza-Michael reaction, an intramolecular Michael reaction, and the diastereoconvergent formation of the third ring. Diazatricyclic core 2 possesses all of the necessary functionality for further elaboration into sarain A.

Unexpected Heck: During efforts toward the synthesis of FR900482, an unexpected domino-Heck product was isolated (see scheme). Although this pathway was ultimately not productive for the aforementioned natural product synthesis, efforts were made to extend the methodology to the synthesis of amurensinine. To our knowledge this domino reaction was the first such tandem Heck-alkylation pathway in the presence of a geometrically favorable [beta]-hydrogen elimination.

Kinetic isotope effects are exquisitely sensitive probes of transition structure. As such, kinetic isotope effects offer a uniquely useful probe for the symmetry-breaking process that is inherent to stereoselective reactions. In this Concept article, we explore the role of steric and electronic effects in stereocontrol, and we relate these concepts to recent studies carried out in our laboratory. We also explore the way in which kinetic isotope effects serve as useful points of contact with computational models of transition structures. Finally, we discuss future opportunities for kinetic isotope effects to play a role in asymmetric catalyst development.

Functionalised MCM-41 mesoporous silica nanoparticles were used as carriers of GdIII complexes for the development of nanosized magnetic resonance imaging contrast agents. Three GdIII complexes based on the 1,4,7,10-tetraazacyclododecane scaffold (DOTA; monoamide-, DOTA- and DO3A-like complexes) with distinct structural and magnetic properties were anchored on the silica nanoparticles functionalised with NH2 groups. The interaction between GdIII chelates and surface functional groups markedly influenced the relaxometric properties of the hybrid materials, and were deeply modified passing from ionic [bond]NH3+ to neutral amides. A complete study of the structural, textural and surface properties together with a full 1H relaxometric characterisation of these hybrid materials before and after surface modification was carried out. Particularly for the anionic complex 2 attached to MCM-41, an impressive increase in relaxivity (r1p) was observed (from 20.3 to 37.8 mM-1 s-1, 86.2 % enhancement at 20 MHz and 310 K), mainly due to a threefold faster water exchange rate after acetylation of the surface [bond]NH3+ ions. This high r1p value, coupled with the large molar amount of grafted 2 onto the silica nanoparticles gives rise to a value of relaxivity per particle of 29 500 mM-1 s-1, which possibly allows it to be used in molecular imaging procedures. Smaller changes were observed for the hybrid materials based on neutral 1 and 3 complexes. In fact, whereas 1 shows a weak interaction with the surface and acetylation induced only some decrease of the local rotation, complex 3 appears to be involved in a strong interaction with surface silanols. This results in the displacement of a coordinated water molecule and in a decrease of the accessibility of the solvent to the metal centre, which is unaffected by the modification of ammonium ions to neutral amides.

We have realized for the first time a series of truly water-soluble and tightly coupled porphyrin/C60 electron-donor-acceptor conjugates in which the charge separation and charge recombination dynamics are controlled by modifying the nature of the dendrimer and/or the choice of the central metal atom.

I review a concept that models heterogeneous catalysis based on a surface-science approach. It is shown that models catching part of the complexity of the real system, which is connected with the finite size of active components and the flexibility of the arrangement of atoms in the active component, play an important part in determining the activity and selectivity of the system. I have chosen several examples from our own laboratory to elaborate the details and will put those into perspective with respect to the literature. I will show that Pd nanoparticles in hydrogenation incorporate hydrogen, which turns out to be crucial for the actual hydrogenation step. Another example correlates the structure of vanadia monolayer catalysts with its reactivity in methanol oxidation. With a third example we address the question of charge on Au nanoparticles when anchored to an oxide surface, a problem heavily discussed in the literature. Further examples refer to ultrathin oxide film catalysts in which the oxide metal interface controls either the charge state of Au particles grown on the film, and, in a last example, the oxide film itself exhibits remarkable CO-oxidation activity, which can be traced to a reactive intermediate structure of the ultrathin film.