Chiral two-dimensional metal-organic frameworks based on Zn(salen) ligands: subcomponent self-assembly and circularly polarised luminescence

A pair of chiral metal-organic frameworks based on enantiomers of chiral Zn(salen) ligands has been successfully obtained by solvothermal subcomponent self-assembly. Both chiral MOFs were characterized by infrared spectroscopy, UV-vis absorption spectroscopy, thermogravimetric analysis, and single-crystal/powder X-ray diffraction. They crystallize in the chiral space group I222 and possess an extended 2D network with a sql topology. Moreover, these MOFs exhibit circularly polarized luminescence (CPL) with a dissymmetry factor of about 3.7 x 10(-3). This work provides a simple strategy to make CPL-active MOF materials based on salen ligands.