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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 4| April 2011| Pages o972-o973

A triclinic polymorph with Z = 3 of N,N′-bis­­(2-pyrid­yl)oxamide

aSchool of Chemical Engineering, Huanggang Normal University, 438000 Huanggang, People's Republic of China, bExperimental Center, Guiyang University, 550005 Guiyang, People's Republic of China, and cInstitute of Applied Chemistry, Guizhou University, 550025 Guiyang, People's Republic of China
*Correspondence e-mail: wangfang198107@hotmail.com

(Received 12 February 2011; accepted 18 March 2011; online 26 March 2011)

The asymmetric unit of the title compound, C12H10N4O2, contains three half-mol­ecules. Each half-mol­ecule is completed by crystallographic inversion symmetry. The title compound, (I), is a polymorph of the structure, (II), reported by Hsu & Chen [Eur. J. Inorg. Chem. (2004), 1488–1493]. In the original report, the compound crystallized in the tetra­gonal space group P[\overline{4}]21c (Z = 8), whereas the structure reported here is triclinic (P[\overline{1}], Z = 3). In both forms, each oxamide mol­ecule is almost planar (with maximum deviations are 0.266 and 0.166 Å) and the O atoms are trans oriented. The principal difference between the two forms lies in the different hydrogen-bonding patterns. In (I), two N—H⋯O and one N—H⋯N hydrogen bonds link the mol­ecules, forming a two-dimensional network, whereas in (II) there are no classical hydrogen bonds to O atoms and only weak C—H⋯O inter­actions are found along with rings of N—H⋯N bonds.

Related literature

For general background to the use of N,N′-disubstituted oxamides as ligands, see: Bencini et al. (1986[Bencini, A., Benelli, C., Fabretti, A. C., Franchini, G. & Gatteschi, D. (1986). Inorg. Chem. 25, 1063-1066.]). For the synthesis and related structure, see: Hsu & Chen (2004[Hsu, Y.-F. & Chen, J.-D. (2004). Eur. J. Inorg. Chem. pp. 1488-1493.]).

[Scheme 1]

Experimental

Crystal data
  • C12H10N4O2

  • Mr = 242.24

  • Triclinic, [P \overline 1]

  • a = 8.459 (2) Å

  • b = 10.705 (3) Å

  • c = 11.058 (3) Å

  • α = 99.555 (9)°

  • β = 101.344 (8)°

  • γ = 112.980 (8)°

  • V = 870.5 (4) Å3

  • Z = 3

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 298 K

  • 0.26 × 0.26 × 0.20 mm

Data collection
  • Bruker SMART APEX CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2003[Sheldrick, G. M. (2003). SADABS. University of Göttingen, Germany.]) Tmin = 0.975, Tmax = 0.980

  • 8909 measured reflections

  • 3018 independent reflections

  • 2575 reflections with I > 2σ(I)

  • Rint = 0.021

Refinement
  • R[F2 > 2σ(F2)] = 0.044

  • wR(F2) = 0.125

  • S = 1.07

  • 3018 reflections

  • 245 parameters

  • H-atom parameters constrained

  • Δρmax = 0.24 e Å−3

  • Δρmin = −0.34 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H2A⋯O3 0.86 2.39 3.176 (2) 153
N4—H4A⋯O3 0.86 2.27 2.898 (2) 130
N6—H6⋯N3i 0.86 2.39 3.188 (2) 155
Symmetry code: (i) -x+1, -y+1, -z+1.

Data collection: SMART (Bruker, 2002[Bruker (2002). SAINT and SMART. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2002[Bruker (2002). SAINT and SMART. 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: XP (Siemens, 1994[Siemens (1994). XP. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]) and CAMERON (Watkin et al., 1993[Watkin, D. M., Pearce, L. & Prout, C. K. (1993). CAMERON. Chemical Crystallography Laboratory, University of Oxford, England.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information


Comment top

N,N'-disubstituted oxamides are known to be versatile organic ligands since their coordinating ability toward transition-metal ions can be modified and tuned by changing the nature of the amide substituents (Bencini et al., 1986). The title compound, (I), is a triclinic polymorph of the previously reported crystal structure of this symmetrical N,N'-disubstituted oxamide which crystallizes in the tetragonal space group P-421/c (Hsu & Chen, 2004). The relative arrangement of the molecules observed in the current structure is distinctively different from that previously reported.

The molecular structure of (I) is shown in Fig. 1. It crystallizes in the space group P-1 with three molecules in each unit cell. Each N,N'-di(2-pyridyl)oxamide molecule is almost planar and the O atoms are trans-oriented. In the crystal structure, classical N—H···O and N—H···N hydrogen bonds (Table 1, Fig. 2) link the molecules to form a two-dimensional network.

Related literature top

For general background to the use of N,N'-disubstituted oxamides as ligands, see: Bencini et al. (1986). For the synthesis and related structure, see: Hsu & Chen (2004).

Experimental top

2-Aminopyridine (4.7 g, 50 mmol) was dissolved in 200 ml CH2Cl2, followed by addition of triethyl amine (10.0 ml, 72.1 mmol) at 273 K. The mixture was then stirred for 10 min. Oxalyl chloride (2.2 ml, 25 mmol) in 10 ml CH2Cl2 was then added slowly to the above mixture. After continuous stirring for about 3 h at 273 K, the resulting solution was concentrated under vacuum until a large amount of solid precipitated. The solid was filtered, washed with water and then dried in vacuum. Yield: 4.3 g (71%). Colourless block crystals suitable for X-ray crystallography were obtained by slow evaporation of the solvent from a solution of the title compound in toluene.

Refinement top

All the hydrogen atoms were placed in calculated positions, with C—H distances of 0.93 Å (aromatic) and N—H distance of 0.86 Å, and were included in the final cycles of refinement as riding, with Uiso(H) = 1.2Ueq of the carrier atom.

Computing details top

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SHELXL97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP (Siemens, 1994) and CAMERON (Watkin et al., 1993); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), with atom labels and 30% probability displacement ellipsoids for non-H atoms. [symmetry codes: (i) -x + 1, -y, -z + 1; (ii) -x, -y, -z + 1; (iii) -x + 1, -y + 1, -z + 1.]
[Figure 2] Fig. 2. The two-dimensional hydrogen-bonded structure. Dashed lines indicate hydrogen bonds. H atoms not involved in hydrogen bonding were omitted for clarity. [symmetry code: (iii) -x + 1, -y + 1, -z + 1.]
N,N'-bis(pyridin-2-yl)ethanediamide top
Crystal data top
C12H10N4O2Z = 3
Mr = 242.24F(000) = 378
Triclinic, P1Dx = 1.386 Mg m3
Hall symbol: -p 1Mo Kα radiation, λ = 0.71073 Å
a = 8.459 (2) ÅCell parameters from 2575 reflections
b = 10.705 (3) Åθ = 2.0–25.1°
c = 11.058 (3) ŵ = 0.10 mm1
α = 99.555 (9)°T = 298 K
β = 101.344 (8)°Block, colourless
γ = 112.980 (8)°0.26 × 0.26 × 0.20 mm
V = 870.5 (4) Å3
Data collection top
Bruker SMART APEX CCD
diffractometer
3018 independent reflections
Radiation source: fine-focus sealed tube2575 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.021
ϕ and ω scansθmax = 25.1°, θmin = 2.0°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
h = 109
Tmin = 0.975, Tmax = 0.980k = 1212
8909 measured reflectionsl = 1313
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)] = 0.044Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.125H-atom parameters constrained
S = 1.07 w = 1/[σ2(Fo2) + (0.0745P)2 + 0.1649P]
where P = (Fo2 + 2Fc2)/3
3018 reflections(Δ/σ)max < 0.001
245 parametersΔρmax = 0.24 e Å3
0 restraintsΔρmin = 0.34 e Å3
Crystal data top
C12H10N4O2γ = 112.980 (8)°
Mr = 242.24V = 870.5 (4) Å3
Triclinic, P1Z = 3
a = 8.459 (2) ÅMo Kα radiation
b = 10.705 (3) ŵ = 0.10 mm1
c = 11.058 (3) ÅT = 298 K
α = 99.555 (9)°0.26 × 0.26 × 0.20 mm
β = 101.344 (8)°
Data collection top
Bruker SMART APEX CCD
diffractometer
3018 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
2575 reflections with I > 2σ(I)
Tmin = 0.975, Tmax = 0.980Rint = 0.021
8909 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0440 restraints
wR(F2) = 0.125H-atom parameters constrained
S = 1.07Δρmax = 0.24 e Å3
3018 reflectionsΔρmin = 0.34 e Å3
245 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
C10.8362 (2)0.46853 (19)0.37248 (18)0.0520 (4)
H10.84990.56080.39080.062*
C20.9305 (2)0.4331 (2)0.29625 (17)0.0530 (5)
H21.00850.50020.26550.064*
C30.9066 (3)0.2958 (2)0.26675 (17)0.0557 (5)
H30.96720.26820.21440.067*
C40.7921 (3)0.1992 (2)0.31520 (17)0.0525 (4)
H40.77320.10560.29570.063*
C50.7062 (2)0.24577 (17)0.39383 (15)0.0413 (4)
C60.5610 (2)0.02730 (17)0.45799 (16)0.0433 (4)
C70.2643 (3)0.1234 (2)0.11856 (19)0.0686 (6)
H70.31330.20170.08810.082*
C80.2515 (4)0.0019 (2)0.0534 (2)0.0805 (7)
H80.29110.00870.01910.097*
C90.1791 (4)0.1164 (2)0.0977 (2)0.0880 (8)
H90.16810.20330.05520.106*
C100.1222 (3)0.1038 (2)0.20524 (19)0.0662 (6)
H100.07310.18090.23710.079*
C110.1405 (2)0.02693 (16)0.26431 (14)0.0386 (4)
C120.0128 (2)0.03698 (15)0.43944 (14)0.0364 (3)
C130.7504 (3)0.5115 (2)0.97931 (17)0.0646 (6)
H130.84790.56921.05040.078*
C140.6308 (3)0.3874 (2)0.99039 (17)0.0631 (5)
H140.64600.36121.06640.076*
C150.4884 (3)0.3032 (2)0.88626 (18)0.0660 (6)
H150.40420.21750.89010.079*
C160.4690 (3)0.34467 (18)0.77573 (16)0.0521 (5)
H160.37190.28860.70400.063*
C170.5974 (2)0.47196 (15)0.77397 (13)0.0347 (3)
C180.48440 (19)0.45519 (14)0.54712 (13)0.0312 (3)
N10.72567 (19)0.37762 (14)0.42180 (14)0.0472 (4)
N20.59256 (19)0.15935 (14)0.45411 (14)0.0457 (4)
H2A0.53620.19590.49340.055*
N30.2108 (2)0.14008 (15)0.22304 (13)0.0505 (4)
N40.08990 (17)0.05422 (13)0.37520 (12)0.0385 (3)
H4A0.11090.14020.40600.046*
N50.7374 (2)0.55612 (16)0.87343 (13)0.0531 (4)
N60.59098 (16)0.52565 (12)0.66636 (11)0.0351 (3)
H60.66280.61270.67840.042*
O10.62022 (18)0.04585 (13)0.40434 (13)0.0584 (4)
O20.03443 (16)0.16334 (11)0.41046 (11)0.0501 (3)
O30.37249 (15)0.33253 (10)0.51223 (9)0.0415 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0499 (10)0.0450 (10)0.0644 (11)0.0197 (8)0.0202 (9)0.0213 (8)
C20.0461 (10)0.0640 (12)0.0538 (10)0.0229 (9)0.0177 (8)0.0273 (9)
C30.0585 (11)0.0729 (13)0.0507 (10)0.0377 (10)0.0235 (9)0.0228 (9)
C40.0628 (11)0.0524 (10)0.0545 (10)0.0336 (9)0.0223 (9)0.0177 (8)
C50.0377 (8)0.0414 (9)0.0461 (9)0.0190 (7)0.0099 (7)0.0139 (7)
C60.0408 (9)0.0362 (8)0.0523 (9)0.0183 (7)0.0095 (7)0.0116 (7)
C70.1028 (17)0.0534 (11)0.0552 (11)0.0248 (11)0.0486 (12)0.0216 (9)
C80.123 (2)0.0638 (13)0.0675 (13)0.0354 (13)0.0651 (14)0.0193 (11)
C90.144 (2)0.0524 (12)0.0840 (16)0.0407 (14)0.0736 (17)0.0163 (11)
C100.1025 (16)0.0397 (9)0.0627 (12)0.0248 (10)0.0487 (12)0.0162 (9)
C110.0413 (8)0.0363 (8)0.0350 (8)0.0117 (7)0.0144 (6)0.0106 (6)
C120.0348 (8)0.0306 (8)0.0382 (8)0.0075 (6)0.0119 (6)0.0110 (6)
C130.0660 (12)0.0720 (13)0.0381 (9)0.0167 (10)0.0012 (8)0.0205 (9)
C140.0823 (14)0.0694 (13)0.0403 (10)0.0300 (11)0.0168 (9)0.0304 (9)
C150.0864 (15)0.0509 (11)0.0469 (11)0.0109 (10)0.0205 (10)0.0253 (9)
C160.0639 (11)0.0433 (9)0.0350 (8)0.0078 (8)0.0133 (8)0.0149 (7)
C170.0420 (8)0.0353 (8)0.0308 (7)0.0176 (7)0.0145 (6)0.0123 (6)
C180.0351 (7)0.0296 (7)0.0309 (7)0.0125 (6)0.0151 (6)0.0104 (6)
N10.0447 (8)0.0396 (8)0.0619 (9)0.0187 (6)0.0209 (7)0.0175 (7)
N20.0473 (8)0.0368 (7)0.0613 (9)0.0224 (6)0.0219 (7)0.0164 (6)
N30.0719 (10)0.0409 (8)0.0412 (7)0.0186 (7)0.0299 (7)0.0159 (6)
N40.0484 (8)0.0292 (6)0.0365 (7)0.0121 (6)0.0186 (6)0.0102 (5)
N50.0540 (9)0.0531 (9)0.0366 (7)0.0098 (7)0.0052 (6)0.0164 (6)
N60.0408 (7)0.0291 (6)0.0311 (6)0.0088 (5)0.0122 (5)0.0112 (5)
O10.0672 (8)0.0431 (7)0.0791 (9)0.0310 (6)0.0337 (7)0.0199 (6)
O20.0628 (8)0.0309 (6)0.0526 (7)0.0104 (5)0.0290 (6)0.0117 (5)
O30.0489 (6)0.0306 (6)0.0343 (6)0.0053 (5)0.0129 (5)0.0108 (4)
Geometric parameters (Å, º) top
C1—N11.336 (2)C11—N31.326 (2)
C1—C21.373 (3)C11—N41.399 (2)
C1—H10.9300C12—O21.2149 (18)
C2—C31.375 (3)C12—N41.3411 (18)
C2—H20.9300C12—C12ii1.537 (3)
C3—C41.378 (3)C13—N51.337 (2)
C3—H30.9300C13—C141.363 (3)
C4—C51.386 (2)C13—H130.9300
C4—H40.9300C14—C151.361 (3)
C5—N11.330 (2)C14—H140.9300
C5—N21.410 (2)C15—C161.370 (2)
C6—O11.219 (2)C15—H150.9300
C6—N21.342 (2)C16—C171.378 (2)
C6—C6i1.535 (3)C16—H160.9300
C7—N31.331 (2)C17—N51.323 (2)
C7—C81.365 (3)C17—N61.4054 (18)
C7—H70.9300C18—O31.2193 (18)
C8—C91.360 (3)C18—N61.3384 (19)
C8—H80.9300C18—C18iii1.523 (3)
C9—C101.374 (3)N2—H2A0.8600
C9—H90.9300N4—H4A0.8600
C10—C111.377 (2)N6—H60.8600
C10—H100.9300
N1—C1—C2123.58 (17)O2—C12—N4126.93 (14)
N1—C1—H1118.2O2—C12—C12ii121.30 (15)
C2—C1—H1118.2N4—C12—C12ii111.77 (15)
C1—C2—C3118.10 (17)N5—C13—C14124.56 (18)
C1—C2—H2121.0N5—C13—H13117.7
C3—C2—H2121.0C14—C13—H13117.7
C2—C3—C4119.68 (17)C15—C14—C13117.60 (16)
C2—C3—H3120.2C15—C14—H14121.2
C4—C3—H3120.2C13—C14—H14121.2
C3—C4—C5117.98 (17)C14—C15—C16119.96 (17)
C3—C4—H4121.0C14—C15—H15120.0
C5—C4—H4121.0C16—C15—H15120.0
N1—C5—C4123.16 (15)C15—C16—C17118.07 (17)
N1—C5—N2113.25 (14)C15—C16—H16121.0
C4—C5—N2123.58 (15)C17—C16—H16121.0
O1—C6—N2126.53 (16)N5—C17—C16123.44 (14)
O1—C6—C6i120.90 (18)N5—C17—N6113.46 (13)
N2—C6—C6i112.56 (18)C16—C17—N6123.09 (14)
N3—C7—C8123.90 (18)O3—C18—N6126.12 (12)
N3—C7—H7118.1O3—C18—C18iii121.04 (16)
C8—C7—H7118.1N6—C18—C18iii112.84 (15)
C9—C8—C7117.97 (19)C5—N1—C1117.47 (15)
C9—C8—H8121.0C6—N2—C5128.27 (15)
C7—C8—H8121.0C6—N2—H2A115.9
C8—C9—C10120.0 (2)C5—N2—H2A115.9
C8—C9—H9120.0C11—N3—C7117.05 (15)
C10—C9—H9120.0C12—N4—C11128.10 (13)
C9—C10—C11117.76 (17)C12—N4—H4A115.9
C9—C10—H10121.1C11—N4—H4A115.9
C11—C10—H10121.1C17—N5—C13116.37 (15)
N3—C11—C10123.32 (15)C18—N6—C17126.63 (12)
N3—C11—N4113.26 (14)C18—N6—H6116.7
C10—C11—N4123.41 (14)C17—N6—H6116.7
Symmetry codes: (i) x+1, y, z+1; (ii) x, y, z+1; (iii) x+1, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2A···O30.862.393.176 (2)153
N4—H4A···O30.862.272.898 (2)130
N6—H6···N3iii0.862.393.188 (2)155
Symmetry code: (iii) x+1, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC12H10N4O2
Mr242.24
Crystal system, space groupTriclinic, P1
Temperature (K)298
a, b, c (Å)8.459 (2), 10.705 (3), 11.058 (3)
α, β, γ (°)99.555 (9), 101.344 (8), 112.980 (8)
V3)870.5 (4)
Z3
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.26 × 0.26 × 0.20
Data collection
DiffractometerBruker SMART APEX CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2003)
Tmin, Tmax0.975, 0.980
No. of measured, independent and
observed [I > 2σ(I)] reflections
8909, 3018, 2575
Rint0.021
(sin θ/λ)max1)0.596
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.044, 0.125, 1.07
No. of reflections3018
No. of parameters245
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.24, 0.34

Computer programs: SMART (Bruker, 2002), SAINT (Bruker, 2002), SHELXL97 (Sheldrick, 2008), XP (Siemens, 1994) and CAMERON (Watkin et al., 1993), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2A···O30.862.393.176 (2)153
N4—H4A···O30.862.272.898 (2)130
N6—H6···N3i0.862.393.188 (2)155
Symmetry code: (i) x+1, y+1, z+1.
 

Acknowledgements

The authors thank the Doctoral Foundation of Huanggang Normal University (No. 09CD157) for financial support.

References

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ISSN: 2056-9890
Volume 67| Part 4| April 2011| Pages o972-o973
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