An indirect generation of 1D MII-2,5-dihydroxybenzoquinone coordination polymers, their structural rearrangements and generation of materials with a high affinity for H2, CO2 and CH4

Article abstract of DOI:10.1039/c5dt04095g

A series of solid-state structural transformations are found to accompany desolvation of relatively simple coordination polymers to yield materials that exhibit unexpected gas sorbing properties. Reaction of 1,2,4,5-tetrahydroxybenzene with M^II salts (M = Mg, or Zn) in an alcohol/water solution in the presence of air affords cis-M^II(C₆H₂O₄^-II)(H₂O)₂·2H₂O·xROH, (M = Mg, or Zn), crankshaft-like chains in which the absolute configurations of the chiral metal centres follow the pattern ?Δ Δ Λ Λ Δ Δ Λ Λ?, and are hydrogen bonded together to generate spacious channels. When crystals of the crankshaft chain are air dried the crystals undergo a single crystal-to-powder rearrangement to form linear trans-M^II(C₆H₂O₄^-II)(H₂O)₂ chains. Further dehydration yields microporous solids that reversibly sorb H₂, CH₄ and CO₂ with high sorption enthalpies.