Auf das Substrat abgestimmt: Chirale Liganden L* und chirale Anionen, wie in (S)‐TriP Ag, wurden in Gold(I)‐katalysierten enantioselektiven intramolekularen Additionen von Hydrazinen und Hydroxylaminen an Allene eingesetzt. Diese komplementären Ansätze ebnen den Weg zu den Titelverbindungen in chiraler Form. PNB=para‐Nitrobenzoyl.

Two molybdenum(VI) complexes bearing a C3 symmetrical amino tris-tert-butylphenolate ligand have proved to be air- and water-tolerant catalysts that efficiently catalyse, in high yields and selectivity, the oxidation of sulfides, olefins and halides. In particular high turnover frequencies and turnover numbers (TOF and TON) have been obtained for the cyclooctene epoxidation (catalyst loading down to 0.05%, TONs up to 88,000 and TOFs up to 7500 h−1)

Chiral ligands (L*) and chiral anions [(S)-TriPAg] are employed in the gold(I)-catalyzed enantioselective intramolecular additions of hydrazines and hydroxylamines to allenes. These complementary methods allow access to chiral vinyl isoxazolidines, oxazines, and differentially protected pyrazolidines. PNB=para-nitrobenzoy

In this work, we present novel fullerene (C60) end-capped rod-like polypeptide-polymers, obtained by one-pot thiol-ene chemistry. These systems are able to self-assemble in water creating precise bulky microstructures of toroidal or vesicular shapes. Independent molecular dynamics simulations supported the observed experimental results.

[reaction: see text] The stereoselective Rh(I)-catalyzed conjugate addition reaction of aryl and alkenylboronic acids to unprotected 2-phenyl-4-hydroxycyclopentenone is presented. The free OH group on the substrate is responsible for the stereochemistry, which is cis for arylboronic derivatives. In the case of the alkenylboronic compounds, the stereochemistry can be tuned to either a cis (bases as additives) or trans addition (CsF as additive) without the need of protecting groups.

The low solubility of carbon nanostructures (CNs) in water and the need of ordered architectures at the nanoscale level are two major challenges for materials chemistry. Here we report that a novel amino acid based low-molecular-weight gelator (LMWG) can be used to effectively disperse pristine CNs in water and to drive their ordered self-assembly into supramolecular hydrogels. A non-covalent mechanochemical approach has been used, so the π-extended system of the CNs remains intact. Optical spectroscopy and electron microscopy confirmed the effective dispersion of the CNs in water. Electron microscopy of the hydrogels showed the formation of an ordered, LMWG-assisted, self-assembled architecture. Moreover, the very same strategy allows the solubilization and self-assembly in water of a variety of hydrophobic molecules.

The removal of dyes and pharmaceuticals from water has become a major issue in recent years due to the shortage of freshwater resources. The adsorption of these pollutants through nontoxic, easy-to-make, and environmentally friendly adsorbents has become a popular topic. In this work, a tetrapeptide–pyrene conjugate was rationally designed to form hydrogels under controlled acidic conditions. The hydrogels were thoroughly characterized, and their performance in the adsorption of various dyes and pharmaceuticals from water was investigated. The supramolecular hydrogel efficiently adsorbed methylene blue (MB) and diclofenac (DCF) from water. The effect of concentration in the adsorption efficiency was studied, and results indicated that while the adsorption of MB is governed by the availability of adsorption sites, in the case of DCF, concentration is the driving force of the process. In the case of MB, the nature of the dye–hydrogel interactions and the mechanism of the adsorption process were investigated through UV–Vis absorption spectroscopy. The studies proved how this dye is first adsorbed as a monomer, probably through electrostatic interactions; successively, at increasing concentrations as the electrostatic adsorption sites are depleted, dimerization on the hydrogel surface occurs.

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