1,2,3,4-Tetra-hydro-phenazine 5,10-dioxide.

The complete mol-ecule of the title compound, C(12)H(12)N(2)O(2), lies on two crystallographic symmetry elements: a twofold axis and a mirror plane. In the mol-ecular structure, the quinoxaline ring and two methyl-ene substituents lie on the mirror plane while the other two methyl-ene groups are disordered about the plane. The crystal packing is stabilized by weak inter-molecular π-π stacking inter-actions with centroid-centroid distances of 3.6803 (7) Å.

Related literature

For the synthetic preparation, see: Haddadin & Issidorides (1965 ▶); Issidorides & Haddadin (1966 ▶). For background to quinoxaline di-N-oxide compounds, see: Edwards et al. (1975 ▶) and for their biological activity, see: Urquiola et al. (2008 ▶). For a related structure, see: Wang et al. (2010 ▶).

Experimental

Crystal data

C12H12N2O2

M = 216.24

Orthorhombic,

a = 11.7780 (2) Å

b = 13.1938 (3) Å

c = 6.5561 (1) Å

V = 1018.80 (3) Å3

Z = 4

Mo Kα radiation

μ = 0.10 mm−1

T = 296 K

0.31 × 0.29 × 0.26 mm

Data collection

Bruker APEXII CCD area-detector diffractometer

Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ▶) T min = 0.67, T max = 0.74

3311 measured reflections

620 independent reflections

534 reflections with I > 2σ(I)

R int = 0.016

Refinement

R[F 2 > 2σ(F 2)] = 0.040

wR(F 2) = 0.127

S = 1.10

620 reflections

61 parameters

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.23 e Å−3

Δρmin = −0.29 e Å−3

Data collection: APEX2 (Bruker, 2007 ▶); cell refinement: SAINT (Bruker, 2007 ▶); data reduction: SAINT; program(s) used to solve structure: SIR97 (Altomare et al., 1999 ▶); program(s) used to refine structure: SHELXTL (Sheldrick, 2008 ▶); molecular graphics: SHELXTL; software used to prepare material for publication: WinGX (Farrugia, 1999 ▶).

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810030242/nk2042sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810030242/nk2042Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

C12H12N2O2	F(000) = 456
Mr = 216.24	Dx = 1.410 Mg m−3
Orthorhombic, Cmcm	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2c 2	Cell parameters from 1577 reflections
a = 11.7780 (2) Å	θ = 2.3–26.8°
b = 13.1938 (3) Å	µ = 0.10 mm−1
c = 6.5561 (1) Å	T = 296 K
V = 1018.80 (3) Å3	Prism, yellow
Z = 4	0.31 × 0.29 × 0.26 mm

Bruker APEXII CCD area-detector diffractometer	620 independent reflections
Radiation source: fine-focus sealed tube	534 reflections with I > 2σ(I)
graphite	Rint = 0.016
φ and ω scans	θmax = 26.9°, θmin = 2.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −14→14
Tmin = 0.67, Tmax = 0.74	k = −16→12
3311 measured reflections	l = −8→8

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)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.127	H atoms treated by a mixture of independent and constrained refinement
S = 1.10	w = 1/[σ2(Fo2) + (0.0854P)2 + 0.1004P] where P = (Fo2 + 2Fc2)/3
620 reflections	(Δ/σ)max < 0.001
61 parameters	Δρmax = 0.23 e Å−3
0 restraints	Δρmin = −0.29 e Å−3

Experimental. 1H NMR (400?MHz, DMSO-d6): δ 8.67 (2H, d, J = 3.5?Hz, Ar—H), 7.89 (2H, d, J = 3.2?Hz, Ar—H), 3.77 (1H, s, CH), 2.66 (3H, s, CH3), 2.51 (2H, m, CH2), 1.45 (6H, s, CH3); Calcd for C13H16N2O2: C, 67.22; H, 6.94; N, 12.06. Found: C, 67.18; H, 6.99; N, 11.95; ESIMS calcd for C13H16N2O2H+ m/z 232.38, found m/z 232.19.

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	Occ. (<1)
C1	0.44078 (13)	−0.14330 (10)	0.2500	0.0434 (4)
H1	0.4017	−0.2045	0.2500	0.052*
C2	0.38142 (12)	−0.05388 (9)	0.2500	0.0399 (4)
H2	0.3025	−0.0544	0.2500	0.048*
C3	0.44062 (11)	0.03818 (9)	0.2500	0.0311 (4)
C4	0.44068 (10)	0.21722 (9)	0.2500	0.0326 (4)
C5	0.37292 (12)	0.31337 (10)	0.2500	0.0470 (4)
H5	0.3247 (10)	0.3113 (9)	0.131 (2)	0.070*
C6	0.44666 (19)	0.40485 (17)	0.1867 (4)	0.0618 (9)	0.50
H6	0.407 (2)	0.4669 (19)	0.199 (5)	0.090*	0.50
H7	0.468 (3)	0.3993 (19)	0.040 (4)	0.090*	0.50
N1	0.38161 (10)	0.12976 (7)	0.2500	0.0336 (4)
O1	0.27161 (9)	0.12938 (6)	0.2500	0.0508 (4)

	U11	U22	U33	U12	U13	U23
C1	0.0608 (9)	0.0288 (7)	0.0407 (7)	−0.0082 (5)	0.000	0.000
C2	0.0426 (8)	0.0339 (7)	0.0432 (7)	−0.0078 (5)	0.000	0.000
C3	0.0339 (8)	0.0281 (7)	0.0314 (6)	−0.0008 (4)	0.000	0.000
C4	0.0318 (7)	0.0277 (7)	0.0384 (7)	0.0008 (4)	0.000	0.000
C5	0.0372 (8)	0.0320 (8)	0.0719 (10)	0.0056 (5)	0.000	0.000
C6	0.0516 (11)	0.0289 (10)	0.105 (3)	0.0038 (7)	0.0002 (10)	0.0110 (10)
N1	0.0282 (6)	0.0313 (6)	0.0412 (6)	−0.0005 (3)	0.000	0.000
O1	0.0269 (6)	0.0447 (7)	0.0807 (8)	−0.0011 (3)	0.000	0.000

C1—C2	1.3714 (19)	C5—C6ii	1.544 (3)
C1—C1i	1.395 (3)	C5—C6	1.544 (3)
C1—H1	0.9300	C5—H5	0.965 (13)
C2—C3	1.4005 (17)	C6—C6ii	0.831 (5)
C2—H2	0.9300	C6—C6iii	1.256 (5)
C3—N1	1.3939 (15)	C6—C6i	1.506 (4)
C3—C3i	1.399 (2)	C6—H6	0.95 (2)
C4—N1	1.3474 (15)	C6—H7	1.00 (3)
C4—C4i	1.397 (2)	N1—O1	1.2956 (16)
C4—C5	1.4987 (16)
C2—C1—C1i	120.65 (9)	C6ii—C6—C6iii	90.000 (2)
C2—C1—H1	119.7	C6ii—C6—C6i	56.5 (2)
C1i—C1—H1	119.7	C6iii—C6—C6i	33.5 (2)
C1—C2—C3	119.49 (15)	C6ii—C6—C5	74.39 (10)
C1—C2—H2	120.3	C6iii—C6—C5	124.23 (10)
C3—C2—H2	120.3	C6i—C6—C5	108.72 (16)
N1—C3—C3i	119.90 (7)	C6ii—C6—H6	85.1 (18)
N1—C3—C2	120.24 (14)	C6iii—C6—H6	119.6 (16)
C3i—C3—C2	119.86 (8)	C6i—C6—H6	111.4 (17)
N1—C4—C4i	121.08 (7)	C5—C6—H6	112.1 (16)
N1—C4—C5	116.74 (12)	C6ii—C6—H7	164.4 (18)
C4i—C4—C5	122.17 (7)	C6iii—C6—H7	75.0 (18)
C4—C5—C6ii	111.23 (14)	C6i—C6—H7	108.4 (18)
C4—C5—C6	111.23 (14)	C5—C6—H7	110.3 (16)
C6ii—C5—C6	31.2 (2)	H6—C6—H7	106 (2)
C4—C5—H5	106.8 (7)	O1—N1—C4	121.31 (9)
C6ii—C5—H5	124.8 (8)	O1—N1—C3	119.68 (9)
C6—C5—H5	97.8 (7)	C4—N1—C3	119.01 (13)
C1i—C1—C2—C3	0.0	C4—C5—C6—C6i	−50.6 (2)
C1—C2—C3—N1	180.0	C6ii—C5—C6—C6i	45.6 (2)
C1—C2—C3—C3i	0.0	C4i—C4—N1—O1	180.0
N1—C4—C5—C6ii	163.23 (11)	C5—C4—N1—O1	0.0
C4i—C4—C5—C6ii	−16.77 (11)	C4i—C4—N1—C3	0.0
N1—C4—C5—C6	−163.23 (11)	C5—C4—N1—C3	180.0
C4i—C4—C5—C6	16.77 (11)	C3i—C3—N1—O1	180.0
C4—C5—C6—C6ii	−96.23 (6)	C2—C3—N1—O1	0.0
C4—C5—C6—C6iii	−17.19 (11)	C3i—C3—N1—C4	0.0
C6ii—C5—C6—C6iii	79.04 (8)	C2—C3—N1—C4	180.0