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

Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 66| Part 7| July 2010| Pages o1846-o1847

2,3,6,7-Tetra­kis(bromo­meth­yl)naphthalene

aDepartment of Chemistry, University of Bremen, Leobener Strasse NW 2C, 28359 Bremen, Germany, and bInstitute of Inorganic and Analytical Chemistry, Technical University of Braunschweig, Postfach 3329, 38023 Braunschweig, Germany
*Correspondence e-mail: p.jones@tu-bs.de

(Received 3 June 2010; accepted 22 June 2010; online 26 June 2010)

The title compound, C14H12Br4, crystallizes with imposed inversion symmetry. In the crystal, the mol­ecules pack in layers parallel to (10[\overline{1}]). The layers involve two Br⋯Br and one H⋯Br contact. Between the layers, one contact each of types Br⋯Br, H⋯Br and Br⋯π is observed.

Related literature

For the use of 2,3,6,7-tetra­kis­(bromo­meth­yl)naphthalene in the preparation of cyclo­phanes, see: Otsubo et al. (1983[Otsubo, T., Ogura, F. & Misumi, S. (1983). Tetrahedron Lett. 24, 4851-4854.], 1989[Otsubo, T., Aso, Y., Ogura, F., Misumi, S., Kawamoto, A. & Tanaka, J. (1989). Bull. Chem. Soc. Jpn, 62, 164-170.]); Yano et al. (1999[Yano, K., Matsuda, S., Tani, K., Yamamoto, K. & Matsubara, H. (1999). Bull. Chem. Soc. Jpn, 72, 2111-2114.]); Skibiński et al. (2009[Skibiński, M., Gómez, R., Lork, E. & Azov, V. A. (2009). Tetrahedron, 65, 10348-10354.]). For its applications in the synthesis of hydrogen-bonded mol­ecular capsules, see: Valdes et al. (1995[Valdes, C., Spitz, U. P., Toledo, L. M., Kubik, S. W. & Rebek, J. Jr (1995). J. Am. Chem. Soc. 117, 12733-12745.]); Rivera et al. (2001[Rivera, J. M., Martin, T. & Rebek, J. Jr (2001). J. Am. Chem. Soc. 123, 5213-5220.]). For reviews on halogen–halogen contacts and `weak' hydrogen bonding, see: Desiraju & Steiner (1999[Desiraju, G. R. & Steiner, T. (1999). The Weak Hydrogen Bond in Structural Chemistry and Biology. Oxford University Press.]); Metrangolo & Resnati (2001[Metrangolo, P. & Resnati, G. (2001). Chem. Eur. J. 7, 2511-2519.]); Metrangolo et al. (2008[Metrangolo, P., Meyer, F., Pilati, T., Resnati, G. & Terraneo, G. (2008). Angew. Chem. Int. Ed. 47, 6114-6127.]); Rissanen (2008[Rissanen, K. (2008). CrystEngComm, 10, 1107-1113.]). For the X-ray structures of the full series of ten isomeric bis­(bromo­meth­yl)naphthalenes, see: Jones & Kuś (2010[Jones, P. G. & Kuś, P. (2010). Z. Naturforsch. Teil B, 65, 433-444.]). For the X-ray structures of two isomeric tetra­kis­(bromo­meth­yl)benz­ene derivatives, see: Jones & Kuś (2007[Jones, P. G. & Kuś, P. (2007). Z. Naturforsch. Teil B, 62, 725-731.]).

[Scheme 1]

Experimental

Crystal data
  • C14H12Br4

  • Mr = 499.88

  • Triclinic, [P \overline 1]

  • a = 6.6144 (2) Å

  • b = 7.1770 (2) Å

  • c = 8.7761 (3) Å

  • α = 84.744 (3)°

  • β = 78.251 (3)°

  • γ = 64.555 (3)°

  • V = 368.32 (2) Å3

  • Z = 1

  • Mo Kα radiation

  • μ = 10.91 mm−1

  • T = 100 K

  • 0.20 × 0.06 × 0.04 mm

Data collection
  • Oxford Diffraction Xcalibur Eos diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, England.]) Tmin = 0.356, Tmax = 1.000

  • 17701 measured reflections

  • 2122 independent reflections

  • 1716 reflections with I > 2σ(I)

  • Rint = 0.031

Refinement
  • R[F2 > 2σ(F2)] = 0.016

  • wR(F2) = 0.034

  • S = 0.92

  • 2122 reflections

  • 82 parameters

  • H-atom parameters constrained

  • Δρmax = 0.50 e Å−3

  • Δρmin = −0.49 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C6—H6A⋯Br2i 0.99 2.96 3.7967 (17) 143
C6—H6A⋯Br2ii 0.99 2.98 3.7359 (16) 134
C5—H5⋯Br1iii 0.95 3.11 3.9399 (16) 147
Symmetry codes: (i) x, y-1, z; (ii) -x, -y+1, -z+1; (iii) -x+1, -y+1, -z.

Table 2
Bromine–bromine and related contacts and angles (Å, °)

Cg is the centroid of the C1–C5,C1(−x, 1 − y, −z) ring.

System C—Br⋯Br—C or C—Br⋯Cg Br⋯Br or Br⋯Cg C—Br⋯Br (or C—Br⋯Cg), Br⋯Br—C Operator
C6—Br1⋯Br2—C7 3.8972 (3) 76.45 (5), 134.79 (5) 1-x, 1-y, 1-z
C7—Br2⋯Br2—C7 3.8873 (4) 134.93 (5) × 2 -x, 2-y, 1-z
C7—Br2⋯Br2—C7 3.8913 (4) 76.72 (5) × 2 1-x, 1-y, 1-z
C6—Br1⋯Cg 3.89 158 1+x, -1+y, z

Data collection: CrysAlis PRO (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; 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: XP (Siemens, 1994[Siemens (1994). XP. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

The title compound is a symmetric rigid molecule with four bromomethyl groups. The bromine atoms can be easily substituted by other nucleophiles, which offers the opportunity of employing the compound as a building block for construction of various functional architectures. The title compound was prepared to serve as a spacer between two tetrathiafulvalene (TTF) groups in TTF-containing molecular tweezers (Skibiński et al., 2009). It was first employed as an intermediate in the preparation of triple-layered [2.2]naphthalenophane (Otsubo et al., 1983), and several other triple-layered cyclophanes (Otsubo et al., 1983; Yano et al., 1999). It was also used as an intermediate in the synthesis of H-bonded molecular capsules (Valdes et al., 1995; Rivera et al., 2001).

The molecule of the title compound is shown in Fig. 1. It displays crystallographic inversion symmetry (operator #1 - x, 1 - y, 1 - z); for this reason, the crystallographic numbering does not correspond to the IUPAC numbering scheme. Bond lengths and angles may be considered normal; the bromine atoms are directed to opposite sides of the ring system, with C(2)—C(3)—C(6)—Br(1) 92.22 (16), C(3)—C(4)—C(7)—Br2 - 79.86 (17)°, which leads to a +/-/-/+ pattern of Br atoms about the ring plane for the IUPAC-numbered C2,3,6,7; this contrasts with the -/-/+/+ pattern in 1,2,4,5-tetrakis(bromomethyl)benzene (Jones & Kuś, 2007), which is also inversion-symmetric.

Details of the packing interactions are given in the Tables. The molecules pack in layers parallel to (101). Within the layers, the contacts Br1···Br2, the longer Br2···Br2 and the shorter H6A···Br2 are observed. These combine to form columns of interactions parallel to the b axis; chains of molecules parallel to [101] (horizontal in Fig. 2) are also formed. The contacts Br2···Br2 (the shorter), H6A···Br2 (the longer) and Br1···Cg (Cg = centre of gravity of the ring C1–5 and C1#1) link the layers (Fig. 3). H5···Br1 3.11 Å between the layers is a borderline interaction. The Br···Cg interaction could alternatively be interpreted as Br···C5, which at 3.450 (2) Å is by far the shortest of the six Br···C contacts; it is often unclear which is the better interpretation in such systems (Jones & Kuś, 2010). Despite the presence of the naphthalene ring systems, there are no significant Cg···Cg interactions. The shortest H···Cg contact is H7A···Cg (1 - x,1 - y,-z) 3.10 Å between layers, but this is both long and has a narrow angle (124°). We can conclude that the crystal packing of the title compound is dominated by the contacts involving bromomethylene groups.

Related literature top

For the use of 2,3,6,7-tetrakis(bromomethyl)naphthalene in the preparation of cyclophanes, see: Otsubo et al. (1983, 1989); Yano et al. (1999); Skibiński et al. (2009). For its applications in the synthesis of hydrogen-bonded molecular capsules, see: Valdes et al. (1995); Rivera et al. (2001). For reviews on halogen–halogen contacts and `weak' hydrogen bonding, see: Desiraju & Steiner (1999); Metrangolo & Resnati (2001); Metrangolo et al. (2008); Rissanen (2008). For the X-ray structures of the full series of ten isomeric bis(bromomethyl)naphthalenes, see: Jones & Kuś (2010). For the X-ray structures of two isomeric tetrakis(bromomethyl)benzene derivatives, see: Jones & Kuś (2007).

Experimental top

The title compound was prepared as described by Rivera et al. (2001) by treatment of a solution of 2,3-bis[{[(1,1-dimethylethyl)dimethylsilyl]oxy}methyl]- 6,7-bis[(phenylmethoxy)methyl]-naphthalene in chloroform with gaseous HBr. The compound was obtained as a colourless microcrystalline solid. Yield: 87%. Crystals suitable for X-ray diffraction were grown by slow evaporation of a solution in EtOH/hexane/CH2Cl2. M.p. (decomp.) 230–231° C (lit. 230° C). 1H NMR (CDCl3): δ = 7.83 (s, 4H), 4.84 (s, 8H) p.p.m..

The title compound is poorly soluble (< 1 g/L) in most organic solvents at room temperature, but is much more soluble in aromatic solvents, such as toluene or chlorobenzene, upon reflux.

Refinement top

Hydrogen atoms were included at calculated positions using a riding model with aromatic C—H 0.95, methylene C—H 0.99 Å. The U(H) values were fixed at 1.2 × Ueq(C) of the parent C atom.

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell refinement: CrysAlis PRO (Oxford Diffraction, 2009); data reduction: CrysAlis PRO (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP (Siemens, 1994); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Structure of the title compound in the crystal. Ellipsoids represent 50% probability levels. Only the asymmetric unit is numbered.
[Figure 2] Fig. 2. Molecular packing of the title compound as a layer parallel to (101). Br···Br and H···Br contacts are shown as thick dashed bonds.
[Figure 3] Fig. 3. Linking between the layers of the title compound. Br···Br and H···Br contacts are shown as thick dashed bonds. One representative Br···Cg contact is shown as a thin dashed bond (top left).
2,3,6,7-Tetrakis(bromomethyl)naphthalene top
Crystal data top
C14H12Br4Z = 1
Mr = 499.88F(000) = 236
Triclinic, P1Dx = 2.254 Mg m3
Hall symbol: -P 1Melting point: 503 K
a = 6.6144 (2) ÅMo Kα radiation, λ = 0.71073 Å
b = 7.1770 (2) ÅCell parameters from 9533 reflections
c = 8.7761 (3) Åθ = 2.4–30.7°
α = 84.744 (3)°µ = 10.91 mm1
β = 78.251 (3)°T = 100 K
γ = 64.555 (3)°Prism, colourless
V = 368.32 (2) Å30.20 × 0.06 × 0.04 mm
Data collection top
Oxford Diffraction Xcalibur Eos
diffractometer
2122 independent reflections
Radiation source: Enhance (Mo) X-ray Source1716 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.031
Detector resolution: 16.1419 pixels mm-1θmax = 30.0°, θmin = 2.4°
ω–scanh = 99
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2009)
k = 1010
Tmin = 0.356, Tmax = 1.000l = 1112
17701 measured reflections
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)] = 0.016Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.034H-atom parameters constrained
S = 0.92 w = 1/[σ2(Fo2) + (0.0181P)2]
where P = (Fo2 + 2Fc2)/3
2122 reflections(Δ/σ)max = 0.001
82 parametersΔρmax = 0.50 e Å3
0 restraintsΔρmin = 0.49 e Å3
Crystal data top
C14H12Br4γ = 64.555 (3)°
Mr = 499.88V = 368.32 (2) Å3
Triclinic, P1Z = 1
a = 6.6144 (2) ÅMo Kα radiation
b = 7.1770 (2) ŵ = 10.91 mm1
c = 8.7761 (3) ÅT = 100 K
α = 84.744 (3)°0.20 × 0.06 × 0.04 mm
β = 78.251 (3)°
Data collection top
Oxford Diffraction Xcalibur Eos
diffractometer
2122 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2009)
1716 reflections with I > 2σ(I)
Tmin = 0.356, Tmax = 1.000Rint = 0.031
17701 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0160 restraints
wR(F2) = 0.034H-atom parameters constrained
S = 0.92Δρmax = 0.50 e Å3
2122 reflectionsΔρmin = 0.49 e Å3
82 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
Br10.64988 (3)0.00387 (3)0.24985 (2)0.01628 (5)
Br20.23208 (3)0.72525 (3)0.44061 (2)0.01672 (5)
C10.0170 (3)0.4100 (3)0.02483 (19)0.0108 (3)
C20.0922 (3)0.2877 (3)0.14549 (19)0.0122 (3)
H20.06990.16720.17910.015*
C30.2297 (3)0.3393 (3)0.21518 (19)0.0111 (3)
C40.2621 (3)0.5223 (3)0.16547 (19)0.0110 (3)
C50.1575 (3)0.6419 (3)0.04994 (19)0.0112 (3)
H50.17910.76330.01850.013*
C60.3431 (3)0.2029 (3)0.34014 (19)0.0136 (3)
H6A0.24950.13160.39450.016*
H6B0.35630.28760.41730.016*
C70.4062 (3)0.5854 (3)0.24055 (18)0.0135 (3)
H7A0.45590.67990.17040.016*
H7B0.54370.46200.25920.016*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.01360 (10)0.01494 (10)0.01724 (10)0.00349 (8)0.00312 (7)0.00232 (7)
Br20.01615 (10)0.01865 (11)0.01468 (9)0.00544 (8)0.00321 (7)0.00581 (7)
C10.0099 (8)0.0112 (9)0.0093 (8)0.0031 (7)0.0001 (6)0.0012 (6)
C20.0130 (8)0.0120 (9)0.0105 (8)0.0053 (7)0.0000 (7)0.0003 (6)
C30.0085 (8)0.0127 (9)0.0087 (8)0.0016 (7)0.0006 (6)0.0008 (6)
C40.0092 (8)0.0139 (9)0.0097 (8)0.0050 (7)0.0011 (6)0.0040 (6)
C50.0111 (8)0.0104 (8)0.0120 (8)0.0055 (7)0.0012 (6)0.0020 (6)
C60.0111 (8)0.0156 (9)0.0115 (8)0.0033 (7)0.0017 (7)0.0003 (7)
C70.0128 (8)0.0177 (9)0.0101 (8)0.0064 (7)0.0017 (7)0.0023 (7)
Geometric parameters (Å, º) top
Br1—C61.9801 (16)C4—C71.493 (2)
Br2—C71.9806 (16)C5—C1i1.422 (2)
C1—C21.418 (2)C2—H20.9500
C1—C1i1.420 (3)C5—H50.9500
C1—C5i1.422 (2)C6—H6A0.9900
C2—C31.377 (2)C6—H6B0.9900
C3—C41.436 (2)C7—H7A0.9900
C3—C61.494 (2)C7—H7B0.9900
C4—C51.363 (2)
C2—C1—C1i118.85 (18)C1—C2—H2119.2
C2—C1—C5i122.57 (15)C4—C5—H5119.0
C1i—C1—C5i118.58 (19)C1i—C5—H5119.0
C3—C2—C1121.68 (15)C3—C6—H6A109.6
C2—C3—C4119.29 (15)Br1—C6—H6A109.6
C2—C3—C6119.30 (15)C3—C6—H6B109.6
C4—C3—C6121.41 (15)Br1—C6—H6B109.6
C5—C4—C3119.70 (15)H6A—C6—H6B108.1
C5—C4—C7119.52 (15)C4—C7—H7A109.6
C3—C4—C7120.77 (15)Br2—C7—H7A109.6
C4—C5—C1i121.90 (15)C4—C7—H7B109.6
C3—C6—Br1110.35 (11)Br2—C7—H7B109.6
C4—C7—Br2110.18 (11)H7A—C7—H7B108.1
C3—C2—H2119.2
C1i—C1—C2—C30.0 (3)C6—C3—C4—C71.7 (2)
C5i—C1—C2—C3179.24 (16)C3—C4—C5—C1i0.5 (2)
C1—C2—C3—C40.5 (2)C7—C4—C5—C1i179.53 (15)
C1—C2—C3—C6179.09 (15)C2—C3—C6—Br192.22 (16)
C2—C3—C4—C50.2 (2)C4—C3—C6—Br187.36 (16)
C6—C3—C4—C5179.34 (15)C5—C4—C7—Br299.15 (16)
C2—C3—C4—C7178.76 (15)C3—C4—C7—Br279.86 (17)
Symmetry code: (i) x, y+1, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6A···Br2ii0.992.963.7967 (17)143
C6—H6A···Br2iii0.992.983.7359 (16)134
C5—H5···Br1iv0.953.113.9399 (16)147
Symmetry codes: (ii) x, y1, z; (iii) x, y+1, z+1; (iv) x+1, y+1, z.

Experimental details

Crystal data
Chemical formulaC14H12Br4
Mr499.88
Crystal system, space groupTriclinic, P1
Temperature (K)100
a, b, c (Å)6.6144 (2), 7.1770 (2), 8.7761 (3)
α, β, γ (°)84.744 (3), 78.251 (3), 64.555 (3)
V3)368.32 (2)
Z1
Radiation typeMo Kα
µ (mm1)10.91
Crystal size (mm)0.20 × 0.06 × 0.04
Data collection
DiffractometerOxford Diffraction Xcalibur Eos
diffractometer
Absorption correctionMulti-scan
(CrysAlis PRO; Oxford Diffraction, 2009)
Tmin, Tmax0.356, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
17701, 2122, 1716
Rint0.031
(sin θ/λ)max1)0.704
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.016, 0.034, 0.92
No. of reflections2122
No. of parameters82
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.50, 0.49

Computer programs: CrysAlis PRO (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP (Siemens, 1994).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6A···Br2i0.992.963.7967 (17)143.4
C6—H6A···Br2ii0.992.983.7359 (16)134.0
C5—H5···Br1iii0.953.113.9399 (16)147.2
Symmetry codes: (i) x, y1, z; (ii) x, y+1, z+1; (iii) x+1, y+1, z.
Bromine–bromine and related contacts and angles (Å, °) top
Cg is the centroid of the C1–C5,C1(-x, 1-y, -z) ring.
System C—Br···Br—C or C—Br···CgBr···Br or Br···CgC—Br···Br (or C—Br···Cg), Br···Br—COperator
C6—Br1···Br2—C73.8972 (3)76.45 (5), 134.79 (5)1-x, 1-y, 1-z
C7—Br2···Br2—C73.8873 (4)134.93 (5) × 2-x, 2-y, 1-z
C7—Br2···Br2—C73.8913 (4)76.72 (5) × 21-x, 1-y, 1-z
C6—Br1···Cg3.891581+x, -1+y, z
 

Acknowledgements

We are grateful to Dr P. Kuś, Silesian University, Katowice, Poland, for crystallizing the title compound.

References

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ISSN: 2056-9890
Volume 66| Part 7| July 2010| Pages o1846-o1847
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