The V-shaped semi-rigid di-4-pyridyl sulfone-N,N′-dioxide ligand and its silver(I), manganese(II) and zinc(II) complexes: Anion tuning and supramolecular assembly

A series of silver(I) complexes bearing the V-shaped di-4-pyridyl sulfone-N,N′-dioxide ligand (abbreviated as L), namely [Ag(L)(NO3)(H2O)]∞ (1), [Ag(L)(CF3SO3)]∞ (2), [Ag(L)(CF3CO2)]∞ (3), [Ag(L)(C2F5CO2)]∞ (4) and {[Ag(L)](ClO4)}∞ (5), and the manganese(II) complex [Mn(L)2(H2O)4](ClO4)2 (6) and the zinc(II) complex [Zn(L)2(H2O)4](ClO4)2 (7) of L have been synthesized and characterized. Under the tuning effect of anions with different coordination capacities and steric bulk, the semi-rigid ligand L exhibits versatile μ2-, μ3- and μ4-bridging modes with the N-oxide and/or sulfonyl O atoms functioning as bonding sites to form a coordination chain structure in complex 1, isostructural nets in 2–4, and a three-dimensional framework in 5. The isostructural mononuclear complexes 6 and 7 exhibit the η1–ON-oxide bonding mode of L. Unusual lone-pair aromatic contacts and anion–π interactions result in supramolecular aggregations of complexes 1–7. The FT-IR spectra and luminescent properties of these complexes have been observed and discussed.

The semi-rigid bi-4-pyridyl sulfone-N,N′-dioxide ligand functions as a flexible linkage in a series of Ag(I), Mn(II) and Zn(II) complexes, which exhibit distinct coordination motifs depending upon the cooperative effect of the metal ion and counter anion present.Figure optionsDownload as PowerPoint slide