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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 7| July 2011| Page o1741
doi:10.1107/S1600536811020332

(Iso­propyl­amino)(meth­yl)di­phenyl­phospho­nium iodide

Normen Peulecke,a* Stephan Peitz,a Bernd H. Müller,a Anke Spannenberga and Uwe Rosenthala

aLeibniz-Institut für Katalyse e. V. an der Universität Rostock, Albert-Einstein-Strasse 29A, 18059 Rostock, Germany
*Correspondence e-mail: normen.peulecke@catalysis.de

(Received 4 May 2011; accepted 27 May 2011; online 18 June 2011)

The title compound, C16H21NP+·I−, was obtained by the reaction of Ph2PN(iPr)P(Ph)N(iPr)H with MeI involving cleavage of one of the P—N bonds in diethyl ether. The two phenyl rings form a dihedral angle of 82.98 (5)°. A weak donor–acceptor N—H⋯I inter­action is observed.

Related literature

For the synthesis of Ph2PN(iPr)P(Ph)N(iPr)H, see: Peitz et al. (2010[Peitz, S., Peulecke, N., Aluri, B. R., Hansen, S., Müller, B. H., Spannenberg, A., Rosenthal, U., Al-Hazmi, M. H., Mosa, F. M., Wöhl, A. & Müller, W. (2010). Eur. J. Inorg. Chem. pp. 1167-1171.]). For the structures of amido­phospho­nium salts with similar substituents, see: Payne et al. (1965[Payne, D. S., Mokuolu, J. A. A. & Speakman, J. C. (1965). Chem. Commun. p. 599.]); Imrie et al. (1995[Imrie, C., Modro, T. A., van Rooyen, P. H., Wagener, C. C. P., Wallace, K., Hudson, H. R., McPartlin, M., Nasirun, J. B. & Powroznyk, L. (1995). J. Phys. Org. Chem. 8, 41-46.]); Aladzheva et al. (2003[Aladzheva, I. M., Lobanov, D. I., Bykhovskaya, O. V., Petrovskii, P. V., Lyssenko, K. A. & Mastryukova, T. A. (2003). Heteroat. Chem. 14, 596-602.]); Demange et al. (2006[Demange, M., Boubekeur, L., Auffrant, A., Mezailles, N., Ricard, L., Le Goff, X. & Le Floch, P. (2006). New J. Chem. 30, 1745-1754.]); Mizuta et al. (2007[Mizuta, T., Iwakuni, Y., Nakazano, T., Kubo, K. & Miyoshi, K. (2007). J. Organomet. Chem. 692, 184-193.]).

[Scheme 1]

Experimental

Crystal data

  • C16H21NP+·I−

  • Mr = 385.21

  • Monoclinic, P 21 /n

  • a = 9.0283 (2) Å

  • b = 20.2810 (6) Å

  • c = 9.2298 (3) Å

  • β = 93.492 (2)°

  • V = 1686.87 (8) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 1.98 mm−1

  • T = 150 K

  • 0.45 × 0.30 × 0.16 mm
Data collection

  • Stoe IPDS II diffractometer

  • Absorption correction: numerical (X-SHAPE and X-RED32; Stoe & Cie, 2005[Stoe & Cie (2005). X-SHAPE, X-RED32 and X-AREA. Stoe & Cie, Darmstadt, Germany.]) Tmin = 0.484, Tmax = 0.741

  • 28937 measured reflections

  • 4035 independent reflections

  • 3604 reflections with I > 2σ(I)

  • Rint = 0.024
Refinement

  • R[F2 > 2σ(F2)] = 0.019

  • wR(F2) = 0.048

  • S = 1.05

  • 4035 reflections

  • 179 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.63 e Å−3

  • Δρmin = −0.43 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N1—H1A⋯I1 0.81 (2) 2.88 (2) 3.6641 (15) 164.9 (18)

Data collection: X-AREA (Stoe & Cie, 2005[Stoe & Cie (2005). X-SHAPE, X-RED32 and X-AREA. Stoe & Cie, Darmstadt, Germany.]); cell refinement: X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811020332/ya2139sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811020332/ya2139Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811020332/ya2139Isup3.cml

checkCIF report


Comment top

Amidophosphonium salts are useful precursors for phosphazenes, which are necessary for the aza-Wittig reaction. They can be synthesized by different methods: addition of alkylhalides or methyltriflate to a phosphorus-nitrogen-single bond (Payne et al., 1965; Mizuta et al., 2007), addition of alkylhalides to a phosphorus-nitrogen double bond (Imrie et al., 1995), via intramolecular addition of alkylhalides (Aladzheva et al., 2003) or via other routes (Demange et al., 2006). We became interested in this class of compounds, because the starting compound Ph2PN(iPr)P(Ph)N(iPr)H acts as a superb ligand in the chromium catalyzed trimerization of ethene (Peitz et al., 2010). Here we describe the reaction of this ligand with iodomethane. Surprisingly, it is not the expected phosphonium salt with an intact PNPN-framework, but rather the title compound which is formed in this reaction, due to a cleavage of one of the PN-bonds. The reason for this unusual reaction course is unclear.

Two phenyl rings in the molecule of the title compound form a dihedral angle of 82.98 (5)° (Fig. 1). All angles around the quarternized phosphorus atom are nearly tetrahedral, with the exception of N1—P1—C4 which is significantly widened [115.25 (7)°]. A weak donor-acceptor interaction N1—H1A···I1 [N1—H1A 0.80 (2), H1A···I1 2.88 (2), N1···I1 3.6641 (14) Å, N1—H1A···I1 165.1 (17)°] is observed in the structure.

Related literature top

For the synthesis of Ph2PN(iPr)P(Ph)N(iPr)H, see: Peitz et al. (2010). For the structures of amidophosphonium salts with similar substituents, see: Payne et al. (1965); Imrie et al. (1995); Aladzheva et al. (2003); Demange et al. (2006); Mizuta et al. (2007).

Experimental top

0.062 ml (1.0 mmol) of MeI was added to a stirred solution of 286 mg (0.7 mmol) of Ph2PN(iPr)P(Ph)N(iPr)H in 25 ml of diethylether and the resulting solution was stored at room temperature for 48 h. Subsequently, the white precipitate was filtered off, washed with n-hexane and recrystallized in a dichloromethane/n-hexane mixture to yield 154 mg (0.4 mmol) of colourless crystals of the title compound, which were suitable for X-ray crystal structure analysis and fully characterized by standard analytical methods e.g. 31P NMR: (CD2Cl2): 38,1 p.p.m.

Refinement top

H1A which is attached to N1 was found from difference Fourier map and refined isotropically [N1—H1A 0.81 (2) Å]. All other H atoms were placed in idealized positions with d(C—H) = 0.98 (CH3) and 0.95–1.00 Å (CH) and refined using a riding model with Uiso(H) fixed at 1.5 Ueq(C) for CH3 and 1.2 Ueq(C) for CH.

Computing details top

Data collection: X-AREA (Stoe & Cie, 2005); cell refinement: X-AREA (Stoe & Cie, 2005); data reduction: X-AREA (Stoe & Cie, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound; displacement ellipsoids are drawn at the 30% probability level.
(Isopropylamino)(methyl)diphenylphosphonium iodide top
Crystal data top
C16H21NP+·I−F(000) = 768
Mr = 385.21Dx = 1.517 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 9114 reflections
a = 9.0283 (2) Åθ = 2.0–28.4°
b = 20.2810 (6) ŵ = 1.98 mm−1
c = 9.2298 (3) ÅT = 150 K
β = 93.492 (2)°Prism, colourless
V = 1686.87 (8) Å30.45 × 0.30 × 0.16 mm
Z = 4
Data collection top
Stoe IPDS II
diffractometer		4035 independent reflections
Radiation source: fine-focus sealed tube3604 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.024
ω scansθmax = 27.9°, θmin = 2.0°
Absorption correction: numerical
(X-SHAPE and X-RED32; Stoe & Cie, 2005)		h = −11→11
Tmin = 0.484, Tmax = 0.741k = −26→26
28937 measured reflectionsl = −12→12
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.019Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.048H atoms treated by a mixture of independent and constrained refinement
S = 1.05 w = 1/[σ2(Fo2) + (0.0324P)2 + 0.1321P]
where P = (Fo2 + 2Fc2)/3
4035 reflections(Δ/σ)max = 0.001
179 parametersΔρmax = 0.63 e Å−3
0 restraintsΔρmin = −0.43 e Å−3
Crystal data top
C16H21NP+·I−V = 1686.87 (8) Å3
Mr = 385.21Z = 4
Monoclinic, P21/nMo Kα radiation
a = 9.0283 (2) ŵ = 1.98 mm−1
b = 20.2810 (6) ÅT = 150 K
c = 9.2298 (3) Å0.45 × 0.30 × 0.16 mm
β = 93.492 (2)°
Data collection top
Stoe IPDS II
diffractometer		4035 independent reflections
Absorption correction: numerical
(X-SHAPE and X-RED32; Stoe & Cie, 2005)		3604 reflections with I > 2σ(I)
Tmin = 0.484, Tmax = 0.741Rint = 0.024
28937 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0190 restraints
wR(F2) = 0.048H atoms treated by a mixture of independent and constrained refinement
S = 1.05Δρmax = 0.63 e Å−3
4035 reflectionsΔρmin = −0.43 e Å−3
179 parameters
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
C10.3442 (2)0.76211 (8)0.30748 (19)0.0309 (3)
H1B0.44880.75780.27870.037*
C20.3472 (3)0.78356 (12)0.4653 (2)0.0532 (6)
H2A0.39700.82640.47620.080*
H2B0.40110.75080.52600.080*
H2C0.24540.78740.49550.080*
C30.2667 (2)0.69656 (9)0.2829 (2)0.0404 (4)
H3A0.16160.70120.30190.061*
H3B0.31270.66350.34870.061*
H3C0.27550.68250.18220.061*
C40.36979 (17)0.94492 (8)0.24664 (16)0.0237 (3)
C50.4810 (2)0.99058 (9)0.22218 (18)0.0315 (3)
H50.55040.98200.15110.038*
C60.4901 (2)1.04863 (9)0.3019 (2)0.0355 (4)
H60.56541.08000.28530.043*
C70.3891 (2)1.06068 (9)0.40561 (19)0.0328 (4)
H70.39501.10060.45960.039*
C80.28023 (19)1.01536 (9)0.43122 (18)0.0306 (3)
H80.21241.02390.50370.037*
C90.26912 (18)0.95730 (8)0.35172 (16)0.0267 (3)
H90.19340.92620.36890.032*
C100.23107 (17)0.89557 (8)−0.02177 (16)0.0236 (3)
C110.1988 (2)0.84705 (9)−0.12705 (18)0.0297 (3)
H110.23040.8029−0.11070.036*
C120.1206 (2)0.86407 (10)−0.25494 (18)0.0344 (4)
H120.09850.8315−0.32700.041*
C130.0743 (2)0.92834 (11)−0.27819 (19)0.0368 (4)
H130.02120.9397−0.36670.044*
C140.1045 (2)0.97639 (10)−0.17426 (19)0.0359 (4)
H140.07161.0204−0.19090.043*
C150.18339 (18)0.95991 (9)−0.04522 (17)0.0284 (3)
H150.20460.99260.02670.034*
N10.26667 (16)0.81103 (7)0.21097 (14)0.0255 (3)
P10.34534 (4)0.87284 (2)0.13541 (4)0.02117 (8)
I1−0.103895 (11)0.834024 (5)0.344262 (11)0.02825 (4)
C160.52126 (19)0.84672 (9)0.07819 (19)0.0300 (3)
H16A0.59040.84090.16330.045*
H16B0.56030.88010.01390.045*
H16C0.50970.80480.02600.045*
H1A0.180 (2)0.8158 (10)0.223 (2)0.025 (5)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0332 (9)0.0258 (8)0.0339 (8)0.0029 (7)0.0046 (7)0.0075 (6)
C20.0787 (17)0.0453 (12)0.0337 (10)−0.0003 (11)−0.0116 (10)0.0064 (9)
C30.0504 (12)0.0264 (9)0.0463 (10)−0.0014 (8)0.0172 (9)0.0015 (8)
C40.0234 (7)0.0247 (8)0.0226 (6)−0.0009 (6)−0.0008 (5)0.0017 (6)
C50.0309 (8)0.0349 (9)0.0286 (7)−0.0084 (7)0.0017 (6)0.0007 (7)
C60.0379 (10)0.0307 (9)0.0371 (9)−0.0119 (7)−0.0042 (7)0.0037 (7)
C70.0384 (10)0.0247 (8)0.0339 (8)0.0015 (7)−0.0104 (7)−0.0020 (7)
C80.0289 (8)0.0313 (9)0.0311 (8)0.0052 (6)−0.0021 (6)−0.0035 (6)
C90.0253 (8)0.0273 (8)0.0276 (7)−0.0003 (6)0.0018 (6)−0.0009 (6)
C100.0201 (7)0.0284 (8)0.0224 (7)−0.0004 (6)0.0027 (5)0.0018 (6)
C110.0298 (8)0.0302 (8)0.0290 (8)−0.0023 (6)0.0026 (6)−0.0022 (6)
C120.0296 (9)0.0466 (11)0.0269 (8)−0.0069 (8)0.0019 (6)−0.0039 (7)
C130.0275 (9)0.0555 (12)0.0272 (8)−0.0006 (8)−0.0007 (6)0.0089 (7)
C140.0314 (9)0.0403 (10)0.0360 (9)0.0068 (7)0.0016 (7)0.0105 (7)
C150.0268 (8)0.0301 (8)0.0285 (7)0.0010 (6)0.0031 (6)0.0017 (6)
N10.0217 (7)0.0265 (7)0.0287 (6)−0.0002 (5)0.0044 (5)0.0031 (5)
P10.01969 (18)0.02299 (19)0.02100 (16)0.00007 (14)0.00262 (13)0.00071 (13)
I10.02589 (6)0.02866 (7)0.03035 (6)−0.00158 (4)0.00287 (4)−0.00291 (4)
C160.0237 (8)0.0349 (9)0.0319 (8)0.0047 (6)0.0067 (6)0.0020 (7)
Geometric parameters (Å, º) top
C1—N11.481 (2)C8—H80.9500
C1—C31.513 (3)C9—H90.9500
C1—C21.519 (3)C10—C151.387 (2)
C1—H1B1.0000C10—C111.401 (2)
C2—H2A0.9800C10—P11.7886 (15)
C2—H2B0.9800C11—C121.382 (2)
C2—H2C0.9800C11—H110.9500
C3—H3A0.9800C12—C131.381 (3)
C3—H3B0.9800C12—H120.9500
C3—H3C0.9800C13—C141.383 (3)
C4—C91.392 (2)C13—H130.9500
C4—C51.394 (2)C14—C151.391 (2)
C4—P11.7922 (16)C14—H140.9500
C5—C61.388 (3)C15—H150.9500
C5—H50.9500N1—P11.6195 (15)
C6—C71.383 (3)N1—H1A0.81 (2)
C6—H60.9500P1—C161.7845 (17)
C7—C81.377 (3)C16—H16A0.9800
C7—H70.9500C16—H16B0.9800
C8—C91.388 (2)C16—H16C0.9800
N1—C1—C3107.52 (15)C4—C9—H9120.3
N1—C1—C2111.42 (15)C15—C10—C11120.21 (15)
C3—C1—C2112.10 (16)C15—C10—P1121.82 (12)
N1—C1—H1B108.6C11—C10—P1117.82 (13)
C3—C1—H1B108.6C12—C11—C10119.39 (17)
C2—C1—H1B108.6C12—C11—H11120.3
C1—C2—H2A109.5C10—C11—H11120.3
C1—C2—H2B109.5C13—C12—C11120.15 (17)
H2A—C2—H2B109.5C13—C12—H12119.9
C1—C2—H2C109.5C11—C12—H12119.9
H2A—C2—H2C109.5C12—C13—C14120.82 (16)
H2B—C2—H2C109.5C12—C13—H13119.6
C1—C3—H3A109.5C14—C13—H13119.6
C1—C3—H3B109.5C13—C14—C15119.58 (18)
H3A—C3—H3B109.5C13—C14—H14120.2
C1—C3—H3C109.5C15—C14—H14120.2
H3A—C3—H3C109.5C10—C15—C14119.85 (16)
H3B—C3—H3C109.5C10—C15—H15120.1
C9—C4—C5120.01 (15)C14—C15—H15120.1
C9—C4—P1118.91 (12)C1—N1—P1125.03 (12)
C5—C4—P1120.91 (13)C1—N1—H1A115.3 (14)
C6—C5—C4119.83 (17)P1—N1—H1A115.0 (14)
C6—C5—H5120.1N1—P1—C16108.61 (8)
C4—C5—H5120.1N1—P1—C10107.60 (7)
C7—C6—C5119.77 (17)C16—P1—C10108.44 (8)
C7—C6—H6120.1N1—P1—C4115.25 (7)
C5—C6—H6120.1C16—P1—C4109.32 (8)
C8—C7—C6120.56 (16)C10—P1—C4107.41 (7)
C8—C7—H7119.7P1—C16—H16A109.5
C6—C7—H7119.7P1—C16—H16B109.5
C7—C8—C9120.33 (17)H16A—C16—H16B109.5
C7—C8—H8119.8P1—C16—H16C109.5
C9—C8—H8119.8H16A—C16—H16C109.5
C8—C9—C4119.49 (16)H16B—C16—H16C109.5
C8—C9—H9120.3
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···I10.81 (2)2.88 (2)3.6641 (15)164.9 (18)

Experimental details

Crystal data
Chemical formulaC16H21NP+·I−
Mr385.21
Crystal system, space groupMonoclinic, P21/n
Temperature (K)150
a, b, c (Å)9.0283 (2), 20.2810 (6), 9.2298 (3)
β (°) 93.492 (2)
V (Å3)1686.87 (8)
Z4
Radiation typeMo Kα
µ (mm−1)1.98
Crystal size (mm)0.45 × 0.30 × 0.16
Data collection
DiffractometerStoe IPDS II
diffractometer
Absorption correctionNumerical
(X-SHAPE and X-RED32; Stoe & Cie, 2005)
Tmin, Tmax0.484, 0.741
No. of measured, independent and
observed [I > 2σ(I)] reflections		28937, 4035, 3604
Rint0.024
(sin θ/λ)max (Å−1)0.658
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.019, 0.048, 1.05
No. of reflections4035
No. of parameters179
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.63, −0.43

Computer programs: X-AREA (Stoe & Cie, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···I10.81 (2)2.88 (2)3.6641 (15)164.9 (18)
 

Acknowledgements

This work was supported by the Leibniz-Institut für Katalyse e·V. an der Universität Rostock.

References

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Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 67| Part 7| July 2011| Page o1741
doi:10.1107/S1600536811020332
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