Photogeneration of Manganese(III) from Luminescent Manganese(II) Complexes with Thiacalixarene Ligands: Synthesis, Structures and Photophysical Properties


Photogeneration of Manganese(III) from Luminescent Manganese(II) Complexes with Thiacalixarene Ligands: Synthesis, Structures and Photophysical Properties

O'Toole, N.; Lecourt, C.; Suffren, Y.; Hauser, A.; Khrouz, L.; Jeanneau, E.; Brioude, A.; Luneau, D.; Desroches, C.

The photophysical properties of the compound [(ThiaSO₂)(MnII)₂(DMF)₄(H₂O)₂] (2), ThiaSO₂ = p-tert-butylsulfonylcalix[4]arene, are presented and compared to the ones of [(ThiaSO₂)₂(MnII)₄F]K (1). The orange luminescence of 2 is attributed, as for 1, to the MnII centred ⁴T₁→⁶A₁ transition and shows, for this type of complex, the weak influence of the Mn²⁺ coordination and ThiaSO₂ conformation on this luminescence, the temperature and pressure dependence and quenching bymolecular dioxygen of which are reported for 2. The latter is attributed to energy transfer from the ⁴T₁ state exciting dioxygen to its ⁱΣ⁺ᵍ state and is responsible for the photosynthesis of the [(ThiaSO₂)(MnIII)(DMF)₂]Na (3) complex in DMF solution from 1 or 2. This reaction was studied by UV/Visible and EPR spectroscopy. The molecular structure and EPR spectroscopy of 3 are also presented.

Keywords: Thiacalixarene; Luminescence; Photooxidation; Manganese

Permalink: https://www.hzdr.de/publications/Publ-28984
Publ.-Id: 28984