The widespread use of poly(3‐hexylthiophene) (P3HT) in the active layers of organic solar cells indicates that it possesses chemical stability and solubility suitable for such an application. However, it would be desirable to have a material that can maintain these properties but with a smaller bandgap, which would lead to more efficient energy harvesting of the solar spectrum. Fifteen P3HT derivatives were studied using the Density Functional Theory. The conclusion is that it is possible to obtain compounds with significantly smaller bandgaps and with solubility and stability similar to that of P3HT, mostly through the binding of oxygen atoms or conjugated organic groups to the thiophenic ring. © 2013 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys., 2013

Over the years, several drugs have been developed deriving from plants to investigate possible therapeutic roles. Among them, curcuminoids and coumarins, which, display a wide range of biological activity against several strains. Therefore, it was synthesized a curcuminoids-coumarin derivative by a mechanochemical multicomponent reaction. By NMR and HRMS results confirmed the formation of a mixture of three curcuminoids-coumarin derivatives in the same sample. The Influence of time during the milling process was evaluated, resulting in a crystalline product in only 30 min. The LAG milling carried out with different solvents showed that the product is obtained regardless of the solvent polarity. Furthermore, the biological evaluation showed that the curcuminoidscoumarin derivative has better activity against S. aureus than curcumin and 4-hydroxycoumarin. Lastly, the cell viability study exhibited a decrease of cytotoxicity of the derivative, compared to curcumin, against NIH3T3 cells.

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Pyrrolo-[3,2-b]pyrroles represent a class of promising materials for application in organic electronics with interesting optoelectronic properties and great synthesis versatility, but yields obtained from varied synthetic routes are still very low, hindering their effective application for industrial purposes. In this report, we present a method for the synthesis of tetraaryl-1,4-dihydropyrrolo-[3,2-b]pyrrole derivatives by multicomponent reactions employing niobium pentachloride as a catalyst. The optical characterization of the products is also presented. Electronic structure calculations were performed to help the interpretation of the synthesis process, as well as the optical properties of the systems. Excellent yields and low reaction times were obtained, indicating that NbCl 5 is an efficient catalyst for such systems. The products show promising properties for optoelectronic applications that can be adjusted by the choice of benzaldehyde derivatives used in the synthesis.

Grape seed is a waste product from the wine and juice industries. However, vegetable oil can be extracted from it, which is a renewable chemical with a huge potential application after chemical modifications, such as epoxidation and maleinization processes. This paper therefore deals with the use of grape seed oil, to produce its epoxidized and maleinized derivatives. Both derivatives were synthesized in order to improve the conversion (99.4%), yield (98.9%) and selectivity (99.5%) values, as well as to decrease the reaction time (3 h) using cleaner energy sources and heterogeneous catalysts, which can be used 4× without regeneration and obtaining similar conversion and yield values, and at least 5× keeping high selectivity. Based on the characterization results, both grape seed oil derivatives may be applied in different fields, including polymer chemistry as a monomer, coating, and paint. In addition, they can be an option to industries that use petrochemical derivatives as precursors.