Post‐Synthetic Modification Unlocks a 2D‐to‐3D Switch in MOF Breathing Response: A Single‐Crystal‐Diffraction Mapping Study

Abstract

Post‐synthetic modification (PSM) of the interpenetrated diamondoid metal–organic framework (Me2NH2)[In(BDC‐NH2)2] (BDC‐NH2=aminobenzenedicarboxylate) SHF‐61 proceeds quantitatively in a single‐crystal‐to‐single‐crystal manner to yield the acetamide derivative (Me2NH2)[In(BDC‐NHC(O)Me)2] SHF‐62. Continuous breathing behaviour during activation/desolvation is retained upon PSM, but pore closing now leads to ring‐flipping to avert steric clash of amide methyl groups of the modified ligands. This triggers a reduction in the amplitude of the breathing deformation in the two dimensions associated with pore diameter, but a large increase in the third dimension associated with pore length. The MOF is thereby converted from predominantly 2D breathing (in SHF‐61) to a distinctly 3D breathing motion (in SHF‐62) indicating a decoupling of the pore‐width and pore‐length breathing motions. These breathing motions have been mapped by a series of single‐crystal diffraction studies.

Characterization of an unanticipated indium-sulfur metallocycle complex

“…Furthermore, the In(III) state is thermodynamically favoured so the number of reported In(II) compounds is relatively few [19]. Indeed, in this study we were originally using In(III) nitrate as a precursor in reactions intended to make metal–organic frameworks (MOFs), an area of growing interest [20–26], and were surprised to find an In(II) product formed. The synthesis processes of MOFs is an area of particular interest, but relatively little consideration has been given to identifying the side-products when phase-pure materials are not formed [27,28].…”