Proton-controlled photoisomerization: rhenium(i) tricarbonyl bipyridine linked to amine or azacrown ether groups by a styryl pyridine bridging ligandElectronic supplementary information (ESI) available: UV/vis absorption spectra of 2. See http://www.rsc.org/suppdata/cc/b0/b005889k/

Abstract

Complexes in which fac-(bpy)Re(CO)₃ is linked by a styryl pyridine to an amine or an azacrown ether show no photoreaction in acetonitrile in the absence of acid, but they photoisomerize readily at the stilbene-like bridging ligand when the terminal amine or azacrown ether group is protonated because an intramolecular energy-transfer mechanism becomes available.