Nanoporous-crystalline (δ and ε form) fibers of syndiotactic polystyrene (s-PS) have been prepared from melt-spun fibers by different guest-induced cocrystallization procedures. Their crystal structure, morphology, and uptake of volatile organic compounds (VOC) have been investigated. The use of chloroform, i.e., of a molecule being a suitable guest for both δ and ε forms but also a strong solvent for s-PS, leads to nanoporous-crystalline fibers with VOC sorption kinetics much faster than for s-PS nanoporous-crystalline powders and films and comparable with those of nanoporous-crystalline s-PS aerogels. This unexpected phenomenon is due to etching of the melt-spun fibers by chloroform that exposes internal fibrils and markedly increases the surface area up to 165 m 2 /g. Etched δ form fibers are more effective for sorption of most pollutants while etched ε form fibers are much more effective in sorption of long organic molecules, like ndecane. Outstanding sorption properties, simple preparation processes (easily scalable at the industrial level), and safe morphology make etched nanoporous-crystalline s-PS fibers particularly suitable as sorption media for VOC removal from water and air.
A tandem aldol–heterocyclization–rearrangement reaction and one‐pot sequential Michael addition allowed a direct access to highly functionalized 3‐isoindolinones containing quaternary carbon centers. The desired products are obtained under mild conditions and in short reaction times by galvanostatic electrolysis in a divided cell. A further tandem intramolecular heterocyclization reaction leading to synthetically relevant hemiaminal derivatives has been established with suitable Michael acceptors.
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