A Noninterpenetrated Metal-Organic Framework Built from an Enlarged Tetracarboxylic Acid for Small Hydrocarbon Separation

A novel noninterpenetrated metal organic framework [Cu2L-(H2O)(2)]f center dot(DMA)(18)center dot(H2O)(19) (ZJU-31, ZJU = Zhejiang University; H4L = 5', 5''''- (2,5-dimethoxy4,4-phenylene)bis [1,1' : 3',1 '' -t erphenyl] -4,4 ''-dicarboxylic acid; DMA = N,N-dimethylacetamide) has been synthesized and structurally characterized from an expanded organic linker. Interestingly, although the new linker is larger than the developed one for the construction of ZJU-30 with a doubly interpenetrated structure, the incorporation of a 1,4-dimethoxyphenyl group into the new linker enforces the formation of noninterpenetrated ZJU-31. Accordingly, the activated ZJU-31a shows a much higher porosity with a BET surface area of 1115 m(2)/g than ZTU-30a of 228 m(2)/g. ZJU-31a exhibits highly selective separation of C-2 hydrocarbons over C, methane at room temperature.