Metal-Organic Framework Derived Phytate-Iron for Efficient Synthesis of 2-Arylbenzoxazole via Hydrogen Transfer Strategy

Recently, metal-organic framework (MOF) and its derivatives showed great application potential in catalysis.ZIF-L-Co@phytate-iron (ZIF-L-Co@PA-Fe) heterogeneous MOF derivatives were synthesized by a facile surface engineering method.Phytic acid functionalized ZIF-L-Co (ZIF-L-Co@PA) was firstly prepared through organic ligand exchange of phytic acid (PA).Then, ZIF-L-Co@PA-Fe with unique heterostructure was prepared via coordination occurred between Fe 3 ＋ and ligands.Benefiting from the greatly modify metal-ligand interactions, the as-designed ZIF-L-Co@PA-Fe hybrids exhibited excellent catalytic activities toward the hydrogen transfer reactions.2-Substituted benzoxazole derivatives were successfully synthesized via transfer hydrogenative annulation of o-nitrophenol with alcohols catalyzed by ZIF-L-Co@PA-Fe under solvent-free conditions.No additional additives, such as oxidants, reductants or bases were required for this reaction.Moreover, ZIF-L-Co@PA-Fe coordination complex showed excellent reusability and could be recycled up to five times without obvious decline in its catalytic activity.This work may provide effective guidance for optimizing the catalytic performance of other series of MOF derivatives.