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

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1,1′-[2,3,5,6-Tetra­methyl-p-phenyl­ene­bis­(methyl­ene­oxy)]di-1H-benzotriazole

aDepartment of Chemistry, Popes College, Sawyerpuram 628 251, Tamilnadu, India, bDepartment of Physics, Karunya University, Karunya Nagar, Coimbatore 641 114, India, and cInstitut für Organische Chemie, Universität Mainz, Duesbergweg 10-14, 55099 Mainz, Germany
*Correspondence e-mail: b_ravidurai@yahoo.com

(Received 23 March 2009; accepted 24 March 2009; online 28 March 2009)

The complete molecule of the title compound, C24H24N6O2, is generated by a crystallographic inversion centre. The benzotriazole rings form dihedral angles of 2.10 (7)° with the central aromatic ring. The crystal packing is consolidated by ππ inter­actions, with centroid–centroid distances of 3.6234 (10) Å, together with weak C—H⋯π inter­actions.

Related literature

For the biological activity of N-oxide and benzotriazole derivatives see: Katarzyna et al.(2005[Katarzyna, K., Najda, A., Zebrowska, J., Chomicz, L., Piekarczyk, J., Myjak, P. & Bretner, M. (2005). Bioorg. Med. Chem. 13, 3601-3616.]); Sarala et al. (2007[Sarala, G., Swamy, S. N., Prabhuswamy, B., Andalwar, S. M., Prasad, J. S. & Rangappa, K. S. (2007). Anal. Sci. 23, 25-26.]). For applications of benzotriazole, see: Kopec et al. (2008[Kopec, E. A., Zwolska, Z. & Kazimierczuk, A. O. Z. (2008). Acta Pol. Pharm. Drug Res. 65, 435-439.]); Krawczyk & Gdaniec (2005[Krawczyk, S. & Gdaniec, M. (2005). Acta Cryst. E61, o2967-o2969.]); Smith et al. (2001[Smith, G., Bottle, S. E., Reid, D. A., Schweinsberg, D. P. & Bott, R. C. (2001). Acta Cryst. E57, o531-o532.]); Sha et al. (1996[Sha, G., Wang, W. & Ren, T. (1996). Mocha Xuebao, 16, 344-350.]). For 1-hydroxy­benzotriazole, see: Anderson et al. (1963[Anderson, G. W., Zimmerman, J. E. & Calahan, F. M. (1963). J. Am. Chem. Soc. 85, 3039-3039.]); Bosch et al. (1983[Bosch, R., Jung, G. & Winter, W. (1983). Acta Cryst. C39, 1089-1092.]).

[Scheme 1]

Experimental

Crystal data
  • C24H24N6O2

  • Mr = 428.49

  • Monoclinic, P 21 /c

  • a = 9.3895 (6) Å

  • b = 7.5960 (2) Å

  • c = 15.7471 (13) Å

  • β = 110.770 (3)°

  • V = 1050.13 (11) Å3

  • Z = 2

  • Cu Kα radiation

  • μ = 0.73 mm−1

  • T = 193 K

  • 0.51 × 0.26 × 0.19 mm

Data collection
  • Enraf–Nonius CAD-4 diffractometer

  • Absorption correction: ψ scan (CORINC; Draeger & Gattow, 1971[Draeger, M. & Gattow, G. (1971). Acta Chem. Scand. 25, 761-762.]) Tmin = 0.707, Tmax = 0.873

  • 2075 measured reflections

  • 1996 independent reflections

  • 1905 reflections with I > 2σ(I)

  • Rint = 0.026

  • 3 standard reflections frequency: 60 min intensity decay: 1%

Refinement
  • R[F2 > 2σ(F2)] = 0.052

  • wR(F2) = 0.147

  • S = 1.10

  • 1996 reflections

  • 147 parameters

  • H-atom parameters constrained

  • Δρmax = 0.32 e Å−3

  • Δρmin = −0.33 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C6—H6⋯Cg2i 0.95 2.82 3.700 (2) 154
Symmetry code: (i) [-x, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]. Cg2 is the centroid of the C4–C9 ring.

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994[Enraf-Nonius (1994). CAD-4 EXPRESS. Enraf-Nonius, Delft, The Netherlands.]); cell refinement: CAD-4 EXPRESS; data reduction: CORINC (Draeger & Gattow, 1971[Draeger, M. & Gattow, G. (1971). Acta Chem. Scand. 25, 761-762.]); 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Benzotriazole derivatives show biological activities such as anti-inflammatory, diuretic, antiviral and antihypertensive agents (Katarzyna et al., 2005; Sarala et al., 2007). It is used as a corrosion inhibitor, antifreeze agent, ultraviolet light stabilizer for plastics and as an antifoggant in photography (Krawczyk & Gdaniec, 2005; Smith et al., 2001). N-aryloxy derivatives of benzotriazoles have antimycobacterial activity (Kopec et al., 2008). Benzotriazole possessing three vicinal N atoms, is used as an antifouling and antiwear reagent (Sha et al., 1996). 1-Hydroxybenzotriazole is widely being used as a reagent for peptide synthesis (Anderson et al., 1963). The crystal structure of benzotriazole 1-oxide has been reported (Bosch et al., 1983). Due to the above mentioned applications of benzotriazole we have synthesized and report here the crystal structure of the title compound (I).

The asymmetric unit of (I) comprises of half molecule of the title compound (Fig. 1), the other half is symmetry generated [symmetry code: 1 - x,1 - y,1 - z]. The benzotriazole ring is essentially planar with the maximum deviation from planarity being 0.015 (18) Å for atom C8. The mean plane of the benzotriazole rings (N1—N3/C4—C9; N1A—N3A/C4A—C9A) forming a dihedral angles of 2.10 (7)° and 2.09 (7)° respectively, with the phenyl ring (C12 - C14/C12A-C14A), indicating that all the three are almost coplanar.

The crystal packing (Fig.2) is stabilized by ππ stacking interactions [Cg2—Cg3i= 3.6234 (10) Å; Cg2: (C4—C9); Cg3:(C12—C14/C12A—C14A): Symmetry code: (i) x, -1 + y, z]; [Cg2—Cg3ii= 3.6234 (10) Å; Cg2: (C4—C9); Cg3:(C12—C14/C12A—C14A): Symmetry code: (ii) 1 - x, -y,1 - z] together with weak C—H···π interactions. (Fig.2).

Related literature top

For the biological activity of N-oxide and benzotriazole derivatives see: Katarzyna et al.(2005); Sarala et al. (2007). For applications of benzotriazole, see: Kopec et al. (2008); Krawczyk & Gdaniec (2005); Smith et al. (2001); Sha et al. (1996). For 1-hydroxybenzotriazole, see: Anderson et al. (1963); Bosch et al. (1983). Cg2 is the centroid of the C4–C9 ring.

Experimental top

A mixture of 1,4-bis(bromomethyl)-2,3,5,6-tetramethyl-benzene (0.320 g, 1 mmol) and sodium salt of 1-hydroxybenzotriazole (0.314 2 mmol) in ethanol (10 ml) was heated at 333 K with stirring for 30 min. The product formed was filtered off and dried. The product was dissolved in ethanol and on slow evaporation crystals suitable for x-ray diffraction are obtained.

Refinement top

All the H atoms were positioned geometrically (Caromatic—H=0.95 Å, Cmethyl—H=0.98 or Cmethylene—H=0.99 Å) and refined using a riding model with, Uiso(H)=1.2Ueq(C) and 1.5Ueq(Cmethyl). A rotating group model was used for the methyl groups.

Computing details top

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS (Enraf–Nonius, 1994); data reduction: CORINC (Draeger & Gattow, 1971); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atom numbering scheme [symmetry code: -x + 1,-y + 1,-z + 1].
[Figure 2] Fig. 2. The crystal packing of the title compound, viewed down the c axis.
1,1'-[2,3,5,6-Tetramethyl-p-phenylenebis(methyleneoxy)]di-1H- benzotriazole top
Crystal data top
C24H24N6O2F(000) = 452
Mr = 428.49Dx = 1.355 Mg m3
Monoclinic, P21/cCu Kα radiation, λ = 1.54178 Å
Hall symbol: -P 2ybcCell parameters from 25 reflections
a = 9.3895 (6) Åθ = 65–70°
b = 7.5960 (2) ŵ = 0.73 mm1
c = 15.7471 (13) ÅT = 193 K
β = 110.770 (3)°Block, colourless
V = 1050.13 (11) Å30.51 × 0.26 × 0.19 mm
Z = 2
Data collection top
Enraf–Nonius CAD-4
diffractometer
1905 reflections with I > 2σ(I)
Radiation source: rotating anodeRint = 0.026
Graphite monochromatorθmax = 70.0°, θmin = 5.0°
ω/2θ scansh = 1110
Absorption correction: ψ scan
(CORINC; Draeger & Gattow, 1971)
k = 09
Tmin = 0.707, Tmax = 0.873l = 019
2075 measured reflections3 standard reflections every 60 min
1996 independent reflections intensity decay: 1%
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)] = 0.052Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.147H-atom parameters constrained
S = 1.10 w = 1/[σ2(Fo2) + (0.0832P)2 + 0.5P]
where P = (Fo2 + 2Fc2)/3
1996 reflections(Δ/σ)max < 0.001
147 parametersΔρmax = 0.32 e Å3
0 restraintsΔρmin = 0.33 e Å3
Crystal data top
C24H24N6O2V = 1050.13 (11) Å3
Mr = 428.49Z = 2
Monoclinic, P21/cCu Kα radiation
a = 9.3895 (6) ŵ = 0.73 mm1
b = 7.5960 (2) ÅT = 193 K
c = 15.7471 (13) Å0.51 × 0.26 × 0.19 mm
β = 110.770 (3)°
Data collection top
Enraf–Nonius CAD-4
diffractometer
1905 reflections with I > 2σ(I)
Absorption correction: ψ scan
(CORINC; Draeger & Gattow, 1971)
Rint = 0.026
Tmin = 0.707, Tmax = 0.8733 standard reflections every 60 min
2075 measured reflections intensity decay: 1%
1996 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0520 restraints
wR(F2) = 0.147H-atom parameters constrained
S = 1.10Δρmax = 0.32 e Å3
1996 reflectionsΔρmin = 0.33 e Å3
147 parameters
Special details top

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 > 2sigma(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
N10.25022 (16)0.07614 (18)0.47932 (9)0.0302 (3)
N20.17398 (19)0.1201 (2)0.53429 (10)0.0385 (4)
N30.08837 (19)0.2555 (2)0.49841 (11)0.0408 (4)
C40.10897 (19)0.2985 (2)0.41828 (12)0.0317 (4)
C50.0438 (2)0.4308 (2)0.35473 (14)0.0396 (4)
H50.02760.51180.36270.047*
C60.0873 (2)0.4389 (3)0.28015 (13)0.0408 (5)
H60.04380.52640.23530.049*
C70.1948 (2)0.3209 (2)0.26842 (12)0.0380 (4)
H70.22120.33090.21570.046*
C80.26238 (19)0.1922 (2)0.33068 (12)0.0321 (4)
H80.33670.11460.32350.039*
C90.21514 (17)0.1820 (2)0.40554 (11)0.0270 (4)
O100.34983 (13)0.06259 (15)0.50086 (8)0.0317 (3)
C110.27184 (18)0.2246 (2)0.45748 (11)0.0296 (4)
H11A0.19070.25610.48120.036*
H11B0.22530.20870.39090.036*
C120.39164 (17)0.3661 (2)0.48003 (10)0.0248 (4)
C130.47071 (18)0.3997 (2)0.42060 (10)0.0259 (4)
C140.42305 (17)0.4639 (2)0.55983 (10)0.0255 (4)
C150.4428 (2)0.2893 (2)0.33658 (12)0.0381 (4)
H15A0.37970.35540.28300.057*
H15B0.39010.18060.34160.057*
H15C0.54040.26010.33050.057*
C160.3446 (2)0.4206 (3)0.62620 (13)0.0397 (5)
H16A0.41830.42830.68840.060*
H16B0.30320.30090.61470.060*
H16C0.26160.50440.61850.060*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0380 (7)0.0273 (7)0.0337 (7)0.0030 (6)0.0229 (6)0.0022 (5)
N20.0543 (9)0.0351 (8)0.0403 (8)0.0001 (7)0.0344 (7)0.0050 (6)
N30.0532 (9)0.0338 (8)0.0513 (9)0.0041 (7)0.0383 (8)0.0039 (7)
C40.0330 (8)0.0285 (8)0.0417 (9)0.0010 (6)0.0231 (7)0.0057 (7)
C50.0331 (9)0.0320 (9)0.0582 (12)0.0044 (7)0.0219 (8)0.0012 (8)
C60.0381 (10)0.0375 (10)0.0450 (10)0.0005 (7)0.0124 (8)0.0077 (8)
C70.0462 (10)0.0399 (10)0.0335 (9)0.0059 (8)0.0208 (8)0.0008 (7)
C80.0380 (9)0.0308 (9)0.0360 (9)0.0012 (7)0.0234 (7)0.0045 (7)
C90.0304 (8)0.0251 (8)0.0304 (8)0.0025 (6)0.0170 (6)0.0044 (6)
O100.0343 (6)0.0260 (6)0.0382 (7)0.0022 (5)0.0170 (5)0.0013 (5)
C110.0316 (8)0.0272 (8)0.0344 (8)0.0003 (6)0.0171 (7)0.0021 (6)
C120.0304 (7)0.0243 (8)0.0253 (7)0.0010 (6)0.0170 (6)0.0016 (6)
C130.0354 (8)0.0266 (8)0.0223 (7)0.0033 (6)0.0184 (6)0.0001 (6)
C140.0325 (8)0.0284 (8)0.0241 (7)0.0040 (6)0.0204 (6)0.0037 (6)
C150.0540 (11)0.0389 (10)0.0312 (9)0.0041 (8)0.0272 (8)0.0091 (7)
C160.0553 (11)0.0421 (10)0.0386 (9)0.0027 (8)0.0375 (9)0.0024 (8)
Geometric parameters (Å, º) top
N1—N21.3465 (18)C11—C121.504 (2)
N1—C91.354 (2)C11—H11A0.9900
N1—O101.3694 (17)C11—H11B0.9900
N2—N31.304 (2)C12—C141.399 (2)
N3—C41.382 (2)C12—C131.409 (2)
C4—C51.397 (3)C13—C14i1.394 (2)
C4—C91.400 (2)C13—C151.509 (2)
C5—C61.375 (3)C14—C13i1.394 (2)
C5—H50.9500C14—C161.5129 (19)
C6—C71.410 (3)C15—H15A0.9800
C6—H60.9500C15—H15B0.9800
C7—C81.370 (3)C15—H15C0.9800
C7—H70.9500C16—H16A0.9800
C8—C91.401 (2)C16—H16B0.9800
C8—H80.9500C16—H16C0.9800
O10—C111.4707 (19)
N2—N1—C9112.41 (14)C12—C11—H11A110.5
N2—N1—O10120.24 (13)O10—C11—H11B110.5
C9—N1—O10127.34 (13)C12—C11—H11B110.5
N3—N2—N1107.67 (14)H11A—C11—H11B108.7
N2—N3—C4108.54 (14)C14—C12—C13120.49 (15)
N3—C4—C5131.05 (16)C14—C12—C11119.57 (14)
N3—C4—C9108.58 (15)C13—C12—C11119.94 (14)
C5—C4—C9120.37 (16)C14i—C13—C12119.49 (14)
C6—C5—C4117.17 (16)C14i—C13—C15119.67 (14)
C6—C5—H5121.4C12—C13—C15120.84 (15)
C4—C5—H5121.4C13i—C14—C12119.98 (13)
C5—C6—C7121.79 (17)C13i—C14—C16119.62 (14)
C5—C6—H6119.1C12—C14—C16120.38 (15)
C7—C6—H6119.1C13—C15—H15A109.5
C8—C7—C6122.08 (16)C13—C15—H15B109.5
C8—C7—H7119.0H15A—C15—H15B109.5
C6—C7—H7119.0C13—C15—H15C109.5
C7—C8—C9115.90 (15)H15A—C15—H15C109.5
C7—C8—H8122.1H15B—C15—H15C109.5
C9—C8—H8122.1C14—C16—H16A109.5
N1—C9—C4102.80 (14)C14—C16—H16B109.5
N1—C9—C8134.53 (15)H16A—C16—H16B109.5
C4—C9—C8122.67 (16)C14—C16—H16C109.5
N1—O10—C11110.19 (11)H16A—C16—H16C109.5
O10—C11—C12106.29 (12)H16B—C16—H16C109.5
O10—C11—H11A110.5
C9—N1—N2—N30.3 (2)C5—C4—C9—C80.7 (3)
O10—N1—N2—N3179.78 (14)C7—C8—C9—N1178.85 (17)
N1—N2—N3—C40.5 (2)C7—C8—C9—C41.9 (2)
N2—N3—C4—C5179.59 (18)N2—N1—O10—C1192.95 (16)
N2—N3—C4—C90.5 (2)C9—N1—O10—C1186.90 (18)
N3—C4—C5—C6179.40 (18)N1—O10—C11—C12176.52 (11)
C9—C4—C5—C60.7 (3)O10—C11—C12—C1488.45 (17)
C4—C5—C6—C70.9 (3)O10—C11—C12—C1391.90 (16)
C5—C6—C7—C80.3 (3)C14—C12—C13—C14i2.3 (3)
C6—C7—C8—C91.6 (3)C11—C12—C13—C14i177.30 (13)
N2—N1—C9—C40.03 (18)C14—C12—C13—C15177.14 (15)
O10—N1—C9—C4179.88 (14)C11—C12—C13—C153.2 (2)
N2—N1—C9—C8179.42 (18)C13—C12—C14—C13i2.4 (3)
O10—N1—C9—C80.7 (3)C11—C12—C14—C13i177.29 (13)
N3—C4—C9—N10.29 (18)C13—C12—C14—C16176.44 (15)
C5—C4—C9—N1179.80 (15)C11—C12—C14—C163.9 (2)
N3—C4—C9—C8179.20 (15)
Symmetry code: (i) x+1, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6···Cg2ii0.952.823.700 (2)154
Symmetry code: (ii) x, y1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC24H24N6O2
Mr428.49
Crystal system, space groupMonoclinic, P21/c
Temperature (K)193
a, b, c (Å)9.3895 (6), 7.5960 (2), 15.7471 (13)
β (°) 110.770 (3)
V3)1050.13 (11)
Z2
Radiation typeCu Kα
µ (mm1)0.73
Crystal size (mm)0.51 × 0.26 × 0.19
Data collection
DiffractometerEnraf–Nonius CAD-4
diffractometer
Absorption correctionψ scan
(CORINC; Draeger & Gattow, 1971)
Tmin, Tmax0.707, 0.873
No. of measured, independent and
observed [I > 2σ(I)] reflections
2075, 1996, 1905
Rint0.026
(sin θ/λ)max1)0.609
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.052, 0.147, 1.10
No. of reflections1996
No. of parameters147
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.32, 0.33

Computer programs: CAD-4 EXPRESS (Enraf–Nonius, 1994), CORINC (Draeger & Gattow, 1971), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6···Cg2i0.952.823.700 (2)154
Symmetry code: (i) x, y1/2, z+1/2.
 

References

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