Contrasting solvent and capping ligand effects directing the photochemistry of uranyl(VI) Schiff base complexes.
Photolysis of the uranyl(VI) Schiff base complex UO2(tBu4-salphen)(THF) (1a) with cobaltocene in THF affords [Cp2Co][UO2(tBu4-salphen)(OH)] (2) in high yield while irradiation in toluene yields no reaction. Electronic emission spectra of 1a reveal a large Stokes' shift in toluene similar to that observed in the free ligand, while in THF the structural rearrangement responsible for this shift is blocked. Instead, the ligand-centered excited state is redirected to the uranyl(VI) center by way of energy transfer, thus generating 2 from the intramolecular activation of a coordinated THF molecule.
Vaughn
Anthony E
AE
Department of Chemistry, University of Missouri-Columbia, 601 S. College Avenue, Columbia, Missouri 65211, USA.
Bassil
Daniel B
DB
Barnes
Charles L
CL
Tucker
Sheryl A
SA
Duval
Paul B
PB