organic compounds
N2′,N5′-Diisopropylidenepyrazine-2,5-dicarbohydrazide dihydrate
aThe Key Laboratory for Functional Materials of Fujian Higher Education, College of Materials Science and Engineering, Huaqiao University, Quanzhou 362021, Fujian, People's Republic of China
*Correspondence e-mail: new_19820128@yahoo.com.cn
In the title compound, C12H16N6O2·2H2O, the organic molecule, except for the methyl H atoms, is essentially planar, the r.m.s. deviation from planarity being 0.044 Å. The is stabilized by intermolecular O—H⋯O and O—H⋯N hydrogen bonds which form chains.
Experimental
Crystal data
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Refinement
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Data collection: CrystalClear (Rigaku, 2000); cell CrystalClear; data reduction: CrystalClear; 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.
Supporting information
10.1107/S1600536808002973/wn2238sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536808002973/wn2238Isup2.hkl
The title compound was prepared by the hydroponics method. 2,5-Pyrazinedihydrazide, as a yellow powder, was synthesized from 2,5-pyrazinedicarboxylic acid dihydrate by esterification and acylation (Wu et al., 2003). 2,5-Pyrazinedihydrazide (20 mg) was dissolved in acetone (20 ml) with stirring for one hour. Transparent orange crystals of the title compound were obtained from the mother liquor by slow evaporation at room temperature after one week.
The positions of the O-bound H atoms were located from a difference Fourier map and refined freely; the refined O—H distances lie in the range 0.76 (4) - 0.99 (7) Å. The H atoms of methyl groups C11 and C12 were also located in a difference map. Other H atoms bonded to C or N were placed in calculated positions. All C– and N-bound C atoms were refined as riding, with N—H = 0.86 Å, Csp2—H = 0.93 Å and Csp3—H = 0.96 Å; Uiso(H) = 1.2Ueq(C,N).
Data collection: CrystalClear (Rigaku, 2000); cell
CrystalClear (Rigaku, 2000); data reduction: CrystalClear (Rigaku, 2000); 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).Fig. 1. The structure of the title compound. Displacement ellipsoids are drawn at the 30% probability level. Hydrogen atoms are shown as spheres of arbitrary radius. | |
Fig. 2. A packing diagram of the title compound, showing the hydrogen bond interactions as dashed lines. |
C12H16N6O2·2H2O | Z = 2 |
Mr = 312.34 | F(000) = 332 |
Triclinic, P1 | Dx = 1.333 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 7.1924 (5) Å | Cell parameters from 1817 reflections |
b = 9.9409 (8) Å | θ = 2.8–22.6° |
c = 11.0903 (9) Å | µ = 0.10 mm−1 |
α = 80.261 (6)° | T = 296 K |
β = 84.605 (5)° | Prism, orange |
γ = 89.537 (6)° | 0.50 × 0.16 × 0.16 mm |
V = 778.03 (10) Å3 |
Bruker P4 diffractometer | 3643 independent reflections |
Radiation source: fine-focus sealed tube | 1540 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.049 |
Detector resolution: 14.6306 pixels mm-1 | θmax = 27.9°, θmin = 1.9° |
CCD_Profile_fitting scans | h = −9→9 |
Absorption correction: multi-scan (CrystalClear (Rigaku, 2000) | k = −13→13 |
Tmin = 0.965, Tmax = 0.984 | l = −14→14 |
12989 measured reflections |
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)] = 0.065 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.209 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.00 | w = 1/[σ2(Fo2) + (0.0979P)2 + 0.03P] where P = (Fo2 + 2Fc2)/3 |
3643 reflections | (Δ/σ)max < 0.001 |
224 parameters | Δρmax = 0.23 e Å−3 |
0 restraints | Δρmin = −0.25 e Å−3 |
C12H16N6O2·2H2O | γ = 89.537 (6)° |
Mr = 312.34 | V = 778.03 (10) Å3 |
Triclinic, P1 | Z = 2 |
a = 7.1924 (5) Å | Mo Kα radiation |
b = 9.9409 (8) Å | µ = 0.10 mm−1 |
c = 11.0903 (9) Å | T = 296 K |
α = 80.261 (6)° | 0.50 × 0.16 × 0.16 mm |
β = 84.605 (5)° |
Bruker P4 diffractometer | 3643 independent reflections |
Absorption correction: multi-scan (CrystalClear (Rigaku, 2000) | 1540 reflections with I > 2σ(I) |
Tmin = 0.965, Tmax = 0.984 | Rint = 0.049 |
12989 measured reflections |
R[F2 > 2σ(F2)] = 0.065 | 0 restraints |
wR(F2) = 0.209 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.00 | Δρmax = 0.23 e Å−3 |
3643 reflections | Δρmin = −0.25 e Å−3 |
224 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
N5 | 0.4457 (3) | 0.9409 (2) | 0.18538 (19) | 0.0570 (6) | |
H5A | 0.3273 | 0.9549 | 0.1898 | 0.068* | |
N2 | 0.2140 (3) | 0.8126 (2) | 0.05799 (19) | 0.0543 (6) | |
N1 | 0.3605 (3) | 0.6324 (2) | −0.09296 (18) | 0.0538 (6) | |
N3 | 0.1252 (3) | 0.5072 (2) | −0.22285 (19) | 0.0563 (6) | |
H3A | 0.2443 | 0.4978 | −0.2334 | 0.068* | |
N4 | 0.0048 (3) | 0.4399 (2) | −0.2847 (2) | 0.0580 (6) | |
O1 | −0.1200 (2) | 0.6055 (2) | −0.12989 (18) | 0.0732 (6) | |
C3 | 0.3958 (3) | 0.7863 (2) | 0.0460 (2) | 0.0482 (6) | |
C1 | 0.1776 (3) | 0.6578 (2) | −0.0798 (2) | 0.0463 (6) | |
N6 | 0.5616 (3) | 1.0070 (2) | 0.25097 (19) | 0.0580 (6) | |
C5 | 0.0469 (4) | 0.5873 (3) | −0.1459 (2) | 0.0515 (6) | |
C6 | 0.5253 (4) | 0.8541 (3) | 0.1146 (2) | 0.0578 (7) | |
O2 | 0.6916 (3) | 0.8306 (2) | 0.1056 (2) | 0.0898 (8) | |
C2 | 0.1058 (3) | 0.7480 (3) | −0.0051 (2) | 0.0543 (7) | |
H2A | −0.0220 | 0.7639 | 0.0012 | 0.065* | |
C4 | 0.4690 (3) | 0.6970 (3) | −0.0294 (2) | 0.0551 (7) | |
H4A | 0.5970 | 0.6818 | −0.0359 | 0.066* | |
C10 | 0.4878 (4) | 1.0898 (3) | 0.3168 (2) | 0.0573 (7) | |
C12 | 0.6179 (5) | 1.1587 (4) | 0.3842 (3) | 0.0696 (9) | |
H12A | 0.592 (4) | 1.136 (3) | 0.468 (3) | 0.084* | |
H12B | 0.609 (4) | 1.264 (3) | 0.364 (2) | 0.084* | |
H12C | 0.742 (5) | 1.131 (3) | 0.363 (3) | 0.084* | |
C7 | 0.0747 (4) | 0.3704 (3) | −0.3630 (2) | 0.0581 (7) | |
C9 | −0.0602 (4) | 0.2998 (3) | −0.4275 (3) | 0.0764 (9) | |
H9A | −0.1853 | 0.3262 | −0.4041 | 0.115* | |
H9B | −0.0484 | 0.2028 | −0.4048 | 0.115* | |
H9C | −0.0329 | 0.3253 | −0.5147 | 0.115* | |
C11 | 0.2879 (4) | 1.1256 (3) | 0.3329 (3) | 0.0796 (9) | |
H11A | 0.2339 | 1.0799 | 0.4115 | 0.095* | |
H11B | 0.2237 | 1.0985 | 0.2688 | 0.095* | |
H11C | 0.2754 | 1.2226 | 0.3280 | 0.095* | |
C8 | 0.2769 (4) | 0.3527 (3) | −0.4004 (3) | 0.0831 (10) | |
H8A | 0.2988 | 0.3727 | −0.4884 | 0.125* | |
H8B | 0.3122 | 0.2603 | −0.3720 | 0.125* | |
H8C | 0.3498 | 0.4138 | −0.3651 | 0.125* | |
O3 | 0.5953 (4) | 0.4902 (3) | −0.2671 (2) | 0.0869 (8) | |
O4 | −0.0209 (4) | 0.9821 (3) | 0.2080 (3) | 0.0965 (9) | |
H3D | 0.710 (6) | 0.479 (3) | −0.271 (3) | 0.106 (14)* | |
H3C | 0.556 (7) | 0.526 (5) | −0.215 (4) | 0.15 (2)* | |
H4C | 0.032 (9) | 0.939 (7) | 0.138 (6) | 0.28 (3)* | |
H4D | −0.127 (6) | 0.985 (4) | 0.219 (3) | 0.096 (14)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
N5 | 0.0391 (12) | 0.0708 (14) | 0.0701 (14) | 0.0022 (10) | −0.0142 (10) | −0.0330 (12) |
N2 | 0.0372 (12) | 0.0665 (14) | 0.0653 (13) | 0.0044 (10) | −0.0077 (10) | −0.0272 (11) |
N1 | 0.0385 (12) | 0.0677 (14) | 0.0604 (13) | 0.0037 (10) | −0.0050 (10) | −0.0260 (11) |
N3 | 0.0395 (12) | 0.0720 (14) | 0.0655 (13) | −0.0035 (11) | −0.0071 (10) | −0.0333 (11) |
N4 | 0.0466 (13) | 0.0693 (14) | 0.0660 (14) | −0.0023 (11) | −0.0126 (10) | −0.0298 (12) |
O1 | 0.0349 (11) | 0.0945 (15) | 0.1046 (15) | 0.0051 (10) | −0.0114 (9) | −0.0553 (12) |
C3 | 0.0375 (14) | 0.0582 (15) | 0.0520 (14) | 0.0020 (12) | −0.0073 (11) | −0.0166 (12) |
C1 | 0.0358 (14) | 0.0528 (15) | 0.0528 (15) | 0.0015 (11) | −0.0047 (11) | −0.0159 (12) |
N6 | 0.0449 (13) | 0.0728 (15) | 0.0641 (13) | −0.0030 (11) | −0.0125 (10) | −0.0293 (12) |
C5 | 0.0415 (15) | 0.0583 (16) | 0.0574 (15) | 0.0009 (13) | −0.0066 (12) | −0.0167 (13) |
C6 | 0.0413 (16) | 0.0764 (18) | 0.0618 (17) | 0.0017 (14) | −0.0084 (13) | −0.0274 (14) |
O2 | 0.0381 (11) | 0.1373 (19) | 0.1155 (17) | 0.0089 (11) | −0.0134 (10) | −0.0795 (15) |
C2 | 0.0362 (14) | 0.0670 (17) | 0.0659 (16) | 0.0045 (12) | −0.0075 (12) | −0.0278 (14) |
C4 | 0.0363 (14) | 0.0734 (18) | 0.0621 (16) | 0.0030 (13) | −0.0061 (11) | −0.0297 (14) |
C10 | 0.0491 (17) | 0.0667 (17) | 0.0614 (16) | −0.0036 (14) | −0.0110 (13) | −0.0225 (14) |
C12 | 0.0596 (19) | 0.085 (2) | 0.0721 (19) | −0.0070 (18) | −0.0121 (16) | −0.0323 (18) |
C7 | 0.0552 (17) | 0.0645 (17) | 0.0602 (16) | −0.0022 (14) | −0.0103 (13) | −0.0239 (14) |
C9 | 0.068 (2) | 0.086 (2) | 0.088 (2) | −0.0015 (17) | −0.0230 (16) | −0.0406 (17) |
C11 | 0.0578 (19) | 0.091 (2) | 0.104 (2) | 0.0091 (16) | −0.0141 (16) | −0.0544 (19) |
C8 | 0.061 (2) | 0.114 (3) | 0.090 (2) | 0.0072 (18) | −0.0084 (16) | −0.059 (2) |
O3 | 0.0485 (14) | 0.128 (2) | 0.1033 (18) | 0.0056 (13) | −0.0192 (12) | −0.0660 (16) |
O4 | 0.0506 (15) | 0.122 (2) | 0.137 (2) | 0.0060 (14) | −0.0248 (14) | −0.0695 (17) |
N5—C6 | 1.352 (3) | C10—C11 | 1.480 (4) |
N5—N6 | 1.393 (3) | C10—C12 | 1.489 (4) |
N5—H5A | 0.8600 | C12—H12A | 0.92 (3) |
N2—C2 | 1.330 (3) | C12—H12B | 1.03 (3) |
N2—C3 | 1.330 (3) | C12—H12C | 0.95 (3) |
N1—C4 | 1.335 (3) | C7—C8 | 1.492 (4) |
N1—C1 | 1.337 (3) | C7—C9 | 1.502 (3) |
N3—C5 | 1.346 (3) | C9—H9A | 0.9600 |
N3—N4 | 1.394 (3) | C9—H9B | 0.9600 |
N3—H3A | 0.8600 | C9—H9C | 0.9600 |
N4—C7 | 1.264 (3) | C11—H11A | 0.9600 |
O1—C5 | 1.213 (3) | C11—H11B | 0.9600 |
C3—C4 | 1.388 (3) | C11—H11C | 0.9600 |
C3—C6 | 1.489 (3) | C8—H8A | 0.9600 |
C1—C2 | 1.386 (3) | C8—H8B | 0.9600 |
C1—C5 | 1.492 (3) | C8—H8C | 0.9600 |
N6—C10 | 1.272 (3) | O3—H3D | 0.83 (4) |
C6—O2 | 1.215 (3) | O3—H3C | 0.76 (5) |
C2—H2A | 0.9300 | O4—H4C | 0.99 (7) |
C4—H4A | 0.9300 | O4—H4D | 0.76 (4) |
C6—N5—N6 | 117.9 (2) | C11—C10—C12 | 116.8 (2) |
C6—N5—H5A | 121.1 | C10—C12—H12A | 112.0 (18) |
N6—N5—H5A | 121.1 | C10—C12—H12B | 112.1 (16) |
C2—N2—C3 | 116.6 (2) | H12A—C12—H12B | 106 (2) |
C4—N1—C1 | 116.5 (2) | C10—C12—H12C | 108.8 (17) |
C5—N3—N4 | 117.1 (2) | H12A—C12—H12C | 108 (3) |
C5—N3—H3A | 121.5 | H12B—C12—H12C | 110 (2) |
N4—N3—H3A | 121.5 | N4—C7—C8 | 127.2 (2) |
C7—N4—N3 | 118.5 (2) | N4—C7—C9 | 116.7 (3) |
N2—C3—C4 | 121.7 (2) | C8—C7—C9 | 116.1 (2) |
N2—C3—C6 | 119.6 (2) | C7—C9—H9A | 109.5 |
C4—C3—C6 | 118.7 (2) | C7—C9—H9B | 109.5 |
N1—C1—C2 | 121.4 (2) | H9A—C9—H9B | 109.5 |
N1—C1—C5 | 119.6 (2) | C7—C9—H9C | 109.5 |
C2—C1—C5 | 119.0 (2) | H9A—C9—H9C | 109.5 |
C10—N6—N5 | 118.2 (2) | H9B—C9—H9C | 109.5 |
O1—C5—N3 | 123.8 (2) | C10—C11—H11A | 109.4 |
O1—C5—C1 | 119.8 (2) | C10—C11—H11B | 109.8 |
N3—C5—C1 | 116.4 (2) | H11A—C11—H11B | 109.8 |
O2—C6—N5 | 123.5 (2) | C10—C11—H11C | 109.9 |
O2—C6—C3 | 120.6 (2) | H11A—C11—H11C | 109.8 |
N5—C6—C3 | 115.9 (2) | H11B—C11—H11C | 108.2 |
N2—C2—C1 | 122.1 (2) | C7—C8—H8A | 109.5 |
N2—C2—H2A | 118.9 | C7—C8—H8B | 109.5 |
C1—C2—H2A | 118.9 | H8A—C8—H8B | 109.5 |
N1—C4—C3 | 121.8 (2) | C7—C8—H8C | 109.5 |
N1—C4—H4A | 119.1 | H8A—C8—H8C | 109.5 |
C3—C4—H4A | 119.1 | H8B—C8—H8C | 109.5 |
N6—C10—C11 | 127.2 (2) | H3D—O3—H3C | 115 (4) |
N6—C10—C12 | 116.0 (3) | H4C—O4—H4D | 117 (4) |
C5—N3—N4—C7 | 175.9 (2) | N2—C3—C6—O2 | 179.5 (3) |
C2—N2—C3—C4 | 0.7 (4) | C4—C3—C6—O2 | −0.7 (4) |
C2—N2—C3—C6 | −179.6 (2) | N2—C3—C6—N5 | −0.5 (4) |
C4—N1—C1—C2 | 0.7 (4) | C4—C3—C6—N5 | 179.3 (2) |
C4—N1—C1—C5 | −178.8 (2) | C3—N2—C2—C1 | −0.1 (4) |
C6—N5—N6—C10 | 179.3 (2) | N1—C1—C2—N2 | −0.6 (4) |
N4—N3—C5—O1 | −1.4 (4) | C5—C1—C2—N2 | 178.9 (2) |
N4—N3—C5—C1 | 179.63 (19) | C1—N1—C4—C3 | −0.2 (4) |
N1—C1—C5—O1 | 176.7 (2) | N2—C3—C4—N1 | −0.5 (4) |
C2—C1—C5—O1 | −2.8 (4) | C6—C3—C4—N1 | 179.7 (2) |
N1—C1—C5—N3 | −4.3 (3) | N5—N6—C10—C11 | 0.0 (4) |
C2—C1—C5—N3 | 176.2 (2) | N5—N6—C10—C12 | −179.5 (2) |
N6—N5—C6—O2 | 0.2 (4) | N3—N4—C7—C8 | −1.3 (4) |
N6—N5—C6—C3 | −179.8 (2) | N3—N4—C7—C9 | −180.0 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
N5—H5A···O4 | 0.86 | 2.51 | 3.369 (4) | 177 |
N3—H3A···O3 | 0.86 | 2.52 | 3.377 (4) | 176 |
O3—H3D···N4i | 0.83 (4) | 2.15 (4) | 2.977 (3) | 177 (3) |
O3—H3D···O1i | 0.83 (4) | 2.57 (3) | 3.006 (3) | 115 (3) |
O3—H3C···N1 | 0.76 (5) | 2.24 (5) | 2.974 (3) | 162 (5) |
O4—H4C···N2 | 0.99 (7) | 2.05 (7) | 2.972 (3) | 153 (6) |
O4—H4D···N6ii | 0.76 (4) | 2.25 (4) | 3.010 (4) | 177 (4) |
O4—H4D···O2ii | 0.76 (4) | 2.58 (4) | 2.984 (3) | 115 (3) |
Symmetry codes: (i) x+1, y, z; (ii) x−1, y, z. |
Experimental details
Crystal data | |
Chemical formula | C12H16N6O2·2H2O |
Mr | 312.34 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 296 |
a, b, c (Å) | 7.1924 (5), 9.9409 (8), 11.0903 (9) |
α, β, γ (°) | 80.261 (6), 84.605 (5), 89.537 (6) |
V (Å3) | 778.03 (10) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.50 × 0.16 × 0.16 |
Data collection | |
Diffractometer | Bruker P4 diffractometer |
Absorption correction | Multi-scan (CrystalClear (Rigaku, 2000) |
Tmin, Tmax | 0.965, 0.984 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 12989, 3643, 1540 |
Rint | 0.049 |
(sin θ/λ)max (Å−1) | 0.658 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.065, 0.209, 1.00 |
No. of reflections | 3643 |
No. of parameters | 224 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.23, −0.25 |
Computer programs: CrystalClear (Rigaku, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
N5—H5A···O4 | 0.86 | 2.51 | 3.369 (4) | 176.8 |
N3—H3A···O3 | 0.86 | 2.52 | 3.377 (4) | 175.6 |
O3—H3D···N4i | 0.83 (4) | 2.15 (4) | 2.977 (3) | 177 (3) |
O3—H3D···O1i | 0.83 (4) | 2.57 (3) | 3.006 (3) | 115 (3) |
O3—H3C···N1 | 0.76 (5) | 2.24 (5) | 2.974 (3) | 162 (5) |
O4—H4C···N2 | 0.99 (7) | 2.05 (7) | 2.972 (3) | 153 (6) |
O4—H4D···N6ii | 0.76 (4) | 2.25 (4) | 3.010 (4) | 177 (4) |
O4—H4D···O2ii | 0.76 (4) | 2.58 (4) | 2.984 (3) | 115 (3) |
Symmetry codes: (i) x+1, y, z; (ii) x−1, y, z. |
Acknowledgements
We are grateful for financial support from the National Science Foundation of Fujian Province of China (No. E0610017, 2003 F 006).
References
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Research into amine and hydrazine derivatives has become a major growth area of biological chemistry, structural chemistry, medicine and catalysis. As part of our work in this area, we here present the crystal structure of the title compound.
The structure of the title compound is illustrated in Fig. 1. Except for the H atoms of the methyl groups, the organic molecule is essentially planar, the r.m.s. deviation being 0.044 Å. In the hydrazino fragment, the N—N bond lengths are normal, while the C—N distances are slightly longer than those in pyrazine-2-carbohydrazide (Wardell et al., 2006). In the crystal structure, molecules are linked to form chains by intermolecular O—H···O and O—H···N hydrogen bonds (Fig. 2 and Table 1).