Nanoscale chiral rod-like molecular triads assembled from achiral polyoxometalates.

The assembly of two achiral POMs of Lindqvist and Anderson through strong covalent linkages, using bifunctional TRIS with a rotatable C-N single bond, gives two nanoscale rod-like chiral molecular triads with C(2) symmetry, the chirality of which were confirmed by the single crystal X-ray diffraction analyses and solid CD spectroscopy measurements. The enantiopure crystals of these compounds have been obtained by spontaneous resolution upon crystallization in the absence of any chiral source. The present work opens a way to make chiral nanostructures from achiral polyoxoanions, which may have potential applications in asymmetric catalysis, NLO, and ferroelectric materials.