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

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ISSN: 2056-9890

3-[(2E)-2-(Butan-2-yl­­idene)hydrazin­yl]-6-chloro­pyridazine

aDepartment of Chemistry, Islamia University, Bahawalpur, Pakistan, bApplied Chemistry Research Center, PCSIR Laboratories Complex, Lahore 54600, Pakistan, cUniversity of Sargodha, Department of Physics, Sargodha, Pakistan, and dInstitute of Chemistry, University of the Punjab, Lahore, Pakistan
*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 26 August 2010; accepted 31 August 2010; online 4 September 2010)

The asymmetric unit of the title compound, C8H11ClN4, contains two independent mol­ecules (A and B) with slightly different conformations: the dihedral angles between the 3-chloro-6-hydrazinylpyridazine units and butyl side chains are 4.5 (2) and 11.98 (16)°. In the crystal, the A and B mol­ecules are linked by a pair of N—H⋯N hydogen bonds, generating an R22(8) loop.

Related literature

For related structures, see: Ather et al. (2009[Ather, A. Q., Tahir, M. N., Khan, M. A. & Athar, M. M. (2009). Acta Cryst. E65, o1628.], 2010[Ather, A. Q., Tahir, M. N., Khan, M. A. & Athar, M. M. (2010). Acta Cryst. E66, o2441.]). For graph-set notation, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C8H11ClN4

  • Mr = 198.66

  • Triclinic, [P \overline 1]

  • a = 8.0623 (4) Å

  • b = 11.6768 (5) Å

  • c = 12.1314 (5) Å

  • α = 113.858 (1)°

  • β = 91.370 (2)°

  • γ = 104.880 (2)°

  • V = 998.85 (8) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.34 mm−1

  • T = 296 K

  • 0.25 × 0.15 × 0.14 mm

Data collection
  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.982, Tmax = 0.988

  • 14983 measured reflections

  • 3585 independent reflections

  • 2652 reflections with I > 2σ(I)

  • Rint = 0.031

Refinement
  • R[F2 > 2σ(F2)] = 0.035

  • wR(F2) = 0.099

  • S = 1.05

  • 3585 reflections

  • 239 parameters

  • H-atom parameters constrained

  • Δρmax = 0.15 e Å−3

  • Δρmin = −0.20 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N3—H3A⋯N6i 0.86 2.30 3.0674 (15) 148
N7—H7⋯N2i 0.86 2.24 3.0689 (15) 161
Symmetry code: (i) -x+1, -y+1, -z.

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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: ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and PLATON.

Supporting information


Comment top

In continuation of our studies of pyrazolylpyridazine derivatives (Ather et al., 2009, 2010), the title compound (I, Fig. 1) is being reported here.

The title compound (I), consists of two independent molecules. In one molecule, the 3-chloro-6-hydrazinylpyridazine moiety A (C1—C4/N1—N4/CL1) and the butane group B (C5—C8) is planar with r. m. s. deviation of 0.0217 and 0.0130 Å. The dihedral angle between A/B is 4.53 (24)°. In second molecule, the 3-chloro-6-hydrazinylpyridazine moiety C (C9—C12/N5—N8/CL2) and the butane group D (C13—C16) is planar with r. m. s. deviation of 0.0453 and 0.0446 Å. The dihedral angle between C/D is 11.98 (16)°. The title compound consists of dimers due to N—H···N type of H-bonding (Table 1, Fig. 2) with R22(8) ring motif (Bernstein et al., 1995).

Related literature top

For related structures, see: Ather et al. (2009, 2010). For graph-set notation, see: Bernstein et al. (1995).

Experimental top

3-Chloro-6-hydrazinylpyridazine (0.5 g, 3.46 mmol), dissolved in ethyl-methylketone was refluxed for 30 min. The unreacted ethyl-methylketone was distilled off yielding the crude material. The product was re-crystallized in alcohol to affoard colorless needles of (I).

Refinement top

The H-atoms were positioned geometrically (N–H = 0.86, C–H = 0.93–0.97 Å) and were included in the refinement in the riding model approximation, with Uiso(H) = xUeq(C, N), where x = 1.5 for methyl and x = 1.2 for all other H-atoms.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. Two independent molecules of (I) with 50% probability displacement ellipsoids. Dashed lines denote intermolecular hydrogen bonds, forming a dimer: the N6 moleucle shown is generated by the symmetry operation (1–x, 1–y, –z) from the asymmetric atoms.
3-[(2E)-2-(Butan-2-ylidene)hydrazinyl]-6-chloropyridazine top
Crystal data top
C8H11ClN4Z = 4
Mr = 198.66F(000) = 416
Triclinic, P1Dx = 1.321 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 8.0623 (4) ÅCell parameters from 2652 reflections
b = 11.6768 (5) Åθ = 2.1–25.3°
c = 12.1314 (5) ŵ = 0.34 mm1
α = 113.858 (1)°T = 296 K
β = 91.370 (2)°Needle, colorless
γ = 104.880 (2)°0.25 × 0.15 × 0.14 mm
V = 998.85 (8) Å3
Data collection top
Bruker Kappa APEXII CCD
diffractometer
3585 independent reflections
Radiation source: fine-focus sealed tube2652 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.031
Detector resolution: 8.10 pixels mm-1θmax = 25.3°, θmin = 2.1°
ω scansh = 99
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
k = 1313
Tmin = 0.982, Tmax = 0.988l = 1411
14983 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)] = 0.035Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.099H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0426P)2 + 0.1867P]
where P = (Fo2 + 2Fc2)/3
3585 reflections(Δ/σ)max = 0.001
239 parametersΔρmax = 0.15 e Å3
0 restraintsΔρmin = 0.20 e Å3
Crystal data top
C8H11ClN4γ = 104.880 (2)°
Mr = 198.66V = 998.85 (8) Å3
Triclinic, P1Z = 4
a = 8.0623 (4) ÅMo Kα radiation
b = 11.6768 (5) ŵ = 0.34 mm1
c = 12.1314 (5) ÅT = 296 K
α = 113.858 (1)°0.25 × 0.15 × 0.14 mm
β = 91.370 (2)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer
3585 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
2652 reflections with I > 2σ(I)
Tmin = 0.982, Tmax = 0.988Rint = 0.031
14983 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0350 restraints
wR(F2) = 0.099H-atom parameters constrained
S = 1.05Δρmax = 0.15 e Å3
3585 reflectionsΔρmin = 0.20 e Å3
239 parameters
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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
Cl10.56878 (7)1.01144 (5)0.14461 (4)0.0711 (2)
N10.65078 (7)0.81818 (4)0.01826 (4)0.0494 (5)
N20.69138 (9)0.70411 (6)0.06328 (4)0.0477 (5)
N30.73568 (11)0.52631 (8)0.04789 (4)0.0485 (5)
N40.75811 (18)0.46292 (14)0.02371 (12)0.0446 (5)
C10.6218 (2)0.86549 (17)0.09480 (15)0.0457 (6)
C20.6309 (2)0.80724 (18)0.17388 (15)0.0482 (6)
C30.6692 (2)0.69257 (17)0.12939 (14)0.0456 (6)
C40.6972 (2)0.64155 (16)0.00695 (14)0.0403 (6)
C50.8018 (2)0.35764 (18)0.02463 (16)0.0446 (6)
C60.8294 (3)0.29374 (19)0.05683 (17)0.0546 (7)
C70.8037 (3)0.3631 (2)0.18693 (18)0.0706 (9)
C80.8324 (3)0.29472 (19)0.15401 (16)0.0571 (7)
Cl20.61890 (8)0.92216 (5)0.55956 (5)0.0741 (2)
N50.4684 (2)0.70148 (16)0.37821 (14)0.0577 (6)
N60.3743 (2)0.57428 (16)0.32230 (13)0.0577 (6)
N70.2290 (2)0.38112 (15)0.32596 (13)0.0557 (6)
N80.1391 (2)0.31693 (16)0.38987 (13)0.0527 (6)
C90.4960 (2)0.75931 (18)0.49629 (16)0.0499 (6)
C100.4326 (3)0.69965 (19)0.57130 (16)0.0572 (7)
C110.3386 (3)0.57264 (19)0.51703 (16)0.0560 (7)
C120.3135 (2)0.51037 (18)0.38917 (15)0.0461 (6)
C130.0646 (3)0.19453 (19)0.33475 (16)0.0514 (7)
C140.0380 (3)0.1305 (2)0.40720 (18)0.0656 (8)
C150.0180 (3)0.2152 (2)0.5419 (2)0.0842 (10)
C160.06718 (9)0.10973 (7)0.20380 (5)0.0690 (8)
H20.611450.845920.254150.0578*
H30.676760.648810.177700.0547*
H3A0.745690.494090.124050.0582*
H6A0.750510.205660.022870.0655*
H6B0.946550.286380.055980.0655*
H7A0.885830.448650.223470.1059*
H7B0.688090.370980.189420.1059*
H7C0.820740.313820.231040.1059*
H8A0.729870.275830.207800.0858*
H8B0.927510.353140.168690.0858*
H8C0.859360.214850.168450.0858*
H70.231450.340800.249230.0668*
H100.454000.745530.655670.0687*
H110.292140.527780.562650.0673*
H14A0.003690.053160.396090.0787*
H14B0.159740.101620.374040.0787*
H15A0.100430.238870.577310.1264*
H15B0.092070.167760.579580.1264*
H15C0.049570.293000.554420.1264*
H16A0.000220.131120.152650.1035*
H16B0.018800.019440.187900.1035*
H16C0.184590.124280.186930.1035*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.1018 (5)0.0565 (3)0.0605 (3)0.0378 (3)0.0197 (3)0.0210 (3)
N10.0617 (10)0.0490 (9)0.0437 (8)0.0192 (8)0.0131 (7)0.0235 (7)
N20.0627 (10)0.0477 (9)0.0393 (8)0.0201 (8)0.0144 (7)0.0222 (7)
N30.0670 (10)0.0479 (9)0.0362 (7)0.0190 (8)0.0112 (7)0.0219 (7)
N40.0485 (9)0.0478 (9)0.0427 (8)0.0109 (7)0.0063 (7)0.0261 (7)
C10.0480 (11)0.0428 (10)0.0437 (10)0.0106 (8)0.0075 (8)0.0173 (8)
C20.0534 (11)0.0505 (11)0.0360 (9)0.0100 (9)0.0095 (8)0.0167 (8)
C30.0521 (11)0.0494 (11)0.0367 (9)0.0091 (9)0.0078 (8)0.0230 (8)
C40.0404 (10)0.0420 (10)0.0373 (9)0.0066 (8)0.0055 (7)0.0188 (8)
C50.0414 (10)0.0454 (11)0.0467 (10)0.0070 (8)0.0060 (8)0.0228 (9)
C60.0529 (12)0.0582 (12)0.0621 (12)0.0144 (10)0.0074 (9)0.0358 (10)
C70.0867 (16)0.0831 (16)0.0590 (12)0.0271 (13)0.0127 (11)0.0454 (12)
C80.0663 (13)0.0581 (12)0.0506 (11)0.0227 (10)0.0131 (9)0.0236 (10)
Cl20.0911 (4)0.0514 (3)0.0707 (4)0.0066 (3)0.0057 (3)0.0259 (3)
N50.0740 (12)0.0536 (10)0.0461 (9)0.0099 (9)0.0093 (8)0.0269 (8)
N60.0790 (12)0.0537 (10)0.0401 (8)0.0104 (9)0.0088 (8)0.0249 (8)
N70.0760 (11)0.0497 (10)0.0379 (8)0.0079 (8)0.0112 (8)0.0213 (7)
N80.0610 (10)0.0546 (10)0.0466 (9)0.0123 (8)0.0115 (7)0.0282 (8)
C90.0580 (12)0.0459 (11)0.0482 (10)0.0162 (9)0.0093 (9)0.0215 (9)
C100.0795 (14)0.0535 (13)0.0373 (10)0.0183 (11)0.0123 (9)0.0185 (9)
C110.0786 (14)0.0534 (12)0.0409 (10)0.0169 (11)0.0182 (9)0.0256 (9)
C120.0540 (11)0.0488 (11)0.0394 (9)0.0147 (9)0.0086 (8)0.0225 (9)
C130.0534 (12)0.0540 (12)0.0493 (10)0.0128 (10)0.0069 (9)0.0261 (10)
C140.0692 (14)0.0642 (14)0.0642 (13)0.0077 (11)0.0132 (10)0.0349 (11)
C150.1004 (19)0.0848 (18)0.0671 (15)0.0104 (14)0.0291 (13)0.0410 (13)
C160.0818 (16)0.0572 (13)0.0572 (12)0.0078 (11)0.0125 (11)0.0212 (10)
Geometric parameters (Å, º) top
Cl1—C11.734 (2)C6—H6B0.9700
Cl2—C91.733 (2)C6—H6A0.9700
N1—N21.3504 (9)C7—H7A0.9600
N1—C11.3075 (17)C7—H7C0.9600
N2—C41.3345 (19)C7—H7B0.9600
N3—N41.3843 (18)C8—H8A0.9600
N3—C41.360 (2)C8—H8C0.9600
N4—C51.276 (3)C8—H8B0.9600
N3—H3A0.8600C9—C101.388 (3)
N5—C91.297 (2)C10—C111.348 (3)
N5—N61.350 (3)C11—C121.405 (2)
N6—C121.333 (3)C13—C161.4981 (19)
N7—N81.381 (2)C13—C141.505 (3)
N7—C121.357 (3)C14—C151.508 (3)
N8—C131.272 (3)C10—H100.9300
N7—H70.8600C11—H110.9300
C1—C21.392 (3)C14—H14A0.9700
C2—C31.347 (3)C14—H14B0.9700
C3—C41.408 (2)C15—H15A0.9600
C5—C81.498 (3)C15—H15B0.9600
C5—C61.501 (3)C15—H15C0.9600
C6—C71.503 (3)C16—H16A0.9600
C2—H20.9300C16—H16B0.9600
C3—H30.9300C16—H16C0.9600
N2—N1—C1118.43 (10)H8A—C8—H8C109.00
N1—N2—C4119.67 (8)C5—C8—H8A109.00
N4—N3—C4117.38 (10)H8B—C8—H8C109.00
N3—N4—C5118.39 (13)H8A—C8—H8B109.00
C4—N3—H3A121.00C5—C8—H8C109.00
N4—N3—H3A121.00C5—C8—H8B109.00
N6—N5—C9119.09 (18)Cl2—C9—C10119.98 (14)
N5—N6—C12119.53 (15)Cl2—C9—N5115.69 (16)
N8—N7—C12117.28 (14)N5—C9—C10124.3 (2)
N7—N8—C13119.01 (15)C9—C10—C11117.37 (17)
N8—N7—H7121.00C10—C11—C12117.67 (19)
C12—N7—H7121.00N7—C12—C11122.28 (19)
N1—C1—C2124.75 (16)N6—C12—N7115.75 (15)
Cl1—C1—C2119.92 (13)N6—C12—C11121.96 (19)
Cl1—C1—N1115.33 (13)N8—C13—C14116.84 (17)
C1—C2—C3117.28 (16)N8—C13—C16125.68 (18)
C2—C3—C4117.42 (17)C14—C13—C16117.47 (17)
N2—C4—N3114.99 (12)C13—C14—C15115.48 (19)
N3—C4—C3122.59 (16)C9—C10—H10121.00
N2—C4—C3122.41 (16)C11—C10—H10121.00
C6—C5—C8117.44 (18)C10—C11—H11121.00
N4—C5—C8125.76 (19)C12—C11—H11121.00
N4—C5—C6116.78 (16)C13—C14—H14A108.00
C5—C6—C7115.54 (19)C13—C14—H14B108.00
C3—C2—H2121.00C15—C14—H14A108.00
C1—C2—H2121.00C15—C14—H14B108.00
C4—C3—H3121.00H14A—C14—H14B107.00
C2—C3—H3121.00C14—C15—H15A109.00
C5—C6—H6A108.00C14—C15—H15B109.00
C7—C6—H6B108.00C14—C15—H15C109.00
C5—C6—H6B108.00H15A—C15—H15B110.00
H6A—C6—H6B107.00H15A—C15—H15C109.00
C7—C6—H6A108.00H15B—C15—H15C110.00
H7A—C7—H7B110.00C13—C16—H16A109.00
H7A—C7—H7C109.00C13—C16—H16B109.00
C6—C7—H7C109.00C13—C16—H16C109.00
H7B—C7—H7C109.00H16A—C16—H16B109.00
C6—C7—H7B109.00H16A—C16—H16C109.00
C6—C7—H7A109.00H16B—C16—H16C109.00
C1—N1—N2—C41.45 (15)N8—N7—C12—C1112.0 (3)
N2—N1—C1—Cl1179.47 (8)N7—N8—C13—C161.2 (3)
N2—N1—C1—C20.5 (2)N7—N8—C13—C14177.43 (18)
N1—N2—C4—N3178.67 (10)N1—C1—C2—C31.3 (3)
N1—N2—C4—C32.6 (2)Cl1—C1—C2—C3178.68 (14)
C4—N3—N4—C5176.95 (15)C1—C2—C3—C40.2 (3)
N4—N3—C4—N2174.58 (12)C2—C3—C4—N21.8 (3)
N4—N3—C4—C34.1 (2)C2—C3—C4—N3179.62 (16)
N3—N4—C5—C6178.44 (15)N4—C5—C6—C70.6 (3)
N3—N4—C5—C80.2 (3)C8—C5—C6—C7177.78 (19)
C9—N5—N6—C120.8 (3)Cl2—C9—C10—C11179.66 (18)
N6—N5—C9—Cl2179.70 (14)N5—C9—C10—C111.1 (3)
N6—N5—C9—C101.0 (3)C9—C10—C11—C120.6 (3)
N5—N6—C12—N7176.31 (16)C10—C11—C12—N62.3 (3)
N5—N6—C12—C112.5 (3)C10—C11—C12—N7176.4 (2)
C12—N7—N8—C13176.99 (19)N8—C13—C14—C158.9 (3)
N8—N7—C12—N6169.24 (16)C16—C13—C14—C15172.35 (18)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3A···N6i0.862.303.0674 (15)148
N7—H7···N2i0.862.243.0689 (15)161
Symmetry code: (i) x+1, y+1, z.

Experimental details

Crystal data
Chemical formulaC8H11ClN4
Mr198.66
Crystal system, space groupTriclinic, P1
Temperature (K)296
a, b, c (Å)8.0623 (4), 11.6768 (5), 12.1314 (5)
α, β, γ (°)113.858 (1), 91.370 (2), 104.880 (2)
V3)998.85 (8)
Z4
Radiation typeMo Kα
µ (mm1)0.34
Crystal size (mm)0.25 × 0.15 × 0.14
Data collection
DiffractometerBruker Kappa APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.982, 0.988
No. of measured, independent and
observed [I > 2σ(I)] reflections
14983, 3585, 2652
Rint0.031
(sin θ/λ)max1)0.600
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.035, 0.099, 1.05
No. of reflections3585
No. of parameters239
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.15, 0.20

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3A···N6i0.862.303.0674 (15)148
N7—H7···N2i0.862.243.0689 (15)161
Symmetry code: (i) x+1, y+1, z.
 

Acknowledgements

The authors acknowledge the provision of funds for the purchase of the diffractometer and encouragement by Dr Muhammad Akram Chaudhary, Vice Chancellor, University of Sargodha, Pakistan. They also acknowledge the technical support provided by Bana Inter­national, Karachi, Pakistan.

References

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