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Acta Crystallogr Sect E Struct Rep Online. 2010 January 1; 66(Pt 1): o132.
Published online 2009 December 12. doi:  10.1107/S1600536809047412
PMCID: PMC2980158

Bis(2-naphthyl­meth­yl)diphenyl­silane

Abstract

The title compound, C34H28Si, was prepared as an inter­nal standard for diffusion-ordered NMR spectroscopy. The four ligands are arranged tetra­hedrally around the Si atom. The two naphthalene systems are nearly perpendicular, making an angle of 86.42 (4)° with one another. A naphthalene system and a phenyl ring are also nearly perpendicular, making an angle of 86.18 (6)° with one another. In the crystal, the mol­ecules pack in columns parallel to the a axis, and exhibit arene C—H(...)π(arene) inter­actions both within and between columns.

Related literature

For applications of the title compound related to NMR spectroscopy, see: Li et al. (2009 [triangle]). A search of the Cambridge Structural Database (Allen, 2002 [triangle]; CONQUEST; Bruno et al., 2002 [triangle]) yielded no comparable structures.

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Object name is e-66-0o132-scheme1.jpg

Experimental

Crystal data

  • C34H28Si
  • M r = 464.65
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-0o132-efi1.jpg
  • a = 9.4884 (14) Å
  • b = 11.0673 (13) Å
  • c = 13.3450 (15) Å
  • α = 75.820 (9)°
  • β = 83.767 (11)°
  • γ = 70.575 (11)°
  • V = 1280.8 (3) Å3
  • Z = 2
  • Cu Kα radiation
  • μ = 0.94 mm−1
  • T = 295 K
  • 0.36 × 0.20 × 0.05 mm

Data collection

  • Enraf–Nonius CAD-4 diffractometer
  • Absorption correction: analytical (Alcock, 1970 [triangle]) T min = 0.814, T max = 0.954
  • 9101 measured reflections
  • 4618 independent reflections
  • 3060 reflections with I > 2σ(I)
  • R int = 0.045
  • 3 standard reflections every 165 reflections intensity decay: 1%

Refinement

  • R[F 2 > 2σ(F 2)] = 0.037
  • wR(F 2) = 0.102
  • S = 1.01
  • 4618 reflections
  • 333 parameters
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.17 e Å−3
  • Δρmin = −0.20 e Å−3

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994 [triangle]); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995 [triangle]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 [triangle]) and Mercury (Macrae et al., 2006 [triangle]); software used to prepare material for publication: WinGX (Farrugia, 1999 [triangle]).

Table 1
Arene C—H(...)π (arene) packing interactions (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809047412/fl2263sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809047412/fl2263Isup2.hkl

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

Acknowledgments

This work was supported in part by funds provided by the University of North Carolina at Charlotte. Support for REU participant TBM was provided by the National Science Foundation, award number CHE-0851797.

supplementary crystallographic information

Comment

The title compound was prepared as an internal standard for diffusion-ordered NMR spectroscopy. A recent paper on this subject (Li et al., 2009) suggests an internal standard method for correlating diffusion coefficients with formula weights. The title compound was chosen because its shape both approximates that of a spheroid and is similar to that of the species being studied. In addition, it neither reacts with the species under study nor gives interfering NMR signals.

The ligands are arranged tetrahedrally around the silicon atom. The two naphthalene rings of the title compound are nearly perpendicular, making an angle of 86.42 (4)° with one another. A naphthalene ring and a phenyl ring are also nearly perpendicular, making an angle of 86.18 (6)° with one another. The angle between the phenyl rings is 74.35 (7)°. The molecules pack in columns parallel to the a axis and exhibit arene C—H··· arene π interactions both within and between columns. These interactions between a phenyl of one molecule and a proximal aromatic ring of a naphthyl on a molecule in an adjacent column are 2.879 (3) Å in length (Figure 2). The interactions between two phenyls of two adjacent molecules in the same column are 2.659 (2) Å in length (Figure 2). The interactions between a phenyl of one molecule and a distal aromatic ring of a naphthyl on an adjacent molecule in the same column are 2.757 (2) Å in length (Figure 3).

A search of the Cambridge Structural Database [Version 5.30 (Allen, 2002); CONQUEST (Bruno et al., 2002)] yielded no comparable structures. The search fragment used consisted of two naphthalene rings coordinated to Si, both with and without the methylene bridges.

Experimental

A dry, 250 ml Schlenk flask, equipped with a magnetic stir bar, was charged with 2-methylnaphthalene (I) (4.26 g, 300 mmol) and potassium tert-butoxide (3.92 g, 350 mmol). The Schlenk flask was purged with nitrogen. Freshly distilled THF (100 ml) was added and the reaction was cooled to -78 °C. n-BuLi (15.2 ml, 2.3 M) was then added dropwise. The Schlenk flask was then capped and kept at -40 °C overnight. The solution was again cooled to -78 °C and 2.09 ml (2.52 g, 100 mmol) of dichlorodiphenylsilane was added dropwise. The reaction mixture was allowed to warm to room temperature and stirred for 2 h. The mixture was then quenched with deionized water and extracted three times with hexanes. The combined organic layers were dried with magnesium sulfate, filtered, and evaporated. Bulb-to-bulb distillation gave a tan solid, which was recrystallized from hexanes to yield colorless crystals of the title compound (II) (2.56 g, 55% recovery).

mp 98 - 100 °C; 1H NMR (DMSO-d6, 300 MHz): 2.86(s), 6.97 (d), 7.32 (m), 7.41(m), 7.58 (m), 7.75 (d) p.p.m.. 13C NMR (DMSO-d6, 300 MHz): 21.92, 125.83, 126.27, 126.73, 127.10, 127.36, 127.71, 128.19, 129.59, 130.65, 133.06, 134.18, 135.14, 136.11 p.p.m.. GC/MS (70ev) m/z: 464.3, 323.2, 245.1, 215.1,193.1, 167.1, 141.1, 105.0.

Refinement

The four H atoms bonded to the methylene carbons were located in a difference map and refined. All other H atoms were constrained using a riding model; the C—H bond lengths were fixed at 0.93 Å with Uiso(H) = 1.2 Ueq(C).

Figures

Fig. 1.
View of title compound (50% probability displacement ellipsoids)
Fig. 2.
Diagram showing how molecules of the title compound form columns parallel to the a axis. Naphthyl-phenyl C—H···π interactions between columns and phenyl-phenyl C—H···π interactions ...
Fig. 3.
Diagram showing naphthyl-phenyl C—H···π interactions within columns
Fig. 4.
Synthesis scheme

Crystal data

C34H28SiZ = 2
Mr = 464.65F(000) = 492
Triclinic, P1Dx = 1.205 Mg m3
Hall symbol: -P 1Cu Kα radiation, λ = 1.54184 Å
a = 9.4884 (14) ÅCell parameters from 25 reflections
b = 11.0673 (13) Åθ = 9.7–40.3°
c = 13.3450 (15) ŵ = 0.94 mm1
α = 75.820 (9)°T = 295 K
β = 83.767 (11)°Prism, colorless
γ = 70.575 (11)°0.36 × 0.20 × 0.05 mm
V = 1280.8 (3) Å3

Data collection

Enraf–Nonius CAD-4 diffractometerRint = 0.045
Non–profiled ω/2θ scansθmax = 67.4°, θmin = 3.4°
Absorption correction: analytical (see. N.W. Alcock (1970))h = −11→11
Tmin = 0.814, Tmax = 0.954k = −13→13
9101 measured reflectionsl = −15→15
4618 independent reflections3 standard reflections every 165 reflections
3060 reflections with I > 2σ(I) intensity decay: 1%

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.037H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.102w = 1/[σ2(Fo2) + (0.0422P)2 + 0.1595P] where P = (Fo2 + 2Fc2)/3
S = 1.00(Δ/σ)max = 0.001
4618 reflectionsΔρmax = 0.17 e Å3
333 parametersΔρmin = −0.20 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0037 (4)

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)

xyzUiso*/Ueq
H24B0.231 (2)0.353 (2)0.7647 (17)0.069 (7)*
H13A0.348 (2)0.458 (2)0.5907 (16)0.067 (7)*
H24A0.117 (3)0.479 (2)0.7954 (16)0.063 (6)*
H13B0.422 (3)0.572 (2)0.5734 (18)0.085 (8)*
Si0.34325 (6)0.51722 (5)0.74770 (4)0.04382 (15)
C10.5414 (2)0.42670 (17)0.78451 (14)0.0431 (4)
C70.2828 (2)0.67956 (18)0.78528 (13)0.0429 (4)
C140.1897 (2)0.64223 (19)0.55711 (14)0.0484 (5)
C250.2299 (2)0.34952 (18)0.91925 (15)0.0468 (5)
C120.3864 (2)0.73768 (19)0.80112 (15)0.0507 (5)
H120.48800.69360.79450.061*
C22−0.0752 (2)0.7066 (2)0.52307 (14)0.0500 (5)
C270.2921 (2)0.15022 (19)1.05667 (16)0.0489 (5)
C320.2569 (2)0.22750 (19)1.13133 (15)0.0481 (5)
C340.1945 (2)0.42439 (19)0.99582 (16)0.0554 (5)
H340.16100.51560.97600.067*
C260.2781 (2)0.21659 (19)0.94994 (16)0.0520 (5)
H260.30300.16680.89990.062*
C230.0584 (2)0.6132 (2)0.56567 (15)0.0511 (5)
H230.05740.52960.60050.061*
C240.2150 (3)0.4184 (2)0.80615 (17)0.0561 (5)
C60.6578 (2)0.3999 (2)0.71170 (16)0.0559 (5)
H60.63590.42490.64190.067*
C330.2086 (2)0.3654 (2)1.09779 (16)0.0556 (5)
H330.18590.41711.14650.067*
C80.1324 (2)0.75053 (19)0.79637 (16)0.0533 (5)
H80.06020.71540.78600.064*
C20.5820 (2)0.38502 (19)0.88809 (15)0.0534 (5)
H20.50810.40050.93950.064*
C17−0.0733 (2)0.8326 (2)0.46839 (15)0.0538 (5)
C110.3415 (2)0.8586 (2)0.82632 (17)0.0610 (6)
H110.41280.89510.83590.073*
C130.3323 (2)0.5450 (2)0.60306 (15)0.0533 (5)
C50.8042 (2)0.3374 (2)0.73991 (18)0.0667 (6)
H50.87930.32200.68920.080*
C90.0876 (2)0.8709 (2)0.82220 (17)0.0610 (6)
H9−0.01380.91550.82940.073*
C310.2693 (2)0.1627 (2)1.23757 (16)0.0594 (5)
H310.24640.21191.28800.071*
C100.1923 (2)0.9257 (2)0.83749 (17)0.0608 (6)
H100.16231.00700.85510.073*
C30.7281 (2)0.3218 (2)0.91611 (17)0.0593 (5)
H30.75130.29510.98570.071*
C40.8400 (2)0.2979 (2)0.84222 (18)0.0630 (6)
H40.93890.25540.86130.076*
C150.1884 (2)0.7688 (2)0.50217 (16)0.0590 (5)
H150.27610.79050.49550.071*
C21−0.2121 (3)0.6793 (2)0.5334 (2)0.0698 (6)
H21−0.21620.59700.56900.084*
C160.0625 (3)0.8597 (2)0.45870 (17)0.0627 (6)
H160.06620.94160.42170.075*
C280.3387 (2)0.0136 (2)1.08931 (19)0.0642 (6)
H280.3629−0.03771.04030.077*
C300.3144 (2)0.0290 (2)1.26605 (18)0.0678 (7)
H300.3221−0.01271.33570.081*
C290.3492 (3)−0.0456 (2)1.1907 (2)0.0709 (7)
H290.3799−0.13681.21070.085*
C18−0.2061 (3)0.9261 (2)0.42547 (18)0.0712 (6)
H18−0.20511.00900.38910.085*
C20−0.3378 (3)0.7729 (3)0.4914 (2)0.0857 (8)
H20−0.42740.75410.49930.103*
C19−0.3347 (3)0.8966 (3)0.4365 (2)0.0856 (8)
H19−0.42140.95900.40750.103*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Si0.0394 (3)0.0496 (3)0.0420 (3)−0.0157 (2)−0.0023 (2)−0.0067 (2)
C10.0433 (11)0.0416 (10)0.0431 (10)−0.0136 (8)−0.0019 (8)−0.0067 (8)
C70.0369 (10)0.0512 (10)0.0399 (10)−0.0163 (8)−0.0019 (8)−0.0052 (8)
C140.0488 (12)0.0609 (12)0.0367 (10)−0.0181 (10)−0.0011 (8)−0.0121 (8)
C250.0392 (11)0.0510 (11)0.0520 (11)−0.0213 (9)0.0014 (9)−0.0061 (9)
C120.0329 (10)0.0570 (12)0.0618 (12)−0.0129 (9)0.0000 (9)−0.0150 (9)
C220.0469 (12)0.0643 (12)0.0448 (11)−0.0203 (10)−0.0008 (9)−0.0200 (9)
C270.0386 (11)0.0518 (11)0.0584 (12)−0.0198 (9)0.0030 (9)−0.0104 (9)
C320.0334 (10)0.0538 (11)0.0573 (12)−0.0175 (8)0.0023 (8)−0.0091 (9)
C340.0508 (13)0.0489 (11)0.0638 (13)−0.0159 (9)0.0040 (10)−0.0099 (10)
C260.0490 (12)0.0548 (12)0.0590 (12)−0.0244 (9)0.0057 (9)−0.0172 (10)
C230.0532 (12)0.0548 (11)0.0481 (11)−0.0210 (10)−0.0029 (9)−0.0106 (9)
C240.0560 (14)0.0611 (13)0.0546 (13)−0.0276 (12)−0.0042 (10)−0.0055 (10)
C60.0466 (12)0.0663 (13)0.0483 (11)−0.0115 (10)0.0003 (9)−0.0110 (10)
C330.0512 (13)0.0582 (12)0.0603 (13)−0.0190 (10)0.0083 (10)−0.0207 (10)
C80.0355 (11)0.0580 (12)0.0670 (13)−0.0161 (9)−0.0042 (9)−0.0121 (10)
C20.0482 (12)0.0630 (12)0.0472 (11)−0.0156 (10)−0.0017 (9)−0.0115 (9)
C170.0507 (12)0.0613 (12)0.0473 (11)−0.0143 (10)−0.0038 (9)−0.0122 (9)
C110.0490 (13)0.0616 (13)0.0800 (15)−0.0246 (11)−0.0027 (11)−0.0195 (11)
C130.0482 (13)0.0628 (13)0.0471 (11)−0.0156 (10)−0.0037 (9)−0.0104 (10)
C50.0463 (13)0.0776 (15)0.0668 (15)−0.0077 (11)0.0054 (11)−0.0188 (12)
C90.0388 (12)0.0584 (13)0.0793 (16)−0.0065 (10)−0.0044 (11)−0.0151 (11)
C310.0437 (12)0.0820 (15)0.0564 (13)−0.0271 (11)0.0035 (10)−0.0146 (11)
C100.0523 (13)0.0514 (12)0.0764 (15)−0.0097 (10)−0.0052 (11)−0.0179 (11)
C30.0554 (13)0.0637 (13)0.0557 (12)−0.0169 (11)−0.0148 (10)−0.0051 (10)
C40.0443 (12)0.0586 (13)0.0793 (16)−0.0061 (10)−0.0128 (11)−0.0126 (11)
C150.0510 (13)0.0677 (14)0.0594 (13)−0.0259 (11)0.0018 (10)−0.0078 (11)
C210.0592 (15)0.0777 (16)0.0843 (17)−0.0321 (13)−0.0011 (13)−0.0252 (13)
C160.0600 (15)0.0583 (13)0.0653 (14)−0.0217 (11)−0.0031 (11)−0.0012 (10)
C280.0576 (14)0.0535 (12)0.0812 (16)−0.0199 (11)0.0014 (12)−0.0130 (11)
C300.0491 (13)0.0839 (17)0.0618 (14)−0.0294 (12)−0.0085 (11)0.0142 (13)
C290.0606 (15)0.0563 (13)0.0880 (18)−0.0216 (11)−0.0068 (13)0.0045 (13)
C180.0607 (16)0.0724 (15)0.0703 (15)−0.0084 (12)−0.0149 (12)−0.0095 (12)
C200.0470 (15)0.106 (2)0.116 (2)−0.0242 (14)−0.0099 (14)−0.0429 (18)
C190.0596 (17)0.0880 (19)0.104 (2)−0.0052 (14)−0.0254 (15)−0.0265 (16)

Geometric parameters (Å, °)

Si—C11.868 (2)C8—H80.9300
Si—C71.8714 (19)C2—C31.375 (3)
Si—C241.883 (2)C2—H20.9300
Si—C131.887 (2)C17—C161.402 (3)
C1—C61.393 (3)C17—C181.409 (3)
C1—C21.399 (3)C11—C101.373 (3)
C7—C81.393 (3)C11—H110.9300
C7—C121.399 (3)C13—H13A0.98 (2)
C14—C231.373 (3)C13—H13B1.00 (3)
C14—C151.409 (3)C5—C41.371 (3)
C14—C131.501 (3)C5—H50.9300
C25—C261.356 (3)C9—C101.379 (3)
C25—C341.414 (3)C9—H90.9300
C25—C241.513 (3)C31—C301.362 (3)
C12—C111.376 (3)C31—H310.9300
C12—H120.9300C10—H100.9300
C22—C171.412 (3)C3—C41.372 (3)
C22—C231.413 (3)C3—H30.9300
C22—C211.415 (3)C4—H40.9300
C27—C281.395 (3)C15—C161.357 (3)
C27—C321.411 (3)C15—H150.9300
C27—C261.432 (3)C21—C201.360 (3)
C32—C331.409 (3)C21—H210.9300
C32—C311.421 (3)C16—H160.9300
C34—C331.357 (3)C28—C291.349 (3)
C34—H340.9300C28—H280.9300
C26—H260.9300C30—C291.398 (3)
C23—H230.9300C30—H300.9300
C24—H24B0.98 (2)C29—H290.9300
C24—H24A0.95 (2)C18—C191.348 (3)
C6—C51.378 (3)C18—H180.9300
C6—H60.9300C20—C191.393 (4)
C33—H330.9300C20—H200.9300
C8—C91.375 (3)C19—H190.9300
C1—Si—C7109.26 (8)C16—C17—C18122.4 (2)
C1—Si—C24111.99 (10)C16—C17—C22118.1 (2)
C7—Si—C24111.63 (10)C18—C17—C22119.5 (2)
C1—Si—C13108.42 (9)C10—C11—C12120.6 (2)
C7—Si—C13109.40 (9)C10—C11—H11119.7
C24—Si—C13106.01 (11)C12—C11—H11119.7
C6—C1—C2115.99 (18)C14—C13—Si115.41 (14)
C6—C1—Si122.70 (15)C14—C13—H13A111.2 (13)
C2—C1—Si121.28 (14)Si—C13—H13A104.7 (12)
C8—C7—C12116.43 (17)C14—C13—H13B111.9 (14)
C8—C7—Si121.88 (15)Si—C13—H13B105.3 (14)
C12—C7—Si121.67 (14)H13A—C13—H13B107.8 (18)
C23—C14—C15117.76 (19)C4—C5—C6120.4 (2)
C23—C14—C13122.66 (19)C4—C5—H5119.8
C15—C14—C13119.57 (19)C6—C5—H5119.8
C26—C25—C34118.44 (18)C8—C9—C10120.23 (19)
C26—C25—C24121.77 (19)C8—C9—H9119.9
C34—C25—C24119.78 (18)C10—C9—H9119.9
C11—C12—C7121.53 (18)C30—C31—C32120.4 (2)
C11—C12—H12119.2C30—C31—H31119.8
C7—C12—H12119.2C32—C31—H31119.8
C17—C22—C23119.21 (19)C11—C10—C9119.1 (2)
C17—C22—C21118.3 (2)C11—C10—H10120.4
C23—C22—C21122.5 (2)C9—C10—H10120.4
C28—C27—C32119.16 (19)C4—C3—C2120.5 (2)
C28—C27—C26122.86 (19)C4—C3—H3119.7
C32—C27—C26117.98 (17)C2—C3—H3119.7
C33—C32—C27118.82 (18)C5—C4—C3119.1 (2)
C33—C32—C31122.68 (19)C5—C4—H4120.4
C27—C32—C31118.49 (18)C3—C4—H4120.4
C33—C34—C25121.15 (18)C16—C15—C14121.7 (2)
C33—C34—H34119.4C16—C15—H15119.2
C25—C34—H34119.4C14—C15—H15119.2
C25—C26—C27122.31 (18)C20—C21—C22120.2 (2)
C25—C26—H26118.8C20—C21—H21119.9
C27—C26—H26118.8C22—C21—H21119.9
C14—C23—C22121.84 (19)C15—C16—C17121.3 (2)
C14—C23—H23119.1C15—C16—H16119.3
C22—C23—H23119.1C17—C16—H16119.3
C25—C24—Si118.49 (15)C29—C28—C27121.2 (2)
C25—C24—H24B108.9 (13)C29—C28—H28119.4
Si—C24—H24B106.1 (13)C27—C28—H28119.4
C25—C24—H24A109.2 (13)C31—C30—C29120.1 (2)
Si—C24—H24A104.8 (13)C31—C30—H30119.9
H24B—C24—H24A109.1 (18)C29—C30—H30119.9
C5—C6—C1122.0 (2)C28—C29—C30120.6 (2)
C5—C6—H6119.0C28—C29—H29119.7
C1—C6—H6119.0C30—C29—H29119.7
C34—C33—C32121.29 (19)C19—C18—C17120.7 (2)
C34—C33—H33119.4C19—C18—H18119.6
C32—C33—H33119.4C17—C18—H18119.6
C9—C8—C7122.04 (19)C21—C20—C19121.1 (2)
C9—C8—H8119.0C21—C20—H20119.4
C7—C8—H8119.0C19—C20—H20119.4
C3—C2—C1121.88 (19)C18—C19—C20120.2 (3)
C3—C2—H2119.1C18—C19—H19119.9
C1—C2—H2119.1C20—C19—H19119.9

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C3—H3···Cg1i0.932.663.569 (2)166
C5—H5···Cg2ii0.932.883.664 (2)143
C9—H9···Cg3iii0.932.763.577 (2)148

Symmetry codes: (i) −x+1, −y+1, −z+2; (ii) −x+1, −y+1, −z+1; (iii) −x, −y+1, −z+2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: FL2263).

References

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