The Research on Porphyrins and Analogues in Brazil: A Small Review Covering Catalytic and other Applications since the Beginning at Universidade de São Paulo in Ribeirão Preto until the Joint Venture between Brazilian Researchers and Colleagues from Universidade de Aveiro, Portugal

Abstract

The synthetic versatility and the potential applications of porphyrins and analogues in different fields have aroused special interest in their study, especially to mimic biological systems, such as cytochrome P-450. The ability of the porphyrin tetrapyrrolic core to accommodate metal ions of varying charges can modulate the type of application of these compounds. As a contribution, in this special number in honor to the Brazilian women who have devoted their lives to the growth and dissemination of chemistry knowledge, we report the advances in porphyrin research in Brazil for catalytic purposes and other applications, beginning at the Universidade de São Paulo (USP) at Ribeirão Preto. We also discuss some works that have resulted from joint research effort between Brazilian researchers and Portuguese colleagues from the Universidade de Aveiro, Portugal, working in the porphyrin field.

SERS Enhancement of Porphyrin-Type Molecules on Metal-Free Cellulose-Based Substrates

“…The chemical structures of a cellulose molecule and the porphyrin-type molecules used as analytes are shown in Figure a,b, respectively. In the study, we used a wide variety of porphyrins, including neutral hydrophobic tetraphenyl porphyrin (TPP), as well as water-soluble molecules: two cationic species (TMPyP neutralized by Cl – ions and TMAP with p -toluenesulfonic acid used as counterion) and two anionic species (TPPS neutralized by Na + and TCPP neutralized by H + ). , The cellulose nanofiber (CNF) platform was prepared by drop-casting a nanofiber dispersion on a silicon piece and drying out the solvent. Figure c shows a scanning electron microscopy (SEM) image of the substrate fabricated using a highly concentrated (1 wt %) cellulose dispersion showing a thick layer of randomly distributed nanofibers.…”

Degradation of Dyes Catalyzed by Aminophenyl-Substituted Mn-Porphyrin Immobilized on Chloropropyl Silica Gel and Evaluation of Phytotoxicity

“…11 Since then, different strategies have been implemented by the scientific community to increase the efficiency of these catalytic systems, such as the introduction of functional groups on the periphery of the porphyrin macrocycle, 8 the use of additives such as imidazole and water 12,13 and immobilization on different inorganic and/ or organic supports. 14 The immobilization of metalloporphyrins on chemical supports and their use in heterogeneous catalytic processes appears as an alternative to overcome the limitations inherent to homogeneous systems. 15−21 A variety of supports, both organic and inorganic, have been used to anchor (immobilize and support) metalloporphyrins.…”

“…The use of metalloporphyrins as CYP biomimetic catalysts has been carried out since the 1980s . Since then, different strategies have been implemented by the scientific community to increase the efficiency of these catalytic systems, such as the introduction of functional groups on the periphery of the porphyrin macrocycle, the use of additives such as imidazole and water , and immobilization on different inorganic and/or organic supports …”

Photocatalytic degradation of methyl orange mediated by a silica coated nanomagnet porphyrin hybrid

“…Metalloporphyrins and analogues have already proved their efficiency as catalysts, namely for oxidative reactions [11][12][13][14][15][16][17][18][19][20]. Porphyrins are also efficient producers of reactive oxygen species (ROS) in the presence of light, such as singlet oxygen ( 1 O2) [21][22][23][24], thus inducing many photocatalytic reactions [25,26].…”