Photocured thiol-ene based optical fluorescence sensor for determination of gold(III)

This study describes the preparation and the characterization of a new thiol-ene based polymeric fluorescence sensor by photo initiated polymerization of trimethylolpropane tris(3-mercaptopropionate), 2-hydroxyethylacrylate, and 2,4,6-triallyloxy-1,3,5-triazine which are used as monomers and also a photo initiator (2,2-dimethoxy-2-phenylacetophenone) for its usage as optical sensor for gold ions. The thiol-ene based polymeric membrane sensor was characterized by using attenuated total reflectance-fourier transform infrared spectroscopy (ATR-FTIR) and scanning electron microscopy (SEM). The response characteristics of the sensors including dynamic range, pH effect, response time, and the effect of foreign ions were investigated. Fluorescence spectra showed that the excitation/emission maxima of the membrane were at 379/425 nm, respectively     

Enantioselective Synthesis of Isoxazolines Enabled by Palladium‐Catalyzed Carboetherification of Alkenyl Oximes

Reported here is a highly efficient Pd/Xiang‐Phos catalyzed enantioselective carboetherification of alkenyl oximes with either aryl or alkenyl halides, delivering various chiral 3,5‐disubstituted and 3,5,5‐trisubstituted isoxazolines in good yields with up to 97 % ee. The sterically bulky and electron‐rich (S,Rs)‐ NMe‐X2 ligand is responsible for the excellent reactivities and enantioselectivities. The salient features of this transformation include mild reaction conditions, general substrate scope, good functional‐group tolerance, good yields, high enantioselectivities, easy scale‐up, and application in the late‐stage modification of bioactive compounds. The obtained products can be readily transformed into useful chiral 1,3‐aminoalcohols.     

Synthesis,spectroscopic properties,crystal structures,antioxidant activities and enzyme inhibition determination of Co(II) and Fe(II) complexes of Schiff base

Research on Chemical Intermediates - Considering the importance of metal complexes in the development of medical science, two different Schiff base Fe(II) and Co(II) metal complex compounds were...     

Dehydroxylation of high-energy ball-milled diasporic bauxite

The review consists of four parts. Part I is about the thermal transformation in clay minerals under firing and about the properties of fired clay. The transformations in the clay are expressed quantitatively with the extent of conversion, α, which is the function of two parameters of firing process, time t and temperature T: α?=?f(t, T). Part II is about the estimation of firing temperature after the analysis of the products of firing clays. All the estimations are speculative, without mathematical equations. It is impossible to derive the value of only one variable T from α?=?f(t,T), the function of two variables. Part III is about the long-term inverse transformation in fired ceramic paste under ambient conditions. The mass gain as a function of time is used for the evaluation of the time elapsed from the ancient firing, t. Part IV is about the visualization of the extent of conversion of the clay in the paste after all direct and reverse reactions, i.e., α.