CRYSTAL STRUCTURE AND PHOTOCHEMISTRY OF BIS(BIPYRIDINE)-BIS(4-AMINOPYRIDINE)RUTHENIUM(II)

Abstract

The title complex, cis-[Ru(bpy)₂(4-apy)₂] (ClO₄)₂CH₃CN (where bpy = 2,2′-bipyridine, 4-apy = 4-aminopyridine), has been synthesized and characterized. An X-ray crystal structure determination established that the coordination geometry about ruthenium(II) is distorted octahedral with four nitrogen atoms from the two bpy molecules and two pyridine nitrogen atoms from apy coordinate. Time-resolved and steady-state luminescence spectra show that the emission wavelength, quantum yield and the luminescence lifetime are quite similar to those of corresponding complexes with pyridine instead of apy, which indicates that the amino group of the apy cannot quench the luminescence. Electrochemistry in CH₃CN is consistent with this result.

The complex crystallines in the monoclinic space group, P2₁/n with cell parameters a = 10.585(2), b = 11.615(2), c = 15.992(3) Å, β = 99.76(3)° and Z = 4. The structure was refined by full-matrix least-squares methods to R = 0.071 and R_w = 0.093 for 4625 reflections having F > 6σ(F).

Key Words:

• Ruthenium(II)
• crystal structure
• time-resolved luminescence