title: Polymorphism in ammonium 2,4,6-trimethylbenzenesulfonate.
abstract: During investigations into sulfide- and selenide-amination reactions using the aminating agent o-mesitylsulfonylhydroxylamine, the monoclinic, (I), and orthorhombic, (II), polymorphs of ammonium 2,4,6-trimethylbenzenesulfonate, NH4+.C9H11O3S-, have been crystallized. Investigation of the hydrogen-bonding motifs within the two polymorphs shows that both contain N+-H...O- hydrogen bonds between the ammonium cations and the 2,4,6-trimethylbenzenesulfonate anions. Polymorph (I) contains R(4)(4)(12) and R(4)(2)(8) graph-set ring motifs, while polymorph (II) contains the same R(4)(4)(12) ring motif in combination with an R(4)(3)(10) motif. The two hydrogen-bonding patterns result in slightly different packing structures for the two polymorphs, but both are based on a thick-sheet arrangement, in which the NH4+ cations are enveloped between two layers of 2,4,6-trimethylbenzenesulfonate anions. In (I), the aromatic rings of the anions are approximately coplanar, giving parallel sheets, whereas in (II) the sheets are antiparallel and the anions pack in a herring-bone manner within the sheets, with angles of 78.76 (8) degrees between the planes of the aromatic rings.
authors.affiliation: Chemistry Department, Loughborough University, Loughborough, Leicestershire LE11 3TU, England.
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Aucott
authors.forename: Sophie H
authors.initials: SH
authors.lastname: Dale
authors.forename: Mark R J
authors.initials: MR
authors.lastname: Elsegood
authors.forename: Kathryn E
authors.initials: KE
authors.lastname: Holmes
authors.forename: Liam M
authors.initials: LM
authors.lastname: Gilby
authors.forename: Paul F
authors.initials: PF
authors.lastname: Kelly