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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

N,N′-Bis(4-chloro­benzyl­­idene)-2,2-di­methyl­propane-1,3-di­amine

aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and bDepartment of Chemistry, School of Science, Payame Noor University, Ardakan, Yazd, Iran
*Correspondence e-mail: hkfun@usm.my

(Received 28 October 2008; accepted 29 October 2008; online 8 November 2008)

The title compound, C19H20Cl2N2, is a potential bidentate Schiff base ligand. Intra­molecular C—H⋯N hydrogen bonds form five-membered rings, generating S(5) ring motifs. Each imino functional group is coplanar with its adjacent benzene ring; the two benzene rings form a dihedral angle of 51.30 (4)°. An inter­esting feature of the crystal structure is weak inter­molecular Cl⋯Cl [3.4752 (4) Å] and Cl⋯N [3.2927 (9) Å] inter­actions. Inter­molecular Cl⋯N inter­actions link mol­ecules into dimers with R22(22) ring motifs. The crystal structure is further stabilized by weak ππ [centroid–centroid distances = 3.6970 (6)–3.8560 (6) Å] inter­actions.

Related literature

For hydrogen-bond motifs, see Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chamg, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]). For related structures see, for example: Li et al. (2005[Li, Y.-G., Zhu, H.-L., Chen, X.-Z. & Song, Y. (2005). Acta Cryst. E61, o4156-o4157.]); Bomfim et al. (2005[Bomfim, J. A. S., Wardell, J. L., Low, J. N., Skakle, J. M. S. & Glidewell, C. (2005). Acta Cryst. C61, o53-o56.]); Glidewell et al. (2005[Glidewell, C., Low, J. N., Skakle, J. M. S. & Wardell, J. L. (2005). Acta Cryst. E61, o3551-o3553.], 2006[Glidewell, C., Low, J. N., Skakle, J. M. S. & Wardell, J. L. (2006). Acta Cryst. C62, o1-o4.]); Sun et al. (2004[Sun, Y.-X., You, Z.-L. & Zhu, H.-L. (2004). Acta Cryst. E60, o1707-o1708.]); Fun et al. (2008[Fun, H.-K., Kargar, H. & Kia, R. (2008). Acta Cryst. E64, o1308.]).

[Scheme 1]

Experimental

Crystal data
  • C19H20Cl2N2

  • Mr = 347.27

  • Monoclinic, P 21 /c

  • a = 19.6392 (3) Å

  • b = 9.3275 (2) Å

  • c = 9.7841 (2) Å

  • β = 92.213 (1)°

  • V = 1790.96 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.36 mm−1

  • T = 100 (1) K

  • 0.51 × 0.35 × 0.10 mm

Data collection
  • Bruker SMART APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.836, Tmax = 0.966

  • 21670 measured reflections

  • 6419 independent reflections

  • 5273 reflections with I > 2σ(I)

  • Rint = 0.028

Refinement
  • R[F2 > 2σ(F2)] = 0.036

  • wR(F2) = 0.095

  • S = 1.03

  • 6419 reflections

  • 208 parameters

  • H-atom parameters constrained

  • Δρmax = 0.38 e Å−3

  • Δρmin = −0.32 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C18—H18B⋯N1 0.96 2.60 2.9346 (15) 101
C19—H19C⋯N2 0.96 2.61 2.9416 (15) 101

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: APEX2 and SAINT (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]).

Supporting information


Comment top

Schiff bases are one of most prevalent mixed-donor ligands in the field of coordination chemistry. They play an important role in the development of coordination chemistry related to catalysis and enzymatic reactions, magnetism, and supramolecular architectures. Structures of Schiff-base compounds derived from substituted benzaldehydes and closely related to the title compound, (I), have been reported previously (Li et al., 2005; Bomfim et al., 2005; Glidewell et al., 2005, 2006; Sun et al., 2004; Fun et al., 2008).

In (I), Fig. 1, each imino functional group is co-planar with its adjacent benzene ring. Intramolecular C—H···N hydrogen bonds form five-membered rings, Fig. 1, producing S(5) ring motifs (Bernstein et al., 1995). The two benzene rings form a dihedral angle of 51.30 (4)°. The interesting feature of the crystal structure is the presence of weak intermolecular Cl···Cl [3.4852 (3) Å; symmetry code: x, 1 - y, -1/2 + z] and Cl···N [3.2927 (9) Å; symmetry code: -x, 1 - y, 1 - z] interactions. The intermolecular Cl···N interactions link neighbouring molecules into dimers with R22(22) ring motifs (Bernstein et al., 1995). The crystal structure is further stabilized by weak intermolecular ππ interactions [Cg1···Cg1= 3.8560 (6) Å; symmetry code: 1 - x, 1 - y, 1 - z; Cg2···Cg2 = 3.6970 (6) Å; symmetry code: -x, 1 - y, 1 - z] (Cg1 and Cg2 are the centroids of the C1–C6 and C12–C17 rings, respectively.

Related literature top

For hydrogen-bond motifs, see Bernstein et al. (1995). For related structures see, for example: Li et al. (2005); Bomfim et al. (2005); Glidewell et al. (2005, 2006); Sun et al. (2004); Fun et al. (2008).

Experimental top

The synthetic method has been described earlier (Fun et al., 2008). Single crystals suitable for X-ray diffraction were obtained by evaporation of an ethanol solution of (I) held at room temperature.

Refinement top

All H atoms were included in the riding model approximation with C—H = 0.93 - 0.97 Å, and with U(H) = 1.2–1.5 times Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: APEX2 (Bruker, 2005) and SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2003).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) showing atom labels and 50% probability ellipsoids for non-H atoms. Intramolecular hydrogen bonds are shown as dashed lines.
N,N'-Bis(4-dichlorobenzylidene)-2,2-dimethylpropane-1,3-diamine top
Crystal data top
C19H20Cl2N2F(000) = 728
Mr = 347.27Dx = 1.288 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 8119 reflections
a = 19.6392 (3) Åθ = 3.0–38.9°
b = 9.3275 (2) ŵ = 0.36 mm1
c = 9.7841 (2) ÅT = 100 K
β = 92.213 (1)°Plate, colourless
V = 1790.96 (6) Å30.51 × 0.35 × 0.10 mm
Z = 4
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
6419 independent reflections
Radiation source: fine-focus sealed tube5273 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.028
ϕ and ω scansθmax = 32.5°, θmin = 1.0°
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
h = 2929
Tmin = 0.836, Tmax = 0.966k = 1412
21670 measured reflectionsl = 1414
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)] = 0.036Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.095H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0434P)2 + 0.5329P]
where P = (Fo2 + 2Fc2)/3
6419 reflections(Δ/σ)max = 0.001
208 parametersΔρmax = 0.38 e Å3
0 restraintsΔρmin = 0.32 e Å3
Crystal data top
C19H20Cl2N2V = 1790.96 (6) Å3
Mr = 347.27Z = 4
Monoclinic, P21/cMo Kα radiation
a = 19.6392 (3) ŵ = 0.36 mm1
b = 9.3275 (2) ÅT = 100 K
c = 9.7841 (2) Å0.51 × 0.35 × 0.10 mm
β = 92.213 (1)°
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
6419 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
5273 reflections with I > 2σ(I)
Tmin = 0.836, Tmax = 0.966Rint = 0.028
21670 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0360 restraints
wR(F2) = 0.095H-atom parameters constrained
S = 1.03Δρmax = 0.38 e Å3
6419 reflectionsΔρmin = 0.32 e Å3
208 parameters
Special details top

Experimental. The low-temperature data was collected with the Oxford Cyrosystem Cobra low-temperature attachment.

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
Cl10.497643 (14)0.49166 (3)0.17717 (3)0.02553 (7)
Cl20.166144 (13)0.43828 (3)0.54241 (3)0.02640 (7)
N10.28500 (4)0.54904 (10)0.70403 (9)0.01950 (17)
N20.14528 (4)0.37002 (10)0.85655 (9)0.01864 (17)
C10.35398 (5)0.47808 (13)0.45572 (11)0.0216 (2)
H1A0.31550.42380.47310.026*
C20.39180 (6)0.44677 (13)0.34258 (11)0.0226 (2)
H2A0.37910.37200.28420.027*
C30.44914 (5)0.52935 (12)0.31802 (11)0.01962 (19)
C40.46927 (5)0.64046 (12)0.40359 (11)0.0208 (2)
H4A0.50800.69390.38630.025*
C50.43069 (5)0.67111 (12)0.51594 (11)0.01929 (19)
H5A0.44340.74660.57350.023*
C60.37302 (5)0.59009 (11)0.54371 (10)0.01710 (18)
C70.33470 (5)0.62450 (12)0.66609 (11)0.01815 (19)
H7A0.34740.70460.71760.022*
C80.25179 (5)0.59532 (12)0.82751 (11)0.0202 (2)
H8A0.20460.61870.80480.024*
H8B0.27400.68130.86280.024*
C90.25474 (5)0.47832 (12)0.93875 (11)0.01860 (19)
C100.21738 (5)0.34242 (12)0.88813 (11)0.01881 (19)
H10A0.23860.30700.80680.023*
H10B0.22160.26880.95790.023*
C110.12219 (5)0.33583 (11)0.73837 (11)0.01765 (18)
H11A0.15150.29360.67770.021*
C120.05057 (5)0.36042 (11)0.69311 (10)0.01656 (18)
C130.00695 (5)0.44318 (12)0.77071 (11)0.01855 (19)
H13A0.02300.48320.85290.022*
C140.06007 (5)0.46587 (12)0.72583 (11)0.01985 (19)
H14A0.08910.52070.77740.024*
C150.08314 (5)0.40546 (12)0.60260 (11)0.01940 (19)
C160.04087 (5)0.32318 (12)0.52386 (11)0.0204 (2)
H16A0.05710.28320.44180.024*
C170.02632 (5)0.30141 (12)0.56973 (11)0.01898 (19)
H17A0.05530.24700.51750.023*
C180.32900 (5)0.43799 (14)0.97383 (12)0.0249 (2)
H18A0.35340.52141.00580.037*
H18B0.34970.40140.89370.037*
H18C0.33040.36601.04400.037*
C190.22142 (6)0.53832 (14)1.06574 (12)0.0261 (2)
H19A0.24520.62311.09600.039*
H19B0.22350.46781.13720.039*
H19C0.17470.56161.04350.039*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.02940 (13)0.02639 (15)0.02128 (12)0.00830 (10)0.00692 (10)0.00370 (10)
Cl20.01662 (11)0.02663 (15)0.03566 (15)0.00011 (9)0.00260 (9)0.00411 (11)
N10.0189 (4)0.0204 (4)0.0192 (4)0.0005 (3)0.0014 (3)0.0005 (3)
N20.0146 (3)0.0200 (4)0.0215 (4)0.0014 (3)0.0025 (3)0.0000 (3)
C10.0202 (4)0.0231 (5)0.0214 (5)0.0044 (4)0.0001 (4)0.0006 (4)
C20.0251 (5)0.0231 (5)0.0197 (5)0.0028 (4)0.0007 (4)0.0026 (4)
C30.0221 (4)0.0194 (5)0.0175 (4)0.0048 (4)0.0024 (4)0.0038 (4)
C40.0199 (4)0.0176 (5)0.0250 (5)0.0003 (4)0.0039 (4)0.0043 (4)
C50.0195 (4)0.0154 (5)0.0230 (5)0.0013 (3)0.0012 (4)0.0006 (4)
C60.0169 (4)0.0167 (5)0.0177 (4)0.0001 (3)0.0004 (3)0.0023 (4)
C70.0178 (4)0.0174 (5)0.0191 (4)0.0002 (3)0.0002 (3)0.0007 (4)
C80.0185 (4)0.0197 (5)0.0226 (5)0.0003 (4)0.0044 (4)0.0008 (4)
C90.0162 (4)0.0215 (5)0.0182 (4)0.0019 (3)0.0019 (3)0.0015 (4)
C100.0158 (4)0.0191 (5)0.0216 (5)0.0002 (3)0.0018 (3)0.0000 (4)
C110.0165 (4)0.0160 (5)0.0207 (5)0.0005 (3)0.0049 (3)0.0005 (4)
C120.0161 (4)0.0153 (4)0.0184 (4)0.0005 (3)0.0028 (3)0.0019 (3)
C130.0190 (4)0.0185 (5)0.0183 (5)0.0007 (3)0.0033 (3)0.0006 (4)
C140.0180 (4)0.0189 (5)0.0230 (5)0.0017 (4)0.0046 (4)0.0015 (4)
C150.0156 (4)0.0177 (5)0.0249 (5)0.0010 (3)0.0005 (3)0.0049 (4)
C160.0215 (4)0.0195 (5)0.0202 (5)0.0020 (4)0.0003 (4)0.0008 (4)
C170.0194 (4)0.0180 (5)0.0197 (5)0.0007 (3)0.0029 (3)0.0006 (4)
C180.0186 (4)0.0303 (6)0.0255 (5)0.0024 (4)0.0025 (4)0.0008 (4)
C190.0272 (5)0.0292 (6)0.0222 (5)0.0042 (4)0.0065 (4)0.0055 (4)
Geometric parameters (Å, º) top
Cl1—C31.7411 (11)C9—C191.5323 (15)
Cl2—C151.7390 (10)C9—C101.5370 (15)
N1—C71.2703 (13)C10—H10A0.9700
N1—C81.4602 (14)C10—H10B0.9700
N2—C111.2664 (14)C11—C121.4761 (14)
N2—C101.4603 (13)C11—H11A0.9300
C1—C21.3876 (15)C12—C171.3939 (15)
C1—C61.3956 (15)C12—C131.3987 (14)
C1—H1A0.9300C13—C141.3876 (14)
C2—C31.3929 (15)C13—H13A0.9300
C2—H2A0.9300C14—C151.3908 (16)
C3—C41.3805 (16)C14—H14A0.9300
C4—C51.3886 (14)C15—C161.3860 (15)
C4—H4A0.9300C16—C171.3921 (14)
C5—C61.3970 (14)C16—H16A0.9300
C5—H5A0.9300C17—H17A0.9300
C6—C71.4741 (14)C18—H18A0.9600
C7—H7A0.9300C18—H18B0.9600
C8—C91.5408 (16)C18—H18C0.9600
C8—H8A0.9700C19—H19A0.9600
C8—H8B0.9700C19—H19B0.9600
C9—C181.5322 (15)C19—H19C0.9600
C7—N1—C8116.79 (9)C9—C10—H10A109.3
C11—N2—C10117.31 (9)N2—C10—H10B109.3
C2—C1—C6120.72 (10)C9—C10—H10B109.3
C2—C1—H1A119.6H10A—C10—H10B107.9
C6—C1—H1A119.6N2—C11—C12122.56 (9)
C1—C2—C3118.84 (10)N2—C11—H11A118.7
C1—C2—H2A120.6C12—C11—H11A118.7
C3—C2—H2A120.6C17—C12—C13119.48 (9)
C4—C3—C2121.67 (10)C17—C12—C11119.22 (9)
C4—C3—Cl1118.62 (8)C13—C12—C11121.30 (9)
C2—C3—Cl1119.71 (9)C14—C13—C12120.38 (10)
C3—C4—C5118.84 (10)C14—C13—H13A119.8
C3—C4—H4A120.6C12—C13—H13A119.8
C5—C4—H4A120.6C13—C14—C15119.07 (10)
C4—C5—C6120.92 (10)C13—C14—H14A120.5
C4—C5—H5A119.5C15—C14—H14A120.5
C6—C5—H5A119.5C16—C15—C14121.61 (9)
C1—C6—C5119.00 (9)C16—C15—Cl2118.88 (9)
C1—C6—C7122.08 (9)C14—C15—Cl2119.47 (8)
C5—C6—C7118.91 (9)C15—C16—C17118.83 (10)
N1—C7—C6122.61 (10)C15—C16—H16A120.6
N1—C7—H7A118.7C17—C16—H16A120.6
C6—C7—H7A118.7C16—C17—C12120.63 (9)
N1—C8—C9111.67 (9)C16—C17—H17A119.7
N1—C8—H8A109.3C12—C17—H17A119.7
C9—C8—H8A109.3C9—C18—H18A109.5
N1—C8—H8B109.3C9—C18—H18B109.5
C9—C8—H8B109.3H18A—C18—H18B109.5
H8A—C8—H8B107.9C9—C18—H18C109.5
C18—C9—C19109.91 (9)H18A—C18—H18C109.5
C18—C9—C10107.95 (9)H18B—C18—H18C109.5
C19—C9—C10110.43 (8)C9—C19—H19A109.5
C18—C9—C8109.97 (8)C9—C19—H19B109.5
C19—C9—C8107.97 (9)H19A—C19—H19B109.5
C10—C9—C8110.61 (9)C9—C19—H19C109.5
N2—C10—C9111.70 (9)H19A—C19—H19C109.5
N2—C10—H10A109.3H19B—C19—H19C109.5
C6—C1—C2—C30.13 (17)C11—N2—C10—C9125.72 (10)
C1—C2—C3—C40.35 (17)C18—C9—C10—N2178.07 (9)
C1—C2—C3—Cl1179.70 (9)C19—C9—C10—N257.90 (12)
C2—C3—C4—C50.74 (17)C8—C9—C10—N261.57 (11)
Cl1—C3—C4—C5179.89 (8)C10—N2—C11—C12178.94 (9)
C3—C4—C5—C60.93 (16)N2—C11—C12—C17170.66 (10)
C2—C1—C6—C50.31 (17)N2—C11—C12—C1310.16 (16)
C2—C1—C6—C7178.88 (10)C17—C12—C13—C140.35 (16)
C4—C5—C6—C10.72 (16)C11—C12—C13—C14179.52 (10)
C4—C5—C6—C7178.50 (10)C12—C13—C14—C150.14 (16)
C8—N1—C7—C6179.80 (9)C13—C14—C15—C160.08 (16)
C1—C6—C7—N14.79 (16)C13—C14—C15—Cl2177.78 (8)
C5—C6—C7—N1174.40 (10)C14—C15—C16—C170.23 (16)
C7—N1—C8—C9120.74 (10)Cl2—C15—C16—C17177.64 (8)
N1—C8—C9—C1857.83 (12)C15—C16—C17—C120.44 (16)
N1—C8—C9—C19177.75 (8)C13—C12—C17—C160.51 (16)
N1—C8—C9—C1061.31 (11)C11—C12—C17—C16179.70 (10)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C18—H18B···N10.962.602.9346 (15)101
C19—H19C···N20.962.612.9416 (15)101

Experimental details

Crystal data
Chemical formulaC19H20Cl2N2
Mr347.27
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)19.6392 (3), 9.3275 (2), 9.7841 (2)
β (°) 92.213 (1)
V3)1790.96 (6)
Z4
Radiation typeMo Kα
µ (mm1)0.36
Crystal size (mm)0.51 × 0.35 × 0.10
Data collection
DiffractometerBruker SMART APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.836, 0.966
No. of measured, independent and
observed [I > 2σ(I)] reflections
21670, 6419, 5273
Rint0.028
(sin θ/λ)max1)0.756
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.036, 0.095, 1.03
No. of reflections6419
No. of parameters208
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.38, 0.32

Computer programs: , APEX2 (Bruker, 2005) and SAINT (Bruker, 2005), SAINT (Bruker, 2005), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2003).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C18—H18B···N10.962.602.9346 (15)101
C19—H19C···N20.962.612.9416 (15)101
 

Footnotes

Additional correspondence author, e-mail: hkargar@pnu.ac.ir.

Acknowledgements

HKF and RK thank the Malaysian Government and Universiti Sains Malaysia for Science Fund grant No. 305/PFIZIK/613312. RK thanks Universiti Sains Malaysia for a post-doctoral research fellowship. HK thanks Payame Noor University for financial support.

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