Metal-Dependent Phase Selection in Coordination Polymers Derived from a C2v-Symmetric Tricarboxylate

Reacting biphenyl-3,4',5-tricarboxylic acid (H3BHTC) with the appropriate metal salt yields the microporous coordination polymers (MCPs) Mn-3(BHTC)(2) (1), Mg-3(BHTC)(2) (2), and Co-3(BHTC)(2) (3) containing hourglass metal clusters. The addition of Cu to reactions with Co-II, Fe-III, or Mn-II leads to the formation of heterobimetallic UMCM-150 isostructural analogues Co1Cu2(BHTC)(2) (4), Fe1Cu2(BHTC)(2) (5), and Mn1Cu2(BHTC)(2) (6) containing both paddlewheel and trinuclear metal clusters. X-ray diffraction analysis of the crystals of the heterobimetallic MCPs suggests that Cu on the trinuclear site of UMCM-150 was replaced by the other metal, whereas Cu in paddlewheel sites remains unchanged. N-2 sorption isotherms were measured for the mixed-metal UMCM-150 analogues, and it was confirmed that there is no structural collapse after the metal replacement.