1D Coordination Polymers Constructed from Pyridine-2,6-Dicarboxamide Ligands Showing Selective and Recyclable Adsorption toward Methanol Vapor
Hua-Qing Tian, Tao Jiang, Hong-Lu Shen, Chao Huang, Bi‐Xue Zhu
Abstract
Two helical ligands ( L 1 and L 2 ) containing a pyridine-2,6-dicarboxamide skeleton were synthesized, and the crystal structures indicated racemic configurations with equal amounts of P - and M -helicity. Eight one-dimensional coordination polymers (CPs), {[Zn L 1 Cl 2 ]·2CH 3 OH} n ( 1 ), [Hg L 1 I 2 ] n ( 2 ), {[Ag L 1 NO 3 ]·CHCl 3 } n ( 3 ), {[Cd( L 1 ) 2 Cl 2 ]·2DMF} n ( 4 ), {[Co( L 1 ) 2 Cl 2 ]·2DMF} n ( 5 ), {[Zn L 2 I 2 ]·2DMF·H 2 O} n ( 6 ), [Hg L 2 Cl 2 ] n ( 7 ), and {[Hg 2 ( L 2 ) 2 Br 4 ]·2CH 3 OH} n ( 8 ), were synthesized from the reaction of the two ligands with a series of transition metal ions. The crystal structures showed that the chiral self-assembly process of these ligands resulted in homochiral complexes (CP 1, 3, and 6 ), heterochiral complexes (CP 2, 4, 5, and 7 ), or the coexistence of homochiral and heterochiral complexes (CP 8 ). The gas adsorption/desorption experiments were investigated at room temperature, which showed that all the CPs exhibited good selective adsorption capacities (24.6–62.5 cm 3 /g) toward methanol vapor over other gas. Furthermore, CP 3, 5, and 6 were selected for the recyclable methanol vapor adsorption experiments, and the results showed that all three CPs can be recycled as good adsorbents for methanol vapor.