Competition between coordination and hydrogen bonding in networks constructed using dipyridyl-1H-pyrazole ligands
RIS ID
38450
Abstract
The reaction between zinc(ii) acetate and 3,5-di(4-pyridyl)-1H-pyrazole (HL1) is crucially dependent on the solvent, with products based on different architectures formed in DMF, methanol and water. When the reaction is undertaken in DMF, the product is [Zn3(OAc)6(HL 1)4] 1, in which Zn(OAc)2 centres link Zn 2(OAc)4(HL1)4 units into double-stranded zig-zag chains. Each chain is 'broken' after every fourth HL1 ligand, though the links between the chains ensure a coordination polymer is formed. The reaction in methanol produces [Zn(OAc) 2(HL1)].0.5MeOH 2 which also contains double-stranded chains, though in this case both chains are continuous. The hydrothermal reaction gives [Zn(OAc)2(HL1) 2].H2O 3, which contains discrete zinc complex molecules that are linked into double-stranded chains through hydrogen bonds. Zinc(ii) chloride reacts with HL1 to form [ZnCl2(L 1)] 4. The structure of 4 consists of chains that are cross-linked into sheets by N-HCl hydrogen bonds. The nitrates of zinc(ii), cobalt(ii) and nickel(ii) react with 3,5-di(3-pyridyl)-1H-pyrazole (HL 2) to form [M(MeOH)4(HL2)2](NO 3)2.2H2O (5, M = Zn; 6, M = Co; 7, M = Ni). These isostructural compounds contain discrete cations that are linked into double-stranded chains by O-HN hydrogen bonds, with further hydrogen bonds connecting these into sheets. The structures of 1-3 and 5-7 all contain double-stranded chains, with both bridging ligands and hydrogen bonds linking individual chains into pairs. Copyright 2011 The Royal Society of Chemistry
Publication Details
Burrows, A. D., Kelly, D. J., Haja Mohideen, M. Infas., Mahon, M. F., Pop, V. M. & Richardson, C. (2011). Competition between coordination and hydrogen bonding in networks constructed using dipyridyl-1H-pyrazole ligands. CrystEngComm, 13 (5), 1676-1682.