Fine-tuning on the structures of 3D CoII/5-methylnicotinate coordination polymers via three different synthetic approaches

Self‐Assembly of Cobalt(II) Coordination Polymers with Differently Halosubstituted Nicotinate Ligands and 4,4’‐Bipyridine – The Effect of the Halosubstituent Positions on Polymer Types

“…The octahedral coordination environments around the cobalt(II) ions in 1 and 2 are only slightly distorted, as is evident from the angles for the cis pairs of the ligating atoms (Table S1 in the supporting information). The CoÀ O (carboxylate O atom) bond lengths in 1 are comparable to those seen in the related cobalt(II) complexes with nicotinate ligands, [18,23,[27][28][29][30] while the CoÀ N bond lengths could be compared to those reported for cobalt(II) complexes containing bridging 4,4'-bipyridine ligands. [13] The CoÀ O and CoÀ N bond lengths in the {[Co(4,4'bpy)(H 2 O) 4 ] 2 + } n cation of 2 are identical as in the other structures containing this cation, [13] while the CoÀ O and CoÀ N bond lengths in the [Co(5-Br-nic) 4 (H 2 O) 2 ] 2À anion of 2 are comparable to those seen in the related cobalt(II) complexes with nicotinate ligands.…”

“…[13] The CoÀ O and CoÀ N bond lengths in the {[Co(4,4'bpy)(H 2 O) 4 ] 2 + } n cation of 2 are identical as in the other structures containing this cation, [13] while the CoÀ O and CoÀ N bond lengths in the [Co(5-Br-nic) 4 (H 2 O) 2 ] 2À anion of 2 are comparable to those seen in the related cobalt(II) complexes with nicotinate ligands. [13,18,23,[27][28][29][30] The extended structures of 1 and 2 mainly feature strong OÀ H•••O and OÀ H•••N hydrogen bonds, weak CÀ H•••O hydrogen bonds (Table S2 in the supporting information) and π-π interactions. The strong hydrogen bonds link the polymeric chains of 1 and the lattice water molecules into an infinite three-dimensional network.…”