A novel chemiluminescence from the reaction of singlet oxygen with β-diketonates of europium(iii), neodymium(iii) and ytterbium(iii)

Abstract

Decomposition of 1,4-dimethylnaphthalene endoperoxide, which is the source of singlet oxygen, in the presence of β-diketonates of europium(III), neodymium(III) and ytterbium(III) is accompanied by bright chemiluminescence (CL) in visible and near infra-red spectral region due to characteristic emission from the lanthanides at λ_max = 615 and 710 nm (⁵D₀→⁷F₂ and ⁵D₀→⁷F₄ transitions of Eu³⁺), 900 nm (⁴F_3/2→⁴I_9/2 transition of Nd³⁺) and 1000 nm (²F_5/2→²F_7/2 transition of Yb³⁺). Singlet oxygen is the key intermediate responsible for the observed CL, which is presumably generated by the reaction of ¹O₂ with ligands of the complexes. The CL phenomenon discovered herein paves the way towards the development of lanthanide-based CL probe for ¹O₂.