The crystal structures of three clozapinium salts: different mol-ecular configurations, and supra-molecular assembly in one, two and three dimensions

A very short O-H⋯O hydrogen bond in the structure of clozapinium hydrogen bis-(3,5-di-nitro-benzoate)

In the title salt {systematic name: 4-[6-chloro-2,9-di-aza-tri-cyclo-[9.4.0.03,8]penta-deca-1(15),3(8),4,6,9,11,13-heptaen-10-yl]-1-methyl-piperazin-1-ium 3,5-di-nitro-benzoate-3,5-di-nitro-benzic acid (1/1)}, C18H20ClN4 +·C7H3N2O6 -·C7H4N2O6, there is a very short, asymmetric, O-H⋯O hydrogen bond [O⋯O = 2.453 (3) Å] within the anion. The oxygen atoms of one of the nitro groups of the anion are disordered over two sets of sites having occupancies of 0.56 (3) and 0.44 (3). The fused tricyclic portion of the cation adopts a butterfly conformation, with a dihedral angle of 45.59 (6)° between the planes of the two aryl rings. In the crystal, a combination of O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds links the component species into a three-dimensional framework. Comparisons are made with the structures of some related compounds.

Twelve 4-(4-meth-oxy-phen-yl)piperazin-1-ium salts containing organic anions: supra-molecular assembly in one, two and three dimensions

Twelve 4-(4-meth-oxy-phen-yl)piperazin-1-ium salts containing organic anions have been prepared and structurally characterized. The monohydrated benzoate, 4-fluoro-benzoate, 4-chloro-benzoate and 4-bromo-benzoate salts, C11H17N2O+·C7H5O2 -·H2O (I), C11H17N2O+·C7H4FO2 -·H2O (II), C11H17N2O+·C7H4ClO2 -·H2O (III), and C11H17N2O+·C7H4BrO2 -·H2O (IV), respectively, are isomorphous and all exhibit disorder in the 4-meth-oxy-phenyl unit: the components are linked by N-H⋯O and O-H⋯O hydrogen bond to form chains of rings. The unsolvated 2-hy-droxy-benzoate, pyridine-3-carboxyl-ate and 2-hy-droxy-3,5-di-nitro-benzoate salts, C11H17N2O+·C7H5O3 - (V), C11H17N2O+·C6H4NO2 - (VI) and C11H17N2O+·C7H3N2O7 - (VII), respectively, are all fully ordered: the components of (V) are linked by multiple N-H⋯O hydrogen bonds to form a chain of rings; those of (VI) are linked into a three-dimensional framework by a combination of N-H⋯O, C-H⋯O and C-H⋯N hydrogen bonds and those of (VII), where the anion has a structure reminiscent of the picrate anion, are linked into a three-dimensional array by N-H⋯O and C-H⋯O hydrogen bonds. The hydrogensuccinate and hydrogenfumarate salts, C11H17N2O+·C4H5O4 - (VIII) and C11H17N2O+·C4H3O3 - (IX), respectively, are isomorphous, and both exhibit disorder in the anionic component: N-H⋯O and O-H⋯O hydrogen bonds link the ions into sheets, which are further linked by C-H⋯π(arene) inter-actions. The anion of the hydrogenmaleate salt, C11H17N2O+·C4H3O3 - (X), contains a very short and nearly symmetrical O⋯H⋯O hydrogen bond, and N-H⋯O hydrogen bonds link the anions into chains of rings. The ions in the tri-chloro-acetate salt, C11H17N2O+·C2Cl3O2 - (XI), are linked into simple chains by N-H⋯O hydrogen bonds. In the hydrated chloranilate salt, 2C11H17N2O+·C6Cl2O4 2-·2H2O (XII), which crystallizes as a non-merohedral twin, the anion lies across a centre of inversion in space group P21/n, and a combination of N-H⋯O and O-H⋯O hydrogen bonds generates complex sheets. Comparisons are made with the structures of some related compounds.

The heterogeneous crystallization of a novel solvate of clozapine base in the presence of excipients

This paper reports the heterogeneous crystallization of a novel solvate of clozapine base in the presence of excipients.