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A novel protocol for the visible‐light‐driven synthesis of β‐trifluoromethylated enamines has been developed, which operates without the use of transition metals or any photocatalysts, utilizing trifluoromethylthiosulfonium salts as the source of trifluoromethyl groups under mild conditions. According to this new protocol, more than 40 products have been prepared in moderate to good yields. In addition to eliminating the need for expensive or toxic transition metals and photocatalysts, this new methodology proves its potential scalability through air‐stability, the use of safe and readily available reagents, a two‐step one‐pot procedure, and effective gram‐scale reactions. This innovative approach not only demonstrates promise for green chemical synthesis but also offers a new pathway for the advancement of fluorine chemistry in sustainable organic synthesis. [ABSTRACT FROM AUTHOR]

Crown ethers (CEs), known for their exceptional host–guest complexation, offer potential as linkers in covalent organic frameworks (COFs) for enhanced performance in catalysis and host–guest binding. However, their highly flexible conformation and low symmetry limit the diversity of CE‐derived COFs. Here, we introduce a novel C3‐symmetrical azacrown ether (ACE) building block, tris(pyrido)[18]crown‐6 (TPy18C6), for COF fabrication (ACE‐COF‐1 and ACE‐COF‐2) via reticular synthesis. This approach enables precise integration of CEs into COFs, enhancing Ni2+ ion immobilization while maintaining crystallinity. The resulting Ni2+‐doped COFs (Ni@ACE‐COF‐1 and Ni@ACE‐COF‐2) exhibit high discharge capacity (up to 1.27 mAh ⋅ cm−2 at 8 mA ⋅ cm−2) and exceptional cycling stability (>1000 cycles) as cathode materials in aqueous alkaline nickel‐zinc batteries. This study serves as an exemplar of the seamless integration of macrocyclic chemistry and reticular chemistry, laying the groundwork for extending the macrocyclic‐synthon driven strategy to a diverse array of COF building blocks, ultimately yielding advanced materials tailored for specific applications. [ABSTRACT FROM AUTHOR]

A novel one‐pot two‐step multicomponent reaction has been achieved for the preparation of β‐CF3 enamines by using different aliphatic amines, propiolates, and CF3SO2Na as starting material. In this protocol, various aliphatic amines including primary amines, cyclic or acyclic secondary amines were demonstrated to be good coupling partners, and different β‐CF3 enamines were obtained in moderate to good yields. Among them, the primary aliphatic amines only gave pure (E)‐β‐CF3 enamines as products. The synthetic utility of the MCRs strategy was further demonstrated by mild conditions, gram‐scale synthesis and natural sunlight‐induced protocol. Preliminary mechanistic studies suggest that this trifluoromethylation of C(sp2)−H involves radical process. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of 1‐methylcyclopropene (1‐MCP), chitosan (CTS), and combined 1‐MCP and CTS (1‐MCP&CTS) on the postharvest quality, bioactive compounds, antioxidant enzymes, and antioxidant capacity in Hui jujube during cold storage (0 ± 1°C and 90% ± 5% relative humidity for 75 d). The 1‐MCP&CTS treatment inhibited respiration rate and ethylene production, delayed the degradation of total soluble solids and titratable acid, and alleviated the decreases in total polyphenols, total flavonoids, anthocyanins, and ascorbic acid during storage. Compared to the control fruit, 1‐MCP&CTS treatment resulted in higher activities of superoxide dismutase, catalase, and ascorbate peroxidase and higher antioxidant capacity. The antioxidant capacity was positively correlated with the contents of bioactive compounds and antioxidant enzymes and negatively correlated with respiration rate and ethylene production. The results suggest that 1‐MCP and CTS can be applied to maintain the antioxidant systems and delay the senescence of jujube fruit. Novelty impact statement: The effects of 1‐MCP, CTS, and 1‐MCP&CTS during jujube storage were evaluated.Among treatments, the combined treatment had the best preservation effect.1‐MCP&CTS maintained bioactive compounds, antioxidant capacity, and storage quality of Hui jujube. [ABSTRACT FROM AUTHOR]