A chiral metal-organic cage [Fe4L6](ClO4)8 used for capillary gas chromatographic separations.

Metal-organic cages (MOCs), as a promising class of crystalline porous materials with well-defined cavities, have attracted wide attention due to their multifarious potential applications in gas storage, host-guest chemistry, molecular recognition, separation, catalysis, sensing, and drug delivery and so on. Herein, we report that a chiral MOC [Fe4L6](ClO4)8 coated capillary column was fabricated for high-resolution gas chromatographic separation of various analytes, including n-alkanes, n-alcohols, positional isomers, aromatic hydrocarbon mixture, especially for racemic compounds. A series of racemic compounds such as alcohols, epoxides, aldehydes, ketones, ethers, esters, alkenes, sulfoxides and amino acid derivatives could be well separated on the [Fe4L6](ClO4)8 coated capillary column with high enantioselectivity and good reproducibility. Comparing the chiral resolution ability of the MOC [Fe4L6](ClO4)8 coated column with the commercial β-DEX 120 column and the porous organic cage (POC) CC10 coated column, the chiral MOC column can be complementary to the two different types of columns. The results show that the chiral MOC [Fe4L6](ClO4)8 exhibited excellent separation performance toward a wide range of organic compounds, which will be very attractive as a new chiral separation media and has potential application prospects in separation science.