Sulfur-Containing Mixed-Donor Tribenzo-Macrocycles and Their Endo- and Exocyclic Supramolecular Silver(I) and Copper(I) Complexes

New sulfur-containing mixed-donor macrocycles L1−L4 with different donor sets and/or ring sizes (L1, 20-membered O3S2; L2, 20-membered NO2S2; L3, 20-membered O2S3; and L4, 23-membered O4S2) were synthesized and structurally characterized by X-ray analysis. A comparative investigation of the coordination behavior of these macrocyclic ligands with silver(I) salts and copper(I) iodide is reported. The X-ray structures of seven complexes (1−7) have been determined, and a range of structural types and coordination modes, including mono- to multinuclear and endo- to exocyclic ones via M−S bonds, is shown to occur. In all seven complexes, the ether oxygens of each ring are unbound. Reactions of L1−L4 with the silver(I) salts (ClO4−, BF4−, and NO3−) afforded four complexes with different topologies: the exocyclic 1-D coordination polymer [Ag(L1)(ClO4)]n (1), the endocyclic 1:1 monomer complex [Ag(L2)]ClO4·CH3OH (2), the endo-/exocyclic 1-D coordination polymer {[Ag2(L2)(CH3OH)](BF4)2}n (3), and the cyclic dimer complex [Ag2(L3)2(NO3)2]·2CH3CN (4). NMR titrations of L1 and L2 with silver(I) perchlorate were carried out to explore their complexation behavior in solution and also for comparison with the solid state structures. As well, reaction of the above ligands with copper(I) iodide afforded the exocyclic dimer, [Cu2I2(L1)2]·CH2Cl2 (5), linked with diamond-type Cu−I2−Cu unit, the exocyclic monomer complex [CuI(L3)]·CH2Cl2 (6), and the emissive 1-D poly(cyclic dimer) complex {[Cu4I4(L4)2]·CH2Cl2}n (7) linked by a cubane-type Cu4I4 unit. The formation of both the discrete and continuous supramolecular complexes with copper(I) iodide is discussed in terms of a ligand-directed “sulfur-to-sulfur” distance effect.