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

Abstract

For the first time, a systematic study of the behavior of Ag 2 [B 12 Cl 12 ] in oxygencontaining organic solvents of various nature (acetone, N,N-dimethylformamide (DMF), dimethoxyethane (DME), methanol (CH 3 OH), and tetrahydrofuran (THF)) was conducted. The solvents used were found to compete with the perchlorinated [B 12 Cl 12 ] 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 {Ag 2 (solv) x [B 12 Cl 12 ]} n (x = 4, solv = acetone (1), DMF (2), CH 3 OH (4), THF (7); x = 2, solv = DME (3)) with the coordinated [B 12 Cl 12 ] 2− anion, as well as coordination compounds [Ag(THF) 3 ] 2 [B 12 Cl 12 ] (5) and [Ag(THF) 4 Ag(THF) 2 ][B 12 Cl 12 ] (6) with the boron cluster anion as a counterion were determined by single-crystal X-ray diffraction. Furthermore, the complexation of Ag 2 [B 12 Cl 12 ] with the organic ligands 18-crown-6 (L 1 ) and 4-methylmorpholine (L 2 ) was investigated. Salts with the complex cations [Ag L 1 (CH 3 OH)] + (8) and [Ag(L 2 ) 2 ] + (9) were isolated. Based on the results obtained, a plausible pathway for the process of complexation of Ag 2 [B 12 Cl 12 ] with organic ligand L in oxygen-containing organic solvents was proposed. The data were confirmed using 109 Ag NMR spectroscopy of solutions of Ag 2 [B 12 Cl 12 ] salt in individual solvents and their mixtures.