A series of silver(I) coordination polymers with saccarinate and flexible aliphatic diamines

Abstract

A series of Ag(I) complexes with aliphatic diamines having a different chain length (NH2-(CH2)n-NH2, n=4–9), with the formulas, [Ag(μ-sac)(μ-db)0.5]n (1), {[Ag4(sac)4(μ-dp)2]·4H2O}n (2), {[Ag2(sac)2(μ-dz)]·2H2O}n (3), {[Ag2(sac)2(μ-dh)]·H2O}n (4), {[Ag2(sac)2(μ-do)]·H2O}n (5a), [Ag2(sac)2(μ-do)2] (5b) and [Ag4(sac)4(μ-dn)2]·2H2O (6), where sac=saccharinate, db=1,4-diaminobutane, dp=1,5-diaminopentane, dz=1,6-diaminohexane, dh=1,7-diaminoheptane, do=1,8-diaminooctane and dn=1,9-diaminononane, were synthesized and characterized by elemental analysis, infrared spectra and single-crystal X-ray diffraction analysis. In 1, the sac ligand bridges adjacent Ag(I) ions through the nitrogen and carbonyl oxygen atoms to form eight-membered bimetallic rings with the Ag···Ag distance being 3.897Å, which are linked by db ligands to give a 1D zigzag chain. The complexes 2–5a consist of a one-dimensional (1D) linear cationic chains and discrete mononuclear anions. The discreet complex units are further connected by ligand unsupported argentophilic interactions. In 6, the dn ligands bridge adjacent silver centers to form 24-membered macrometallacyclic rings, which are further connected to the anionic [Ag(sac)2]- units by argentophilic Ag1···Ag2 interactions to form a tetranuclear structure. The adjacent dinuclear units are further linked together through ligand-unsupported argentophilic Ag···Ag (3.207(1)Å) interactions, generating a one-dimensional linear chain. The most striking feature of complexes is the presence of the rare intermolecular C-H···Ag interactions. In 5b, the do ligand bridges two Ag(I) ions to form a dinuclear with a 22-membered macrometallacyclic ring. Furthermore, biological activities, luminescence properties and thermal analysis (TG/DTA) of the complexes were investigated.