Linear bis‐Coordinate Silver(I) and Iodine(I) Complexes with R3R2R1N Tertiary Amines

Abstract

Homoleptic [L–I–L]⁺ iodine(I) complexes (where L is a R3R2R1N tertiary amine) were synthesized via the [L–Ag–L]⁺ → [L–I–L]⁺ cation exchange reaction. In solution, the amines form [R3R2R1N-Ag-NR1R2R3]⁺ silver(I) complexes, which crystallize out from solution as the meso-[L–Ag–L]+complexes, as characterized by X-ray crystallography. The subsequent [L–I–L]⁺ iodine(I) analogues were extremely reactive and could not be isolated in the solid state. Density Functional Theory (DFT) calculations were performed to study the Ag⁺–N and I⁺–N interaction energies in silver(I) and iodine(I) complexes, with the former ranging from -80 to -100 kJmol-1 and latter from -260 to -279 kJmol-1. The X-ray crystal structures revealed Ag+···Cπ and Ag+···H–C short contacts between the silver(I) cation and flexible N-alkyl/N-aryl groups, which are the first of their kind in such precursor complexes.