Cubic Polyoxometalate−Organic Molecular Cage

Tris(hydroxymethyl)aminomethane (Tris) was successfully grafted onto the surface of a Ni6-substituted polyoxotungstate formed in situ to further generate a three-connected polyoxometalate building block. The cooperative assembly of Tris functionalized three-connected building blocks and rigid 1,3,5-benzenetricarboxylate gave rise to an unprecedented cubic polyoxometalate−organic molecular cage with high thermal and hydrothermal stability.