Structure-directing roles of polycarboxylate anions in the formation of Ag(i) coordination polymers with mixed ligands

Abstract

Hydrothermal reactions of bis-pyridyl-bis-amide with polycarboxylic acid and Ag(I) salt afforded {[Ag(L¹)][HCDDC]}_n [L¹ = N,N′-di(4-methylpyridyl)oxamide; H₂CDDC = 7-carboxy-1,3-dioxo-1,3-dihydrobenzo[de]isochromene-6-carboxylic acid], 1, {[Ag(L¹)][1,4-HNDC]·2H₂O}_n (1,4-H₂NDC = 1,4-naphthalenedicarboxylic acid), 2, [Ag(1,2,4,5-H₂BTEC)_0.5(L¹)_0.5]_n (1,2,4,5-H₄BTC = 1,2,4,5-benzenetetracarboxylic acid), 3, {[Ag(L¹)(H₂O)][1,2,4,5-H₃CTC]·H₂O}_n (1,2,4,5-H₄CTC = 1,2,4,5-cyclohexanetetracarboxylic acid), 4, {[Ag(L²)][1,4-HNDC]·H₂O}_n [L² = N,N′-di(3-pyridyl)oxamide; 1,4-H₂NDC = 1,4-naphthalenedicarboxylic acid], 5, {[Ag₂(L¹)₂][1,2,4-HBTC]·2H₂O}_n (1,2,4-H₃BTC = 1,2,4-benzenetricarboxylic acid), 6, {[Ag₂(L¹)_1.5][(1,3,5-HBTC)(H₂O)]·2H₂O}_n (1,3,5-H₃BTC = 1,3,5-benzenetricarboxylic acid), 7, {[Ag(L¹)_0.5][(1,3,5-H₂BTC)]}_n, 8, and {[Ag₅(1,3,5-HBTC)(1,3,5-BTC)(L¹)₂]·5H₂O}_n, 9, which have been structurally identified by using single-crystal X-ray diffraction. Complexes 1, 2, 4, 5 and 6 are 1D zigzag chains and 8 forms a 1D looped chain, whereas 3 features a 3D framework with the fsh topology, 7 reveals a linear tetranuclear molecule and 9 adopts a 3-fold interpenetrated 3D framework with the sra topology. The roles of the polycarboxylate anions in determining the structural diversity of these Ag(I) complexes are evaluated.