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 LnIII. 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 EuIII center.