Self-assembly of silver(I) polymers with single strand double-helical structures containing the ligandO,O′-bis(8-quinolyl)-1,8-dioxaoctane

Abstract

The flexible multidentate ligand O,O′-bis(8-quinolyl)-1,8-dioxaoctane (ODOQ) reacted with AgX (X = ClO₄⁻, BF₄⁻, CF₃SO₃⁻, or CF₃CO₂⁻) to give four new complexes [Ag(ODOQ)]_nX_n: X = ClO₄⁻1; X = BF₄⁻2; X = CF₃SO₃⁻3, and [Ag(ODOQ)(CF₃CO₂)]_n4. All four complexes have been characterized by elemental analyses, IR and ¹H NMR spectroscopy. Single crystal X-ray analyses showed that they have similar 1-D extended architectures with each ligand in “∼” shape, while the chains are alternately and parallelly arranged with the silver(I) atoms as the backbone to form double helical mesomeric strands. The structures are controlled more by the spacer (CH₂)₆ than by the anions: the versatile coordination geometry of the silver(I) atom is trigonally bonded but changes to distorted tetrahedral or trigonal bipyrimidal via weak Ag⋯O interactions. In addition, face-to-face π⋯π (in 1–4) and edge-to-face C–H⋯π (in 3) interactions as well as hydrogen bonds C–H⋯O and C–H⋯F between adjacent strands assemble the cations in 1–3 or neutral molecules in 4 into an extended network.