Nanocellulose has received enormous scientific interest for its abundance, easy manufacturing, biodegradability, and low cost. Cellulose nanocrystals (CNCs) and cellulose nanofibers (CNFs) are ideal candidates to replace plastic coating in the textile and paper industry. Thanks to their capacity to form an interconnected network kept together by hydrogen bonds, nanocelluloses perform an unprecedented strengthening action towards cellulose‐ and other fiber‐based materials. Furthermore, nanocellulose use implies greener application procedures, such as deposition from water. The surface chemistry of nanocellulose plays a pivotal role in influencing the performance of the coating: tailored surface functionalization can introduce several properties, such as gas or grease barrier, hydrophobicity, antibacterial and anti‐UV behavior. This review summarizes recent achievements in the use of nanocellulose for paper and textile coating, evidencing critical aspects of coating performances related to deposition technique, nanocellulose morphology, and surface functionalization. Furthermore, beyond focusing on the aspects strictly related to large‐scale coating applications for paper and textile industries, this review includes recent achievements in the use of nanocellulose coating for the safeguarding of Cultural Heritage, an extremely noble and interesting emerging application of nanocellulose, focusing on consolidation of historical paper and archaeological textile. Finally, nanocellulose use in electronic devices as an electrode modifier is highlighted.

This review describes the progress of the last decade on the synthesis of substituted benzofurans, which are useful scaffolds for the synthesis of numerous natural products and pharmaceuticals. In particular, new intramolecular and intermolecular C–C and/or C–O bond-forming processes, with transition-metal catalysis or metal-free are summarized. (1) Introduction. (2) Ring generation via intramolecular cyclization. (2.1) C7a–O bond formation: (route a). (2.2) O–C2 bond formation: (route b). (2.3) C2–C3 bond formation: (route c). (2.4) C3–C3a bond formation: (route d). (3) Ring generation via intermolecular cyclization. (3.1) C7a-O and C3–C3a bond formation (route a + d). (3.2) O–C2 and C2–C3 bond formation: (route b + c). (3.3) O–C2 and C3–C3a bond formation: (route b + d). (4) Benzannulation. (5) Conclusion.

The new motif – α,α-difluoromethyl thioamide – has been assembled starting from isothiocyanate (as thioamide precursor) and a formal difluoromethyl-carbanion generated from commercially available TMSCHF2.

New heteroaryl HIV-protease inhibitors bearing a carbamoyl spacer were synthesized in few steps and high yield, from commercially available homochiral epoxides. Different substitution patterns were introduced onto a given isopropanoyl-sulfonamide core that can have either H or benzyl group. The in vitro inhibition activity against recombinant protease showed a general beneficial effect of both carbamoyl moiety and the benzyl group, ranging the IC 50 values between 11 and 0.6 nM. In particular, benzofuryl and indolyl derivatives showed IC 50 values among the best for such structurally simple inhibitors. Docking analysis allowed to identify the favorable situation of such derivatives in terms of number of interactions in the active site, supporting the experimental results.The inhibition activity was also confirmed in HEK293 mammalian cells and was maintained against protease mutants. Furthermore, the metabolic stability was comparable with that of the commercially available inhibitors.

This review gives an overview on recent developments in methods for the construction of compounds with the 2,3-dihydrobenzo­furan core in the period 2012 to 2019. Interest in 2,3-dihydrobenzofurans is constantly increasing. The methods are divided into intermolecular and intramolecular approaches. Intermolecular approaches are subdivided according to the parent intermediate for the key reaction, while intermolecular approaches are subdivided according by which bond is formed in the key reaction. The transformation of benzofurans to dihydrobenzofurans and other miscellaneous methods are also discussed. Approaches useful for the synthesis of natural products are emphasized.1 Introduction2 Intermolecular Approaches2.1 o-Quinone Methides and o-Quinones2.2 p-Quinone Methides and p-Quinones2.3 Nitrogen-Containing Phenols and Quinones2.4 o-Hydroxyphenylcarbonyl Derivatives and Phenols2.5 Miscellaneous3 Intramolecular Approaches3.1 O–C2 Bond Forming3.2 C2–C3 Bond Forming3.3 C3–Aryl Bond Forming3.4 O–Aryl Bond Forming4 From BF to DHB5 Rearrangements and Aromatizations

We investigated the effects of solvent fractionation on the chemical structures of two commercial technical lignins. We compared the effect of Soxhlet and Kumagawa extraction. The aim of this work was to compare the impact of the methods and of the solvents on lignin characteristics. Our investigation confirmed the potentialities of fractionation techniques in refining lignin properties and narrowing the molecular weight distribution. Furthermore, our study revealed that the Kumagawa process enhances the capacity of oxygenated solvents (ethanol and tetrahydrofuran) to extract lignin that contains oxidized groups and is characterized by higher average molecular weights. Furthermore, the use of tetrahydrofuran after ethanol treatment enabled the isolation of lignin with a higher ratio between carbonyl and other oxidized groups. This result was confirmed by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), 13 C NMR and two-dimensional (2D) NMR spectroscopies, gel permeation chromatography (GPC), and analytical pyrolysis-gas chromatography–mass spectrometry (Py-GC–MS) analysis. Ultraviolet–visible (UV–vis) spectra evidenced the enrichment in the most conjugated species observed in the extracted fractions. Elemental analyses pointed at the cleavage of C-heteroatom bonds enhanced by the Kumagawa extraction.

Lignin is an abundant biopolymer deriving from industrial pulping processes of lignocellulosic biomass. Despite the huge amount of yearly produced lignin waste, it finds scarce application as a fine material and is usually destined to be combusted in thermochemical plants to feed, with low efficiency, other industrial processes. So far, the use of lignin in materials science is limited by the scarce knowledge of its molecular structure and properties, depending also on its isolation method. However, lignin represents an intriguing feedstock of organic material. Here, the structural and chemical‐physical characteristics of two kraft lignins, L1 and L2, are analyzed. First, several molecular characterization techniques, such as attenuated total reflectance ‐ Fourier transform infrared spectroscopy, elemental analyses, gel permeation chromatography, evolved gas analysis‐mass spectrometry, UV–vis, 31P‐ and 13C‐ nuclear magnetic resonance spectroscopies are applied to get insights into their different structures and their degree of molecular degradation. Then, their efficient application as gate dielectric materials is demonstrated for organic field‐effect transistors, finding the increased capacity of L1 with respect to L2 in triggering functional and efficient devices with both p‐type and n‐type organic semiconductor molecules.

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