Mono- and dinuclear silver(I) complexes of benzene- and pyridine-bearing 20-membered thiaoxaaza macrocycles

Two 20-membered penta- and hexadentate macrocycles containing one or two pyridine subunits, namely [20]aneNO2S2 (L1) and [20]aneN2O2S2 (L2), have been synthesized. Reaction of L1 with silver(I) nitrate afforded a unique 2:2 (M:L) disilver(I) complex [μ2-Ag2(L1)2](NO3)2 (1) in which two four-coordinate Ag atoms bridge two ligands to form a cyclic dimer. In contrast, an endo-dentate 1:1 monosilver(I) complexes [AgL2]X; [X = ClO4 (2) or PF6 (3)] which show isomorphous structures were obtained from the reactions of L2 with silver(I) salts.