Synthesis, structure, and metalation of two new highly porous zirconium metal-organic frameworks

Abstract

Three new metal-organic frameworks [MOF-525, Zr 6O 4(OH) 4(TCPP-H 2) 3; MOF-535, Zr 6O 4(OH) 4(XF) 3; MOF-545, Zr 6O 8(H 2O) 8(TCPP-H 2) 2, where porphyrin H 4-TCPP-H 2 = (C 48H 24O 8N 4) and cruciform H 4-XF = (C 42O 8H 22)] based on two new topologies, ftw and csq, have been synthesized and structurally characterized. MOF-525 and -535 are composed of Zr 6O 4(OH) 4 cuboctahedral units linked by either porphyrin (MOF-525) or cruciform (MOF-535). Another zirconium-containing unit, Zr 6O 8(H 2O) 8, is linked by porphyrin to give the MOF-545 structure. The structure of MOF-525 was obtained by analysis of powder X-ray diffraction data. The structures of MOF-535 and -545 were resolved from synchrotron single-crystal data. MOF-525, -535, and -545 have Brunauer-Emmett-Teller surface areas of 2620, 1120, and 2260 m 2/g, respectively. In addition to their large surface areas, both porphyrin-containing MOFs are exceptionally chemically stable, maintaining their structures under aqueous and organic conditions. MOF-525 and -545 were metalated with iron(III) and copper(II) to yield the metalated analogues without losing their high surface area and chemical stability. © 2012 American Chemical Society.