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2,2,7,7-Tetra­methyl-1,2,3,6,7,8-hexa­hydro­cinnolino[5,4,3-cde]cinnoline

aLianyungang Teachers' College, Lianyungang 222006, People's Republic of China, and bSchool of Chemistry and Chemical Engineering, Xuzhou Normal University, Xuzhou 221116, People's Republic of China
*Correspondence e-mail: laotu2001@263.net

(Received 23 December 2008; accepted 25 December 2008; online 8 January 2009)

The asymmetric unit of the title compound, C16H20N4, contains two half-mol­ecules, which are completed by crystallographic inversion symmetry. The pyridazine rings are conjugated and the cyclo­hexane rings adopt envelope conformations.

Related literature

For general background, see: Ischikawa et al. (1992[Ischikawa, H., Umeda, T. & Kajikawa, K. (1992). Japanese Patent No. 04 187 677.]); Labovitz et al. (1990[Labovitz, J., Guilford, W., Liang, Y., Fang, L. & Patterson, T. (1990). European Patent No. 363 236.]); Mizutani, Shiroshita, Okuda et al. (1989[Mizutani, M., Shiroshita, M., Okuda, H., Mito, N. & Sakaki, M. (1989). European Patent No. 320 782.]); Patterson (1992[Patterson, T. G. (1992). US Patent No. 5 129 940.]); Coghlan et al. (1989[Coghlan, M. J., Driekorn, B. A., Suhr, R. G. & Jourdan, G. P. (1989). European Patent No. 326328.]); Mizutani, Shiroshita, Sakaki et al. (1989[Mizutani, M., Shiroshita, M., Sakaki, M., Mito, N. & Okuda, H. (1989). European Patent No. 320 793.]b); Munro & Bit (1987[Munro, D. & Bit, R. (1987). UK Patent No. 2 189 238.]); Inoue et al. (1993[Inoue, S., Yasaki, A., Mochizuki, H., Tutsumi, H., Murata, M. & Sakane, K. (1993). Japanese Patent No. 05 213 951.]); Tutsumi et al. (1992[Tutsumi, H., Terasawa, T., Barret, D., Mutata, M., Sakane, K., Yazaki, A. & Inoue, S. (1992). Japanese Patent No. 9 215 584.]); Yokomoto et al. (1992[Yokomoto, M., Yazaki, A., Hayashi, N., Hatono, S., Inoue, S. & Kuramoto, Y. (1992). European Patent No. 4 700 578.]); Miyamoto et al. (1990[Miyamoto, K., Matsumoto, J. & Nakamura, S. (1990). Japanese Patent No. 02 096 570.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]). For ring-puckering parameters, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]).

[Scheme 1]

Experimental

Crystal data
  • C16H20N4

  • Mr = 268.36

  • Monoclinic, P 21 /n

  • a = 12.819 (4) Å

  • b = 8.441 (3) Å

  • c = 13.310 (4) Å

  • β = 95.462 (5)°

  • V = 1433.7 (8) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 298 (2) K

  • 0.33 × 0.28 × 0.21 mm

Data collection
  • Bruker SMART CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 1998[Bruker (1998). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.975, Tmax = 0.984

  • 7218 measured reflections

  • 2518 independent reflections

  • 1416 reflections with I > 2σ(I)

  • Rint = 0.048

Refinement
  • R[F2 > 2σ(F2)] = 0.052

  • wR(F2) = 0.179

  • S = 1.04

  • 2518 reflections

  • 185 parameters

  • H-atom parameters constrained

  • Δρmax = 0.18 e Å−3

  • Δρmin = −0.20 e Å−3

Data collection: SMART (Bruker, 1998[Bruker (1998). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 1998[Bruker (1998). SMART, SAINT and SADABS. 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

It is well known that six-membered nitrogen-containing heterocycles are abundant in numerous natural products that exhibit important biological properties. For example, cinnolines and their derivatives are widely used as agrochemical and pharmaceutical drugs (Ischikawa et al., 1992; Labovitz et al., 1990; Mizutani, Shiroshita, Okuda et al., 1989; Patterson, 1992; Coghlan et al., 1989; Mizutani, Shiroshita, Sakaki et al., 1989; Munro & Bit, 1987). They can act as microbicides, pollen suppressants, fungicides and herbicides in agrochemistry. They can also be used as bactericides in pharmaceutical industry (Inoue et al., 1993; Tutsumi et al., 1992; Yokomoto et al., 1992; Miyamoto et al., 1990). The chemistry of cinnolines has received much attention based on the above facts.

The asymmetric unit of the title compound contains two-halves of centrosymmetric molecules (Fig. 1). The bond lengths (Allen et al., 1987) and angles are within normal ranges. The pyridazine rings A (N1/N2/C1-C3/C2A) and C (N3/N4/C9-C11/C10B) are, of course, planar and they are oriented at a dihedral angle of 43.89 (3)° [symmetry codes: (A) 2 - x, -y, -z; (B) 1 - x, -y, -z]. The cyclohexene rings B (C1/C2/C5/C6/C3A/C4A) and D (C9/C10/C13/C14/C11B/C12B), having total puckering amplitudes, QT, of 0.579 (3) and 0.566 Å, respectively, half-chair conformations [ϕ = -72.92 (3)° and θ = 103.84 (4)°; ϕ = 110.31 (4)° and θ = 74.14 (4)°] (Cremer & Pople, 1975) [symmetry codes: (A) 2 - x, -y, -z; (B) 1 - x, -y, -z].

Related literature top

For general background, see: Ischikawa et al. (1992); Labovitz et al. (1990); Mizutani, Shiroshita, Okuda et al. (1989); Patterson (1992); Coghlan et al. (1989); Mizutani, Shiroshita, Sakaki et al. (1989b); Munro & Bit (1987); Inoue et al. (1993); Tutsumi et al. (1992); Yokomoto et al. (1992); Miyamoto et al. (1990). For bond-length data, see: Allen et al. (1987). For ring-puckering parameters, see: Cremer & Pople (1975).

Experimental top

The title compound was prepared by the reaction of 3,4,6,7-tetrahydro- 3,3,6,6,9-pentamethyl-2H-xanthene-1,8(5H,9H)-dione (2 mmol) and hydrazine hydrate (8 mmol, 80%) in ethanol (8 ml), stirring at 353 K (yield; 88%, m.p. 562-563 K). Crystals suitable for X-ray analysis were obtained from an ethanol solution by slow evaporation.

Refinement top

H atoms were positioned geometrically, with C-H = 0.97 and 0.96 Å for methylene and methyl H and constrained to ride on their parent atoms, with Uiso(H) = xUeq(C), where x = 1.5 for methyl H and x = 1.2 for methylene H atoms.

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT (Bruker, 1998); 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).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level [symmetry code (A): -x, -y, -z].
2,2,7,7-Tetramethyl-1,2,3,6,7,8-hexahydrocinnolino[5,4,3-cde]cinnoline top
Crystal data top
C16H20N4F(000) = 576
Mr = 268.36Dx = 1.243 Mg m3
Monoclinic, P21/nMelting point = 562–563 K
Hall symbol: -P 2ynMo Kα radiation, λ = 0.71073 Å
a = 12.819 (4) ÅCell parameters from 1230 reflections
b = 8.441 (3) Åθ = 2.3–23.2°
c = 13.310 (4) ŵ = 0.08 mm1
β = 95.462 (5)°T = 298 K
V = 1433.7 (8) Å3Block, pale yellow
Z = 40.33 × 0.28 × 0.21 mm
Data collection top
Bruker SMART CCD area-detector
diffractometer
2518 independent reflections
Radiation source: fine-focus sealed tube1416 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.048
ϕ and ω scansθmax = 25.0°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Bruker, 1998)
h = 1515
Tmin = 0.975, Tmax = 0.984k = 910
7218 measured reflectionsl = 1514
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) = 0.179H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + 0.3048P]
where P = (Fo2 + 2Fc2)/3
2518 reflections(Δ/σ)max < 0.001
185 parametersΔρmax = 0.18 e Å3
0 restraintsΔρmin = 0.20 e Å3
Crystal data top
C16H20N4V = 1433.7 (8) Å3
Mr = 268.36Z = 4
Monoclinic, P21/nMo Kα radiation
a = 12.819 (4) ŵ = 0.08 mm1
b = 8.441 (3) ÅT = 298 K
c = 13.310 (4) Å0.33 × 0.28 × 0.21 mm
β = 95.462 (5)°
Data collection top
Bruker SMART CCD area-detector
diffractometer
2518 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 1998)
1416 reflections with I > 2σ(I)
Tmin = 0.975, Tmax = 0.984Rint = 0.048
7218 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0520 restraints
wR(F2) = 0.179H-atom parameters constrained
S = 1.04Δρmax = 0.18 e Å3
2518 reflectionsΔρmin = 0.20 e Å3
185 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
N11.11488 (18)0.2369 (3)0.00759 (19)0.0510 (7)
N21.16426 (18)0.1239 (3)0.04672 (19)0.0513 (7)
N30.50653 (19)0.2577 (3)0.08920 (17)0.0469 (6)
N40.56253 (19)0.1517 (3)0.14224 (17)0.0470 (6)
C11.0250 (2)0.2044 (3)0.04438 (19)0.0394 (7)
C20.97626 (18)0.0553 (3)0.02796 (18)0.0350 (7)
C31.1205 (2)0.0146 (3)0.06568 (19)0.0408 (7)
C41.1709 (2)0.1336 (3)0.1275 (2)0.0522 (8)
H4A1.24630.11850.11870.063*
H4B1.14790.11610.19820.063*
C50.9742 (2)0.3236 (4)0.1053 (2)0.0483 (8)
H5A0.99060.42870.08190.058*
H5B1.00300.31460.17520.058*
C60.8543 (2)0.3047 (3)0.0998 (2)0.0456 (7)
C70.8054 (2)0.3422 (4)0.0065 (2)0.0602 (9)
H7A0.83240.27040.05360.090*
H7B0.82240.44900.02370.090*
H7C0.73070.33080.00910.090*
C80.8112 (3)0.4183 (4)0.1746 (3)0.0705 (10)
H8A0.73640.40780.17110.106*
H8B0.82900.52510.15820.106*
H8C0.84110.39350.24160.106*
C90.4617 (2)0.2110 (3)0.00971 (19)0.0380 (7)
C100.47112 (19)0.0524 (3)0.02548 (18)0.0361 (7)
C110.5739 (2)0.0028 (3)0.11235 (19)0.0386 (7)
C120.6346 (2)0.1106 (3)0.1700 (2)0.0460 (8)
H12A0.70830.10230.14630.055*
H12B0.62670.08160.24080.055*
C130.3987 (2)0.3244 (3)0.0462 (2)0.0443 (7)
H13A0.32670.32350.01620.053*
H13B0.42610.43060.03940.053*
C140.4010 (2)0.2827 (3)0.1591 (2)0.0448 (8)
C150.5115 (3)0.3042 (4)0.2106 (2)0.0646 (10)
H15A0.53260.41270.20470.097*
H15B0.55900.23680.17900.097*
H15C0.51240.27670.28070.097*
C160.3261 (3)0.3920 (4)0.2079 (2)0.0652 (10)
H16A0.32670.36630.27820.098*
H16B0.25660.37880.17540.098*
H16C0.34800.50000.20100.098*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0418 (15)0.0440 (15)0.0675 (17)0.0085 (12)0.0070 (13)0.0044 (13)
N20.0442 (14)0.0409 (15)0.0702 (17)0.0060 (12)0.0122 (12)0.0011 (13)
N30.0583 (16)0.0392 (14)0.0445 (14)0.0001 (12)0.0117 (12)0.0062 (11)
N40.0593 (16)0.0392 (15)0.0442 (14)0.0027 (12)0.0133 (12)0.0036 (11)
C10.0385 (16)0.0370 (17)0.0416 (16)0.0029 (13)0.0025 (13)0.0016 (13)
C20.0322 (15)0.0314 (15)0.0402 (16)0.0019 (11)0.0026 (12)0.0033 (11)
C30.0413 (16)0.0387 (17)0.0424 (16)0.0017 (14)0.0045 (13)0.0057 (13)
C40.0490 (18)0.050 (2)0.0595 (19)0.0021 (15)0.0164 (15)0.0029 (15)
C50.0491 (18)0.0458 (18)0.0488 (17)0.0039 (15)0.0014 (14)0.0070 (14)
C60.0457 (17)0.0406 (17)0.0507 (17)0.0024 (14)0.0067 (14)0.0028 (14)
C70.055 (2)0.052 (2)0.071 (2)0.0062 (16)0.0062 (16)0.0042 (17)
C80.068 (2)0.061 (2)0.084 (3)0.0038 (19)0.0189 (19)0.0165 (19)
C90.0411 (16)0.0354 (17)0.0370 (15)0.0034 (13)0.0004 (12)0.0020 (13)
C100.0367 (15)0.0380 (17)0.0331 (15)0.0046 (12)0.0008 (11)0.0016 (11)
C110.0412 (16)0.0380 (17)0.0366 (15)0.0045 (13)0.0033 (12)0.0039 (13)
C120.0470 (17)0.0492 (19)0.0429 (16)0.0018 (14)0.0091 (13)0.0031 (14)
C130.0459 (17)0.0349 (16)0.0518 (17)0.0025 (13)0.0030 (13)0.0026 (14)
C140.0489 (18)0.0416 (18)0.0438 (16)0.0031 (14)0.0053 (14)0.0027 (13)
C150.064 (2)0.061 (2)0.065 (2)0.0014 (18)0.0099 (17)0.0108 (18)
C160.081 (2)0.060 (2)0.057 (2)0.0161 (19)0.0187 (18)0.0003 (17)
Geometric parameters (Å, º) top
N1—C11.322 (3)C8—H8A0.9600
N1—N21.386 (3)C8—H8B0.9600
N2—C31.311 (3)C8—H8C0.9600
N3—C91.312 (3)C9—C101.420 (4)
N3—N41.382 (3)C9—C131.495 (4)
N4—C111.323 (4)C10—C10ii1.373 (5)
C1—C21.413 (3)C10—C11ii1.419 (3)
C1—C51.482 (4)C11—C10ii1.419 (3)
C2—C2i1.371 (5)C11—C121.491 (4)
C2—C3i1.423 (3)C12—C14ii1.534 (4)
C3—C2i1.423 (3)C12—H12A0.9700
C3—C41.485 (4)C12—H12B0.9700
C4—C6i1.533 (4)C13—C141.541 (4)
C4—H4A0.9700C13—H13A0.9700
C4—H4B0.9700C13—H13B0.9700
C5—C61.540 (4)C14—C161.521 (4)
C5—H5A0.9700C14—C151.525 (4)
C5—H5B0.9700C14—C12ii1.534 (4)
C6—C81.524 (4)C15—H15A0.9600
C6—C71.525 (4)C15—H15B0.9600
C6—C4i1.533 (4)C15—H15C0.9600
C7—H7A0.9600C16—H16A0.9600
C7—H7B0.9600C16—H16B0.9600
C7—H7C0.9600C16—H16C0.9600
C1—N1—N2120.5 (2)H8A—C8—H8C109.5
C3—N2—N1120.4 (2)H8B—C8—H8C109.5
C9—N3—N4120.4 (2)N3—C9—C10121.3 (2)
C11—N4—N3120.6 (2)N3—C9—C13120.5 (2)
N1—C1—C2121.0 (2)C10—C9—C13118.2 (2)
N1—C1—C5120.4 (2)C10ii—C10—C11ii118.1 (3)
C2—C1—C5118.6 (2)C10ii—C10—C9118.5 (3)
C2i—C2—C1118.5 (3)C11ii—C10—C9123.4 (2)
C2i—C2—C3i118.3 (3)N4—C11—C10ii121.0 (2)
C1—C2—C3i123.2 (2)N4—C11—C12120.2 (2)
N2—C3—C2i121.2 (2)C10ii—C11—C12118.8 (2)
N2—C3—C4120.5 (2)C11—C12—C14ii112.6 (2)
C2i—C3—C4118.2 (2)C11—C12—H12A109.1
C3—C4—C6i113.0 (2)C14ii—C12—H12A109.1
C3—C4—H4A109.0C11—C12—H12B109.1
C6i—C4—H4A109.0C14ii—C12—H12B109.1
C3—C4—H4B109.0H12A—C12—H12B107.8
C6i—C4—H4B109.0C9—C13—C14112.2 (2)
H4A—C4—H4B107.8C9—C13—H13A109.2
C1—C5—C6113.1 (2)C14—C13—H13A109.2
C1—C5—H5A109.0C9—C13—H13B109.2
C6—C5—H5A109.0C14—C13—H13B109.2
C1—C5—H5B109.0H13A—C13—H13B107.9
C6—C5—H5B109.0C16—C14—C15109.4 (3)
H5A—C5—H5B107.8C16—C14—C12ii109.2 (2)
C8—C6—C7109.5 (3)C15—C14—C12ii110.0 (2)
C8—C6—C4i109.7 (2)C16—C14—C13108.9 (2)
C7—C6—C4i110.0 (2)C15—C14—C13110.0 (2)
C8—C6—C5109.0 (2)C12ii—C14—C13109.3 (2)
C7—C6—C5110.1 (2)C14—C15—H15A109.5
C4i—C6—C5108.6 (2)C14—C15—H15B109.5
C6—C7—H7A109.5H15A—C15—H15B109.5
C6—C7—H7B109.5C14—C15—H15C109.5
H7A—C7—H7B109.5H15A—C15—H15C109.5
C6—C7—H7C109.5H15B—C15—H15C109.5
H7A—C7—H7C109.5C14—C16—H16A109.5
H7B—C7—H7C109.5C14—C16—H16B109.5
C6—C8—H8A109.5H16A—C16—H16B109.5
C6—C8—H8B109.5C14—C16—H16C109.5
H8A—C8—H8B109.5H16A—C16—H16C109.5
C6—C8—H8C109.5H16B—C16—H16C109.5
Symmetry codes: (i) x+2, y, z; (ii) x+1, y, z.

Experimental details

Crystal data
Chemical formulaC16H20N4
Mr268.36
Crystal system, space groupMonoclinic, P21/n
Temperature (K)298
a, b, c (Å)12.819 (4), 8.441 (3), 13.310 (4)
β (°) 95.462 (5)
V3)1433.7 (8)
Z4
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.33 × 0.28 × 0.21
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 1998)
Tmin, Tmax0.975, 0.984
No. of measured, independent and
observed [I > 2σ(I)] reflections
7218, 2518, 1416
Rint0.048
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.052, 0.179, 1.04
No. of reflections2518
No. of parameters185
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.18, 0.20

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

 

Acknowledgements

We thank the Natural Science Foundation of the China (No. 20672090) and the Natural Science Foundation of Jiangsu Province (No. BK2006033) for support.

References

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