Polysulfonylamine, LXXVI [1] Zwei supramolekulare Isomere im gleichen Kristall: Darstellung und Struktur des monomeren 18-Krone-6-Komplexes (CH2CH2O)6·2 MeN(SO2Me)(SO2Ph) / Polysulfonylamines, LXXVI [1] Occurrence of Two Supramolecular Isomers in One Crystal: Synthesis and Structure of the Monomeric 18-Crown-6 Complex (CH2CH2O)6 • 2 MeN(SO2Me) (SO2Ph)

Abstract

The title complex, obtained by co-crystallization of its molecular components from methanol, was characterized by low-temperature X-ray diffraction. The crystal structure (triclinic, space group P1̄, Z = 2) consists of two monomeric and crystallographically centrosymmetric formula units A and B which may be classified as supramolecular stereo- and/or linkage isomers. In both units, the receptor rings adopt the frequently observed D3d pseudosymmetry, and the symmetry-related substrate molecules are situated above and below the polyether rings. The isomerism of the supermolecules arises from markedly different confomations of their substrate components. In B, the methyl groups display a transoid orientation (torsional angle for C - N - S - C : 135.5°) and the N-methyldisulfonylamine is solely attached by three S - C - H ··· O interactions to a set of three alternating crown oxygen atoms. In isomer A, the C -N - S - Cmethyl sequence is cisoid (torsional angle: 83.1°) and the substrate is connected to the crown ether by three S - C - H ··· O bonds and an additional N - C - H ··· O interaction. The H ··· O distances and C -H ··· O angles of the seven independent hydrogen bonds lie within the intervals 230-260 pm and 140-180°, respectively. A supermolecule involving MeN (SO2Ph)2 and 18-crown-6 could not be isolated, whereas the binary complex (CH2CH2O)6•2 MeN(SO2F)2 is readily obtained by co-crystallization of the components. The latter complex showed severe disorder of the N(SO2F)2 moieties and its structure could not be refined satisfactorily.