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Acta Crystallogr Sect E Struct Rep Online. 2010 January 1; 66(Pt 1): o42–o43.
Published online 2009 December 4. doi:  10.1107/S1600536809050867
PMCID: PMC2980231

N,N′-Dineopentyl­naphthalene-1,8-diamine

Abstract

In the title compound, C20H30N2, all bond distances and angles fall within the usual ranges but the C(ipso)—N distances [1.391 (5) and 1.398 (4) Å] are slightly shorter than the corresponding typical average distance of 1.42 (3) Å. The N atoms may be described as pyramidal sp 3-hybridized with an N—H(...)H—N separation of 2.07 (2) Å. This is necessitated because the two C(bridgehead)—C(ipso)—N—C torsion angles [170.6 (4) and 172.6 (3)°] would require the amine H atoms to be in prohibitively close proximity if the N atoms were assumed to be sp 2-hybridized.

Related literature

For the use of 1,8-bis­(diamido)naphthalene (DAN) ligands in the preparation of thermally stable N-heterocyclic carbenes, germylenes and stannylenes, see: Avent et al. (2004 [triangle]); Bazinet et al. (2001a [triangle],b [triangle], 2003 [triangle], 2007 [triangle]). For our studies on N-heterocyclic silylenes, see: Hill et al. (2005 [triangle]); Li et al. (2006 [triangle]); Naka et al. (2004 [triangle]). For DAN ligands in transition metal coordination chemistry, see: Lavoie et al. (2007 [triangle]); Bazinet et al. (2001b [triangle]). Their titanium and zirconium complexes have been found to be effective catalysts for olefin polymerization, see: Lee et al. (2001 [triangle]). For a description of the Cambridge Structural Database, see: Allen (2002 [triangle]). For geometrical analysis, see: Bruno et al. (2002 [triangle]). For the preparation of the title compound, see: Daniele et al. (2001 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-00o42-scheme1.jpg

Experimental

Crystal data

  • C20H30N2
  • M r = 298.46
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-66-00o42-efi1.jpg
  • a = 6.0425 (14) Å
  • b = 16.196 (3) Å
  • c = 18.861 (4) Å
  • V = 1845.8 (7) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.06 mm−1
  • T = 300 K
  • 0.70 × 0.30 × 0.20 mm

Data collection

  • Bruker SMART X2S diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2009 [triangle]) T min = 0.958, T max = 0.988
  • 12752 measured reflections
  • 2042 independent reflections
  • 1203 reflections with I > 2σ(I)
  • R int = 0.090

Refinement

  • R[F 2 > 2σ(F 2)] = 0.053
  • wR(F 2) = 0.140
  • S = 0.93
  • 2042 reflections
  • 213 parameters
  • 6 restraints
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.12 e Å−3
  • Δρmin = −0.13 e Å−3

Data collection: GIS (Bruker, 2009 [triangle]); cell refinement: SAINT (Bruker, 2009 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXTL and OLEX2 (Dolomanov et al., 2009 [triangle]); molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL, publCIF (Westrip, 2009 [triangle]) and modiCIFer (Guzei, 2007 [triangle]).

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809050867/zs2021sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809050867/zs2021Isup2.hkl

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

Acknowledgments

We gratefully acknowledge Bruker sponsorship of this publication.

supplementary crystallographic information

Comment

1,8-Bis(diamido)naphthalene (DAN) ligands have recently been employed in the preparation of thermally stable N-heterocyclic carbenes, germylenes, and stannylenes (Avent et al., 2004; Bazinet et al., 2007; Bazinet et al., 2003; Bazinet et al., 2001a). As a continuation of our study of N-heterocyclic silylenes (Hill et al., 2005; Li et al., 2006; Naka et al., 2004), we sought to prepare the corresponding silicon compound. The title compound, C20H30N2 (I), was selected as a scaffold on account of the potentially greater steric protection afforded the reactive silicon(II) atom by the neopentyl group compared to the more common isopropyl analog. Our results in this area will be presented elsewhere.

DAN ligands have also been examined in the realm of transition metal coordination chemistry (e.g. Lavoie et al., 2007, Bazinet et al., 2001b). Their titanium and zirconium complexes have been found to be effective catalysts for olefin polymerization (Lee et al., 2001).

In the structure of the title compound (Fig. 1), all bond distances and angles fall in the usual ranges (Bruno et al., 2002). The C(ipso)-N distances [1.391 (5) and 1.398 (4) Å] are slightly shorter than the corresponding distance of 1.42 (3) Å, obtained by averaging 228 distances in 62 related compounds reported to the Cambridge Structural Database (CSD) (Allen, 2002). However, the difference is not statistically significant. An important feature of the structure is the location of the amine H atoms. Their positions are dependent on intermolecular hydrogen bonding (absent in our case), torsion angle [var phi] [ = C(bridgehead)-C(ipso)-N—C], and hybridization of the N atoms. The [var phi] angles in (I) [170.6 (4) and 172.6 (3)°], would require the amine H atoms to be in prohibitively close proximity if the N atoms are assumed to be sp2-hybridized. To avoid the steric conflict the N atoms are described as pyramidal sp3-hybridized with the N1—H1···H2—N2 separation of 2.07 (2) Å. In several related structures of DAN-derivatives reported to the CSD this problem is absent as the relative location of the N-substituents allows for intramolecular N—H···N hydrogen bonding. This is illustrated with dissimilar pairs of the [var phi] angles: 84.5 and -114.3° in HEYHEY, 92.0 and 107.8° in NAKKAL, 107.0 and 95.6° in NAKKEP, 92.9 and -178.1° in NUPJEN, 67.9 and 167.2° in OHOKAX, -119.1 and 158.0° in KOCTEC.

Experimental

The title compound was obtained by treatment of 1,8-diaminonaphthalene with 2,2-dimethylpropanoyl chloride followed by LiAlH4 reduction and aqueous work-up according to the procedure of Daniele et al. (2001). 1H– and 13C{1H}-NMR data were in agreement with literature values. Needle-like crystals suitable for X-ray diffraction studies were obtained from a solution of the title compound stored at -20 °C in THF for several weeks.

Refinement

All non-amine H-atoms were placed in idealized locations and refined as riding with appropriate thermal displacement coefficients Uiso(H) = 1.2 or 1.5 times Ueq(bearing atom). The amine H atoms were refined with the N—H distances restrained to 0.880 (1) Å and unconstrained thermal displacement coefficient. The refinement was performed with an 'anti-bumping' restraint. The Friedel pairs were merged.

Figures

Fig. 1.
The molecular structure of (I) with the thermal ellipsoids shown at 30% probability level.

Crystal data

C20H30N2F(000) = 656
Mr = 298.46Dx = 1.074 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 1989 reflections
a = 6.0425 (14) Åθ = 2.5–20.6°
b = 16.196 (3) ŵ = 0.06 mm1
c = 18.861 (4) ÅT = 300 K
V = 1845.8 (7) Å3Needle, yellow
Z = 40.70 × 0.30 × 0.20 mm

Data collection

Bruker SMART X2S diffractometer2042 independent reflections
Radiation source: micro-focus sealed tube1203 reflections with I > 2σ(I)
doubly curved silicon crystalRint = 0.090
ω scansθmax = 25.7°, θmin = 2.5°
Absorption correction: multi-scan (SADABS; Bruker, 2009)h = −7→7
Tmin = 0.958, Tmax = 0.988k = −19→15
12752 measured reflectionsl = −22→22

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)] = 0.053Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.140H atoms treated by a mixture of independent and constrained refinement
S = 0.93w = 1/[σ2(Fo2) + (0.079P)2] where P = (Fo2 + 2Fc2)/3
2042 reflections(Δ/σ)max < 0.001
213 parametersΔρmax = 0.12 e Å3
6 restraintsΔρmin = −0.13 e Å3

Special details

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)

xyzUiso*/Ueq
N10.3691 (7)0.6434 (2)0.30061 (17)0.0693 (11)
H10.309 (10)0.5953 (17)0.299 (2)0.16 (3)*
N20.2799 (6)0.55146 (19)0.41609 (17)0.0513 (8)
H20.396 (2)0.578 (2)0.404 (2)0.13 (2)*
C10.7600 (7)0.5450 (3)0.2652 (2)0.0726 (12)
H1C0.86050.58660.28180.109*
H1A0.84240.49970.24560.109*
H1B0.67140.52560.30400.109*
C20.7503 (10)0.6090 (3)0.1446 (2)0.1015 (18)
H2C0.85660.64930.15990.152*
H2B0.65620.63280.10910.152*
H2A0.82620.56210.12520.152*
C30.4470 (9)0.5158 (3)0.1828 (2)0.0908 (16)
H3A0.52740.46990.16330.136*
H3C0.35210.53870.14710.136*
H3B0.35920.49720.22210.136*
C40.6097 (7)0.5816 (2)0.20806 (19)0.0543 (10)
C50.4883 (9)0.6577 (3)0.2348 (2)0.0725 (13)
H5B0.59460.70180.24210.087*
H5A0.38440.67580.19880.087*
C60.2063 (6)0.6975 (2)0.32437 (18)0.0467 (10)
C70.1708 (8)0.7721 (2)0.2898 (2)0.0649 (12)
H70.26580.78810.25350.078*
C8−0.0050 (9)0.8235 (3)0.3087 (2)0.0762 (14)
H8−0.02520.87300.28460.091*
C9−0.1462 (8)0.8027 (2)0.3611 (2)0.0677 (12)
H9−0.26470.83710.37190.081*
C10−0.1146 (6)0.7286 (2)0.39979 (19)0.0484 (10)
C11−0.2626 (7)0.7085 (3)0.4547 (2)0.0574 (11)
H11−0.38170.74320.46430.069*
C12−0.2334 (7)0.6394 (2)0.4938 (2)0.0594 (11)
H12−0.33330.62640.52960.071*
C13−0.0538 (6)0.5874 (2)0.48056 (19)0.0507 (10)
H13−0.03620.54030.50830.061*
C140.0986 (6)0.60337 (19)0.42771 (17)0.0389 (8)
C150.0688 (6)0.67558 (19)0.38365 (17)0.0394 (8)
C160.3391 (6)0.4827 (2)0.46264 (18)0.0519 (10)
H16B0.27120.49200.50860.062*
H16A0.49820.48330.46950.062*
C170.2717 (6)0.3962 (2)0.43668 (18)0.0463 (9)
C180.3875 (8)0.3775 (3)0.3663 (2)0.0758 (13)
H18B0.33230.41390.33030.114*
H18A0.35880.32130.35290.114*
H18C0.54400.38550.37160.114*
C190.3484 (8)0.3340 (2)0.4927 (2)0.0747 (14)
H19A0.30800.27930.47810.112*
H19C0.27910.34640.53720.112*
H19B0.50620.33730.49780.112*
C200.0236 (7)0.3885 (2)0.4256 (2)0.0684 (12)
H20C−0.05100.39550.47010.103*
H20A−0.00990.33500.40660.103*
H20B−0.02520.43030.39300.103*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
N10.082 (3)0.059 (2)0.067 (2)0.013 (2)0.035 (2)0.0214 (17)
N20.049 (2)0.0449 (19)0.060 (2)0.0077 (17)0.0144 (18)0.0112 (15)
C10.057 (3)0.087 (3)0.074 (3)−0.001 (3)−0.001 (3)−0.017 (2)
C20.102 (4)0.118 (4)0.084 (3)0.004 (4)0.043 (4)0.008 (3)
C30.093 (4)0.105 (4)0.074 (3)−0.028 (3)−0.018 (3)−0.010 (3)
C40.053 (2)0.064 (3)0.046 (2)−0.007 (2)0.009 (2)−0.0063 (18)
C50.081 (3)0.074 (3)0.062 (3)−0.001 (3)0.020 (3)0.011 (2)
C60.051 (2)0.041 (2)0.048 (2)0.0028 (19)−0.0014 (19)0.0013 (17)
C70.076 (3)0.053 (3)0.066 (3)−0.001 (2)0.006 (2)0.012 (2)
C80.098 (4)0.052 (3)0.079 (3)0.018 (3)−0.006 (3)0.016 (2)
C90.073 (3)0.049 (3)0.081 (3)0.018 (2)−0.014 (3)−0.005 (2)
C100.048 (2)0.041 (2)0.056 (2)0.0026 (19)−0.011 (2)−0.0122 (17)
C110.042 (2)0.061 (3)0.070 (3)0.009 (2)0.004 (2)−0.021 (2)
C120.055 (3)0.056 (3)0.067 (3)−0.006 (2)0.020 (2)−0.017 (2)
C130.062 (3)0.041 (2)0.049 (2)−0.001 (2)0.009 (2)0.0002 (17)
C140.046 (2)0.0346 (19)0.0361 (18)−0.0018 (17)0.0020 (18)−0.0066 (15)
C150.043 (2)0.0343 (18)0.0413 (19)−0.0026 (17)−0.0055 (18)−0.0056 (15)
C160.048 (2)0.047 (2)0.061 (2)−0.0022 (19)−0.001 (2)0.0096 (18)
C170.043 (2)0.043 (2)0.053 (2)−0.0013 (18)−0.0042 (19)0.0048 (17)
C180.079 (3)0.065 (3)0.083 (3)0.000 (3)0.013 (3)−0.005 (2)
C190.071 (3)0.056 (3)0.097 (3)0.002 (2)−0.019 (3)0.026 (2)
C200.054 (3)0.060 (3)0.091 (3)−0.004 (2)−0.011 (2)0.004 (2)

Geometric parameters (Å, °)

N1—C61.391 (5)C9—C101.418 (5)
N1—C51.453 (5)C9—H90.9300
N1—H10.86 (3)C10—C111.407 (5)
N2—C141.398 (4)C10—C151.434 (5)
N2—C161.463 (4)C11—C121.352 (5)
N2—H20.86 (3)C11—H110.9300
C1—C41.528 (5)C12—C131.396 (5)
C1—H1C0.9600C12—H120.9300
C1—H1A0.9600C13—C141.382 (5)
C1—H1B0.9600C13—H130.9300
C2—C41.533 (5)C14—C151.446 (4)
C2—H2C0.9600C16—C171.537 (5)
C2—H2B0.9600C16—H16B0.9700
C2—H2A0.9600C16—H16A0.9700
C3—C41.526 (6)C17—C201.519 (5)
C3—H3A0.9600C17—C181.531 (5)
C3—H3C0.9600C17—C191.532 (5)
C3—H3B0.9600C18—H18B0.9600
C4—C51.521 (6)C18—H18A0.9600
C5—H5B0.9700C18—H18C0.9600
C5—H5A0.9700C19—H19A0.9600
C6—C71.390 (5)C19—H19C0.9600
C6—C151.438 (5)C19—H19B0.9600
C7—C81.396 (6)C20—H20C0.9600
C7—H70.9300C20—H20A0.9600
C8—C91.349 (6)C20—H20B0.9600
C8—H80.9300
C6—N1—C5121.7 (3)C11—C10—C9119.3 (4)
C6—N1—H1107 (5)C11—C10—C15120.6 (3)
C5—N1—H1108 (4)C9—C10—C15120.1 (4)
C14—N2—C16123.7 (3)C12—C11—C10120.6 (4)
C14—N2—H2112 (3)C12—C11—H11119.7
C16—N2—H2110.6 (14)C10—C11—H11119.7
C4—C1—H1C109.5C11—C12—C13120.3 (4)
C4—C1—H1A109.5C11—C12—H12119.9
H1C—C1—H1A109.5C13—C12—H12119.9
C4—C1—H1B109.5C14—C13—C12122.3 (3)
H1C—C1—H1B109.5C14—C13—H13118.9
H1A—C1—H1B109.5C12—C13—H13118.9
C4—C2—H2C109.5C13—C14—N2121.5 (3)
C4—C2—H2B109.5C13—C14—C15118.9 (3)
H2C—C2—H2B109.5N2—C14—C15119.6 (3)
C4—C2—H2A109.5C10—C15—C6117.6 (3)
H2C—C2—H2A109.5C10—C15—C14117.3 (3)
H2B—C2—H2A109.5C6—C15—C14125.1 (3)
C4—C3—H3A109.5N2—C16—C17115.9 (3)
C4—C3—H3C109.5N2—C16—H16B108.3
H3A—C3—H3C109.5C17—C16—H16B108.3
C4—C3—H3B109.5N2—C16—H16A108.3
H3A—C3—H3B109.5C17—C16—H16A108.3
H3C—C3—H3B109.5H16B—C16—H16A107.4
C5—C4—C3111.0 (4)C20—C17—C18108.4 (4)
C5—C4—C1111.5 (3)C20—C17—C19109.9 (3)
C3—C4—C1109.4 (4)C18—C17—C19109.2 (3)
C5—C4—C2107.0 (3)C20—C17—C16112.3 (3)
C3—C4—C2108.4 (3)C18—C17—C16109.6 (3)
C1—C4—C2109.5 (4)C19—C17—C16107.4 (3)
N1—C5—C4113.2 (3)C17—C18—H18B109.5
N1—C5—H5B108.9C17—C18—H18A109.5
C4—C5—H5B108.9H18B—C18—H18A109.5
N1—C5—H5A108.9C17—C18—H18C109.5
C4—C5—H5A108.9H18B—C18—H18C109.5
H5B—C5—H5A107.8H18A—C18—H18C109.5
C7—C6—N1120.3 (4)C17—C19—H19A109.5
C7—C6—C15119.4 (4)C17—C19—H19C109.5
N1—C6—C15120.3 (3)H19A—C19—H19C109.5
C6—C7—C8121.0 (4)C17—C19—H19B109.5
C6—C7—H7119.5H19A—C19—H19B109.5
C8—C7—H7119.5H19C—C19—H19B109.5
C9—C8—C7121.4 (4)C17—C20—H20C109.5
C9—C8—H8119.3C17—C20—H20A109.5
C7—C8—H8119.3H20C—C20—H20A109.5
C8—C9—C10120.2 (4)C17—C20—H20B109.5
C8—C9—H9119.9H20C—C20—H20B109.5
C10—C9—H9119.9H20A—C20—H20B109.5
C6—N1—C5—C4−163.9 (4)C16—N2—C14—C13−7.4 (5)
C3—C4—C5—N169.2 (5)C16—N2—C14—C15172.6 (3)
C1—C4—C5—N1−53.1 (5)C11—C10—C15—C6176.7 (3)
C2—C4—C5—N1−172.7 (4)C9—C10—C15—C6−4.4 (5)
C5—N1—C6—C7−7.5 (6)C11—C10—C15—C14−2.3 (5)
C5—N1—C6—C15170.6 (4)C9—C10—C15—C14176.6 (3)
N1—C6—C7—C8173.9 (4)C7—C6—C15—C106.2 (5)
C15—C6—C7—C8−4.2 (6)N1—C6—C15—C10−171.9 (3)
C6—C7—C8—C90.1 (7)C7—C6—C15—C14−174.8 (3)
C7—C8—C9—C101.8 (7)N1—C6—C15—C147.0 (5)
C8—C9—C10—C11179.4 (4)C13—C14—C15—C102.6 (4)
C8—C9—C10—C150.4 (6)N2—C14—C15—C10−177.4 (3)
C9—C10—C11—C12−178.2 (4)C13—C14—C15—C6−176.4 (3)
C15—C10—C11—C120.7 (5)N2—C14—C15—C63.7 (5)
C10—C11—C12—C130.8 (6)C14—N2—C16—C17101.3 (4)
C11—C12—C13—C14−0.5 (6)N2—C16—C17—C20−59.1 (4)
C12—C13—C14—N2178.7 (3)N2—C16—C17—C1861.5 (4)
C12—C13—C14—C15−1.2 (5)N2—C16—C17—C19−180.0 (3)

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: ZS2021).

References

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