2-Amino­pyridinium diphenyl­phosphinate monohydrate

Mohammad Nazari; Alireza Abbasi; Ali Nemati Kharat; Mohammad Reza Hantehzadeh

doi:10.1107/S1600536809033856

. 2009 Aug 29;65(Pt 9):o2300. doi: 10.1107/S1600536809033856

2-Aminopyridinium diphenylphosphinate monohydrate

Mohammad Nazari ^a, Alireza Abbasi ^a,^*, Ali Nemati Kharat ^a, Mohammad Reza Hantehzadeh ^b

PMCID: PMC2969954 PMID: 21577689

Abstract

In the crystal of the title hydrated salt, C₅H₇N₂ ⁺·C₁₂H₁₀O₂P⁻·H₂O, the cations, anions and water molecules connected by N—H⋯O and O—H⋯O hydrogen bonds into a layer along the bc plane; the phenyl rings protrude into the space between the layers. The dihedral angle between rings of anion is 86.1 (1)°.

Related literature

For bidentate ligands with both hard (nitrogen) and soft (phosphorous) donors, see: Espinet & Soulantica (1999 ▶); Jeffrey & Rauchfuss (1979 ▶). For the use of diphenylphosphinic acid in the extraction of trivalent lanthanide cations and as a flame retardant in the epoxy resins used in printed circuit boards, see: Almeida (1974 ▶); von Gentzkow et al. (1996 ▶); Huber et al. (1998 ▶).

Experimental

Crystal data

C₅H₇N₂ ⁺·C₁₂H₁₀O₂P⁻·H₂O
M _r = 330.31
Monoclinic,
a = 15.2716 (19) Å
b = 9.979 (2) Å
c = 11.7671 (15) Å
β = 103.073 (10)°
V = 1746.8 (5) Å³
Z = 4
Mo Kα radiation
μ = 0.17 mm⁻¹
T = 295 K
0.60 × 0.35 × 0.21 mm

Data collection

Stoe IPDS-II diffractometer
Absorption correction: analytical (X-SHAPE; Stoe & Cie, 2007 ▶) T _min = 0.813, T _max = 0.965
8165 measured reflections
2972 independent reflections
1660 reflections with I > 2σ(I)
R _int = 0.097

Refinement

R[F ² > 2σ(F ²)] = 0.054
wR(F ²) = 0.130
S = 1.02
2972 reflections
214 parameters
3 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.21 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Data collection: X-RED (Stoe & Cie, 2007 ▶); cell refinement: X-AREA (Stoe & Cie, 2007 ▶); data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: DIAMOND (Brandenburg, 2001 ▶); software used to prepare material for publication: PLATON (Spek, 2009 ▶).

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809033856/ng2622sup1.cif

e-65-o2300-sup1.cif^{(17.2KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809033856/ng2622Isup2.hkl

e-65-o2300-Isup2.hkl^{(145.9KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯O1	0.86	1.80	2.655 (4)	175
N2—H13⋯O2	0.86	2.02	2.881 (4)	176
N2—H14⋯O3ⁱ	0.86	2.04	2.853 (4)	157
O3—H3A⋯O2ⁱⁱ	0.95 (2)	1.79 (2)	2.743 (3)	175 (3)
O3—H3B⋯O1	0.95 (2)	1.80 (2)	2.744 (3)	171 (3)

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Symmetry codes: (i) Inline graphic ; (ii) .

Acknowledgments

This work was supported by a grant from the University of Tehran.

supplementary crystallographic information

Comment

Bidentate ligands containing both hard (nitrogen) and soft (phosphorous) donor atoms are extremely fruitful in both homogenous catalysis and coordination chemistry (Espinet & Soulantica, 1999). Because of having both hard and soft donor atoms, they are called hemilabile ligands (Jeffrey & Rauchfuss, 1979). Diphenylphosphinic acid and its derivatives have been widely used because of their variety of applications. It has been extensively used for extraction of trivalent lanthanide cations and as a flame retardant in epoxy resins that are used in printed circuit boards (Almeida, 1974; Huber, et al., 1998; von Gentzkow, et al., 1996).

The molecular structure of (I) and the atom-numbering scheme are shown in Fig. 1. In this work, attempting to get a new hemilabile bidentate ligand, we obtained pyridinium-2-amine di(phenyl)phosphinate monohydrate, which was unexpectedly produced due to the breaking of P—N bond, probably due to its sensitivity to air and humidity. In the crystal structure, there are three discrete moieties in the asymmetric unit (phosphinic acid, pyridine ring and one water molecule) that are in contact by several hydogen bonds, making a well defined motif. There are also C—H···π interactions between phophinate and pyridinium groups between neighboring motifs. Two P—O bonds are slightly different in distances, (P1—O1 = 1.507 Å and P1—O2 = 1.498 Å), that can be due to the hydrogen bonds between the nitrogen atoms of pyridinium rings to the phosphinate molecules (N1—H1A···O1 and N2—H13···O2, 2.655 (4) and 2.881 (4) Å, respectively, see Table 1). The motifs are in contact by hydrogen bonds in bc plane, making sheets in which these sheets are held together by van der Waals interactions (see Fig. 2 & 3).

Experimental

Synthesis was carried out under argon atmosphere at 0°C, by dropwise addition of neat chlorodiphenylphosphine (3.32 g, 15.04 mmol) to a THF solution of 2-aminopyridine (1.41 g, 15.04 mmol) and triethylamine (1.568 g, 15.5 mmol). The mixture was warmed slowly to room temperature, followed by 24 h stirring. Triethylamine hydrochloride precipitates were then filtered off. Removing the excess solvent under reduced pressure, leads to a pale yellow oily product, that was solidifies by solving in benzene and stored in fridge. The obtained solid (0.100 g, 0.359 mmol) together with stoichiometric quantity of sulfur (0.011 g, 0.359 mmol) in toluene were refluxed for 30 minutes and the resulting solution was dried. Recrystallizing in hot toluene afforded colorless needle crystals.