Room-Temperature Synthesis of [BMIm][Sn5O2Cl7] with ∞1(Sn2OCl2) Strands in a Saline [BMIm][SnCl3] Matrix

Silke Wolf; Stefan Seidel; Jens Treptow; Ralf Köppe; Peter W Roesky; Claus Feldmann

doi:10.1021/acs.inorgchem.1c03763

Room-Temperature Synthesis of [BMIm][Sn₅O₂Cl₇] with _∞¹(Sn₂OCl₂) Strands in a Saline [BMIm][SnCl₃] Matrix

Inorg Chem. 2022 Mar 7;61(9):4018-4023. doi: 10.1021/acs.inorgchem.1c03763. Epub 2022 Feb 24.

Authors

Silke Wolf¹, Stefan Seidel², Jens Treptow¹, Ralf Köppe¹, Peter W Roesky¹, Claus Feldmann¹

Affiliations

¹ Institute for Inorganic Chemistry, Karlsruhe Institute of Technology, Engesserstraße 15, D-76131 Karlsruhe, Germany.
² Institute for Inorganic and Analytical Chemistry, University of Münster, Corrensstraße 28/30, D-48149 Münster, Germany.

Abstract

The novel tin(II) oxychloride [BMIm][Sn₅O₂Cl₇] (BMIm = 1-butyl-3-methylimidazolium) is obtained by the room-temperature reaction (25 °C) of black SnO and SnCl₂ in [BMIm]Cl/SnCl₂ as an ionic liquid. The title compound can be described as composed of noncharged, infinite _∞¹(Sn₂OCl₂) strands that are embedded in a saline matrix of [BMIm]⁺ and [SnCl₃]^-. The _∞¹(Sn₂OCl₂) strands consist of a backbone of edge-sharing OSn_4/2 tetrahedra, which represent one-dimensional (1D) strands cut out of the layer-type structure of SnO. In [BMIm][Sn₅O₂Cl₇], the _∞¹(Sn₂OCl₂) strands, which mimic a 1D semiconductor, are terminated by chlorine atoms, whereas they are interconnected by oxygen atoms in the 2D semiconductor SnO. The view of the noncharged _∞¹(Sn₂OCl₂) strands in a saline [BMIm][SnCl₃] matrix is validated by dissolution experiments. Thus, electron microscopy and Raman spectroscopy show a deconstruction of [BMIm][Sn₅O₂Cl₇] single crystals after treatment with chloroform with a dissolution of [BMIm][SnCl₃], the formation of SnCl₂ needles, and tin oxide as a solid remain.