A new chelate ligand designed for the uranyl ion

The ligand L, L = N,N′-di(2-hydroxy-4,6-di-tert-butyl-benzyl)imidazolidine, reacts with UO22+, in organic and aqueous media, to yield a complex of UO22+ with the ligand L′, L′ = N,N′-di(2-hydroxy-4,6-di-tert-butyl-benzyl)-N-2-hydroxylethane–ethylenediamine. The opening of the imidazolidinic ring is a base catalyzed process which is induced by the uranyl ions. The complex UO22+L′ has two reasonably strong absorption bands at 390 and 490 nm. Thus L can be used to determine quantitatively the concentration of UO22+ in protic and aprotic media.