Investigation of Large Polychloride Anions: [Cl₁₁]⁻, [Cl₁₂]²⁻, and [Cl₁₃]⁻

Abstract

For decades the chemistry of polyhalides was dominated by polyiodides and more recently also by an increasing number of polybromides. However, apart from a few structures containing trichloride anions and a single report on an octachloride dianion, [Cl₈ ]^2- , polychlorine compounds such as polychloride anions are unknown. Herein, we report on the synthesis and investigation of large polychloride monoanions such as [Cl₁₁ ]^- found in [AsPh₄ ][Cl₁₁ ], [PPh₄ ][Cl₁₁ ], and [PNP][Cl₁₁ ]⋅Cl₂ , and [Cl₁₃ ]^- obtained in [PNP][Cl₁₃ ]. The polychloride dianion [Cl₁₂ ]^2- has been obtained in [NMe₃ Ph]₂ [Cl₁₂ ]. The novel compounds have been thoroughly characterized by NMR spectroscopy, single-crystal Raman spectroscopy, and single-crystal X-ray diffraction. The assignment of their spectra is supported by molecular and periodic solid-state quantum-chemical calculations.