title: The crystal structures of three clozapinium salts: different mol-ecular configurations, and supra-molecular assembly in one, two and three dimensions.
abstract: The structures of three salts derived from clozapine, 8-chloro-11-(4-methyl-piperazin-1-yl)-5H-dibenzo[b,e][1,4]diazepine, are reported, namely, clo-za-pin-ium 3,5-di-nitro-benzoate dimethyl sulfoxide monosolvate, C18H20ClN4 (+)·C7H3N2O6 (-)·C2H6OS, (I), where the dimethyl sulfoxide component is disordered over two sets of atomic sites having occupancies 0.627 (2) and 0.373 (2); clo-za-pin-ium hydrogen maleate 0.21-hydrate, C18H20ClN4 (+)·C4H3O4 (-)·0.21H2O, (II), and clozapinium 2-hy-droxy-benzoate, C18H20ClN4 (+)·C7H5O3 (-), (III). In all three salts, the protonation site is the methyl-ated N atom of the piperazine ring, and the dimensions and conformations of the fused tricyclic system are very similar. However, differences are apparent in the piperazine component: in both compounds (II) and (III), the unprotonated N atom of this ring has a pyramidal geometry, but in compound (I) this atom has a planar geometry. In compound (III), both N-substituents in this ring occupy equatorial sites, but in compound (II) the fused tricyclic system occupies an axial site of the piperazine ring. The independent components of compound (I) are linked within the selected asymmetric unit by a combination of N-H⋯O and C-H⋯O hydrogen bonds, and these hydrogen-bonded aggregates are linked into chains by an aromatic π-π stacking inter-action. In compound (II), the components are linked into sheets by a combination of O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds, and in compound (III), a combination of N-H⋯O, C-H⋯O and C-H⋯N hydrogen bonds links the components into a three-dimensional framework structure. Comparisons are made with some similar compounds.
authors.affiliation: Department of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570 006, India.
authors.forename: Manpreet
authors.initials: M
authors.lastname: Kaur
authors.affiliation: Department of Chemistry, Keene State College, 229 Main Street, Keene, NH 03435-2001, USA.
authors.forename: Jerry P
authors.initials: JP
authors.lastname: Jasinski
authors.affiliation: Department of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570 006, India.
authors.forename: Hemmige S
authors.initials: HS
authors.lastname: Yathirajan
authors.affiliation: Department of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570 006, India.
authors.forename: Channappa N
authors.initials: CN
authors.lastname: Kavitha
authors.affiliation: School of Chemistry, University of St Andrews, St Andrews, Fife KY16 9ST, Scotland.
authors.forename: Christopher
authors.initials: C
authors.lastname: Glidewell
keywords: clozapinium; crystal structure; hydrogen bonding; mol­ecular configuration; supra­molecular assembly