Polyrotaxane-like and Interpenetrating Metal−Organic Frameworks (MOFs) Constructed from Biphenyl-4,4′-Dicarboxylate and Bis(imidazole) Ligand

The paper presents three interesting entanglement systems, including two polyrotaxane-like and one interpenetrating frameworks, namely, [Co(L¹)(bpdc)] (1), [Co(L²)(bpdc)] (2), and [Co(L³)1.5(bpdc)(H₂O)]·(L³) (3), constructed from biphenyl-4,4′-dicarboxylate and bis(imidazole) ligands (L¹ = 1,6-bis(imidazol-1-yl)-hexane, and rods that are interlaced in a parallel fashion to result in 2D → 2D polyrotaxane-like motifs (L² = 1,4-bis(imidazol-1-ylmethyl)benzene and L³ = 1,4-bis(1-imidazolyl)-benzene)). Both compounds 1 and 2 contain loops. Compound 3 represents the first example of a triply interpenetrated 5-connected 4⁴6⁶ topology network.