This work presents a new synthesis of nano-sized lithium niobate particles by a low temperature three steps procedure. The complete protocol implies a LiH induced reduction of NbCl₅ followed by in situ spontaneous oxidation into low valence niobium nano-oxides. These niobium oxides are exposed to air atmosphere leadingto pure Nb₂O₅ formation. Finally, the stable Nb₂O₅ is converted into lithium niobate LiNbO₃ nanoparticles duringthe controlled hydrolysis of the LiH excess. The nano-sized lithium niobate particles as well as their formation processes were characterized using X-ray photoelectron spectroscopy.

During the past twenty years, cyclodextrins (CDs) have proven to be very effective in aqueous biphasic catalysis. They could act as molecular receptors for numerous organic substrates and favour their conversion at the aqueous/organic interface. Recently, new applications have been found for CDs in aqueous catalysis. CDs can now be defined as polyfunctional entities between the substrate-containing phase and the catalyst-containing phase. In this paper, we highlight the latest breakthroughs in the use of CDs in catalysis through several examples from the literature.

At the boundary between mechanochemistry, supramolecular chemistry and catalysis, the present study explores the role of cyclodextrins (CDs) and other saccharide additives in the mechanosynthesis of gold nanoparticles (AuNPs) and their use as catalysts in the reduction of substituted nitrobenzene derivatives into their corresponding aniline products. CDs not only allow for the stabilization of the AuNPs but also help diffuse a substrate within a solid mixture via supramolecular means, and orient the chemical reaction to the selective formation of aniline derivatives. Parameters influencing both the formation of AuNPs and the synthesis of aniline derivatives have been investigated. We show that the catalytic performance strongly depends upon the nature of the saccharide additive, the nature and location of the substituent on the benzene, and the ball-milling conditions. Water also plays a key role in both the reduction mechanism of the nitro groups and the supramolecular interactions with the substrate. Very interestingly, the amount of reductive agent (NaBH₄) was drastically reduced compared to reductions performed in solution. Additionally, the catalytic system could be recycled over three consecutive runs without significant loss in activity, thus highlighting the efficacy of the combination of mechanochemistry, supramolecular chemistry, and catalysis.

β-Cyclodextrin series and N,N′-dimethylurea formed low melting mixtures able to immobilize organometallic species based on sulfonated phosphanes. Hydroformylation and Tsuji–Trost reactions were efficiently performed in these new solvents which led to new recyclable catalytic systems.