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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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Experimental measurements are combined with mathematical modeling in order to investigate the selective absorption of aromatic molecules (benzene, phenol, and toluene) from aqueous solutions by syndiotactic polystyrene (sPS) monolithic aerogels. The experimental results with aqueous solutions of a single aromatic compound show high absorption efficiency for the non-polar compounds (toluene: ≈94%; benzene: ≈77%), whereas phenol (polar compound) is poorly absorbed with an efficiency of about 12%. Furthermore, phenol is no way removed from aqueous phase in presence of NaCl while the water salinity do not affect the absorption efficiency toward toluene and benzene in ternary aqueous solution, evidencing also that toluene is preferentially uptaken by aerogels with a superior kinetic and higher diffusivity constant with respect to benzene. The results obtained in this work underline that sPS aerogels can be interesting materials to selectively recover non-polar compounds from seawater by means of an absorption process.

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Functionalized Isoindolinones. -Synthesis of highly functionalized 3-isoindolinones is achieved by the present new electroreductively-catalyzed reaction of 1,3-dicarbonyl compounds with cyanobenzaldehyde (I). The desired products are obtained under mild conditions and in short reaction times by galvanostatic electrolysis in a divided cell. In contrast, cyclohexanedione (XI) gives product (XII) instead of the desired product due to electro-initiated Knoevenagel-Michael reaction. Isoindolines (III) and (XIV) subsequently undergo Michael addition with acrylates (IV) or, this reaction is performed in one pot giving functionalized adducts (V) and (XIV), respectively. Furthermore, additional Michael reaction with acrolein (VI) gives novel tricyclic isoindolines like (VII) with high diastereoselectivity. -(ANTICO, P.; CAPACCIO, V.; DI MOLA, A.; MASSA*, A.; PALOMBI, L.; Adv. Synth. Catal. 354 (2012) 9, 1717-1724, http://dx.