Applications of Selectfluor for the oxidation of Sulfides, urazoles and alcohols under the solvent-free conditions

: Selectfluor acts as a safe and efficient reagent for the oxidation of urazoles, alcohols and also sulfides via releasing the electrophile F under the solvent-free conditions. In room temperature, this reagent cannot oxidize the substrates alone and requires KBr as the catalyst. In the proposed mechanism, Selectfluor converts the Br- to the Br-F and the lone-pair electron of substrates attack to Br-F to perform the oxidation reaction. This procedure offers some advantages; for example short reaction time, simple work-up, good yield and matching with some green chemistry approaches.

Structure and Stability of Aromatic Nitrogen Heterocycles Used in the Field of Energetic Materials

Understanding the stabilization of nitrogen heterocycles is critical in the field of energetic materials and calls for innovative knowledge of nitrogen aromatics. Herewith, we report for the first time that nitrogen lone pair electron (NLPE) delocalization in five-membered nitrogen heterocycles creates a second σ-aromaticity in addition to the prototypical π-aromaticity. The NLPE delocalization and the attendant dual-aromaticity are enhanced as more carbon atoms in the ring are substituted by unsaturated nitrogen atoms. The presence of adjacent nitrogen atoms in the ring can enhance the aromaticity of the nitrogen heterocycles and improve in-crystal intermolecular binding strength but will decrease the firmness of the individual molecular architecture. Notably, such σ-aromaticity is not present in six-membered nitrogen heterocycles, probably due to the longer bonds and broader regions of their rings; therefore, six-membered heterocycles present overall lower aromaticity than five-membered heterocycles. This work brings new knowledge to nitrogen aromatics and is expected to inspire broad interest in the chemistry community.

X-ray excited ultralong room-temperature phosphorescence for organic afterglow scintillators

An X-ray excited organic afterglow scintillator is realized by embedding lone-pair electron involved n–π* transitions and charge transfer characters into H-aggregations.

Lone pair electron effect induced differences in linear and nonlinear optical properties of bismuth borates

We analyzed systematically each phase of BIBO, and we found that the synergistic effect between bismuth oxygen polyhedra and boron–oxygen groups codetermines the optical properties of BIBO.

Synthesis of Silane-Based Poly(thioether) via Successive Click Reaction and Their Applications in Ion Detection and Cell Imaging

A series of poly(thioether)s containing silicon atom with unconventional fluorescence were synthesized via successive thiol click reaction at room temperature. Although rigid π-conjugated structure did not exist in the polymer chain, the poly(thioether)s exhibited excellent fluorescent properties in solutions and showed visible blue fluorescence in living cells. The strong blue fluorescence can be attributed to the aggregation of lone pair electron of heteroatom and coordination between heteroatom and Si atom. In addition, the responsiveness of poly(thioether) to metal ions suggested that the selectivity of poly(thioether) to Fe3+ ion could be enhanced by end-modifying with different sulfhydryl compounds. This study further explored their application in cell imaging and studied their responsiveness to Fe3+ in living cells. It is expected that the described synthetic route could be extended to synthesize novel poly(thioether)s with superior optical properties. Their application in cell imaging and ion detection will broaden the range of application of poly(thioether)s.