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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 2| February 2011| Page o311
doi:10.1107/S1600536810054401

Tetra­kis(benzyl­amino)­phospho­nium chloride

Khodayar Gholivand,a* Hossein Mostaanzadeha and Sedigheh Farshadiana

aDepartment of Chemistry, Tarbiat Modares University, Tehran, 14115/175, Iran
*Correspondence e-mail: gholi_kh@modares.ac.ir

(Received 22 November 2010; accepted 27 December 2010; online 8 January 2011)

The title salt, [P(NHCH2C6H5)4]+·Cl−, crystallizes with the P atom and Cl− anion lying on a twofold rotation axis. The P atom has a slightly distorted tetra­hedral geometry with two classes of N—P—N angles [101.15 (10) and 100.55 (11)° and 113.07 (9) and 114.83 (8)°] and the environments of sp2-hybridized N atoms are essentially planar (sum of angles = 359.9 and 360.1°). In the crystal, the phospho­nium ion inter­acts with each neighboring chloride ion via two approximately equal N—H⋯Cl inter­actions, forming parallel chains along the c axis.

Related literature

For background information on phospho­nium salts, see: Hart & Sisler (1964[Hart, W. A. & Sisler, H. H. (1964). Inorg. Chem. 3, 617-622.]); Levason et al. (2006[Levason, W., Reid, G. & Webster, M. (2006). Acta Cryst. C62, o438-o440.]); Schiemenz et al. (2003[Schiemenz, B., Wessel, T. & Pfirmann, R. (2003). US Patent No. 6 645 904.]). For related structures, see: Bickley et al. (2004[Bickley, J. F., Copsey, M. C., Jeffery, J. C., Leedham, A. P., Russell, C. A., Stalke, D., Steiner, A., Stey, T. & Zacchini, S. (2004). Dalton Trans. pp. 989-995.]); Horstmann & Schnick (1996[Horstmann, S. & Schnick, W. (1996). Z. Naturforsch. Teil B, 51, 127-132.])

[Scheme 1]

Experimental

Crystal data

  • C28H32N4P+·Cl−

  • Mr = 491.00

  • Orthorhombic, P 21 21 2

  • a = 11.359 (3) Å

  • b = 14.258 (4) Å

  • c = 7.923 (3) Å

  • V = 1283.1 (6) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.24 mm−1

  • T = 193 K

  • 0.50 × 0.40 × 0.25 mm
Data collection

  • Rebuilt Syntex P21/Siemens P3 four-circle diffractometer

  • 6760 measured reflections

  • 3122 independent reflections

  • 2677 reflections with I > 2σ(I)

  • Rint = 0.024

  • 2 standard reflections every 98 reflections intensity decay: 2%
Refinement

  • R[F2 > 2σ(F2)] = 0.036

  • wR(F2) = 0.094

  • S = 1.01

  • 3122 reflections

  • 155 parameters

  • H-atom parameters constrained

  • Δρmax = 0.35 e Å−3

  • Δρmin = −0.33 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1321 Friedel pairs

  • Flack parameter: 0.08 (8)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N1—H1C⋯Cl1i 0.86 2.35 3.1848 (17) 163
N2—H2A⋯Cl1 0.86 2.35 3.1855 (18) 165
Symmetry code: (i) x, y, z-1.

Data collection: P3/PC (Siemens, 1989[Siemens (1989). P3/PC. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); cell refinement: P3/PC; data reduction: P3/PC; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL and Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810054401/nk2077sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810054401/nk2077Isup2.hkl

checkCIF report


Comment top

Phosphonium salts, [PR4]+, are widely used as large cations to stabilize a variety of anionic species and to phase-transfer anions into low polarity organic media (Levason et al., 2006). A few examples of tetraamino phosphonium salts exist in the literature (Hart & Sisler, 1964) and some of them are used as catalysis for preparing fluorine-containing compounds by a halogen/fluorine exchange reaction (Schiemenz et al., 2003). Also, the crystal structure of P(NH2)4Cl (Horstmann & Schnick, 1996) and [P(NHPh)4]Cl (Bickley et al., 2004) have been reported. In an effort to further investigation into these types of compounds, the crystal structure of [P(NHCH2C6H5)4]+.Cl- is presented.

The title salt, [P(NHCH2C6H5)4]+.Cl-, crystallizes with the P atom and Cl- anion lying on a two-fold rotation axis in the space group P21212. The supramolecular structure of compound exhibits a polymeric chain of alternating phosphonium and chloride ions in the solid state (Fig. 2) with P···P distances of 7.923 Å. The phosphonium ion interacts with each neighboring chloride ion via two equal N—H···Cl interactions and six-membered rings around each phosphorus atom are formed. The centroid–centroid distance between adjacent phenyl rings is 4.009 Å, indicating no strong π–π stacking interactions exist in compound.

The four P–N bonds are of almost equal lengths 1.6166 (14) and 1.6184 (14) Å and are similar to those found in [P(NHPh)4]Cl (Bickley et al., 2004) and P(NH2)4Cl (Horstmann & Schnick, 1996). These P–N bonds are shorter than the typical P–N single bond length (1.77 Å) . As observed in [P(NHPh)4]Cl, there are two classes of N–P–N angles resulting in a distorted tetrahedral environment for P1. More acute angles of 101.15 (10) and 100.55° are observed within the hydrogen bonding chelates of the N1–P1–N1iand N2–P1–N2i (i: -x, -y, z) units respectively, whereas the remaining four N–P–N angles are 113.07 (9) and 114.83 (8)°. Although the main cause for the distortion from the ideal tetrahedral geometry is unclear, it seems to be partly controlled by hydrogen bonding. The sum of angles around nitrogen atoms are exactly 360° and these atoms are sp2 hybridized.

Related literature top

For background information on phosphonium salts, see: Hart & Sisler (1964); Levason et al. (2006); Schiemenz et al. (2003). For related structures, see: Bickley et al. (2004); Horstmann & Schnick (1996)

Experimental top

All the reagents and solvents were used as obtained without further purification. Phosphorus pentachloride (2 mmol) was added drop wise with constant stirring to a toluene solution (30 ml) of benzylamine (8 mmol) at 0°C. After an hour stirring, the reaction mixture was refluxed for 3 h. The solid formed during the reaction was filtered and then washed with distilled water, toluene, chloroform and dried. Single crystals suitable for single-crystal X-ray diffraction analysis were obtained from the mixture of MeOH and CH3CN solution.

Refinement top

The hydrogen atoms of NH groups were found in difference Fourier synthesis, the H(C) atom positions were calculated. All hydrogen atoms were refined in isotropic approximatiom in riding model with with the Uiso(H) parameters equal to 1.2 Ueq(X), where U(X) are the equivalent thermal parameters of the atoms to which corresponding H atoms are bonded. The absolute structure parameter (Flack, 1983) is refined based on 1321 Friedel pairs.

Computing details top

Data collection: P3/PC (Siemens, 1989); cell refinement: P3/PC (Siemens, 1989); data reduction: P3/PC (Siemens, 1989); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The structure of the title compound with 50% displacement ellipsoids and C-bound H atoms omitted. Unlabeled atoms are related to labeled atoms by a two-fold rotation.
[Figure 2] Fig. 2. An a-axis projection showing hydrogen bonding dotted lines. The long b axis is truncated.
Tetrakis(benzylamino)phosphonium chloride top
Crystal data top
C28H32N4P+·Cl−F(000) = 520
Mr = 491.00Dx = 1.271 Mg m−3
Orthorhombic, P21212Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2 2abCell parameters from 24 reflections
a = 11.359 (3) Åθ = 10–11°
b = 14.258 (4) ŵ = 0.24 mm−1
c = 7.923 (3) ÅT = 193 K
V = 1283.1 (6) Å3Plate, colourless
Z = 20.50 × 0.40 × 0.25 mm
Data collection top
Rebuilt Syntex P21/Siemens P3 four-circle
diffractometer		Rint = 0.024
Radiation source: fine-focus sealed tubeθmax = 28.1°, θmin = 2.3°
Graphite monochromatorh = −15→15
θ/2θ scansk = −18→18
6760 measured reflectionsl = −10→10
3122 independent reflections2 standard reflections every 98 reflections
2677 reflections with I > 2σ(I) intensity decay: 2%
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.036H-atom parameters constrained
wR(F2) = 0.094 w = 1/[σ2(Fo2) + (0.0604P)2 + 0.1221P]
where P = (Fo2 + 2Fc2)/3
S = 1.01(Δ/σ)max = 0.001
3122 reflectionsΔρmax = 0.35 e Å−3
155 parametersΔρmin = −0.33 e Å−3
0 restraintsAbsolute structure: Flack (1983), 1321 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.08 (8)
Crystal data top
C28H32N4P+·Cl−V = 1283.1 (6) Å3
Mr = 491.00Z = 2
Orthorhombic, P21212Mo Kα radiation
a = 11.359 (3) ŵ = 0.24 mm−1
b = 14.258 (4) ÅT = 193 K
c = 7.923 (3) Å0.50 × 0.40 × 0.25 mm
Data collection top
Rebuilt Syntex P21/Siemens P3 four-circle
diffractometer		Rint = 0.024
6760 measured reflections2 standard reflections every 98 reflections
3122 independent reflections intensity decay: 2%
2677 reflections with I > 2σ(I)
Refinement top
R[F2 > 2σ(F2)] = 0.036H-atom parameters constrained
wR(F2) = 0.094Δρmax = 0.35 e Å−3
S = 1.01Δρmin = −0.33 e Å−3
3122 reflectionsAbsolute structure: Flack (1983), 1321 Friedel pairs
155 parametersAbsolute structure parameter: 0.08 (8)
0 restraints
Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cl10.00000.00000.67845 (6)0.03585 (15)
P10.00000.00000.17782 (6)0.02407 (13)
N10.08364 (13)0.05683 (9)0.04823 (17)0.0305 (3)
H1C0.06840.0528−0.05780.037*
N2−0.07306 (14)0.06507 (10)0.30836 (17)0.0347 (3)
H2A−0.06230.05600.41460.042*
C10.18316 (15)0.11449 (11)0.0998 (2)0.0327 (4)
H1A0.24870.10160.02480.039*
H1B0.20670.09580.21250.039*
C20.16072 (13)0.21915 (10)0.1000 (2)0.0255 (3)
C30.06933 (14)0.25994 (12)0.0093 (2)0.0309 (3)
H3A0.01930.2226−0.05480.037*
C40.05265 (16)0.35639 (13)0.0142 (3)0.0396 (4)
H4A−0.00900.3832−0.04610.047*
C50.12664 (17)0.41274 (12)0.1078 (3)0.0435 (5)
H5A0.11420.47720.11200.052*
C60.21920 (16)0.37315 (12)0.1953 (3)0.0394 (4)
H6A0.27030.41110.25640.047*
C70.23623 (14)0.27655 (11)0.1922 (2)0.0301 (3)
H7A0.29840.25020.25200.036*
C8−0.15598 (16)0.13807 (12)0.2581 (2)0.0342 (4)
H8A−0.23550.11600.27870.041*
H8B−0.14800.14910.13790.041*
C9−0.13829 (14)0.22969 (11)0.3506 (2)0.0265 (3)
C10−0.03555 (14)0.25145 (12)0.4376 (2)0.0311 (3)
H10A0.02480.20750.44370.037*
C11−0.02213 (15)0.33760 (13)0.5152 (3)0.0392 (4)
H11A0.04720.35140.57250.047*
C12−0.11172 (17)0.40365 (12)0.5081 (3)0.0419 (4)
H12A−0.10240.46170.55970.050*
C13−0.21480 (16)0.38267 (12)0.4238 (3)0.0374 (4)
H13A−0.27520.42660.41910.045*
C14−0.22821 (14)0.29623 (12)0.3465 (2)0.0317 (3)
H14A−0.29820.28240.29090.038*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0282 (3)0.0634 (4)0.0159 (2)−0.0003 (3)0.0000.000
P10.0382 (3)0.0190 (2)0.0151 (2)0.0001 (2)0.0000.000
N10.0447 (8)0.0280 (6)0.0188 (6)−0.0127 (6)−0.0030 (6)−0.0009 (5)
N20.0570 (9)0.0301 (6)0.0169 (6)0.0133 (7)0.0002 (6)−0.0021 (5)
C10.0334 (8)0.0262 (7)0.0387 (9)−0.0025 (6)−0.0071 (7)−0.0007 (7)
C20.0281 (7)0.0251 (7)0.0234 (7)−0.0037 (6)0.0038 (6)−0.0003 (6)
C30.0296 (7)0.0322 (8)0.0309 (8)−0.0019 (6)−0.0011 (6)−0.0003 (7)
C40.0343 (8)0.0371 (9)0.0473 (11)0.0062 (7)0.0032 (8)0.0078 (8)
C50.0431 (10)0.0251 (8)0.0624 (13)−0.0012 (7)0.0105 (9)0.0014 (8)
C60.0394 (9)0.0304 (8)0.0483 (11)−0.0120 (7)0.0038 (9)−0.0070 (8)
C70.0288 (7)0.0311 (8)0.0305 (8)−0.0046 (6)0.0020 (7)−0.0007 (7)
C80.0399 (9)0.0340 (8)0.0288 (8)0.0069 (7)−0.0046 (7)−0.0056 (7)
C90.0297 (7)0.0273 (7)0.0225 (8)0.0029 (6)0.0037 (6)0.0023 (6)
C100.0258 (7)0.0320 (7)0.0354 (8)0.0049 (6)0.0031 (7)−0.0015 (7)
C110.0277 (8)0.0379 (9)0.0520 (11)−0.0061 (7)0.0008 (8)−0.0068 (8)
C120.0424 (10)0.0238 (8)0.0595 (12)−0.0031 (7)0.0106 (9)−0.0052 (8)
C130.0357 (9)0.0284 (8)0.0481 (11)0.0093 (7)0.0061 (8)0.0055 (7)
C140.0299 (7)0.0330 (8)0.0323 (9)0.0064 (6)−0.0019 (7)0.0041 (7)
Geometric parameters (Å, º) top
P1—N1i1.6166 (14)C5—H5A0.9300
P1—N11.6166 (14)C6—C71.391 (2)
P1—N2i1.6184 (14)C6—H6A0.9300
P1—N21.6184 (14)C7—H7A0.9300
N1—C11.456 (2)C8—C91.511 (2)
N1—H1C0.8600C8—H8A0.9700
N2—C81.459 (2)C8—H8B0.9700
N2—H2A0.8600C9—C101.391 (2)
C1—C21.514 (2)C9—C141.395 (2)
C1—H1A0.9700C10—C111.382 (3)
C1—H1B0.9700C10—H10A0.9300
C2—C31.390 (2)C11—C121.388 (3)
C2—C71.393 (2)C11—H11A0.9300
C3—C41.389 (3)C12—C131.380 (3)
C3—H3A0.9300C12—H12A0.9300
C4—C51.379 (3)C13—C141.385 (2)
C4—H4A0.9300C13—H13A0.9300
C5—C61.380 (3)C14—H14A0.9300
N1i—P1—N1101.15 (10)C5—C6—C7120.14 (17)
N1i—P1—N2i114.83 (8)C5—C6—H6A119.9
N1—P1—N2i113.07 (9)C7—C6—H6A119.9
N1i—P1—N2113.07 (9)C6—C7—C2120.37 (17)
N1—P1—N2114.83 (8)C6—C7—H7A119.8
N2i—P1—N2100.55 (11)C2—C7—H7A119.8
C1—N1—P1124.13 (12)N2—C8—C9113.49 (14)
C1—N1—H1C117.9N2—C8—H8A108.9
P1—N1—H1C117.9C9—C8—H8A108.9
C8—N2—P1124.45 (12)N2—C8—H8B108.9
C8—N2—H2A117.8C9—C8—H8B108.9
P1—N2—H2A117.8H8A—C8—H8B107.7
N1—C1—C2115.22 (14)C10—C9—C14118.34 (15)
N1—C1—H1A108.5C10—C9—C8123.02 (14)
C2—C1—H1A108.5C14—C9—C8118.64 (15)
N1—C1—H1B108.5C11—C10—C9120.76 (15)
C2—C1—H1B108.5C11—C10—H10A119.6
H1A—C1—H1B107.5C9—C10—H10A119.6
C3—C2—C7119.02 (14)C10—C11—C12120.27 (17)
C3—C2—C1122.52 (14)C10—C11—H11A119.9
C7—C2—C1118.45 (15)C12—C11—H11A119.9
C4—C3—C2120.11 (16)C13—C12—C11119.65 (16)
C4—C3—H3A119.9C13—C12—H12A120.2
C2—C3—H3A119.9C11—C12—H12A120.2
C5—C4—C3120.59 (17)C12—C13—C14120.01 (16)
C5—C4—H4A119.7C12—C13—H13A120.0
C3—C4—H4A119.7C14—C13—H13A120.0
C4—C5—C6119.74 (16)C13—C14—C9120.96 (16)
C4—C5—H5A120.1C13—C14—H14A119.5
C6—C5—H5A120.1C9—C14—H14A119.5
N1i—P1—N1—C1−174.86 (17)C5—C6—C7—C20.5 (3)
N2i—P1—N1—C1−51.55 (15)C3—C2—C7—C61.0 (2)
N2—P1—N1—C163.05 (15)C1—C2—C7—C6179.71 (17)
N1i—P1—N2—C8−56.69 (16)P1—N2—C8—C9−132.58 (14)
N1—P1—N2—C858.69 (17)N2—C8—C9—C1017.1 (2)
N2i—P1—N2—C8−179.61 (19)N2—C8—C9—C14−163.97 (15)
P1—N1—C1—C2−101.97 (17)C14—C9—C10—C11−1.2 (3)
N1—C1—C2—C3−19.8 (2)C8—C9—C10—C11177.70 (17)
N1—C1—C2—C7161.45 (15)C9—C10—C11—C120.4 (3)
C7—C2—C3—C4−1.4 (2)C10—C11—C12—C130.4 (3)
C1—C2—C3—C4179.90 (17)C11—C12—C13—C14−0.3 (3)
C2—C3—C4—C50.4 (3)C12—C13—C14—C9−0.6 (3)
C3—C4—C5—C61.0 (3)C10—C9—C14—C131.4 (2)
C4—C5—C6—C7−1.5 (3)C8—C9—C14—C13−177.61 (16)
Symmetry code: (i) −x, −y, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1C···Cl1ii0.862.353.1848 (17)163
N2—H2A···Cl10.862.353.1855 (18)165
Symmetry code: (ii) x, y, z−1.

Experimental details

Crystal data
Chemical formulaC28H32N4P+·Cl−
Mr491.00
Crystal system, space groupOrthorhombic, P21212
Temperature (K)193
a, b, c (Å)11.359 (3), 14.258 (4), 7.923 (3)
V (Å3)1283.1 (6)
Z2
Radiation typeMo Kα
µ (mm−1)0.24
Crystal size (mm)0.50 × 0.40 × 0.25
Data collection
DiffractometerRebuilt Syntex P21/Siemens P3 four-circle
diffractometer
Absorption correction–
No. of measured, independent and
observed [I > 2σ(I)] reflections		6760, 3122, 2677
Rint0.024
(sin θ/λ)max (Å−1)0.662
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.036, 0.094, 1.01
No. of reflections3122
No. of parameters155
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.35, −0.33
Absolute structureFlack (1983), 1321 Friedel pairs
Absolute structure parameter0.08 (8)

Computer programs: P3/PC (Siemens, 1989), SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1C···Cl1i0.862.353.1848 (17)163
N2—H2A···Cl10.862.353.1855 (18)165
Symmetry code: (i) x, y, z−1.
 

Acknowledgements

The authors acknowledge Tarbiat Modares University for financial support.

References

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 First citationFlack, H. D. (1983). Acta Cryst. A39, 876–881.  CrossRef CAS Web of Science IUCr Journals Google Scholar
 First citationHart, W. A. & Sisler, H. H. (1964). Inorg. Chem. 3, 617–622.  CrossRef CAS Web of Science Google Scholar
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ISSN: 2056-9890
Volume 67| Part 2| February 2011| Page o311
doi:10.1107/S1600536810054401
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