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Natural amino acids are the most important building blocks in supramolecular chemistry which possess the best biocompatibility in nature. To the best of our knowledge, although hydrogels based on amino acid derivatives have already been studied widely, there is still no report about natural amino acids hydrogels constructed by metal ions induction method. Herein, the self‐assembly behaviors of twelve natural amino acids with eight metal ions were studied systematically. It is surprising that only sodium L‐Phenylalanine can self‐assemble into hydrogel with ZnCl2. Various methods were used to investigate the formation mechanism of hydrogel. The formation of hydrogel is triggered mainly via π‐π stacking and metal‐ligand interactions. Moreover, this green L‐Phenylalanine hydrogel displays acid responsiveness and relatively stability under high temperature, which has great potential applications in many fields. [ABSTRACT FROM AUTHOR]

The rate constants of two redox reactions Fe (CN)64−+S2O82− and Fe (phen)32++S2O82− in the critical solution of 2‐butoxyethanol and water have been measured by using the UV spectrophotometry at the initial reaction stage. It was found that the rate constants at various temperatures for two reactions were well described by the Arrhenius equation in the noncritical region. The critical slowing down effect was detected in the critical region. The critical slowing down exponents were determined to be 0.044 ± 0.004 and 0.046 ± 0.005 for reactions Fe (CN)64−+S2O82− and Fe (phen)32++S2O82−, respectively. The values of the critical slowing down exponents showed that only dynamic critical slowing down effect, and no thermodynamic singularity could be observed for the two reactions. [ABSTRACT FROM AUTHOR]

Self-assembly of N-fluorenyl-9-methoxycarbonyl glutamic acid (Fmoc-Glu) in water generates metastable single-wall nanotubes. These nanotubes entangle and bundle together to form unstable gels that shrink with time and finally result in lamellar crystalline precipitates. Melamine (Mm) was employed as a supramolecular modifier and stabilizer to improve the stability of the nanotubes. Mm interacts with the carboxyl-rich surfaces of the nanotubes via H-bonds and static electronic forces to diminish the high affinity of individual nanotubes and facilitate Fmoc-Glu supergelation (critical gelation concentration <0.1 wt %). Although the basic process of nanotube formation is not disturbed, Mm inverts the supramolecular helicity of nanotubes from P to M. [ABSTRACT FROM AUTHOR]

An efficient and practical C–N bond formation methodology for the synthesis of N‐alkylated (benzo)thiazoles was developed, via the copper‐catalyzed one‐pot two‐step reactions of 2‐amino(benzo)thiazoles and aldehydes (ketones) with tosylhydrazide. This cross‐coupling reaction proceeded smoothly and tolerated a broad range of functional groups (46 examples). A variety of functionalized N‐alkylated (benzo)thiazoles were obtained in moderate to high yields. Notably, gram‐scale synthesis of fanetizole (anti‐inflammatory drug) was also realized through this protocol. [ABSTRACT FROM AUTHOR]