Nanoscale ensembles using building blocks inspired by the [FeFe]-hydrogenase active site

The hydrogenase model [Fe2(S2C3H6)(CN)2(CO)4]2− was employed as a molecular tecton for the construction of supramolecular aggregates. IR spectroscopy indicated that cyanide bridged aggregates are formed when [Fe2(S2C3H6)(CN)2(CO)4]2− was treated with Lewis acids such as Zn(tetraphenylporphyrinate), [Cu(NCMe)(2,2′-bipyridine)]PF6 and [Cu(NCMe)4]PF6. Condensation of [Fe2(S2C3H6)(CN)2(CO)4]2− with the tritopic Lewis acid [Cp∗Rh]2+ afforded the novel expanded tetrahedron cage, {[Fe2(S2C3H6)(CN)2(CO)4]6[Cp∗Rh]4}4−. The tetrahedron cage was characterized crystallographically as the PPN salt.