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A method to prepare synthetically important 3,5-disubstituted phenol derivatives that relies on the sequential gold(I)-catalyzed dehydrogenative cycloisomerization of 1,4-enyne esters in the presence of 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) or N-fluorobenzenesulfonimide (NFSI) is described. The synthetic versatility of the methodology was exemplified by a gram-scale reaction of one example, the ease to realize subsequent functional transformations of an adduct, and the application of the method to the synthesis of the bioactive molecule LUF5771.\ud \ud

An efficient and expedient approach for the synthesis of unsymmetrical 3,3′-Bis-indolylmethanes via silica gel-mediated Friedel-Crafts alkylation of 3-indolylmethanols with diverse indoles is described. The synthetic utility of this transformation was demonstrated by reusing silica gel up to 10 times without apparent loss of reactivity .

Nanosized particles of strontium bismuth vanadate SrBi3VO8 were prepared via the Pechini method on the base of citrate-complexation route. The samples were characterized using X-ray powder diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectra (EDX), X-ray photoelectron spectroscopic (XPS), and UV–vis absorption spectrum. This bismuth-containing vanadate presents an efficient absorption in the UV–visible light wavelength region with a narrow band-gap energy of 2.36 eV and an indirect allowed electronic transition. It is well-known that hybridization of the 6s and 6p orbitals of Bi3+ could result in lone electron pair and yield some very interesting properties. The photocatalytic activities of SrBi3VO8 nanoparticles were evaluated by the photodegradation of methylene blue (MB) under visible light irradiation in air atmosphere. These results indicate that SrBi3VO8 could be a potential photocatalyst driven by visible light. To understand the charge generation and separation process, the luminescence as well as the decay lifetimes was investigated in the same samples for photocatalysis.

A visible-light-driven photocatalyst based on the well-known cathode material of NASICON-type Li2Ni2(MoO4)3 was prepared by a modified Pechini method. The sample was characterized by X-ray diffraction, scanning electron microscope, transmission electron microscopy, and UV-vis absorption spectrum. The average size of Li2Ni2(MoO4)3 particle is below 50 nm. NASICON nanoparticles Li2Ni2(MoO4)3 has an efficient absorption in the UV-visible light wavelength region with a direct allowed electronic transition of 2.07 eV. The photocatalytic properties of Li2Ni2(MoO4)3 were evaluated by the photodegradation of methylene blue (MB). Li2Ni2(MoO4)3 has an efficient photocatalytic activity and could be a potential photocatalyst driven by visible-light. The photocatalytic activity was discussed on the optical absorption and special hexagonal tunnel structure connected by optical active centers of MoO4 and NiO6 and its good conductivity.

New potassium gadolinium phosphate [K 3 Gd 5 (PO 4 ) 6 ] doped with Eu 3+ , Ce 3+ , Tb 3+ and co-doped with Ce 3+ and Tb 3+ phosphors were prepared by high temperature solid state synthesis. Phase purity of the powders was checked by X-ray powder diffraction. Luminescence and excitation spectra of samples were reported. In particular, the interaction mechanism between Eu 3+ ions was investigated in terms of the Inokuti–Hirayama model; it was found that the interactions between Eu 3+ can be assigned to dipole–dipole interaction. K 3 Gd 5 (PO 4 ) 6 :Eu 3+ could act as a candidate for solid state lighting due to its strong absorption band in the near-UV region (350–400 nm). The energy transfer from Ce 3+ to Tb 3+ was confirmed and the mechanism was studied using Dexter's theory; it is concluded that electric dipole–dipole interaction predominates in the energy transfer process from Ce 3+ to Tb 3+ in the K 3 Gd 5 (PO 4 ) 6 host. The energy transfer efficiency and critical distance were also investigated.