Resonance raman spectra of molecular oxygen adducts of Co(salen) and its derivatives in solution

Abstract

Resonance Raman spectra of the molecular oxygen adducts of six Co(salen) derivatives have been measured in CH 2Cl 2 or CHCl 3 containing pyridine using the mini-bulb method (∼−80°C, ∼4 atm O 2 pressure). These adducts exhibit the O 2 and CoO stretching bands at 1146−1143 and 530−515 cm −1, respectively. Although the former is insensitive to the nature of the in-plane ligand, the latter is sensitive to the geometry of the CoN 2O 2 core (steric effect) and the degree of π-conjugation over the entire chelate ring (electronic effect).