Three l-phenylalanine- or d-glucose-decorated phenylene–thiophene oligomers have been studied using UV-Vis and ECD spectroscopies in different conditions of solution aggregation and thin films, investigating the impact of chirality on their aggregation modes.

Cellulose nanocrystals (CNCs) represent intriguing biopolymeric nanocrystalline materials, that are biocompatible, sustainable and renewable, can be chemically functionalized and are endowed with exceptional mechanical properties. Recently, studies have been performed to prepare CNCs with extraordinary photophysical properties, also by means of their functionalization with organic light-emitting fluorophores. In this paper, we used the reductive amination reaction to chemically bind 4-(1-pyrenyl)butanamine selectively to the reducing termini of sulfated or neutral CNCs (S_CNC and N_CNC) obtained from sulfuric acid or hydrochloric acid hydrolysis. The functionalization reaction is simple and straightforward, and it induces the appearance of the typical pyrene emission profile in the functionalized materials. After a characterization of the new materials performed by ATR-FTIR and fluorescence spectroscopies, we demonstrate luminescence quenching of the decorated N_CNC by copper (II) sulfate, hypothesizing for these new functionalized materials an application in water purification technologies.

The surface functionalization of cellulose nanocrystals is presently considered a useful and straightforward tool for accessing very reliable biocompatible and biodegradable nanostructures with tailored physical and chemical properties. However, to date the fine characterization of the chemical appendages introduced onto cellulose nanocrystals remains a challenge, due to the low sensitivity displayed by the most common techniques towards surface functionalization. In this paper, we demonstrate the easy functionalization of cellulose nanocrystals with aliphatic and aromatic amines, demonstrating the tunability of their properties in dependence on the selected functionality. Then, we apply to colloidal suspensions of modified nanocrystals ¹ H NMR analysis to elucidate their surface structure. To the best of our knowledge, this is the first report where such investigation was performed on cellulose nanocrystals presenting both surface and reducing end modification. These results involve interesting implications for the fields of cultural heritage and of materials chemistry.

Direct arylation polymerization (DArP) represents an ecological alternative to the conventional polycondensation methodologies for the obtainment of selected conjugated polymers. To further improve the sustainability of the synthetic protocol, efforts have been focused on bypassing the use of toxic solvents or managing them under dried conditions and inert atmospheres. Although the implementation of eco-friendly and low-toxic solvents from the safety, health and environment viewpoint has recently been proposed, their compatibility with undried and aerobic reaction conditions has remained thus far unexplored. Herein, we investigated the viability of applying anisole in the preparation of poly(9,9-dioctylfluorene-2,2′-bithiophene) under undried and aerobic conditions by employing the catalytic system comprising (PPh₃)₂PdCl₂/P(o-Anisyl)₃/Cs₂CO₃ in the presence of pivalic acid as the proton transfer agent. We assessed that the polymerization afforded satisfactory results without activating radical pathways or incorporation of structural defects in the obtained polymers. The same aerobic conditions were adopted for the copolymerization of differently structured units affording molecular weights up to 16 500 Da, thus consolidating the C–H activation route as an eco-friendly protocol for the preparation of conjugated polymers.