Study on the effects of structure of second ligands and [CuCl4]2- configuration on channel framework between layers

The designed and synthesized protonated ligands, N,N,N',N'-tetra-(p-methylbenzyl)ethylenediamine (SL1) and N,N,N',N'-tetra-benzylethylenediamine (SL2), are both the N-bidentate ligands with the bulky substituent groups, and can form the channel between layers with the directional group [CuCl4]2- through the second-sphere coordination. Molecules of cyclopentyl alcohol and ethyl alcohol are accommodated in the channel constructed by SL1 and SL2, respectively, thus forming the inclusion compounds. The analysis results of crystal structure show that such ligands are easy to form bidentate complexes with [CuCl4]2- by NH+⋯Cl- hydrogen bond and construct 1D ribbon and 2D layer structure. In the crystal of SL1, benzyl groups of SL1 between 2D layers stack in parallel motif, leading to 1D hydrophilic channel framework between layers; while in the crystal of SL2, the benzyl groups of SL2 between 2D layers stack in staggered motif, resulting in 1D hydrophobic channel framework between layers. The experimental results show that the size and polarity of channel framework are affected by the molecule length of second ligand, configuration of [CuCl4]2-, and the shape, size of the guest molecules.