Synthesis, characterization and investigation of photoinduced properties of Re(I) tricarbonyls compounds coordinated with polypyridine and naphthalimidic ligands

• Grant number: 22/16402-0
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: October 01, 2023
• End date: January 31, 2028
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal Investigator: Sofia Nikolaou
• Grantee: Luis Guilherme Alves do Nascimento
• Host Institution: Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto (FFCLRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

This project proposes the investigation of the chemical, photochemical and photophysical properties of some polypyridine compounds of rhenium(I) aiming their application as luminescent probes or in devices for energy conversion. The luminescent complexes fac-[Re(CO)3(NN)(NI-X)]PF6, where NN = 1,10-phenanthroline (phen) or dipyrido[3,2-a:2',3'-c] phenazine (dppz), and NI-X = N-(4-pyridyl)-1,8-naphthalimide; 4-amino-N-(4-pyridyl)-1,8-naphthalimide or 4-nitro-N-(4-pyridyl)-1,8-naphthalimide will be prepared and characterized. The union of different ligands that provide emissive charge transfer levels will allow the modulation of the properties of the new complexes. The goal is to observe energetically different excited states with potentially long and modulable lifetimes. In addition, the choice of substituents in the naphthalimides was made according to the different acceptor (nitro group) or donor (amino group) characteristics of electron density, which should allow direct modulation of the absorption and emission energy of the complexes. The ligands and complexes will be prepared from unpublished synthetic routes, based on procedures developed in our laboratory and with the collaboration of Prof. André S. Polo, professor at the Center for Natural and Human Sciences at UFABC. They will be characterized by electronic spectroscopy of absorption and emission, vibrational in the infrared region and NMR (1H and 13C), elemental analysis and cyclic voltammetry. Complementary techniques, such as mass spectrometry and differential pulse voltammetry, can be used as needed. It should be noted that the use of these ligands can result in the formation of supramolecular structures, both in solution and in solid state, due to their possible À stacking, which will also be investigated to assess whether this structure is better for the desired purposes. Finally, considering the characteristics of the chosen ligands and literature precedents, confocal spectroscopy experiments will be carried out to verify the possibility of using these complexes as luminescent probes in biological media. The prepared compounds will also have their characteristics evaluated for use in energy conversion devices and, if appropriate, devices for this purpose will be tested. (AU)