Cucurbituril-Shaped Cd 18 (triazolate) 12 Unit-Based Metal-Organic Framework Exhibiting an C 2 H 2 /CO 2 Separation Ability.

Herein, a metal-organic framework (MOF), {[(Me 2 NH 2 ) 4 ][Cd(H 2 O) 6 ][Cd 18 (TrZ) 12 (TPD) 15 (DMF) 6 ]} n (denoted as JXNU-18, TrZ = triazolate), constructed from the unique cucurbituril-shaped Cd 18 (TrZ) 12 secondary building units bridged by 2,5-thiophenedicarboxylic (TPD 2- ) ligands, is presented. The formation of the cucurbituril-shaped Cd 18 (TrZ) 12 unit is unprecedented, demonstrating the geometric compatibility of the organic linkers and the coordination configurations of the cadmium atoms. Each Cd 18 (TrZ) 12 unit is connected to eight neighboring Cd 18 (TrZ) 12 units through 30 TPD 2- linkers, affording the three-dimensional structure of JXNU-18. More interesting is that JXNU-18 displays an efficient C 2 H 2 /CO 2 separation ability, as revealed by the gas adsorption experiments and dynamic gas breakthrough experiments, which afford insights into the potential applications of JXNU-18 in gas separation. The tubular pores composed of two Cd 18 (TrZ) 12 units bridged by six 2,5-thiophenedicarboxylic linkers provide the suitable pore space for C 2 H 2 trapping, as unveiled by computational simulations.