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Organic–inorganic hybrid phase–transition molecular materials have attracted increasing attention due to their excellent properties of combining inorganic and organic components. However, few research has been conducted on rare‐earth–based bimetallic organic–inorganic hybrids. Here, we successfully constructed a series of rare–earth–based organic–inorganic hybrid multifunctional materials, (C6H14N2)2EuX(NO3)6O2 (X=Na, K, Rb), with reversible phase transition, switchable dielectric, photoluminescence and semiconductor properties. Specifically, the phase‐transition temperature of three compounds are determined to be 364, 405 and 440 K, respectively. By the confinement effect caused by the variation of alkali metal elements in the two–dimensional structure, the phase transition temperature is successfully increased by 76 K. Meanwhile, the solid–state photoluminescence of three compounds displays bright red light at room temperature. Additionally, the bandgaps of three compounds are determined to be 3.21, 3.53 and 3.32 eV, respectively. It is expected that the strategy of alkali metal substitution proposed in this work will provide new thoughts for the design of multifunctional organic‐inorganic hybrid crystals. [ABSTRACT FROM AUTHOR]

The active site of pyruvate kinase (PYK) is located between the AC core of the enzyme and a mobile lid corresponding to domain B. Many PYK structures have already been determined, but the first `effector-only' structure and the first with PEP (the true natural substrate) are now reported for the enzyme from Trypanosoma brucei. PEP soaked into crystals of the enzyme with bound allosteric activator fructose 2,6-bisphosphate (F26BP) and Mg2+ triggers a substantial 23° rotation of the B domain ` in crystallo', resulting in a partially closed active site. The interplay of side chains with Mg2+ and PEP may explain the mechanism of the domain movement. Furthermore, it is apparent that when F26BP is present but PEP is absent Mg2+ occupies a position that is distinct from the two canonical Mg2+-binding sites at the active site. This third site is adjacent to the active site and involves the same amino-acid side chains as in canonical site 1 but in altered orientations. Site 3 acts to sequester Mg2+ in a `priming' position such that the enzyme is maintained in its R-state conformation. In this way, Mg2+ cooperates with F26BP to ensure that the enzyme is in a conformation that has a high affinity for the substrate. [ABSTRACT FROM AUTHOR]

A highly regio- and stereoselective metal-free method for the intramolecular oxidative aminofluoration of unactivated terminal alkenes is presented. [ABSTRACT FROM AUTHOR]

Aryl iodides such as Ph-I, Tol-I, and Mst-I efficiently promote the process. [ABSTRACT FROM AUTHOR]