Recent advance in high-pressure solid-state metathesis reactions

High-pressure solid-state metathesis(HPSSM)reaction is an effective route to novel metal nitrides.A recent advance in HPSSM reactions is presented for a number of examples,including 3d transition metal nitrides(ε-Fe_(3)N,ε-Fe_(3-x)Co_(x)N,CrN,and Co_(4)N_(x)),4d transition metal nitrides(MoNx),and 5d transition metal nitrides(Re_(3)N,WN_(x)).Thermodynamic investigations based on density functional theory(DFT)calculations on several typical HPSSM reactions between metal oxides and boron nitride indicate that the pressure could reduce the reaction enthalpy △H.High-pressure confining environment thermodynamically favors an ion-exchange process between metal atom and boron atom,and successfully results in the formation of well-crystalized metal nitrides with potential applications.

A New Approach to Inducing Silicon Tethered Ring-closing Metathesis Reactions

Ring-closing metathesis reactions involving diallyldiphenylsilane and diallyloxydiphenylsilane were successfully performed by using only 0 01 mol or even less of Grubbs' catalyst 1. The effects of reaction parameters, such as solvents, temperature and concentration of the catalyst are discussed.

Nanoporous AlN particle production from a solid-state metathesis reaction

This paper reports that nanoporous AlN particles are synthesized from solid-state metathesis reactions using AlCl3 and Mg3N2 as reactants.The samples are characterized by x-ray diffraction （XRD）,transmission electron microscopy （TEM）,selected area electron diffraction, high-resolution transmission electron microscopy （HRTEM）,ultraviolet-visible （UV-vis） absorption spectroscopy and Raman spectroscopy.The results show that samples with walls 10 nm in thickness and pores between 10 nm and 100 nm in diameter were produced successfully from these reactions,and their band gap and vibration modes agree with those of AlN bulk crystal.

Applications of Cyclometalation Five-Membered Ring Products and Intermediates as Catalytic Agents

The five-membered ring products and intermediates of cyclometalation reactions are very easily synthesized via donation from a hetero atom to a metal atom, which leads to the very high functionality of the product. This functionality is caused by the donation of the hetero atom and various types of metal atoms, halogen atom and other ligands such as alkanes, alkenes, alkynes, Cp, Cp*, aryl groups and heterocyclic compounds. These products have three types of catalytic applications: cyclometalation five-membered ring products as catalysts, cyclometalation five-membered ring intermediates as catalyst agents and cyclometalation five-membered ring intermediates with unconventional substrates and as catalyst actions. Because of the high functionality of these products, the applications of them have been increasing not only as the metathesis in the first and second generations of Hoveyda-Grubbs catalysts but also as in chiral reactions, cross-coupling reactions and polymerization reactions. The above cyclometalation products have been utilized for the production in many industrial fields such as pharmaceuticals, OLEDs, carbon dioxide utilizations, dye-sensitizer solar cells and sensors. We expect that these products would be used for the development of further new industrial products.

The dynamic covalent reaction based on diselenide-containing crown ether irradiated by visible light

A novel diselenide-containing crown ether(BC7Se_(2))was fabricated,which can polymerize to form cyclic oligomers through intermolecular dynamic covalent reaction by irradiation of visible light.The size and distribution of oligomers are related to the monomer concentration.The decomposition reaction of oligomers is controlled by topology and solvents.Furthermore,potassium cation can inhibit the polymerization of BC7Se_(2)and accelerate the decomposition of oligomers.

Synthesis and Characterization of Novel Lanthanocene Complexes with Dichalcogenolate o-Carboranyl Ligands

Reactions of [Cp2Ln(μ-Cl)]2 (Cp= η5-C5H5, Ln = Nd, Yb, Dy, Gd, Er) with an equivalent of [(THF)3LiE2C2Bi0H10Li. (THF)]2 (E= S, Se) in THF afforded the dinuclear sandwich complexes of formula [CP2LnE2C2B10H10]2[LI(THF)4]2[E = S, Ln=Nd (1a), Yb (2a), Dy (3a), Gd (4a), Er (5a); E=Se, Ln=Nd (1b), Yb (2b), Dy (3b), Gd (4b), Er (5b)]. The molecular structures of complexes la, 2a and 2b were determined by the single crystal X-ray structure analyses. Two lanthanide atoms are connected by a pair chalcogen (η1, η2-E2C2B10H10) bridging ligands and the central Ln2E2 four membered ring is not planar.