Metal–organic frameworks of p-hydroxybenzoic acid: synthesis, structure and ring opening polymerization capability

Abstract

Two new, isostructural, metal–organic frameworks {[Co(O₂CC₆H₄O)(DMF)]₂}_n and {[Mn(O₂CC₆H₄O)(DMF)]₂}_n have been synthesised and structurally characterized. Use of p-hydroxybenzoic acid resulted in a three-dimensional MOF featuring a linker with a carboxylic group and a para-hydroxyl group. Ring opening polymerization of ε-caprolactone and δ-valerolactone has been performed using these MOFs as catalysts, and results compared with the known zinc MOF Zn(O₂CC₆H₄O). The resulting products are predominantly cyclic polymers. The manganese and zinc MOFs exhibit significant recyclability during ring opening polymerization.