Exploring the Role of Strong Intramolecular Coordination of the 2‐(2'‐pyridyl)phenyl Group in Heavy Main Group Halides: Insights from Synthesis, Structural, and Bonding Analyses

Abstract

By the transmetallation of ppyHgCl [ppy = 2‐(2'‐pyridyl)phenyl] (1) with SnCl4 and SbCl3, the synthesis of the monoorgano main group halides, [ppySnCl3(H2O)]·2(0.5diox) (diox = 1,4‐dioxane) [2(H2O)]·2(0.5diox) and [ppySbCl2] (3) was achieved. The reaction of 1 with BiCl3 does not give the analogous monoorganobismuth dichloride. Instead, it results in the formation of [(ppy)2Bi]+·[ppyBiCl3]– (4). Reactions of (ppy)2Te and (ppyTe)2 with SO2Cl2 and Br2 result in the formation of ppyTeCl (5) and ppyTeBr (6) respectively. All the synthesized compounds were characterized by multi‐nuclear NMR spectroscopy (1H, 13C, 119Sn, and 125Te), FT‐IR spectroscopy, ESI‐MS, CHN analysis, and single‐crystal X‐ray diffraction studies. The molecular structures of 2–6 reveal strong intramolecular coordination of the N‐atoms of the pendant arms with the main group element centers. DFT calculations; including Natural Bond Order (NBO), Electron Localization Function (ELF), Electrostatic Surface Potential (ESP) and Atoms in Molecules (AIM) infer that the stability of 2–6 relies on the σ‐hole participation of the element center with the N‐lone pair of the pyridyl arm.