Two-dimensional supramolecular networks via C-H···Cl and N-H···Cl interactions utilizing bidentate neutral pyridine amide coordinated Mn^IICl₂ tectons

Abstract

Reaction of N-(phenyl)-2-pyridinecarboxamide (HL¹) and N-(p-tolyl)-2-pyridinecarboxamide (HL²) ligands with MnCl₂·4H₂O affords complexes [(HL¹)2MnCl₂] 1 and [(HL²)2MnCl₂] 2. The structures of 1 and 2 were determined by three-dimensional X-ray crystallography revealing that the Mn^II ions assume distorted octahedral geometry with coordination by two HL¹/HL² ligands providing two pyridine N and two amide O and two chloride ions. Notably, secondary interactions [C-H···Cl (pyridine 3-H hydrogen) and N-H···Cl (amide NH hydrogen)] triggered by Mn^II-coordinated chloride ions acting as hydrogen bonding acceptors generate self-complementary dimeric tectons, which lead to 2D supramolecular architectures.