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

Peng, J.-H.; Hao, W.-J.; Tu, S.-J.

doi:10.1107/S1600536808043912

organic compounds

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ISSN: 2056-9890

Volume 65| Part 2| February 2009| Page o238

doi:10.1107/S1600536808043912

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

Ju-Hua Peng,^a Wen-Juan Hao ^b and Shu-Jiang Tu ^b ^*

^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 ); Labovitz et al. (1990 ); Mizutani, Shiroshita, Okuda et al. (1989 ); Patterson (1992 ); Coghlan et al. (1989 ); Mizutani, Shiroshita, Sakaki et al. (1989 b); 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

Crystal data

C₁₆H₂₀N₄
M_r = 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 ) T_min = 0.975, T_max = 0.984
7218 measured reflections
2518 independent reflections
1416 reflections with I > 2σ(I)
R_int = 0.048

Refinement

R[F² > 2σ(F²)] = 0.052
wR(F²) = 0.179
S = 1.04
2518 reflections
185 parameters
H-atom parameters constrained
Δρ_max = 0.18 e Å⁻³
Δρ_min = −0.20 e Å⁻³

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

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808043912/hk2606sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808043912/hk2606Isup2.hkl

checkCIF report

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, Q_T, 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.

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

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

C₁₆H₂₀N₄	F(000) = 576
M_r = 268.36	D_x = 1.243 Mg m⁻³
Monoclinic, P2₁/n	Melting point = 562–563 K
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 12.819 (4) Å	Cell parameters from 1230 reflections
b = 8.441 (3) Å	θ = 2.3–23.2°
c = 13.310 (4) Å	µ = 0.08 mm⁻¹
β = 95.462 (5)°	T = 298 K
V = 1433.7 (8) Å³	Block, pale yellow
Z = 4	0.33 × 0.28 × 0.21 mm

Data collection top

Bruker SMART CCD area-detector diffractometer	2518 independent reflections
Radiation source: fine-focus sealed tube	1416 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.048
ϕ and ω scans	θ_max = 25.0°, θ_min = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 1998)	h = −15→15
T_min = 0.975, T_max = 0.984	k = −9→10
7218 measured reflections	l = −15→14

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)] = 0.052	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.179	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + 0.3048P] where P = (F_o² + 2F_c²)/3
2518 reflections	(Δ/σ)_max < 0.001
185 parameters	Δρ_max = 0.18 e Å⁻³
0 restraints	Δρ_min = −0.20 e Å⁻³

Crystal data top

C₁₆H₂₀N₄	V = 1433.7 (8) Å³
M_r = 268.36	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 12.819 (4) Å	µ = 0.08 mm⁻¹
b = 8.441 (3) Å	T = 298 K
c = 13.310 (4) Å	0.33 × 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)
T_min = 0.975, T_max = 0.984	R_int = 0.048
7218 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.052	0 restraints
wR(F²) = 0.179	H-atom parameters constrained
S = 1.04	Δρ_max = 0.18 e Å⁻³
2518 reflections	Δρ_min = −0.20 e Å⁻³
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

	x	y	z	U_iso*/U_eq
N1	1.11488 (18)	0.2369 (3)	0.00759 (19)	0.0510 (7)
N2	1.16426 (18)	0.1239 (3)	−0.04672 (19)	0.0513 (7)
N3	0.50653 (19)	0.2577 (3)	−0.08920 (17)	0.0469 (6)
N4	0.56253 (19)	0.1517 (3)	−0.14224 (17)	0.0470 (6)
C1	1.0250 (2)	0.2044 (3)	0.04438 (19)	0.0394 (7)
C2	0.97626 (18)	0.0553 (3)	0.02796 (18)	0.0350 (7)
C3	1.1205 (2)	−0.0146 (3)	−0.06568 (19)	0.0408 (7)
C4	1.1709 (2)	−0.1336 (3)	−0.1275 (2)	0.0522 (8)
H4A	1.2463	−0.1185	−0.1187	0.063*
H4B	1.1479	−0.1161	−0.1982	0.063*
C5	0.9742 (2)	0.3236 (4)	0.1053 (2)	0.0483 (8)
H5A	0.9906	0.4287	0.0819	0.058*
H5B	1.0030	0.3146	0.1752	0.058*
C6	0.8543 (2)	0.3047 (3)	0.0998 (2)	0.0456 (7)
C7	0.8054 (2)	0.3422 (4)	−0.0065 (2)	0.0602 (9)
H7A	0.8324	0.2704	−0.0536	0.090*
H7B	0.8224	0.4490	−0.0237	0.090*
H7C	0.7307	0.3308	−0.0091	0.090*
C8	0.8112 (3)	0.4183 (4)	0.1746 (3)	0.0705 (10)
H8A	0.7364	0.4078	0.1711	0.106*
H8B	0.8290	0.5251	0.1582	0.106*
H8C	0.8411	0.3935	0.2416	0.106*
C9	0.4617 (2)	0.2110 (3)	−0.00971 (19)	0.0380 (7)
C10	0.47112 (19)	0.0524 (3)	0.02548 (18)	0.0361 (7)
C11	0.5739 (2)	0.0028 (3)	−0.11235 (19)	0.0386 (7)
C12	0.6346 (2)	−0.1106 (3)	−0.1700 (2)	0.0460 (8)
H12A	0.7083	−0.1023	−0.1463	0.055*
H12B	0.6267	−0.0816	−0.2408	0.055*
C13	0.3987 (2)	0.3244 (3)	0.0462 (2)	0.0443 (7)
H13A	0.3267	0.3235	0.0162	0.053*
H13B	0.4261	0.4306	0.0394	0.053*
C14	0.4010 (2)	0.2827 (3)	0.1591 (2)	0.0448 (8)
C15	0.5115 (3)	0.3042 (4)	0.2106 (2)	0.0646 (10)
H15A	0.5326	0.4127	0.2047	0.097*
H15B	0.5590	0.2368	0.1790	0.097*
H15C	0.5124	0.2767	0.2807	0.097*
C16	0.3261 (3)	0.3920 (4)	0.2079 (2)	0.0652 (10)
H16A	0.3267	0.3663	0.2782	0.098*
H16B	0.2566	0.3788	0.1754	0.098*
H16C	0.3480	0.5000	0.2010	0.098*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0418 (15)	0.0440 (15)	0.0675 (17)	−0.0085 (12)	0.0070 (13)	−0.0044 (13)
N2	0.0442 (14)	0.0409 (15)	0.0702 (17)	−0.0060 (12)	0.0122 (12)	−0.0011 (13)
N3	0.0583 (16)	0.0392 (14)	0.0445 (14)	−0.0001 (12)	0.0117 (12)	0.0062 (11)
N4	0.0593 (16)	0.0392 (15)	0.0442 (14)	−0.0027 (12)	0.0133 (12)	0.0036 (11)
C1	0.0385 (16)	0.0370 (17)	0.0416 (16)	−0.0029 (13)	−0.0025 (13)	0.0016 (13)
C2	0.0322 (15)	0.0314 (15)	0.0402 (16)	−0.0019 (11)	−0.0026 (12)	0.0033 (11)
C3	0.0413 (16)	0.0387 (17)	0.0424 (16)	−0.0017 (14)	0.0045 (13)	0.0057 (13)
C4	0.0490 (18)	0.050 (2)	0.0595 (19)	0.0021 (15)	0.0164 (15)	0.0029 (15)
C5	0.0491 (18)	0.0458 (18)	0.0488 (17)	−0.0039 (15)	−0.0014 (14)	−0.0070 (14)
C6	0.0457 (17)	0.0406 (17)	0.0507 (17)	0.0024 (14)	0.0067 (14)	−0.0028 (14)
C7	0.055 (2)	0.052 (2)	0.071 (2)	0.0062 (16)	−0.0062 (16)	0.0042 (17)
C8	0.068 (2)	0.061 (2)	0.084 (3)	0.0038 (19)	0.0189 (19)	−0.0165 (19)
C9	0.0411 (16)	0.0354 (17)	0.0370 (15)	−0.0034 (13)	0.0004 (12)	0.0020 (13)
C10	0.0367 (15)	0.0380 (17)	0.0331 (15)	−0.0046 (12)	0.0008 (11)	0.0016 (11)
C11	0.0412 (16)	0.0380 (17)	0.0366 (15)	−0.0045 (13)	0.0033 (12)	0.0039 (13)
C12	0.0470 (17)	0.0492 (19)	0.0429 (16)	0.0018 (14)	0.0091 (13)	0.0031 (14)
C13	0.0459 (17)	0.0349 (16)	0.0518 (17)	−0.0025 (13)	0.0030 (13)	0.0026 (14)
C14	0.0489 (18)	0.0416 (18)	0.0438 (16)	0.0031 (14)	0.0053 (14)	−0.0027 (13)
C15	0.064 (2)	0.061 (2)	0.065 (2)	−0.0014 (18)	−0.0099 (17)	−0.0108 (18)
C16	0.081 (2)	0.060 (2)	0.057 (2)	0.0161 (19)	0.0187 (18)	−0.0003 (17)

Geometric parameters (Å, º) top

N1—C1	1.322 (3)	C8—H8A	0.9600
N1—N2	1.386 (3)	C8—H8B	0.9600
N2—C3	1.311 (3)	C8—H8C	0.9600
N3—C9	1.312 (3)	C9—C10	1.420 (4)
N3—N4	1.382 (3)	C9—C13	1.495 (4)
N4—C11	1.323 (4)	C10—C10ⁱⁱ	1.373 (5)
C1—C2	1.413 (3)	C10—C11ⁱⁱ	1.419 (3)
C1—C5	1.482 (4)	C11—C10ⁱⁱ	1.419 (3)
C2—C2ⁱ	1.371 (5)	C11—C12	1.491 (4)
C2—C3ⁱ	1.423 (3)	C12—C14ⁱⁱ	1.534 (4)
C3—C2ⁱ	1.423 (3)	C12—H12A	0.9700
C3—C4	1.485 (4)	C12—H12B	0.9700
C4—C6ⁱ	1.533 (4)	C13—C14	1.541 (4)
C4—H4A	0.9700	C13—H13A	0.9700
C4—H4B	0.9700	C13—H13B	0.9700
C5—C6	1.540 (4)	C14—C16	1.521 (4)
C5—H5A	0.9700	C14—C15	1.525 (4)
C5—H5B	0.9700	C14—C12ⁱⁱ	1.534 (4)
C6—C8	1.524 (4)	C15—H15A	0.9600
C6—C7	1.525 (4)	C15—H15B	0.9600
C6—C4ⁱ	1.533 (4)	C15—H15C	0.9600
C7—H7A	0.9600	C16—H16A	0.9600
C7—H7B	0.9600	C16—H16B	0.9600
C7—H7C	0.9600	C16—H16C	0.9600

C1—N1—N2	120.5 (2)	H8A—C8—H8C	109.5
C3—N2—N1	120.4 (2)	H8B—C8—H8C	109.5
C9—N3—N4	120.4 (2)	N3—C9—C10	121.3 (2)
C11—N4—N3	120.6 (2)	N3—C9—C13	120.5 (2)
N1—C1—C2	121.0 (2)	C10—C9—C13	118.2 (2)
N1—C1—C5	120.4 (2)	C10ⁱⁱ—C10—C11ⁱⁱ	118.1 (3)
C2—C1—C5	118.6 (2)	C10ⁱⁱ—C10—C9	118.5 (3)
C2ⁱ—C2—C1	118.5 (3)	C11ⁱⁱ—C10—C9	123.4 (2)
C2ⁱ—C2—C3ⁱ	118.3 (3)	N4—C11—C10ⁱⁱ	121.0 (2)
C1—C2—C3ⁱ	123.2 (2)	N4—C11—C12	120.2 (2)
N2—C3—C2ⁱ	121.2 (2)	C10ⁱⁱ—C11—C12	118.8 (2)
N2—C3—C4	120.5 (2)	C11—C12—C14ⁱⁱ	112.6 (2)
C2ⁱ—C3—C4	118.2 (2)	C11—C12—H12A	109.1
C3—C4—C6ⁱ	113.0 (2)	C14ⁱⁱ—C12—H12A	109.1
C3—C4—H4A	109.0	C11—C12—H12B	109.1
C6ⁱ—C4—H4A	109.0	C14ⁱⁱ—C12—H12B	109.1
C3—C4—H4B	109.0	H12A—C12—H12B	107.8
C6ⁱ—C4—H4B	109.0	C9—C13—C14	112.2 (2)
H4A—C4—H4B	107.8	C9—C13—H13A	109.2
C1—C5—C6	113.1 (2)	C14—C13—H13A	109.2
C1—C5—H5A	109.0	C9—C13—H13B	109.2
C6—C5—H5A	109.0	C14—C13—H13B	109.2
C1—C5—H5B	109.0	H13A—C13—H13B	107.9
C6—C5—H5B	109.0	C16—C14—C15	109.4 (3)
H5A—C5—H5B	107.8	C16—C14—C12ⁱⁱ	109.2 (2)
C8—C6—C7	109.5 (3)	C15—C14—C12ⁱⁱ	110.0 (2)
C8—C6—C4ⁱ	109.7 (2)	C16—C14—C13	108.9 (2)
C7—C6—C4ⁱ	110.0 (2)	C15—C14—C13	110.0 (2)
C8—C6—C5	109.0 (2)	C12ⁱⁱ—C14—C13	109.3 (2)
C7—C6—C5	110.1 (2)	C14—C15—H15A	109.5
C4ⁱ—C6—C5	108.6 (2)	C14—C15—H15B	109.5
C6—C7—H7A	109.5	H15A—C15—H15B	109.5
C6—C7—H7B	109.5	C14—C15—H15C	109.5
H7A—C7—H7B	109.5	H15A—C15—H15C	109.5
C6—C7—H7C	109.5	H15B—C15—H15C	109.5
H7A—C7—H7C	109.5	C14—C16—H16A	109.5
H7B—C7—H7C	109.5	C14—C16—H16B	109.5
C6—C8—H8A	109.5	H16A—C16—H16B	109.5
C6—C8—H8B	109.5	C14—C16—H16C	109.5
H8A—C8—H8B	109.5	H16A—C16—H16C	109.5
C6—C8—H8C	109.5	H16B—C16—H16C	109.5

Symmetry codes: (i) −x+2, −y, −z; (ii) −x+1, −y, −z.

Experimental details

Crystal data
Chemical formula	C₁₆H₂₀N₄
M_r	268.36
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	298
a, b, c (Å)	12.819 (4), 8.441 (3), 13.310 (4)
β (°)	95.462 (5)
V (Å³)	1433.7 (8)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.33 × 0.28 × 0.21

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 1998)
T_min, T_max	0.975, 0.984
No. of measured, independent and observed [I > 2σ(I)] reflections	7218, 2518, 1416
R_int	0.048
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.052, 0.179, 1.04
No. of reflections	2518
No. of parameters	185
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	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

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. CrossRef Web of Science Google Scholar
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