ABSTRACT
A tetratopic bis(diphenylamino)anthraquinone linker is presented, and its physicochemical properties are evaluated. The linker is shown to successfully coordinate alkaline earth metals leading to four new reported metal-organic frameworks (MOFs), which have been fully characterized, including single-crystal X-ray diffraction. The physicochemical and emissive properties of the MOF materials are investigated and compared to those of the uncoordinated ligand. Finally, the catalytic behavior of the ligand and the MOF materials toward the photooxidation of sulfides is described.
ABSTRACT
A dipyridyl-substituted anthraquinone (2,6-di(pyridin-4-yl)-9,10-anthraquinone, DPAq) was incorporated as a redox-active linker molecule into crystalline coordination networks. The oxidation state of the organic linker can be selectively controlled prior to framework formation and furthermore be maintained in the solid state. Hydrogen bonding is identified to be a substantial stabilization factor. Additionally, it is shown that the anthraquinone-anthrahydroquinone redox pair can be switched reversibly even after incorporation in the solid state by a thermal treatment/soaking procedure-going along with the formation of hydrogen peroxide from molecular oxygen (air) during the oxidation process.