Boronic acid derivatized lanthanide–polyoxometalates with novel B–OH–Ln and B–O–Nb bridges

Abstract

Three new boronic acid derivatized lanthanide–polyoxometalates (BA-Ln–POMs) were synthesized, in which boronic acids served as bi- or tri-dentate ligands and exhibited interesting coordination ability towards POMs and Ln^III. The pH was found to be crucial in controlling the coordination modes of boronic acid and the formation of B–O–Ln and B–O–Nb bridges. Compared with the boronic acid-free Ln–POM, a longer lifetime was observed for compound 2Eu due to the coordination of boronic acids to the Eu^III center.