trans-Dichlorido-tetra-kis-[(di-methyl-phosphor-yl)methanaminium-κO]cobalt(II) tetra-chloridocobaltate(II)

A third polymorph of the zwitterionic complex trichlorido-((dimethylphosphoryl)methanaminium-κO)zinc(II)

By the reaction of (dimethylphosphoryl)methanamine (dpma) with one equivalent of zinc(II) chloride in a concentrated hydrochloric acid solution and subsequent slow evaporation of the solvent, the title compound (dpmaH)ZnCl3 was obtained in quantitative yield. The primary reaction product mainly consists of larger brick-shaped colorless and smaller cuboide colorless crystals. Long-time storage over several months of these crystals in the mother liquor yielded a third polymorph (P21/n; a = 9.6639(1); b = 10.0271(1); c = 11.2446(1) Å; β = 98.964(1)°) of this compound. Similar to the two other modifications, its crystal structure consists of a zwitterionic dpmaHZnCl3 complex containing the cationic dpmaH+ ligand, which coordinates the zinc atom through its oxygen atom. Hydrogen bonds connect neighboring zwitterionic complexes to a layered structure. The motif of a hydrogen bonded dimer, similar to that found in the chain structure of polymorph I, is also present, but in the title structure these dimers form hydrogen bonds in two dimensions.

(Di-methyl-phosphor-yl)methanaminium hydrogen oxalate-oxalic acid (2/1)

The reaction of (di­methyl­phosphor­yl)methanamine (dpma) with oxalic acid in ethanol yielded the title solvated salt, C₃H₁₁NOP⁺·C₂HO₄⁻·0.5C₂H₂O₄. Its asymmetric unit consists of one dpmaH⁺ cation, one hydrogen oxalate anion and a half-mol­ecule of oxalic acid located around a twofold rotation axis. The H atom of the hydrogen oxalate anion is statistically disordered over two positions that are trans to each other. The hydrogen oxalate monoanion is not planar (bend angle ∼16°) whereas the oxalic acid molecule shows a significantly smaller bend angle (∼7°). In the crystal, the components are connected by strong O—H⋯O and much weaker N—H⋯O hydrogen bonds, leading to the formation of layers extending parallel to (001). The structure was refined from a racemically twinned crystal with twin components in an approximate 1:1 ratio.

1-(4-Hy-droxy-phen-yl)piperazine-1,4-diium tetra-chlorido-cobalt(II) monohydrate

The asymmetric unit of the title inorganic-organic hybrid compound, (C10H16N2O)[CoCl4]·H2O, consists of a tetrahedral [CoCl4](2-) anion, together with a [C10H18N2O](2+) cation and a water mol-ecule. Crystal cohesion is achieved through N-H⋯Cl, O-H⋯Cl and N-H⋯O hydrogen bonds between organic cations, inorganic anions and the water mol-ecules, building up a three-dimensional network.

Bis[(di-methyl-phosphor-yl)methan-amin-ium] tetra-chlorido-palladate(II)

In the crystal structure of the title compound, (C₃H₁₁NOP)₂[PdCl₄], (di­methyl­phosphor­yl)methanaminium (dpmaH⁺) cations are connected head-to-tail by strong N—H⋯O hydrogen bonds, forming inversion-related cyclic dimers. The square-planar [PdCl₄]²⁻ counter-dianion is located about a center of inversion. The dications and the [PdCl₄]²⁻ dianions are connected by medium–strong N—H⋯Cl hydrogen bonds, forming zigzag chains parallel to [001]. Somewhat weaker N—H⋯Cl hydrogen bonds connect the chains into a three-dimensional network.

(Di-methyl-phosphor-yl)methanaminium nitrate

In the crystal of the title salt, C3H11NOP(+)·NO3 (-), dicationic inversion dimers are head-to-tail connected by a pair of strong N-H⋯O hydrogen bonds. The resulting graph-set descriptor of this ring system is R 2 (2)(10). The nitrate counter-anions connect the dicationic dimers via N-H⋯O hydrogen bonds, forming two-dimensional networks in the bc plane.

(Di-methyl-phosphor-yl)methanaminium iodide-(di-methyl-phosphor-yl)methan-amine (1/1)

The asymmetric unit of the title structure, C3H11NOP(+)·I(-)·C3H10NOP, consists of one (di-methyl-phosphor-yl)methanamine (dpma) mol-ecule, one (di-methyl-phosphor-yl)methanaminium (dpmaH) ion and one iodide counter-anion. In the crystal, medium-strong to weak N-H⋯O and N-H⋯N hydrogen bonds connect dpmaH cations and dpma mol-ecules into strands along [001]. The iodide counter-anions form only very weak hydrogen bonds. The crystal used for the diffraction study was found to be an inversion twin with a ratio of 0.83 (2):0.17 (2). The title structure is isotypic to that of dpmaH[ClO4]·dpma [Buhl et al. (2013 ▶). Crystals 3, 350-362].