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Schaffer C.,Bielefeld University | Todea A.M.,Bielefeld University | Gouzerh P.,CNRS Paris Institute of Molecular Chemistry | Muller A.,Bielefeld University
Chemical Communications | Year: 2012

The addition of dinuclear {Mo 2} units to a dynamic library containing molybdates results in the spontaneous self-assembly of a giant spherical metal-oxide species of the type {(Mo)Mo 5} 12{Mo 2} 30 while the required pentagonal {(Mo)Mo 5} building blocks are "immediately" formed.

Derat E.,CNRS Paris Institute of Molecular Chemistry | Maestri G.,CNRS Natural Product Chemistry Institute
Wiley Interdisciplinary Reviews: Computational Molecular Science | Year: 2013

Palladium catalyzed cross-coupling reactions are one of the most widely used class of transformation as shown by the Nobel prize awarded in 2010 to Heck, Negishi, and Suzuki. Computational chemistry has a long-standing partnership with organometallics catalysis, especially with palladium. But even in a largely explored field, novelties can emerge from interplay between experiments and theory. Recent advances grounded on computational chemistry have shown that cooperative effect can explain reactivities; that despite the large number of well-known Pd(0)/Pd(II) catalytic cycle, Pd(IV) is also a realistic intermediate in some cases; that noncovalent interactions can regulate selectivities. So, despite its wide use and recognition, palladium complexes are still full of surprises! © 2013 John Wiley & Sons, Ltd.

Muller A.,Bielefeld University | Gouzerh P.,CNRS Paris Institute of Molecular Chemistry
Chemical Society Reviews | Year: 2012

Following Nature's lessons, today chemists can cross the boundary of the small molecule world to construct multifunctional and highly complex molecular nano-objects up to protein size and even cell-like nanosystems showing responsive sensing. Impressive examples emerge from studies of the solutions of some oxoanions of the early transition metals especially under reducing conditions which enable the controlled linking of metal-oxide building blocks. The latter are available from constitutional dynamic libraries, thus providing the option to generate multifunctional unique nanoscale molecular systems with exquisite architectures, which even opens the way towards adaptive and evolutive (Darwinian) chemistry. The present review presents the first comprehensive report of current knowledge (including synthesis aspects not discussed before) regarding the related giant metal-oxide clusters mainly of the type {Mo 57M′6} (M′ = FeIII, VIV) (torus structure), {M72M′30} (M = Mo, M′ = VIV, CrIII, FeIII, MoV), {M 72Mo60} (M = Mo, W) (Keplerates), {Mo154}, {Mo176}, {Mo248} ("big wheels"), and {Mo 368} ("blue lemon") - all having the important transferable pentagonal {(M)M5} groups in common. These discoveries expanded the frontiers of inorganic chemistry to the mesoscopic world, while there is probably no collection of discrete inorganic compounds which offers such a versatile chemistry and the option to study new phenomena of interdisciplinary interest. The variety of different properties of the sphere- and wheel-type metal-oxide-based clusters can directly be related to their unique architectures: The spherical Keplerate-type capsules having 20 crown-ether-type pores and tunable internal functionalities allow the investigation of confined matter as well as that of sphere-surface-supramolecular and encapsulation chemistry - including related new aspects of the biologically important hydrophobic effects - but also of nanoscale ion transport and separation. The wheel-type molybdenum-oxide clusters exhibiting complex landscapes do not only have well-defined reaction sites but also show unprecedented adaptability regarding the integration of various kinds of matter. Applications in different fields, e.g. in materials science and catalysis including those in small spaces, investigated by several groups, are discussed while possible directions for future work are outlined. © The Royal Society of Chemistry 2012.

Queffelec C.,French National Center for Scientific Research | Petit M.,French National Center for Scientific Research | Petit M.,CNRS Paris Institute of Molecular Chemistry | Janvier P.,French National Center for Scientific Research | And 2 more authors.
Chemical Reviews | Year: 2012

The basic work of researchers on methods for surface modification including metals and metal oxide coatings, and modification of metal nanoparticles are reviewed. The Michaelis-Arbuzov reaction, also known as the Arbuzov reaction, is one of the most versatile reactions for the formation of P-C bonds. The reaction consists of a triester phosphite with an alkyl halide, resulting in the conversion of P(III) to a pentavalent phosphorus species. Hirao et al. reported the first palladium catalyzed cross-coupling of alkyl halides with dialkyl phosphite. Another attractive route to organophosphonates reported by Tanaka and co-researchers consists of the addition of HPO3R2 to alkenes, and terminal alkynes using either palladium or rhodium-based catalysts. This atom-economic process was found to be versatile, efficient, and clean. Finally, while the gold standard for grafting photoactive or electroactive molecules on semiconductors was the use of CO2H anchors, there is now a rapidly growing interest in using PO3H2 functions.

Denes F.,University of Nantes | Perez-Luna A.,CNRS Paris Institute of Molecular Chemistry | Chemla F.,CNRS Paris Institute of Molecular Chemistry
Chemical Reviews | Year: 2010

A study was conducted to demonstrate the addition of metal enolate derivatives to unactivated carbon-carbon multiple bonds. The study focused on the carbometalation of alkenes, alkynes, arenes, and related unsaturated systems involving stabilized anions, such as enolates, malonates, and related stabilized nucleophiles. The investigations focused mainly on the substrates where the unsaturation partner was not activated by an electron-withdrawing group. It was demonstrated that nucleophilic addition onto unactivated C-C multiple bonds required the activation through complexation with a metal salt. The reaction was conducted in intramolecular or intermolecular manner yielding building blocks with high regio- or diastereoselectivity. It was also observed that complexation with palladium(II) salts activated alkenes efficiently toward additions of nucleophiles, including stabilized metal enolates and silyl enol ethers.

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