An octanuclear [Co(II)2–Co(III)2]2 interlocked grid—example of an inorganic [2]catenane

An oxalic dihydrazide based flexible polydentate amidrazone ligand undergoes spontaneous [2 × 2] grid assembly, followed by partial disassembly, and then reassembly in the presence of Co(NO3)2·6H2O and NH4(NCS) to form a unique octanuclear [Co(II)2–Co(III)2]2 interlocked, single braided 4 + 4 [2]catenane.