Supramolecular Aggregation Control in Polyoxometalates Covalently Functionalized with Oligoaromatic Groups

Abstract

CLICK-chemistry has become a universal route to covalently link organic molecules functionalized with azides and alkynes, respectively. Here, we report how CLICKchemistry can be used to attach oligoaromatic organic moieties to Dawson-type polyoxometalates. In step one, the lacunary Dawson anion [α 2 -P 2 W 17 O 61 ] 6À is functionalized with phosphonate anchors featuring peripheral azide groups. In step two, this organic-inorganic hybrid undergoes micro-wave-assisted CLICK coupling. We demonstrate the versatility of this route to access a series of Dawson anions covalently functionalized with oligoaromatic groups. The supramolecular chemistry and aggregation of these systems in solution is explored, and we report distinct changes in charge-transfer behavior depending on the size of the oligoaromatic πsystem.