Conformation Restriction of Nonplanar Di-2-pyrimidyl Sulfide with Intramolecular N···C Interaction and Its Supramolecular Silver(I) Complexes

A series of silver­(I) complexes with semirigid di-2-pyrimidyl sulfide (DprS), namely, {[Ag₂(DprS)₂(CF₃CO₂)]­(CF₃CO₂)·2H₂O}_∞ (1), {[Ag₆(DprS)₆(CF₃SO₃)₅]­(CF₃SO₃)·3.5H₂O}_∞ (2), {[Ag₂(DprS)­(C₂F₅CO₂)₂]}_∞ (3), [Ag­(DprS)­(NO₃)_∞ (4), and {[Ag₃(DprS)₃]­(ClO₄)₃}_∞ (5), have been synthesized and characterized by single-crystal X-ray analysis. The silver­(I) complexes 1–2 and 4–5 exhibit one-dimensional tape-like coordination polymers with different topological structures, while complex 3 has a two-dimensional coordination network. In these complexes, the two pyrimidyl rings of each DprS are almost in an orthogonal orientation, a rigid nonplanar conformation, and the multidentate ligand adopts an unvaried N,N′,N″-μ₃ ligation mode despite the different anions (CH₃COO^– in 1, CF₃SO₃^– in 2, C₂F₅COO^– in 3, NO₃^– in 4, and ClO₄^– in 5). Attractive intramolecular N_pyrimidyl···C_pyrimidyl interaction between a 1-positional N atom of one pyrimidyl ring and an electrophilic 2-positional C atom of the other ring of DprS is a common dominant interaction, which drives and stabilizes the nonplanar ligand conformation in these crystalline structures. Calculation through the self-consistent field crystal orbital method based on density functional theory indicates the presence of the N···C contact, a nucleophile–electrophile affinity. Unconventional anion−π_pyrimidyl interactions engaged in the construction of the supramolecular architectures of 1–5 also are presented and discussed.