Exploring Photophysical Properties and Sensitivity to Oxygen in Anisolyl-Picolinate Antenna Conjugated to Azamacrocycles
Lucile Bridou, Loëza Collobert, Kyangwi P. Malikidogo, Salauat Kiraev, Maher Hojorat, Nadège Hamon, Anh Thy Bui, François Riobé, Akos Banyasz, Maryline Beyler, Raphaël Tripier, Olivier Sénèque, Olivier Maury
Inorg. Chem., 2025, 64, 27, 13635–13646, DOI:10.1021/acs.inorgchem.5c00436, hal-05162444

An anisolyl-picolinate antenna grafted onto different macrocyclic ligands such as tacn, pyclen, or cyclen renders the resulting terbium(III) complexes highly sensitive to oxygen in aqueous solutions, enabling the design of ratiometric or lifetime-based molecular sensors. The underlying sensitization mechanism was investigated using analogous gadolinium(III) complexes, and the oxygen sensitivity was studied using transient absorption spectroscopy. The antenna-based triplet lifetime increased by up to 900-fold upon degassing, underscoring the role of the ligand excited states in designing highly sensitive oxygen probes.