Effect of the Presence of Oxysolvents on Compositions and Structures of Silver(I) Complexes with Boron Cluster Anion [B₁₂Cl₁₂]²–

For the first time, a systematic study of the behavior of Ag2[B12Cl12] in oxygen-containing organic solvents of various nature (acetone, N,N-dimethylformamide (DMF), dimethoxyethane (DME), methanol (CH3OH), and tetrahydrofuran (THF)) was conducted. The solvents used were found to compete with the perchlorinated [B12Cl12]2– anion, forming a silver(I) coordination polyhedron. A number of silver(I) coordination compounds of various compositions and structures with solvent molecules acting as ligands were obtained and characterized by physicochemical methods. The structures of polymer complexes {Ag2(solv)x[B12Cl12]}n (x = 4, solv = acetone (1), DMF (2), CH3OH (4), THF (7); x = 2, solv = DME (3)) with the coordinated [B12Cl12]2– anion, as well as coordination compounds [Ag(THF)3]2[B12Cl12] (5) and [Ag(THF)4Ag(THF)2][B12Cl12] (6) with the boron cluster anion as a counterion were determined by single-crystal X-ray diffraction. Furthermore, the complexation of Ag2[B12Cl12] with the organic ligands 18-crown-6 (L1) and 4-methylmorpholine (L2) was investigated. Salts with the complex cations [Ag L1(CH3OH)]+ (8) and [Ag(L2)2]+ (9) were isolated. Based on the results obtained, a plausible pathway for the process of complexation of Ag2[B12Cl12] with organic ligand L in oxygen-containing organic solvents was proposed. The data were confirmed using 109Ag NMR spectroscopy of solutions of Ag2[B12Cl12] salt in individual solvents and their mixtures.