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A novel chelating resin, polyacrylonitrile-2-aminothiazole(PAN-AT), was synthesized simply by the reaction of polyacrylonitrilewith 2-aminothiazole. Optimization of the PAN-AT synthesis was carriedout at different temperatures, different molar ratios of reagents,and different time intervals in N,N-dimethylformamide (DMF) using response surface methodology (RSM)for the first attempt. The functional group capacity (the contentof the functional group) and the percentage conversion of the functionalgroup of PAN-AT prepared under the optimum conditions were 3.94 mmol/gand 41.10%, respectively. The structure of PAN-AT was characterizedby elemental analysis and FTIR. Meanwhile, the adsorption propertiesof the resin for Hg(II) were investigated by batch and column experiments.The results suggested that the resin possessed much better adsorptioncapability for Hg(II) than for other metal ions and the maximum saturatedadsorption capacity estimated from the Langmuir model was 454.9 mg/gat 308 K. Furthermore, the resin could be regenerated through thedesorption of the Hg(II) anions using 3.0 mol/L HNO3solutionand could be reused to adsorb again. Finally, the resin and its metalcomplexes were studied by SEM, TGA, and energy dispersive X-ray spectroscopy(EDS). Also, the PAN-AT chelating resin could provide a potentialapplication for a treatment process of Hg(II) contaminated wastewater. [ABSTRACT FROM AUTHOR]

The ruthenium(II)-catalyzed direct ring-opening reaction of 7-azabenzonorbornadienes with anilides via C-H activation to access hydronaphthylamines has been developed. The transformation proceeds with a high stereoselectivity to give cis-configuration products under redox-neutral conditions.

The first example of oxidant-free cobalt-catalyzed synthesis of five-membered spirocycles is reported from benzimidates and maleimides utilizing nitrobenzene as promoter. In contrast to previously known cobalt-catalyzed oxidative C-H functionalization reactions, this transformation occurs efficiently in the absence of oxidant and is accompanied by liberation of hydrogen. The spiro-lactams were readily achieved by the hydrolysis of as-prepared spirocyclic compounds. The Cp*Rh(III) catalyst shows poor reactivity.

The mechanisms and origins for the Pd- and Ni-catalyzed regioselective hydrosilylation of allene have been investigated by means of density functional theory (DFT) calculations. The free-energy profiles of Pd- and Ni-catalyzed reactions with small and bulky N-heterocyclic carbene (NHC) ligands are calculated to determine the mechanism for regioselectivities. The calculation results show that different metals (Ni vs Pd) lead to regiochemical reversals for the hydrosilylation of allene. The allylsilane is the major product via palladium catalysis with small NHC ligand, while the vinylsilane is the major product via nickel catalysis with bulky NHC ligand. Both electronic and steric factors play a key role in the regioselectivities for the hydrosilylation of allene via Pd and Ni catalysts. The calculation results are in good agreement with observed regioselectivities and could provide insights into the design of new catalysts for the regioselectivity of hydrosilylation reactions.