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Acta Crystallogr Sect E Struct Rep Online. 2010 June 1; 66(Pt 6): o1270.
Published online 2010 May 8. doi:  10.1107/S1600536810015886
PMCID: PMC2979499

1,2-Bis(diphenyl­phosphino)-1,2-diethyl­hydrazine

Abstract

The title compound, C28H30N2P2, adopts a well documented and studied gauche conformation around the hydrazine bond. Bond lengths and angles are in the typical ranges expected for P—N and P—C bonds. A normal hydrazine N—N bond length of 1.426 (3) Å is observed.

Related literature

For related structures, see: Reddy et al. (1994 [triangle], 1995 [triangle]); Pelizzi & Pelizzi (1979 [triangle]). For ab initio mol­ecular modelling studies, see: Cowley et al. (1979 [triangle]).

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Object name is e-66-o1270-scheme1.jpg

Experimental

Crystal data

  • C28H30N2P2
  • M r = 456.48
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o1270-efi1.jpg
  • a = 14.623 (5) Å
  • b = 13.085 (4) Å
  • c = 13.494 (4) Å
  • β = 108.182 (6)°
  • V = 2453.1 (13) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.20 mm−1
  • T = 173 K
  • 0.44 × 0.17 × 0.17 mm

Data collection

  • Bruker SMART 1K CCD area-detector diffractometer
  • 15744 measured reflections
  • 6008 independent reflections
  • 3774 reflections with I > 2σ(I)
  • R int = 0.056

Refinement

  • R[F 2 > 2σ(F 2)] = 0.058
  • wR(F 2) = 0.156
  • S = 1.02
  • 6008 reflections
  • 289 parameters
  • H-atom parameters constrained
  • Δρmax = 0.82 e Å−3
  • Δρmin = −0.56 e Å−3

Data collection: SMART-NT (Bruker, 1998 [triangle]); cell refinement: SAINT-Plus (Bruker, 1999 [triangle]); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 (Farrugia, 1997 [triangle]) and Mercury (Macrae et al., 2008 [triangle]); software used to prepare material for publication: WinGX (Farrugia, 1999 [triangle]).

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810015886/wn2384sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810015886/wn2384Isup2.hkl

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

Acknowledgments

The authors thank Project AuTEK (Mintek and Harmony) and the University of the Witwatersrand for financial support.

supplementary crystallographic information

Comment

Crystals of the title compound (Fig. 1) are found to be monoclinic, crystallising in the space group P21/c. Crystals of 1,2-bis(diphenylphosphino)ethane (dppe) show similar characteristics; it is monoclinic and crystallises in the spacegroup P21/n (Pelizzi et al., 1979). The title compound has four molecules per unit cell compared to two in dppe; the latter has a centre of symmetry at the mid-point of the C(sp3)—C(sp3) bond.

Dppe was shown to adopt a staggered conformation, whereas the title compound has a gauche conformation. This gauche conformation adopted by hydrazine has been well documented and studied both experimentally and by ab anitio molecular modelling (Cowley et al., 1979). It was found that the ground-state geometry of hydrazine is gauche, with a dihedral angle close to 90°. Ab initio theoretical estimates of the gauche-anti and gauche-syn barrier heights fall in the ranges 1.6-6.2 and 9.7-13.7 kcal/mol, respectively. In hydrazine, the relative stability of the conformations are gauche > anti > syn (Cowley et al., 1979). The planar conformation of dppe allows it to form stacks of molecules; this is not possible for the title compound.

Bond lengths and angles are in the typical ranges expected for P—N and P—C bonds (Reddy et al., 1994). A normal hydrazine N—N bond length of 1.426 (3) Å is observed.

Experimental

The title compound was synthesised in a similar manner to published methods (Reddy et al. 1994, 1995). The compound was obtained as light yellow, single crystalline flakes from the worked-up diethylether layer. The diethylether layer was concentrated and kept at -20 °C for 1-3 days. The supernatant was removed from the crystalline flakes and placed back in the freezer for further crystallisation. 86% yield. Mp 95-96 °C.

Refinement

The H atoms were positioned geometrically and allowed to ride on their respective parent atoms, with C—H = 0.93 (Ar-H) or 0.96 (CH3) Å, and with Ueq = 1.2 (Ar-H) or 1.5 (CH3)Ueq(C).

Figures

Fig. 1.
Molecular structure of the title compound, drawn with displacement ellipsoids at the 50% probability level. Hydrogen atoms have been omitted for clarity.

Crystal data

C28H30N2P2Z = 4
Mr = 456.48F(000) = 968
Monoclinic, P21/cDx = 1.236 Mg m3
Hall symbol: -P 2ybcMelting point: 368 K
a = 14.623 (5) ÅMo Kα radiation, λ = 0.71073 Å
b = 13.085 (4) ŵ = 0.20 mm1
c = 13.494 (4) ÅT = 173 K
β = 108.182 (6)°Prismic, colourless
V = 2453.1 (13) Å30.44 × 0.17 × 0.17 mm

Data collection

Bruker SMART 1K CCD area-detector diffractometer3774 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.056
graphiteθmax = 28.3°, θmin = 1.5°
phi and ω scansh = −17→19
15744 measured reflectionsk = −13→17
6008 independent reflectionsl = −17→14

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.058Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.156H-atom parameters constrained
S = 1.02w = 1/[σ2(Fo2) + (0.0731P)2 + 1.0514P] where P = (Fo2 + 2Fc2)/3
6008 reflections(Δ/σ)max = 0.001
289 parametersΔρmax = 0.82 e Å3
0 restraintsΔρmin = −0.56 e Å3

Special details

Experimental. 1HNMR (CDCl3, 300 MHz) δH 7.54 (bs, Arom, 4H) 7.36 (bs, Arom, 4H), 7.26 (m, Arom,12H), 3.73 and 3.23(m, CH2CH3,4H), 0.79 (t, CH2CH3,3J (1H-1H) = 7.0 Hz, 6H). 13C NMR (CDCl3, 75 MHz) δC 140.2 (m, Arom), 133.4 (m, Arom), 131.4 (s, Arom), 128.7(s, Arom), 48.7 (t, CH2CH3, 2J (13C-31P) = 2.5 Hz), 14.3 (d, CH2CH3, 3J (13C-31P) = 4.1 Hz). 31P NMR (CDCl3,162 MHz) δP 63.4. MS 427 (9%, M – 1). Intensity data were collected on a Bruker SMART1K CCD area detector diffractometer with graphite monochromated Mo Kα radiation (40kV, 40mA). The collection method involved ω-scans of width 0.3°.
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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)

xyzUiso*/Ueq
C10.86723 (18)0.1568 (2)0.1440 (2)0.0281 (6)
H1A0.91830.20550.17450.034*
H1B0.83750.17590.07160.034*
C20.9114 (2)0.0518 (2)0.1476 (3)0.0393 (7)
H2A0.95770.05290.11050.059*
H2B0.86180.00320.11570.059*
H2C0.94260.03280.21890.059*
C30.62250 (18)0.1538 (2)0.1085 (2)0.0281 (6)
H3A0.60620.19450.16070.034*
H3B0.57180.10370.08210.034*
C40.6258 (2)0.2228 (2)0.0199 (2)0.0398 (7)
H4A0.56460.2558−0.00880.060*
H4B0.63990.1829−0.03320.060*
H4C0.67490.27350.04560.060*
C110.81426 (17)0.36831 (18)0.27049 (19)0.0227 (5)
C120.81650 (19)0.44196 (19)0.3461 (2)0.0288 (6)
H120.81090.42150.40990.035*
C130.8268 (2)0.5447 (2)0.3280 (2)0.0351 (7)
H130.82860.59240.37960.042*
C140.8345 (2)0.5768 (2)0.2334 (2)0.0351 (7)
H140.84250.64570.22150.042*
C150.8303 (2)0.5057 (2)0.1571 (2)0.0364 (7)
H150.83440.52720.09290.044*
C160.8199 (2)0.4023 (2)0.1743 (2)0.0309 (6)
H160.81680.35540.12160.037*
C210.92822 (18)0.21580 (18)0.39268 (19)0.0236 (5)
C221.00751 (19)0.2724 (2)0.3876 (2)0.0279 (6)
H220.99950.32220.33630.034*
C231.0980 (2)0.2556 (2)0.4579 (2)0.0320 (6)
H231.15050.29260.45250.038*
C241.1104 (2)0.1838 (2)0.5361 (2)0.0358 (7)
H241.17110.17350.58400.043*
C251.0331 (2)0.1275 (2)0.5431 (2)0.0386 (7)
H251.04160.07920.59580.046*
C260.9424 (2)0.1428 (2)0.4716 (2)0.0314 (6)
H260.89060.10410.47640.038*
C310.60617 (19)−0.01800 (19)0.2575 (2)0.0257 (5)
C320.6057 (2)0.0375 (2)0.3455 (2)0.0409 (8)
H320.65910.07660.38050.049*
C330.5265 (3)0.0351 (2)0.3814 (3)0.0503 (9)
H330.52710.07350.43960.060*
C340.4471 (2)−0.0231 (2)0.3320 (2)0.0401 (7)
H340.3944−0.02450.35670.048*
C350.44666 (19)−0.0794 (2)0.2454 (2)0.0334 (6)
H350.3937−0.11990.21190.040*
C360.52481 (18)−0.0760 (2)0.2081 (2)0.0299 (6)
H360.5229−0.11330.14880.036*
C410.68240 (17)−0.10439 (18)0.1100 (2)0.0233 (5)
C420.67952 (19)−0.20902 (19)0.1322 (2)0.0299 (6)
H420.6948−0.23030.20120.036*
C430.6543 (2)−0.2810 (2)0.0532 (2)0.0353 (7)
H430.6526−0.34990.06950.042*
C440.63169 (19)−0.2509 (2)−0.0500 (2)0.0359 (7)
H440.6137−0.2992−0.10310.043*
C450.6360 (2)−0.1489 (2)−0.0735 (2)0.0330 (6)
H450.6217−0.1285−0.14270.040*
C460.66139 (18)−0.07618 (19)0.0055 (2)0.0271 (6)
H460.6644−0.0077−0.01150.033*
N10.79504 (14)0.16499 (15)0.19838 (16)0.0237 (5)
N20.71357 (14)0.09995 (15)0.15842 (16)0.0229 (5)
P10.80362 (5)0.23470 (5)0.30655 (5)0.02321 (17)
P20.71714 (5)−0.01492 (5)0.21993 (5)0.02383 (17)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.0266 (13)0.0350 (15)0.0259 (14)−0.0074 (11)0.0127 (11)−0.0080 (11)
C20.0296 (15)0.0451 (18)0.0467 (19)0.0033 (13)0.0168 (14)−0.0038 (14)
C30.0241 (13)0.0261 (13)0.0317 (15)0.0017 (10)0.0052 (11)0.0013 (11)
C40.0381 (17)0.0316 (16)0.0414 (18)−0.0010 (13)0.0001 (14)0.0093 (13)
C110.0218 (12)0.0226 (12)0.0240 (13)0.0010 (10)0.0075 (10)−0.0005 (10)
C120.0335 (15)0.0278 (14)0.0261 (14)0.0001 (11)0.0110 (12)−0.0017 (11)
C130.0374 (16)0.0284 (15)0.0401 (18)0.0025 (12)0.0130 (13)−0.0074 (12)
C140.0343 (16)0.0218 (14)0.0486 (19)0.0028 (11)0.0123 (14)0.0042 (13)
C150.0464 (17)0.0309 (15)0.0353 (16)0.0004 (12)0.0179 (14)0.0079 (12)
C160.0396 (16)0.0296 (14)0.0260 (14)−0.0013 (12)0.0140 (12)−0.0016 (11)
C210.0308 (14)0.0213 (13)0.0196 (13)0.0007 (10)0.0092 (11)−0.0026 (10)
C220.0324 (14)0.0265 (13)0.0245 (14)−0.0024 (11)0.0083 (11)0.0003 (11)
C230.0305 (14)0.0307 (15)0.0334 (15)−0.0024 (11)0.0081 (12)−0.0041 (12)
C240.0369 (16)0.0379 (16)0.0258 (15)0.0073 (13)−0.0001 (12)−0.0039 (12)
C250.0533 (19)0.0341 (16)0.0253 (15)0.0074 (14)0.0079 (13)0.0046 (12)
C260.0436 (16)0.0287 (14)0.0242 (14)−0.0019 (12)0.0139 (12)0.0010 (11)
C310.0328 (14)0.0246 (13)0.0224 (13)−0.0014 (11)0.0125 (11)0.0026 (10)
C320.0508 (19)0.0384 (17)0.0418 (18)−0.0200 (14)0.0265 (15)−0.0142 (14)
C330.071 (2)0.0453 (19)0.051 (2)−0.0190 (17)0.0426 (19)−0.0208 (16)
C340.0452 (18)0.0382 (17)0.0482 (19)−0.0025 (14)0.0308 (15)−0.0008 (14)
C350.0261 (14)0.0415 (16)0.0332 (16)−0.0012 (12)0.0101 (12)0.0012 (13)
C360.0273 (14)0.0402 (16)0.0211 (14)0.0002 (11)0.0062 (11)−0.0015 (11)
C410.0207 (12)0.0237 (13)0.0279 (14)0.0004 (10)0.0111 (10)0.0016 (11)
C420.0325 (15)0.0263 (14)0.0331 (16)0.0024 (11)0.0136 (12)0.0036 (11)
C430.0344 (15)0.0205 (14)0.0523 (19)−0.0018 (11)0.0153 (14)−0.0029 (13)
C440.0286 (15)0.0364 (16)0.0409 (17)−0.0016 (12)0.0080 (13)−0.0150 (13)
C450.0352 (15)0.0358 (16)0.0281 (15)0.0008 (12)0.0098 (12)−0.0065 (12)
C460.0305 (14)0.0223 (13)0.0304 (15)0.0002 (10)0.0122 (12)−0.0014 (11)
N10.0240 (11)0.0265 (11)0.0232 (11)−0.0061 (9)0.0110 (9)−0.0069 (9)
N20.0212 (10)0.0203 (10)0.0256 (11)−0.0024 (8)0.0051 (9)0.0004 (9)
P10.0277 (3)0.0231 (3)0.0212 (3)−0.0023 (3)0.0112 (3)−0.0013 (3)
P20.0256 (3)0.0242 (3)0.0214 (3)−0.0009 (3)0.0069 (3)0.0011 (3)

Geometric parameters (Å, °)

C1—N11.465 (3)C24—C251.378 (4)
C1—C21.512 (4)C24—H240.9300
C1—H1A0.9700C25—C261.390 (4)
C1—H1B0.9700C25—H250.9300
C2—H2A0.9600C26—H260.9300
C2—H2B0.9600C31—C321.393 (4)
C2—H2C0.9600C31—C361.393 (4)
C3—N21.471 (3)C31—P21.846 (3)
C3—C41.510 (4)C32—C331.390 (4)
C3—H3A0.9700C32—H320.9300
C3—H3B0.9700C33—C341.375 (4)
C4—H4A0.9600C33—H330.9300
C4—H4B0.9600C34—C351.381 (4)
C4—H4C0.9600C34—H340.9300
C11—C121.396 (3)C35—C361.386 (4)
C11—C161.398 (4)C35—H350.9300
C11—P11.834 (3)C36—H360.9300
C12—C131.383 (4)C41—C461.395 (4)
C12—H120.9300C41—C421.405 (3)
C13—C141.380 (4)C41—P21.833 (3)
C13—H130.9300C42—C431.383 (4)
C14—C151.374 (4)C42—H420.9300
C14—H140.9300C43—C441.385 (4)
C15—C161.390 (4)C43—H430.9300
C15—H150.9300C44—C451.378 (4)
C16—H160.9300C44—H440.9300
C21—C221.396 (4)C45—C461.391 (4)
C21—C261.397 (4)C45—H450.9300
C21—P11.847 (3)C46—H460.9300
C22—C231.384 (4)N1—N21.426 (3)
C22—H220.9300N1—P11.692 (2)
C23—C241.381 (4)N2—P21.710 (2)
C23—H230.9300
N1—C1—C2114.7 (2)C24—C25—C26120.0 (3)
N1—C1—H1A108.6C24—C25—H25120.0
C2—C1—H1A108.6C26—C25—H25120.0
N1—C1—H1B108.6C25—C26—C21120.7 (3)
C2—C1—H1B108.6C25—C26—H26119.6
H1A—C1—H1B107.6C21—C26—H26119.6
C1—C2—H2A109.5C32—C31—C36117.5 (2)
C1—C2—H2B109.5C32—C31—P2117.4 (2)
H2A—C2—H2B109.5C36—C31—P2124.9 (2)
C1—C2—H2C109.5C33—C32—C31120.8 (3)
H2A—C2—H2C109.5C33—C32—H32119.6
H2B—C2—H2C109.5C31—C32—H32119.6
N2—C3—C4113.6 (2)C34—C33—C32120.9 (3)
N2—C3—H3A108.8C34—C33—H33119.5
C4—C3—H3A108.8C32—C33—H33119.5
N2—C3—H3B108.8C33—C34—C35119.1 (3)
C4—C3—H3B108.8C33—C34—H34120.5
H3A—C3—H3B107.7C35—C34—H34120.5
C3—C4—H4A109.5C34—C35—C36120.3 (3)
C3—C4—H4B109.5C34—C35—H35119.9
H4A—C4—H4B109.5C36—C35—H35119.9
C3—C4—H4C109.5C35—C36—C31121.4 (3)
H4A—C4—H4C109.5C35—C36—H36119.3
H4B—C4—H4C109.5C31—C36—H36119.3
C12—C11—C16117.6 (2)C46—C41—C42117.5 (2)
C12—C11—P1116.66 (19)C46—C41—P2124.53 (19)
C16—C11—P1125.7 (2)C42—C41—P2118.0 (2)
C13—C12—C11121.4 (3)C43—C42—C41121.2 (3)
C13—C12—H12119.3C43—C42—H42119.4
C11—C12—H12119.3C41—C42—H42119.4
C14—C13—C12120.2 (3)C42—C43—C44120.2 (3)
C14—C13—H13119.9C42—C43—H43119.9
C12—C13—H13119.9C44—C43—H43119.9
C15—C14—C13119.3 (3)C45—C44—C43119.6 (3)
C15—C14—H14120.3C45—C44—H44120.2
C13—C14—H14120.3C43—C44—H44120.2
C14—C15—C16121.0 (3)C44—C45—C46120.4 (3)
C14—C15—H15119.5C44—C45—H45119.8
C16—C15—H15119.5C46—C45—H45119.8
C15—C16—C11120.4 (3)C45—C46—C41121.0 (2)
C15—C16—H16119.8C45—C46—H46119.5
C11—C16—H16119.8C41—C46—H46119.5
C22—C21—C26118.2 (2)N2—N1—C1114.50 (19)
C22—C21—P1124.72 (19)N2—N1—P1118.43 (15)
C26—C21—P1117.0 (2)C1—N1—P1126.87 (16)
C23—C22—C21120.8 (2)N1—N2—C3114.66 (19)
C23—C22—H22119.6N1—N2—P2116.47 (15)
C21—C22—H22119.6C3—N2—P2121.99 (16)
C24—C23—C22120.1 (3)N1—P1—C11105.93 (11)
C24—C23—H23119.9N1—P1—C21105.29 (11)
C22—C23—H23119.9C11—P1—C2198.39 (11)
C25—C24—C23120.1 (3)N2—P2—C41102.11 (11)
C25—C24—H24120.0N2—P2—C31104.86 (11)
C23—C24—H24120.0C41—P2—C3199.40 (11)
C16—C11—C12—C13−1.9 (4)C2—C1—N1—N2−60.7 (3)
P1—C11—C12—C13178.3 (2)C2—C1—N1—P1114.0 (2)
C11—C12—C13—C140.4 (4)C1—N1—N2—C3−113.0 (2)
C12—C13—C14—C151.0 (4)P1—N1—N2—C371.8 (2)
C13—C14—C15—C16−1.0 (4)C1—N1—N2—P295.4 (2)
C14—C15—C16—C11−0.4 (4)P1—N1—N2—P2−79.8 (2)
C12—C11—C16—C151.8 (4)C4—C3—N2—N157.0 (3)
P1—C11—C16—C15−178.4 (2)C4—C3—N2—P2−153.17 (19)
C26—C21—C22—C231.0 (4)N2—N1—P1—C11−123.59 (17)
P1—C21—C22—C23177.6 (2)C1—N1—P1—C1161.9 (2)
C21—C22—C23—C24−1.7 (4)N2—N1—P1—C21132.80 (17)
C22—C23—C24—C251.2 (4)C1—N1—P1—C21−41.7 (2)
C23—C24—C25—C260.0 (4)C12—C11—P1—N1176.22 (19)
C24—C25—C26—C21−0.6 (4)C16—C11—P1—N1−3.6 (3)
C22—C21—C26—C250.1 (4)C12—C11—P1—C21−75.2 (2)
P1—C21—C26—C25−176.7 (2)C16—C11—P1—C21105.1 (2)
C36—C31—C32—C33−0.5 (4)C22—C21—P1—N185.1 (2)
P2—C31—C32—C33−177.0 (3)C26—C21—P1—N1−98.2 (2)
C31—C32—C33—C340.9 (5)C22—C21—P1—C11−24.0 (2)
C32—C33—C34—C35−0.3 (5)C26—C21—P1—C11152.6 (2)
C33—C34—C35—C36−0.9 (5)N1—N2—P2—C41−131.64 (17)
C34—C35—C36—C311.4 (4)C3—N2—P2—C4179.0 (2)
C32—C31—C36—C35−0.7 (4)N1—N2—P2—C31125.09 (17)
P2—C31—C36—C35175.6 (2)C3—N2—P2—C31−24.3 (2)
C46—C41—C42—C43−1.7 (4)C46—C41—P2—N20.8 (2)
P2—C41—C42—C43−179.7 (2)C42—C41—P2—N2178.72 (19)
C41—C42—C43—C440.2 (4)C46—C41—P2—C31108.3 (2)
C42—C43—C44—C451.1 (4)C42—C41—P2—C31−73.7 (2)
C43—C44—C45—C46−1.0 (4)C32—C31—P2—N2−78.5 (2)
C44—C45—C46—C41−0.5 (4)C36—C31—P2—N2105.2 (2)
C42—C41—C46—C451.8 (4)C32—C31—P2—C41176.2 (2)
P2—C41—C46—C45179.7 (2)C36—C31—P2—C41−0.1 (3)

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: WN2384).

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