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Despite that two-dimensional transition metal carbides and carbonitrides (MXenes) are burgeoning candidates for remediation of environmental pollutants, the construction of robust functionalized MXene nanosheets with a high affinity for target heavy metal ions and radionuclides remains a challenge. Here we report the successful placement of amidoxime chelating groups on Ti3C2Tx MXene surface by diazonium salt grafting. The introduction of amidoxime functional groups significantly enhances the selectivity of Ti3C2Tx nanosheets for uranyl ions and also greatly improves their stability in aqueous solution, enabling efficient, rapid, and recyclable uranium extraction from aqueous solutions containing competitive metal ions. Benefiting from the excellent conductivity of MXenes, the amidoxime functionalized Ti3C2Tx nanosheets show outstanding electrochemical performance such that when loaded on carbon cloth the application of an electric field increases the uranium adsorption capacity from 294 to 626 mg/g, outperforming all organic electrochemical sorption materials reported previously. The present work provides an effective strategy to functionalize MXene nanosheets with fundamental implications for the design of MXene-based selective electrosorption electrode materials.

As the isosteric or bio-isosteric analogues of the corresponding β-amino acid, β-aminophosphonates and -phosphinates have diverse and interesting biological and biochemical properties. This article reviews the recent studies on the asymmetric synthesis of optically active β-aminophosphonates and -phosphinates by auxiliary induced, enzymatic resolution and catalyst catalysed methods.

Jipan Yu, Hua Fu Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, People's Republic of China Abstract: N-heterocycles are important motifs in natural products and pharmaceuticals. Recently, the transition metal–catalyzed C-H amination has become a subject in the synthesis of N-heterocycles because of use of the readily available starting materials, high efficiency, economy, and practicability of the methods. This review summarizes recent advances in the copper, iron, palladium, rhodium, ruthenium, and nickel-catalyzed synthesis of N-heterocycles via C-H amination strategy. Keywords: N-heterocycles, C-H activation, amination, transition metal–catalyzed, synthetic methods