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Huge annual consumption of thermoplastics results in the generation of large amounts of waste after their service life. Currently, the most popular recycling method based on mechanically melt‐reprocessing deteriorates the material performance and is economically unattractive, which makes it unviable to be implemented in large scale. Herein, we present a chemical upcycling strategy that can transform dimethylglyoxime‐urethane based thermoplastic waste into thermoset product with superior mechanical properties and higher economic values than the initial one. It is found that the dimethylglyoxime‐urethane moiety has dynamic nature, endowing the material with open‐loop upcycling ability. By removing the dimethylglyoxime segment via a simple sublimation process, the material structure is transformed from linear molecular into crosslinked network. More interestingly, the transformation is reversible, and the regenerated crosslinked network can be transformed back to linear molecule by returning the removed dimethylglyoxime segment to the material, which means the upcycled product can be recycled again after its service life. Our linear/crosslinked transformation strategy provide a new option for recycling thermoplastic waste. [ABSTRACT FROM AUTHOR]

Asymmetric aminoazidation and diazidation of alkenes are straightforward strategies to build value‐added chiral nitrogen‐containing compounds from feedstock chemicals. They provide direct access to chiral organoazides and complement enantioselective diamination. Despite the advances in non‐asymmetric reactions, asymmetric aminoazidation or diazidation based on acyclic systems has not been previously reported. Here we describe the iron‐catalyzed intermolecular asymmetric aminoazidation and diazidation of styrenes. The method is practically useful and requires relatively low loading of catalyst and chiral ligand. With mild reaction conditions, the reaction can be completed on a 20 mmol scale. Studies of the mechanism suggest that the reaction proceeds via a radical pathway and involves stereocontrol of an acyclic free radical which probably takes place through a group transfer mechanism. [ABSTRACT FROM AUTHOR]

Single‐atom catalysts have demonstrated their superiority over other types of catalysts for various reactions. However, the reported nitrogen reduction reaction single‐atom electrocatalysts for the nitrogen reduction reaction exclusively utilize metal–nitrogen or metal–carbon coordination configurations as catalytic active sites. Here, we report a Fe single‐atom electrocatalyst supported on low‐cost, nitrogen‐free lignocellulose‐derived carbon. The extended X‐ray absorption fine structure spectra confirm that Fe atoms are anchored to the support via the Fe‐(O‐C2)4 coordination configuration. Density functional theory calculations identify Fe‐(O‐C2)4 as the active site for the nitrogen reduction reaction. An electrode consisting of the electrocatalyst loaded on carbon cloth can afford a NH3 yield rate and faradaic efficiency of 32.1 μg h−1 mgcat.−1 (5350 μg h−1 mgFe−1) and 29.3 %, respectively. An exceptional NH3 yield rate of 307.7 μg h−1 mgcat.−1 (51 283 μg h−1 mgFe−1) with a near record faradaic efficiency of 51.0 % can be achieved with the electrocatalyst immobilized on a glassy carbon electrode. [ABSTRACT FROM AUTHOR]