An expanded MIL-53-type coordination polymer with a reactive pendant ligand

A coordination polymer with a structure isoreticular to MIL-53, but containing a divalent metal cation (Co2+ or Mg2+) and a coordinating 4-styrylpyridine-N-oxide ligand, crystallises under solvothermal conditions; the pendant ligand can be brominated, with evidence from powder X-ray diffraction, element mapping and Br-81 solid-state NMR for this post-synthesis modification.