The title compound, C
10H
10N
2·C
4H
8N
2O
2, consists of hydrogen-bonded 2,3-dimethylquinoxaline and dimethylglyoxime molecules. Both dimethylglyoximes are located on an inversion centre and there are two half-molecules in the asymmetric unit. The dimethylglyoxime molecules are linked about inversion centres to the 2,3-dimethylquinoxaline moiety by O—H
N hydrogen bonds (O
N 2.898 and 2.805 Å) to form polymeric chains.
Supporting information
CCDC reference: 170882
Key indicators
- Single-crystal X-ray study
- T = 294 K
- Mean (C-C) = 0.002 Å
- R factor = 0.046
- wR factor = 0.133
- Data-to-parameter ratio = 14.9
checkCIF results
No syntax errors found
ADDSYM reports no extra symmetry
Alert Level A:
PLAT_726 Alert A H...A Calc 13.00(2), Rep 2.04510, Dev. 10.95 Ang.
H1 -N2 1.555 1.546
PLAT_727 Alert A D...A Calc 12.230(3), Rep 2.89770, Dev. 9.33 Ang.
O1 -N2 1.555 1.546
PLAT_728 Alert A D-H..A Calc 24.9(16), Rep 176.30, Dev. 151.40 Deg.
O1 -H1 -N2 1.555 1.555 1.546
Alert Level C:
PLAT_745 Alert C D-H Calc 0.85(2), Rep 0.85390 .... Missing s.u.
O1 -H1 1.555 1.555
PLAT_745 Alert C D-H Calc 0.81(2), Rep 0.81800 .... Missing s.u.
O2 -H2 1.555 1.555
PLAT_746 Alert C H...A Calc 2.00(2), Rep 1.99170 .... Missing s.u.
H2 -N3 1.555 1.555
PLAT_747 Alert C D...A Calc 2.805(2), Rep 2.80530 .... Missing s.u.
O2 -N3 1.555 1.555
PLAT_748 Alert C D-H..A Calc 173(2), Rep 172.85 .... Missing s.u.
O2 -H2 -N3 1.555 1.555 1.555
3 Alert Level A = Potentially serious problem
0 Alert Level B = Potential problem
5 Alert Level C = Please check
The title compound, (I), was prepared from a mixture of 2,3-butaneidone monoxime
(2.02 g, 20.0 mmol), o-phenylendiamine (1.08 g, 10.0 mmol) and
Na2SO4 (2.84 g, 20.0 mmol) in ethanol (30 ml). The mixture was heated at
343 K for 6 h. The solution was filtered and allowed to stand overnight in a
refrigerator. The resulting precipitate was filtered and then recrystallized
from 1,4-dioxane.
The oxime H atoms were located from a difference map and refined isotropically;
the positions of the remaining H atoms were calculated geometrically at
distances of 0.93 (CH) and 0.96 Å (CH3) from the corresponding C atoms,
and a riding model was used during the refinement process. The H atoms of the
C2 and C13 methyl groups are disordered.
Data collection: MolEN (Fair, 1990); cell refinement: MolEN; data reduction: MolEN; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: MolEN.
Crystal data top
C10H10N2·C4H8N2O2 | Z = 2 |
Mr = 274.32 | F(000) = 292 |
Triclinic, P1 | Dx = 1.283 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 7.9814 (10) Å | Cell parameters from 25 reflections |
b = 8.2719 (10) Å | θ = 10–11° |
c = 12.168 (3) Å | µ = 0.09 mm−1 |
α = 91.779 (18)° | T = 294 K |
β = 106.668 (14)° | Rod-shaped, yellow |
γ = 111.018 (10)° | 0.30 × 0.25 × 0.20 mm |
V = 710.3 (2) Å3 | |
Data collection top
Enraf-Nonius CAD-4 diffractometer | 2244 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.000 |
Graphite monochromator | θmax = 26.3°, θmin = 2.7° |
ω/2θ scans | h = 0→9 |
Absorption correction: ψ scan (Fair, 1990) | k = −10→9 |
Tmin = 0.974, Tmax = 0.982 | l = −15→14 |
2884 measured reflections | 3 standard reflections every 120 min |
2884 independent reflections | intensity decay: 1% |
Refinement top
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.046 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.133 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.08 | w = 1/[σ2(Fo2) + (0.0745P)2 + 0.0913P] where P = (Fo2 + 2Fc2)/3 |
2884 reflections | (Δ/σ)max < 0.001 |
193 parameters | Δρmax = 0.20 e Å−3 |
0 restraints | Δρmin = −0.23 e Å−3 |
Crystal data top
C10H10N2·C4H8N2O2 | γ = 111.018 (10)° |
Mr = 274.32 | V = 710.3 (2) Å3 |
Triclinic, P1 | Z = 2 |
a = 7.9814 (10) Å | Mo Kα radiation |
b = 8.2719 (10) Å | µ = 0.09 mm−1 |
c = 12.168 (3) Å | T = 294 K |
α = 91.779 (18)° | 0.30 × 0.25 × 0.20 mm |
β = 106.668 (14)° | |
Data collection top
Enraf-Nonius CAD-4 diffractometer | 2244 reflections with I > 2σ(I) |
Absorption correction: ψ scan (Fair, 1990) | Rint = 0.000 |
Tmin = 0.974, Tmax = 0.982 | 3 standard reflections every 120 min |
2884 measured reflections | intensity decay: 1% |
2884 independent reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.046 | 0 restraints |
wR(F2) = 0.133 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.08 | Δρmax = 0.20 e Å−3 |
2884 reflections | Δρmin = −0.23 e Å−3 |
193 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 | x | y | z | Uiso*/Ueq | Occ. (<1) |
C1 | 0.41475 (19) | −0.03235 (18) | 0.44813 (11) | 0.0359 (3) | |
C3 | 0.27915 (19) | 0.05366 (18) | −0.04196 (12) | 0.0337 (3) | |
C5 | 0.53352 (19) | 0.26909 (18) | 0.09310 (12) | 0.0343 (3) | |
C10 | 0.6008 (2) | 0.34364 (18) | 0.00366 (12) | 0.0347 (3) | |
C11 | 0.3451 (2) | 0.13324 (19) | −0.13348 (12) | 0.0366 (3) | |
C14 | 0.5746 (2) | 0.51620 (19) | −0.44390 (12) | 0.0414 (4) | |
N1 | 0.43691 (17) | 0.03273 (16) | 0.35668 (10) | 0.0403 (3) | |
N2 | 0.37163 (16) | 0.12052 (15) | 0.06745 (10) | 0.0351 (3) | |
N3 | 0.50272 (17) | 0.27221 (16) | −0.10997 (10) | 0.0384 (3) | |
N4 | 0.5232 (2) | 0.42225 (18) | −0.36865 (11) | 0.0480 (3) | |
O1 | 0.27003 (15) | −0.03360 (16) | 0.26142 (9) | 0.0512 (3) | |
O2 | 0.67083 (19) | 0.45902 (19) | −0.26459 (11) | 0.0635 (4) | |
C2 | 0.2332 (2) | −0.1654 (2) | 0.45309 (14) | 0.0538 (5) | |
H2A | 0.1363 | −0.1868 | 0.3798 | 0.081* | 0.50 |
H2B | 0.1968 | −0.1226 | 0.5130 | 0.081* | 0.50 |
H2C | 0.2498 | −0.2724 | 0.4696 | 0.081* | 0.50 |
H2D | 0.2523 | −0.2011 | 0.5285 | 0.081* | 0.50 |
H2E | 0.1918 | −0.2653 | 0.3953 | 0.081* | 0.50 |
H2F | 0.1388 | −0.1154 | 0.4387 | 0.081* | 0.50 |
C4 | 0.1028 (2) | −0.10884 (19) | −0.07081 (14) | 0.0443 (4) | |
H4A | 0.0866 | −0.1514 | −0.0005 | 0.066* | |
H4B | 0.1132 | −0.1967 | −0.1189 | 0.066* | |
H4C | −0.0044 | −0.0826 | −0.1116 | 0.066* | |
C6 | 0.6350 (2) | 0.3473 (2) | 0.20883 (13) | 0.0439 (4) | |
H6 | 0.5904 | 0.3009 | 0.2683 | 0.053* | |
C7 | 0.7989 (2) | 0.4915 (2) | 0.23377 (14) | 0.0503 (4) | |
H7 | 0.8660 | 0.5425 | 0.3106 | 0.060* | |
C8 | 0.8679 (2) | 0.5643 (2) | 0.14522 (15) | 0.0495 (4) | |
H8 | 0.9809 | 0.6618 | 0.1639 | 0.059* | |
C9 | 0.7705 (2) | 0.4932 (2) | 0.03228 (14) | 0.0440 (4) | |
H9 | 0.8159 | 0.5431 | −0.0261 | 0.053* | |
C12 | 0.2337 (2) | 0.0600 (2) | −0.25797 (13) | 0.0520 (4) | |
H12A | 0.2928 | 0.1336 | −0.3067 | 0.078* | |
H12B | 0.1071 | 0.0554 | −0.2732 | 0.078* | |
H12C | 0.2298 | −0.0559 | −0.2739 | 0.078* | |
C13 | 0.7696 (3) | 0.6519 (2) | −0.42280 (16) | 0.0601 (5) | |
H13A | 0.8442 | 0.6635 | −0.3434 | 0.090* | 0.50 |
H13B | 0.7613 | 0.7623 | −0.4386 | 0.090* | 0.50 |
H13C | 0.8280 | 0.6170 | −0.4729 | 0.090* | 0.50 |
H13D | 0.7781 | 0.6984 | −0.4932 | 0.090* | 0.50 |
H13E | 0.8611 | 0.5995 | −0.3980 | 0.090* | 0.50 |
H13F | 0.7943 | 0.7448 | −0.3637 | 0.090* | 0.50 |
H1 | 0.303 (3) | 0.009 (3) | 0.2045 (19) | 0.071 (6)* | |
H2 | 0.619 (3) | 0.397 (3) | −0.224 (2) | 0.081 (7)* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
C1 | 0.0342 (7) | 0.0367 (7) | 0.0343 (7) | 0.0081 (6) | 0.0137 (6) | 0.0092 (6) |
C3 | 0.0320 (7) | 0.0355 (7) | 0.0373 (7) | 0.0151 (6) | 0.0134 (6) | 0.0086 (6) |
C5 | 0.0334 (7) | 0.0351 (7) | 0.0365 (7) | 0.0131 (6) | 0.0136 (6) | 0.0109 (6) |
C10 | 0.0353 (7) | 0.0358 (7) | 0.0368 (7) | 0.0145 (6) | 0.0149 (6) | 0.0139 (6) |
C11 | 0.0369 (7) | 0.0406 (8) | 0.0363 (8) | 0.0176 (6) | 0.0135 (6) | 0.0101 (6) |
C14 | 0.0463 (9) | 0.0417 (8) | 0.0389 (8) | 0.0135 (7) | 0.0213 (7) | 0.0129 (6) |
N1 | 0.0352 (6) | 0.0453 (7) | 0.0337 (6) | 0.0079 (5) | 0.0103 (5) | 0.0108 (5) |
N2 | 0.0338 (6) | 0.0364 (6) | 0.0367 (6) | 0.0114 (5) | 0.0159 (5) | 0.0121 (5) |
N3 | 0.0391 (7) | 0.0437 (7) | 0.0356 (7) | 0.0157 (6) | 0.0162 (5) | 0.0141 (5) |
N4 | 0.0506 (8) | 0.0569 (8) | 0.0367 (7) | 0.0165 (6) | 0.0188 (6) | 0.0171 (6) |
O1 | 0.0396 (6) | 0.0650 (7) | 0.0332 (6) | 0.0050 (5) | 0.0071 (5) | 0.0153 (5) |
O2 | 0.0572 (8) | 0.0833 (9) | 0.0411 (7) | 0.0148 (7) | 0.0164 (6) | 0.0293 (6) |
C2 | 0.0382 (8) | 0.0633 (10) | 0.0411 (9) | −0.0015 (7) | 0.0113 (7) | 0.0172 (7) |
C4 | 0.0377 (8) | 0.0417 (8) | 0.0493 (9) | 0.0091 (7) | 0.0158 (7) | 0.0057 (7) |
C6 | 0.0466 (9) | 0.0458 (8) | 0.0364 (8) | 0.0113 (7) | 0.0168 (7) | 0.0109 (6) |
C7 | 0.0489 (9) | 0.0466 (9) | 0.0402 (8) | 0.0067 (7) | 0.0073 (7) | 0.0018 (7) |
C8 | 0.0401 (8) | 0.0393 (8) | 0.0572 (10) | 0.0028 (7) | 0.0141 (7) | 0.0090 (7) |
C9 | 0.0401 (8) | 0.0419 (8) | 0.0491 (9) | 0.0098 (7) | 0.0199 (7) | 0.0169 (7) |
C12 | 0.0539 (10) | 0.0612 (10) | 0.0348 (8) | 0.0166 (8) | 0.0122 (7) | 0.0065 (7) |
C13 | 0.0506 (10) | 0.0640 (11) | 0.0518 (10) | 0.0051 (9) | 0.0163 (8) | 0.0210 (8) |
Geometric parameters (Å, º) top
C1—N1 | 1.2811 (18) | C2—H2D | 0.9600 |
C1—C1i | 1.477 (3) | C2—H2E | 0.9600 |
C1—C2 | 1.491 (2) | C2—H2F | 0.9600 |
C3—N2 | 1.3119 (18) | C4—H4A | 0.9600 |
C3—C11 | 1.4434 (19) | C4—H4B | 0.9600 |
C3—C4 | 1.497 (2) | C4—H4C | 0.9600 |
C5—N2 | 1.3723 (18) | C6—C7 | 1.363 (2) |
C5—C6 | 1.404 (2) | C6—H6 | 0.9300 |
C5—C10 | 1.4114 (19) | C7—C8 | 1.403 (2) |
C10—N3 | 1.3676 (19) | C7—H7 | 0.9300 |
C10—C9 | 1.410 (2) | C8—C9 | 1.359 (2) |
C11—N3 | 1.3123 (19) | C8—H8 | 0.9300 |
C11—C12 | 1.495 (2) | C9—H9 | 0.9300 |
C14—N4 | 1.2813 (19) | C12—H12A | 0.9600 |
C14—C14ii | 1.473 (3) | C12—H12B | 0.9600 |
C14—C13 | 1.499 (2) | C12—H12C | 0.9600 |
N1—O1 | 1.4033 (16) | C13—H13A | 0.9600 |
N4—O2 | 1.3956 (18) | C13—H13B | 0.9600 |
O1—H1 | 0.85 (2) | C13—H13C | 0.9600 |
O2—H2 | 0.82 (2) | C13—H13D | 0.9600 |
C2—H2A | 0.9600 | C13—H13E | 0.9600 |
C2—H2B | 0.9600 | C13—H13F | 0.9600 |
C2—H2C | 0.9600 | | |
| | | |
N1—C1—C1i | 115.18 (15) | C3—C4—H4A | 109.5 |
N1—C1—C2 | 124.09 (13) | C3—C4—H4B | 109.5 |
C1i—C1—C2 | 120.73 (15) | H4A—C4—H4B | 109.5 |
N2—C3—C11 | 121.25 (12) | C3—C4—H4C | 109.5 |
N2—C3—C4 | 118.64 (12) | H4A—C4—H4C | 109.5 |
C11—C3—C4 | 120.12 (13) | H4B—C4—H4C | 109.5 |
N2—C5—C6 | 120.23 (12) | C7—C6—C5 | 119.83 (14) |
N2—C5—C10 | 120.40 (13) | C7—C6—H6 | 120.1 |
C6—C5—C10 | 119.37 (13) | C5—C6—H6 | 120.1 |
N3—C10—C9 | 119.98 (13) | C6—C7—C8 | 120.96 (15) |
N3—C10—C5 | 120.59 (13) | C6—C7—H7 | 119.5 |
C9—C10—C5 | 119.43 (13) | C8—C7—H7 | 119.5 |
N3—C11—C3 | 121.11 (13) | C9—C8—C7 | 120.41 (14) |
N3—C11—C12 | 118.26 (13) | C9—C8—H8 | 119.8 |
C3—C11—C12 | 120.63 (13) | C7—C8—H8 | 119.8 |
N4—C14—C14ii | 115.03 (17) | C8—C9—C10 | 119.99 (14) |
N4—C14—C13 | 124.25 (15) | C8—C9—H9 | 120.0 |
C14ii—C14—C13 | 120.72 (16) | C10—C9—H9 | 120.0 |
C1—N1—O1 | 112.39 (12) | C11—C12—H12A | 109.5 |
C3—N2—C5 | 118.23 (11) | C11—C12—H12B | 109.5 |
C11—N3—C10 | 118.35 (12) | H12A—C12—H12B | 109.5 |
C14—N4—O2 | 112.15 (13) | C11—C12—H12C | 109.5 |
N1—O1—H1 | 104.5 (14) | H12A—C12—H12C | 109.5 |
N4—O2—H2 | 102.4 (16) | H12B—C12—H12C | 109.5 |
C1—C2—H2A | 109.5 | C14—C13—H13A | 109.5 |
C1—C2—H2B | 109.5 | C14—C13—H13B | 109.5 |
H2A—C2—H2B | 109.5 | H13A—C13—H13B | 109.5 |
C1—C2—H2C | 109.5 | C14—C13—H13C | 109.5 |
H2A—C2—H2C | 109.5 | H13A—C13—H13C | 109.5 |
H2B—C2—H2C | 109.5 | H13B—C13—H13C | 109.5 |
C1—C2—H2D | 109.5 | C14—C13—H13D | 109.5 |
H2A—C2—H2D | 141.1 | H13A—C13—H13D | 141.1 |
H2B—C2—H2D | 56.3 | H13B—C13—H13D | 56.3 |
H2C—C2—H2D | 56.3 | H13C—C13—H13D | 56.3 |
C1—C2—H2E | 109.5 | C14—C13—H13E | 109.5 |
H2A—C2—H2E | 56.3 | H13A—C13—H13E | 56.3 |
H2B—C2—H2E | 141.1 | H13B—C13—H13E | 141.1 |
H2C—C2—H2E | 56.3 | H13C—C13—H13E | 56.3 |
H2D—C2—H2E | 109.5 | H13D—C13—H13E | 109.5 |
C1—C2—H2F | 109.5 | C14—C13—H13F | 109.5 |
H2A—C2—H2F | 56.3 | H13A—C13—H13F | 56.3 |
H2B—C2—H2F | 56.3 | H13B—C13—H13F | 56.3 |
H2C—C2—H2F | 141.1 | H13C—C13—H13F | 141.1 |
H2D—C2—H2F | 109.5 | H13D—C13—H13F | 109.5 |
H2E—C2—H2F | 109.5 | H13E—C13—H13F | 109.5 |
| | | |
N2—C5—C10—N3 | 2.0 (2) | C3—C11—N3—C10 | −2.0 (2) |
C6—C5—C10—N3 | −178.67 (13) | C12—C11—N3—C10 | 177.37 (13) |
N2—C5—C10—C9 | −178.06 (13) | C9—C10—N3—C11 | −179.87 (13) |
C6—C5—C10—C9 | 1.3 (2) | C5—C10—N3—C11 | 0.1 (2) |
N2—C3—C11—N3 | 2.0 (2) | C14ii—C14—N4—O2 | 179.87 (16) |
C4—C3—C11—N3 | −177.63 (13) | C13—C14—N4—O2 | −0.8 (2) |
N2—C3—C11—C12 | −177.35 (14) | N2—C5—C6—C7 | 177.88 (14) |
C4—C3—C11—C12 | 3.0 (2) | C10—C5—C6—C7 | −1.5 (2) |
C1i—C1—N1—O1 | −179.87 (14) | C5—C6—C7—C8 | 0.4 (3) |
C2—C1—N1—O1 | 0.8 (2) | C6—C7—C8—C9 | 0.9 (3) |
C11—C3—N2—C5 | 0.1 (2) | C7—C8—C9—C10 | −1.1 (3) |
C4—C3—N2—C5 | 179.73 (12) | N3—C10—C9—C8 | 179.93 (14) |
C6—C5—N2—C3 | 178.68 (13) | C5—C10—C9—C8 | 0.0 (2) |
C10—C5—N2—C3 | −2.0 (2) | | |
Symmetry codes: (i) −x+1, −y, −z+1; (ii) −x+1, −y+1, −z−1. |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N2iii | 0.8539 | 2.0451 | 2.8977 | 176.30 |
O2—H2···N3 | 0.8180 | 1.9917 | 2.8053 | 172.85 |
Symmetry code: (iii) x, y−1, z+1. |
Experimental details
Crystal data |
Chemical formula | C10H10N2·C4H8N2O2 |
Mr | 274.32 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 294 |
a, b, c (Å) | 7.9814 (10), 8.2719 (10), 12.168 (3) |
α, β, γ (°) | 91.779 (18), 106.668 (14), 111.018 (10) |
V (Å3) | 710.3 (2) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.30 × 0.25 × 0.20 |
|
Data collection |
Diffractometer | Enraf-Nonius CAD-4 diffractometer |
Absorption correction | ψ scan (Fair, 1990) |
Tmin, Tmax | 0.974, 0.982 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 2884, 2884, 2244 |
Rint | 0.000 |
(sin θ/λ)max (Å−1) | 0.623 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.046, 0.133, 1.08 |
No. of reflections | 2884 |
No. of parameters | 193 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.20, −0.23 |
Selected geometric parameters (Å, º) topC1—N1 | 1.2811 (18) | C14—N4 | 1.2813 (19) |
C1—C1i | 1.477 (3) | C14—C14ii | 1.473 (3) |
C1—C2 | 1.491 (2) | C14—C13 | 1.499 (2) |
C3—N2 | 1.3119 (18) | N1—O1 | 1.4033 (16) |
C5—N2 | 1.3723 (18) | N4—O2 | 1.3956 (18) |
C10—N3 | 1.3676 (19) | O1—H1 | 0.85 (2) |
C11—N3 | 1.3123 (19) | O2—H2 | 0.82 (2) |
| | | |
N1—C1—C1i | 115.18 (15) | C14ii—C14—C13 | 120.72 (16) |
N1—C1—C2 | 124.09 (13) | C1—N1—O1 | 112.39 (12) |
C1i—C1—C2 | 120.73 (15) | C3—N2—C5 | 118.23 (11) |
N2—C3—C11 | 121.25 (12) | C11—N3—C10 | 118.35 (12) |
N3—C11—C3 | 121.11 (13) | C14—N4—O2 | 112.15 (13) |
N4—C14—C14ii | 115.03 (17) | N1—O1—H1 | 104.5 (14) |
N4—C14—C13 | 124.25 (15) | N4—O2—H2 | 102.4 (16) |
| | | |
N2—C5—C10—N3 | 2.0 (2) | C2—C1—N1—O1 | 0.8 (2) |
N2—C3—C11—N3 | 2.0 (2) | C13—C14—N4—O2 | −0.8 (2) |
Symmetry codes: (i) −x+1, −y, −z+1; (ii) −x+1, −y+1, −z−1. |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N2iii | 0.8539 | 2.0451 | 2.8977 | 176.30 |
O2—H2···N3 | 0.8180 | 1.9917 | 2.8053 | 172.85 |
Symmetry code: (iii) x, y−1, z+1. |
Comparison of the bond lengths (Å) and angles (°) in dimethylglyoxime
moieties of (I) with the corresponding values in the related compounds
(II), (III), (IV) and (V). top | | (I) | | (II) | (III) | (IV) | (V) |
C1-Ctrans | | 1.477 (3) | 1.473 (3) | 1.562 (18) | 1.53 | 1.515 | 1.55 |
C1-Ccis | | 1.491 (2) | 1.499 (2) | 1.479 (15) | 1.485 | 1.47 | 1.49 |
C1-N1 | | 1.281 (2) | 1.281 (2) | 1.253 (11) | 1.225 | 1.25 | 1.29 |
N1-O1 | | 1.403 (2) | 1.396 (2) | 1.321 (21) | 1.375 | 1.345 | 1.36 |
O1-H1 | | 0.85 (2) | 0.82 (2) | 1.02 (4) | - | - | - |
Ccis-C1-Ctrans | | 120.7 (2) | 120.7 (2) | 120.4 | 122.5 | 122.3 | 117 |
N1-C1-Ctrans | | 115.2 (2) | 115.0 (2) | 113.8 | 111.0 | 112.8 | 113 |
N1-C1-Ccis | | 124.1 (2) | 124.3 (2) | 126.0 | 126.5 | 124.9 | 131 |
C1-N1-O1 | | 112.4 (2) | 112.2 (2) | 111.4 | 121 | 119.5 | 111 |
N1-O1-H1 | | 104.5 (14) | 102.4 (16) | 109.6 | 102 | - | - |
Intermolecular hydrogen bonding has received considerable attention among the directional non-covalent intermolecular interactions (Etter et al., 1990), which combines moderate strength and directionality (Karle et al., 1996) in designing the compounds to form supramolecular structures.
Oxime (–C═N—OH) groups possess stronger hydrogen-bonding capabilities than alcohols, phenols and carboxylic acids (Marsman et al., 1999). The hydrogen-bond systems in the crystals of oximes have been analysed and a correlation between a pattern of hydrogen bonding and N—O bond lengths is suggested (Bertolasi et al., 1982). The configurational and/or conformational isomers of glyoxime derivatives (dioximes) have also been analysed (Chertanova et al., 1994).
Oxime/oximato metal complexes have been investigated actively since the beginning of the last century of the millennium (Kukushkin & Pombeiro, 1999). In general, oxime and dioxime derivatives are very important compounds in chemical industry and medicine. Dimethylglyoxime is actually the first selective organic reagent applied in the analysis of metals (Tshugaeff, 1905).
Crystals of dimethylglyoxime were reported by McCrone (1949) to be triclinic and its structure was undertaken by Merritt & Lanterman (1952). A neutron diffraction refinement of the crystal structure of the dimethylgluoxime clarified the existence of the O—H (classical structure) bonding rather than N—H (zwitterion structure) (Hamilton, 1961).
Quinoxaline derivatives are very useful compounds with well known biological activities (Cheeseman & Werstiuk, 1978; Sato, 1996). Some of the quinoxaline derivatives act as in vitro anticancer compounds (Corona et al., 1998).
The structure of 2,3-dimethylquinoxaline was reported by Wozniak et al., (1990) to be monoclinic. The crystal structures containing 2,3-disubstituted derivatives of quinoxaline have aroused considerable interest because of the repulsions between the neighbouring substituents (Visser et al., 1968; Visser & Vos, 1971; Lipkovski et al., 1985; Krigier et al., 1985).
The crystal structure determination of the title molecule, (I), was carried out in order to understand the strength of the hydrogen-bonding capabilities of the oxime groups having the classical (–C═N—O—H) structures. As shown in Fig. 1, the title compound, (I), consists of hydrogen-bonded 2,3-dimethylquinoxaline and dimethylglyoxime moieties. Both dimethylglyoximes are located on an inversion centre and there are two half-molecules in the asymmetric unit.
The bond lengths and angles of the 2,3-dimethylquinoxaline moiety are in accordance with the reported values (Wozniak et al., 1990).
In the dimethylglyoxime moieties, the O—N, C═N, C—C bond lengths and C═N—O bond angles are larger, while the O—H, C—C' bonds and N—O—H, C—C═N, C'-C═N angles are smaller than the corresponding ones, reported in dimethylglyoxime (Hamilton, 1961) (Table 2). A comparison of the bond lengths and angles of the dimethylgluoxime moieties in the title compound, (I), with the corresponding ones in dimethylglyoxime, (II) (Hamilton, 1961), nickel dimethylglyoxime, (III) (Godkycki & Rundle, 1953), copper dimethylglyoxime, (IV) (Frasson et al., 1959) and acetoxime, (V) (Bierlein & Lingafelter, 1951), are given in Table 2.
As can be seen from the packing diagram (Fig. 2), there are intermolecular hydrogen bonds between the hydroxy H atoms of the dimethylglyoxime and N atoms of the 2,3-dimethylquinoxaline moieties (Table 3). The intermolecular hydrogen bonds are highly effective in forming the polymeric chains. Dipole-dipole and van der Waals interactions are also effective in the molecular packing.
An examination of the deviations from the least-squares planes through the individual rings shows that rings A (C5—C10) and B (C5/N2/C3/C11/N3/C10) are nearly planar with maximum deviations for the C5 [-0.007 (2) Å] and C5 [0.016 (2) Å] atoms, respectively.