Hetero Bi-Paddle-Wheel Coordination Networks: A New Synthetic Route to Rh-Containing Metal–Organic Frameworks

We have successfully synthesized rhodium-containing MOFs with 1:1 abundance ratios of paddle-wheel units of Rh2 and Cu2/Zn2, i.e., [Rh2M2(1,4-bdc)4]·nSolvent (M = Cu: RhCu-DMF, RhCu-EtOH; M = Zn: RhZn-DMF; 1,4-bdc: 1,4-benzenedicarboxylate) by a novel synthetic method involving assembly of discrete paddle-wheel dirhodium(II) tetra(1,4-benzenedicarboxylate) with Cu2+ or Zn2+ ions. The diffraction patterns of these complexes were very similar to the predicted and experimental XRPD patterns reported for [Cu2(1,4-bdc)2]. This result indicates that this method enables the incorporation of coordinatively unsaturated noble-metal sites for the many reported MOFs with multi-carboxy ligands and paddle-wheel nodes.