Neste trabalho, reportamos a síntese, caracterização e atividade de catecolase do complexo binuclear de cobre [Cu 2 (H 2 bbppnol)(µ-OAc)(µ-ClO 4)] ClO 4 •H 2 O•EtOAc contendo o ligante N,N'-2-hidroxibenzil-N,N'-2-piridilmetil-2-hidroxipropano-1,3-diamina (H 3 bbppnol). O complexo foi caracterizado através de espectroscopias no infravermelho e eletrônica, ressonância paramagnética eletrônica, medidas de susceptibilidade magnética e cristalografia de raios-X. A atividade de catecolase do complexo foi determinada espectrofotometricamente, monitorando-se a oxidação do substrato 3,5-di-terc-butilcatecol à correspondente o-benzoquinona, em solução de metanol saturada com O 2 /tampão aquoso (pH 8), a 25 o C. O complexo mostrou-se capaz de oxidar o substrato modelo com uma constante catalítica de 0,0057 s-1. The synthesis, characterization and catecholase activity studies of the complex [Cu 2 (H 2 bbppnol)(µ-OAc)(µ-ClO 4)]ClO 4 •H 2 O•EtOAc containing the dinucleating ligand N,N'-2-hydroxybenzyl-N,N'-2-pyridylmethyl-2-hydroxypropane-1,3-diamine (H 3 bbppnol) are presented here. The complex was characterized by IR, electronic and EPR spectroscopies, cyclic voltammetry, magnetic susceptibility measurements and X-ray crystallography. The catecholaselike activity of the complex was determined spectrophotometrically by monitoring the oxidation of 3,5-di-tert-butylcatechol to the corresponding o-benzoquinone in O 2-saturated methanol/aqueous buffer (pH 8) mixtures at 25ºC. The complex was able to oxidize the model substrate with a turnover number of 0.0057 s-1 .

We have developed a green and efficient protocol for the chalcogenation of bicyclic arenes by using I2/DMSO as catalytic system under solvent‐ and metal‐free conditions. This protocol allows access to several chalcogenated bicyclic arenes through C(sp2)–H bond functionalization, in good to excellent yields by using microwave irradiation or conventional heating.

The iron complex converted higher amounts of substrates while the copper complex presented higher selectivity toward selected products.

4-(Nitrostyryl)phenols 2a-9a were synthesized, and by deprotonation in solution, the solvatochromic phenolates 2b-9b were formed. Their absorption bands in the vis region of the spectra are due to π-π* electronic transitions, of an intramolecular charge-transfer nature, from the electron-donor phenolate toward the electron-acceptor nitroarene moiety. The frontier molecular orbitals and natural bond orbitals were analyzed for the protonated and deprotonated forms. The calculated geometries are in agreement with X-ray structures observed for 4a, 6a, and 8a. The HOMO-LUMO energy gaps suggest that, after their deprotonation, an increase in the electron delocalization is observed. In the protonated compounds, the HOMO is primarily localized over the phenol ring and the C═C bridge. After deprotonation, it extends toward the entire molecule, including the NO2 groups. The solvatochromism of each dye was studied in 28 organic solvents, and it was found that all compounds exhibit a reversal in solvatochromism, which is interpreted in terms of the ability of the media to stabilize their electronic ground and excited states to different extents. The Catalán multiparameter equation is used in the interpretation of the solvatochromic data, revealing that the most important contribution to the solute/solvent interaction is the hydrogen-bond donor acidity of the solvent.

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