Molecular engineered rhenium(i) carbonyl complexes to promote photoisomerization of coordinated stilbene-like ligands in the visible region

Abstract

Novel fac-[Re(CO)₃(dmcb)(trans-stpyR)]⁺ complexes, dmcb = 4,4′-dimethoxycarbonyl-2,2′-bipyridine, have been judiciously engineered to absorb at lower energies and sensitize trans-4-styrylpyridine (trans-stpy) or trans-4-(4-cyano)styrylpyridine (trans-stpyCN) photoisomerizable ligands up to 436 nm of irradiation. Moreover, these complexes exhibit remarkable photoreversibility, in particular fac-[Re(CO)₃(dmcb)(trans-stpyCN)]⁺ (Φ^{255 nm}_cis→trans = 0.26 ± 0.02). Their distinct and noteworthy photochemical and photophysical behavior are described in this work. The main emphasis of this study is that the complexes efficiently sensitize stilbene-like ligand isomerization toward use in potential solar device applications.