Synthesis, photophysical, photochemical and electrochemical properties of rhenium(I) diimine complexes with photoisomerizable pyridyl-azo, -ethenyl or -ethyl ligands

Abstract

A series of rhenium(I) diimine complexes with pyridyl-azo, -ethenyl or -ethyl type ligands, [Re(CO)₃(N–N)L]ClO₄ and [{Re(CO)₃(N–N)}₂L′][ClO₄]₂ {N–N = 2,2′-bipyridine (bpy), 1,10-phenanthroline (phen); L = 4-phenylazopyridine (PHAZO), 4-styrylpyridine (STYPY), [2-(4-pyridyl)ethyl]benzene (PEB), 4-(4-nitrostyryl)pyridine (NSP); L′ = 4,4′-azopyridine (AZO), 1,4-bis[2-(4-pyridyl)ethenyl]benzene (BPENB), 1,4-bis[2-(4-pyridyl)ethyl]benzene (BPEB)} have been synthesized and their photophysical properties studied. The quantum yields for the photoinduced isomerization of the complexes [Re(CO)₃(bpy)(NSP)]⁺ and [Re(CO)₃(phen)(NSP)]⁺ have been determined.