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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]

While monetary rewards have been widely used by online platforms to motivate user-generated content (UGC) contributions, users may not always demonstrate the expected behaviors. Unintended consequences of reward policies, exemplified by unchanged or reduced UGC contributions, may occur. Through two natural experiments, this study investigates the implications of providing users with an incentive structure that rewards users' continued contribution according to the volume of UGC. Using a unique data set on two completion-contingent incentive programs from a popular online aesthetic medicine platform, we examine user responses to reward thresholds. We found that after users reach a threshold to obtain a monetary reward, they are less likely to continue contributing UGC, suggesting a minimal-effort effect. Our findings indicate that social approval from peers helps to mitigate unintended user responses to monetary reward policies. We also observed that monetary rewards primarily improve the quality and website traffic of low- to moderate-quality contributions. [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 molecular belt incorporating naphthalene moieties, featuring an ellipsoidal cavity, was precisely engineered through bottom–up synthesis. Its pre-arranged geometry exhibits excellent complementarity to fullerene C70, resulting in remarkable selective binding ability (K = 1.3 × 106 M−1) for C70 compared to C60 (K = 176 M−1), forming a 1 : 1 complex. This superiority was unequivocally demonstrated by the single crystal structure of the complex, which revealed outstanding concave–convex shape complementarity between the two components. This highlights the potential application of molecular belts in the purification and separation of fullerenes. [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]

A molecular belt incorporating naphthalene moieties, featuring an ellipsoidal cavity, was precisely engineered through bottom–up synthesis. Its pre-arranged geometry exhibits excellent complementarity to fullerene C70, resulting in remarkable selective binding ability (K = 1.3 × 106 M−1) for C70 compared to C60 (K = 176 M−1), forming a 1 : 1 complex. This superiority was unequivocally demonstrated by the single crystal structure of the complex, which revealed outstanding concave–convex shape complementarity between the two components. This highlights the potential application of molecular belts in the purification and separation of fullerenes. [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 C 3 -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 Ni 2+ ion immobilization while maintaining crystallinity. The resulting Ni 2+ -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., (© 2024 Wiley-VCH GmbH.)

A molecular belt incorporating naphthalene moieties, featuring an ellipsoidal cavity, was precisely engineered through bottom-up synthesis. Its pre-arranged geometry exhibits excellent complementarity to fullerene C 70 , resulting in remarkable selective binding ability ( K = 1.3 × 10 6 M -1 ) for C 70 compared to C 60 ( K = 176 M -1 ), forming a 1 : 1 complex. This superiority was unequivocally demonstrated by the single crystal structure of the complex, which revealed outstanding concave-convex shape complementarity between the two components. This highlights the potential application of molecular belts in the purification and separation of fullerenes.

A novel one-pot two-step multicomponent reaction has been achieved for the preparation of β-CF 3 enamines by using different aliphatic amines, propiolates, and CF 3 SO 2 Na 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-CF 3 enamines were obtained in moderate to good yields. Among them, the primary aliphatic amines only gave pure (E)-β-CF 3 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(sp 2 )-H involves radical process., (© 2023 Wiley-VCH GmbH.)