Study of the mechanism of photodimerization reaction of decarboxyranelate acid through ultrafast spectroscopy

• Grant number: 23/08718-0
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate (Direct)
• Start date: January 05, 2024
• End date: January 04, 2025
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Henrique Eisi Toma
• Grantee: Luca Michael Sihn
• Supervisor: Jacinto de Paiva Sá
• Host Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: Uppsala University (UU), Sweden
• Associated to the scholarship: 18/25974-1 - Photochemestry, photophyisics and photoeletrochemestry of the ranelate ion, BP.DD

Abstract

Decarboxyranelic acid, a compound derived from Strontium Ranelate, features a thiophenic ring structure from which carboxylic and amino-carboxylic arms, resembling EDTA, as well as a nitrile group, emerge. Under acidic conditions and UV radiation, it undergoes dimerization at carbon 2, giving rise to a blue product called RanB. This reaction requires an acidic medium, oxygen, and light to occur. The present project aims to investigate the photochemical process through time-resolved ultrafast spectroscopy. To accomplish this, the photochemical process will be monitored using Transient Absorption Spectroscopy (TAS) and Transient Infrared Absorption Spectroscopy (TIRAS). Both techniques enable time-resolved analyses on the femto-second scale, allowing for the study of significant processes in this reaction, such as proton transfer, radical formation, and intermediate formation. This reaction and the effects of the main factors will be studied, observing which reaction processes are affected in the presence and absence of O2, light and acidic medium. In addition to being essential techniques for resolving the photochemistry of this reaction, the knowledge of both TAS and TIRAS is of utmost importance for studying photoactive systems. Bringing this knowledge to the laboratory will contribute to significant advancements in research conducted by the group in the field of photonics and photocatalysis. However, in addition to bringing knowledge to the laboratory, the BEPE program will facilitate a connection with Professor Jacinto Sa's research group, enabling potential partnerships for future projects. (AU)