Polysulfonylamine, CLXXXVI [1]. Strukturvielfalt in sechs Cokristallen von Tetramethylharnstoff mit Di(4-X-benzolsulfonyl)aminen (X = F, Cl, Br, I, CH3, NO2) / Polysulfonylamines, CLXXXVI [1]. Structural Diversity in Six Tetramethylurea Di(4-X-benzenesulfonyl) amine Cocrystals (X = F, Cl, Br, I, CH3, NO2)

• Published in: Zeitschrift für Naturforschung. B, A journal of chemical sciences Vol. 63; no. 11; pp. 1276 - 1290
• Main Authors: Zerbe, Eva-Maria, Piñol, Silvia Roca, Hamann, Thomas, Freytag, Matthias, Jones, Peter G., Blaschette, Armand
• Format: Journal Article
• Language: English
• Published: Verlag der Zeitschrift für Naturforschung 01-11-2008
• Subjects: Cocrystals; Dipolar Nitro-Nitro Interactions; Halogen Bonding; Hydrogen Bonding; Sulfonamides; Tetramethyluronium Ion
• ISSN: 0932-0776; 1865-7117
• DOI: 10.1515/znb-2008-1106

Cocrystallization of tetramethylurea (TMU) with one equivalent of either di(4-fluorobenzenesulfo- nyl)amine (FAH), di(4-chlorobenzenesulfonyl)amine (CAH), di(4-bromobenzenesulfonyl)amine (BAH). di(4-iodobenzenesulfonyl)amine (IAH), di(4-methylbenzenesulfonyl)aniine (MAH>, ordi(4- nitrobenzenesulfonyDamine (NAH), using dichloromethane/petroleum ether as the solvent, afforded the molecular complexes (FAH)
· TMU (1. monoclinic. P2
/c,Z' = 1. structure previously reported), CAHTMU, BAH-TMU and IAH-TMU (2-4, isomorphic series, triclinic, P1̅,Z' = 1), MAH · TMU (5, monoclinic. P2
, Z' = 1). and the uranium salt TMUH
NA
(6, monoclinic. P2
/c,Z' = 2). The structural results obtained by X-ray crystallography at low temperatures indicate that the varying p- substituents of the di(arenesulfonyl)amines exert a decisive influence on (i) the stoichiometry of the cocrystallization reaction (2:1 for 1 vs. 1:1 for 2-6), (ii) the degree of proton transfer between the strongly acidic (SO
NH moieties and the basic carbonyl function of TMU (molecular complexes assembled via N-H···O=C hydrogen bonds in 1 -5 vs. two independent ion pairs based upon charge- assisted C-O-H
···N
interactions in 6). and (Hi) the conformation of the disulfonylamineZ-amide units as defined by rotations about the S-N bonds (extended forms displaying anticlinal C-S ··· S'- C' torsions for the two molecules in 1 and the two anions in 6 vs. folded forms featuring synperi- planar C-S ···S'-C torsions for the molecules in 2-5). The packing modes of 1-4 underline the well-known correlation between the atomic number of halogen atoms and their propensity to form halogen bonds. Thus, the structure of 1 is devoid of short F···O contacts, whereas the isomorphic co- crystals 2-4 consist of lamellar layers in which the inner lamellae include the TMU molecules and the peripheral regions are built up from CAH, BAH or IAH molecules associated into catemers via C-Hal ··· O=S bonds. The lamellar layers of the non-isomorphic methyl congener 5. although topological^' similar to those of 2-4, are stacked according to a herringbone pattern that does not arise in the structures of 2-4. The most prominent packing feature of the uranium salt 6 are intimate dimers of two independent NA
ions, stabilized by dipolar nitro-nitro interactions and C-H ··· O=S contacts and further connected into monolayers through C-H ··· O
contacts. The uranium ions are inserted between these layers and bonded to the anion dimers by the strong hydrogen bonds mentioned above and numerous C-H ··· O
contacts. The presence of two independent formula units appears to arise from frustration between several competing interactions, e. g. dipolar nitro attractions, weak hydrogen bonding to sulfonyl and nitro acceptors and π/π stacking of aromatic rings.