4-(4-Bromo-phen-yl)-7,7-dimethyl-2-methyl-amino-3-nitro-7,8-di-hydro-4H-chromen-5(6H)-one including an unknown solvate.

In the title compound, C18H19BrN2O4, the chromene unit is not quite planar (r.m.s. deviation = 0.199 Å), with the methyl C atoms lying 0.027 (4) and 1.929 (4) Å from the mean plane of the chromene unit. The six-membered carbocyclic ring of the chromene moiety adopts an envelope conformation, with the dimethyl-substituted C atom as the flap. The methyl-amine and nitro groups are slightly twisted from the chromene moiety, with C-N-C-O and O-N-C-C torsion angles of 2.7 (4) and -0.4 (4)°, respectively. The dihedral angle between the mean plane of the chromene unit and the benzene ring is 85.61 (13)°. An intra-molecular N-H⋯O hydrogen bond generates an S(6) ring motif, which stabilizes the mol-ecular conformation. In the crystal, mol-ecules are linked via N-H⋯O hydrogen bonds, forming hexa-gonal rings lying parallel to the ab plane. A region of disordered electron density, most probably disordered ethanol solvent mol-ecules, occupying voids of ca 432 Å(3) for an electron count of 158, was treated using the SQUEEZE routine in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148-155]. Their formula mass and unit-cell characteristics were not taken into account during refinement.

Related literature

For the biological and pharmacological properties of chromene and chromene derivatives, see: Thomas & Zachariah (2013 ▶). For graph-set notation, see: Bernstein et al. (1995 ▶). For ring puckering parameters, see: Cremer & Pople (1975 ▶). For a related structure, see: Narayanan et al. (2013 ▶).

Experimental

Crystal data

C18H19BrN2O4

M = 407.26

Trigonal,

a = 24.2105 (13) Å

c = 15.7745 (9) Å

V = 8007.4 (8) Å3

Z = 18

Mo Kα radiation

μ = 2.34 mm−1

T = 293 K

0.35 × 0.30 × 0.30 mm

Data collection

Bruker Kappa APEXII CCD diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2008 ▶) T min = 0.446, T max = 0.496

25281 measured reflections

3206 independent reflections

2565 reflections with I > 2σ(I)

R int = 0.035

Refinement

R[F 2 > 2σ(F 2)] = 0.038

wR(F 2) = 0.105

S = 1.09

3206 reflections

233 parameters

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.68 e Å−3

Δρmin = −0.61 e Å−3

Data collection: APEX2 (Bruker, 2008 ▶); cell refinement: SAINT (Bruker, 2008 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: PLATON (Spek, 2009 ▶) and Mercury (Macrae et al., 2008 ▶); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009 ▶).

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536814007983/su2714sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536814007983/su2714Isup2.hkl

Click here for additional data file.

Supporting information file. DOI: 10.1107/S1600536814007983/su2714Isup3.cml

CCDC reference: 996468

Additional supporting information: crystallographic information; 3D view; checkCIF report

C18H19BrN2O4	Dx = 1.520 Mg m−3
Mr = 407.26	Mo Kα radiation, λ = 0.71073 Å
Trigonal, R3	Cell parameters from 3206 reflections
Hall symbol: -R 3	θ = 2.3–25.2°
a = 24.2105 (13) Å	µ = 2.34 mm−1
c = 15.7745 (9) Å	T = 293 K
V = 8007.4 (8) Å3	Block, colourless
Z = 18	0.35 × 0.30 × 0.30 mm
F(000) = 3744

Bruker Kappa APEXII CCD diffractometer	3206 independent reflections
Radiation source: fine-focus sealed tube	2565 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.035
ω and φ scan	θmax = 25.2°, θmin = 2.3°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −28→29
Tmin = 0.446, Tmax = 0.496	k = −29→28
25281 measured reflections	l = −12→18

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)] = 0.038	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.105	H atoms treated by a mixture of independent and constrained refinement
S = 1.09	w = 1/[σ2(Fo2) + (0.0569P)2 + 9.8133P] where P = (Fo2 + 2Fc2)/3
3206 reflections	(Δ/σ)max < 0.001
233 parameters	Δρmax = 0.68 e Å−3
0 restraints	Δρmin = −0.61 e Å−3

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
Br1	0.212132 (19)	0.139268 (18)	0.68871 (2)	0.06222 (17)
O1	0.43022 (10)	0.17889 (10)	0.40027 (13)	0.0472 (5)
O2	0.26619 (8)	0.05160 (8)	0.21543 (11)	0.0321 (4)
O3	0.42426 (10)	0.09139 (10)	0.35374 (13)	0.0447 (5)
O4	0.27248 (10)	0.24234 (10)	0.29435 (14)	0.0504 (5)
N1	0.40219 (10)	0.12873 (11)	0.35810 (13)	0.0354 (5)
N2	0.32782 (12)	0.01391 (11)	0.25833 (16)	0.0374 (6)
H2N	0.3582 (17)	0.0173 (16)	0.287 (2)	0.056 (10)*
C1	0.24640 (15)	0.14478 (14)	0.57850 (17)	0.0399 (7)
C2	0.30235 (15)	0.19826 (14)	0.55683 (18)	0.0439 (7)
H2	0.3238	0.2310	0.5958	0.053*
C3	0.32632 (14)	0.20269 (13)	0.47641 (17)	0.0390 (7)
H3	0.3643	0.2389	0.4613	0.047*
C4	0.29519 (12)	0.15445 (12)	0.41766 (16)	0.0301 (6)
C5	0.23957 (13)	0.10049 (13)	0.44189 (18)	0.0397 (7)
H5	0.2186	0.0672	0.4035	0.048*
C6	0.21442 (15)	0.09504 (15)	0.52256 (19)	0.0455 (7)
H6	0.1769	0.0587	0.5384	0.055*
C7	0.32208 (12)	0.16060 (12)	0.32833 (15)	0.0293 (6)
H7A	0.3573	0.2044	0.3209	0.035*
C8	0.34739 (12)	0.11581 (12)	0.31480 (15)	0.0297 (6)
C9	0.31590 (12)	0.06113 (12)	0.26513 (16)	0.0297 (6)
C10	0.24637 (12)	0.09617 (12)	0.21277 (15)	0.0278 (6)
C11	0.27201 (11)	0.14784 (12)	0.26209 (15)	0.0281 (5)
C12	0.24891 (12)	0.19332 (12)	0.25304 (16)	0.0313 (6)
C13	0.19699 (12)	0.17837 (12)	0.18972 (17)	0.0336 (6)
H13A	0.2165	0.1994	0.1367	0.040*
H13B	0.1714	0.1963	0.2099	0.040*
C14	0.15270 (12)	0.10710 (13)	0.17229 (17)	0.0335 (6)
C15	0.19391 (12)	0.07738 (13)	0.15019 (17)	0.0321 (6)
H15A	0.1674	0.0313	0.1494	0.039*
H15B	0.2119	0.0912	0.0940	0.039*
C16	0.10934 (15)	0.09891 (16)	0.0969 (2)	0.0502 (8)
H16A	0.0811	0.0543	0.0866	0.075*
H16B	0.1350	0.1182	0.0475	0.075*
H16C	0.0848	0.1191	0.1095	0.075*
C17	0.11220 (14)	0.07477 (14)	0.2504 (2)	0.0458 (7)
H17A	0.0850	0.0301	0.2393	0.069*
H17B	0.0866	0.0937	0.2636	0.069*
H17C	0.1395	0.0802	0.2976	0.069*
C18	0.29496 (15)	−0.04065 (14)	0.2025 (2)	0.0477 (8)
H18A	0.3047	−0.0730	0.2189	0.072*
H18B	0.3086	−0.0278	0.1452	0.072*
H18C	0.2498	−0.0573	0.2066	0.072*

	U11	U22	U33	U12	U13	U23
Br1	0.0846 (3)	0.0630 (3)	0.0458 (2)	0.0419 (2)	0.02115 (17)	0.00610 (15)
O1	0.0358 (11)	0.0452 (13)	0.0568 (13)	0.0174 (10)	−0.0149 (10)	−0.0151 (10)
O2	0.0316 (10)	0.0282 (10)	0.0418 (10)	0.0190 (8)	−0.0093 (8)	−0.0064 (8)
O3	0.0418 (12)	0.0528 (13)	0.0520 (12)	0.0330 (11)	−0.0116 (9)	−0.0050 (10)
O4	0.0536 (13)	0.0335 (12)	0.0689 (14)	0.0254 (10)	−0.0152 (11)	−0.0155 (10)
N1	0.0303 (12)	0.0409 (14)	0.0338 (12)	0.0169 (12)	−0.0007 (10)	0.0019 (10)
N2	0.0382 (14)	0.0366 (14)	0.0460 (13)	0.0254 (12)	−0.0108 (11)	−0.0049 (11)
C1	0.0492 (18)	0.0427 (17)	0.0363 (14)	0.0294 (15)	0.0069 (13)	0.0028 (12)
C2	0.0535 (19)	0.0352 (16)	0.0377 (15)	0.0183 (15)	−0.0045 (14)	−0.0096 (12)
C3	0.0381 (16)	0.0269 (15)	0.0414 (15)	0.0082 (13)	−0.0028 (12)	−0.0038 (11)
C4	0.0296 (14)	0.0278 (14)	0.0359 (13)	0.0168 (12)	−0.0028 (11)	−0.0024 (11)
C5	0.0357 (16)	0.0311 (15)	0.0422 (15)	0.0091 (13)	−0.0017 (12)	−0.0066 (12)
C6	0.0372 (17)	0.0399 (17)	0.0494 (17)	0.0119 (14)	0.0076 (13)	0.0037 (14)
C7	0.0261 (13)	0.0250 (13)	0.0344 (13)	0.0109 (11)	−0.0002 (10)	−0.0011 (11)
C8	0.0241 (13)	0.0335 (14)	0.0315 (13)	0.0143 (12)	−0.0012 (10)	0.0003 (11)
C9	0.0244 (13)	0.0325 (14)	0.0337 (13)	0.0153 (12)	0.0009 (10)	0.0022 (11)
C10	0.0259 (13)	0.0253 (13)	0.0345 (13)	0.0145 (11)	0.0022 (10)	0.0019 (10)
C11	0.0238 (13)	0.0261 (14)	0.0343 (13)	0.0125 (11)	0.0019 (10)	0.0011 (11)
C12	0.0302 (14)	0.0252 (14)	0.0386 (14)	0.0140 (12)	0.0026 (11)	−0.0001 (11)
C13	0.0338 (15)	0.0304 (14)	0.0423 (15)	0.0203 (13)	0.0041 (12)	0.0037 (12)
C14	0.0286 (14)	0.0297 (14)	0.0445 (15)	0.0164 (12)	−0.0025 (12)	0.0002 (11)
C15	0.0308 (14)	0.0314 (14)	0.0371 (14)	0.0177 (12)	−0.0062 (11)	−0.0057 (11)
C16	0.0410 (17)	0.0495 (19)	0.067 (2)	0.0275 (16)	−0.0180 (15)	−0.0085 (16)
C17	0.0321 (16)	0.0385 (17)	0.0652 (19)	0.0164 (14)	0.0095 (14)	0.0054 (14)
C18	0.0516 (19)	0.0396 (17)	0.0617 (19)	0.0302 (16)	−0.0143 (15)	−0.0141 (15)

Br1—C1	1.902 (3)	C7—H7A	0.9800
O1—N1	1.247 (3)	C8—C9	1.392 (4)
O2—C9	1.356 (3)	C10—C11	1.334 (3)
O2—C10	1.384 (3)	C10—C15	1.489 (3)
O3—N1	1.261 (3)	C11—C12	1.470 (4)
O4—C12	1.217 (3)	C12—C13	1.501 (4)
N1—C8	1.382 (3)	C13—C14	1.534 (4)
N2—C9	1.316 (3)	C13—H13A	0.9700
N2—C18	1.450 (4)	C13—H13B	0.9700
N2—H2N	0.83 (3)	C14—C17	1.525 (4)
C1—C2	1.369 (4)	C14—C16	1.532 (4)
C1—C6	1.377 (4)	C14—C15	1.534 (4)
C2—C3	1.377 (4)	C15—H15A	0.9700
C2—H2	0.9300	C15—H15B	0.9700
C3—C4	1.382 (4)	C16—H16A	0.9600
C3—H3	0.9300	C16—H16B	0.9600
C4—C5	1.381 (4)	C16—H16C	0.9600
C4—C7	1.528 (3)	C17—H17A	0.9600
C5—C6	1.388 (4)	C17—H17B	0.9600
C5—H5	0.9300	C17—H17C	0.9600
C6—H6	0.9300	C18—H18A	0.9600
C7—C8	1.504 (4)	C18—H18B	0.9600
C7—C11	1.511 (3)	C18—H18C	0.9600
C9—O2—C10	120.62 (19)	C10—C11—C7	123.0 (2)
O1—N1—O3	120.5 (2)	C12—C11—C7	118.7 (2)
O1—N1—C8	118.5 (2)	O4—C12—C11	120.7 (2)
O3—N1—C8	120.9 (2)	O4—C12—C13	121.3 (2)
C9—N2—C18	125.6 (2)	C11—C12—C13	118.1 (2)
C9—N2—H2N	116 (2)	C12—C13—C14	114.9 (2)
C18—N2—H2N	119 (2)	C12—C13—H13A	108.6
C2—C1—C6	121.7 (3)	C14—C13—H13A	108.6
C2—C1—Br1	119.0 (2)	C12—C13—H13B	108.6
C6—C1—Br1	119.3 (2)	C14—C13—H13B	108.6
C1—C2—C3	118.9 (3)	H13A—C13—H13B	107.5
C1—C2—H2	120.6	C17—C14—C16	109.7 (2)
C3—C2—H2	120.6	C17—C14—C15	110.2 (2)
C2—C3—C4	121.4 (3)	C16—C14—C15	109.1 (2)
C2—C3—H3	119.3	C17—C14—C13	109.9 (2)
C4—C3—H3	119.3	C16—C14—C13	109.5 (2)
C5—C4—C3	118.4 (2)	C15—C14—C13	108.4 (2)
C5—C4—C7	120.9 (2)	C10—C15—C14	111.2 (2)
C3—C4—C7	120.7 (2)	C10—C15—H15A	109.4
C4—C5—C6	121.2 (3)	C14—C15—H15A	109.4
C4—C5—H5	119.4	C10—C15—H15B	109.4
C6—C5—H5	119.4	C14—C15—H15B	109.4
C1—C6—C5	118.4 (3)	H15A—C15—H15B	108.0
C1—C6—H6	120.8	C14—C16—H16A	109.5
C5—C6—H6	120.8	C14—C16—H16B	109.5
C8—C7—C11	109.2 (2)	H16A—C16—H16B	109.5
C8—C7—C4	111.6 (2)	C14—C16—H16C	109.5
C11—C7—C4	111.0 (2)	H16A—C16—H16C	109.5
C8—C7—H7A	108.3	H16B—C16—H16C	109.5
C11—C7—H7A	108.3	C14—C17—H17A	109.5
C4—C7—H7A	108.3	C14—C17—H17B	109.5
N1—C8—C9	120.0 (2)	H17A—C17—H17B	109.5
N1—C8—C7	117.3 (2)	C14—C17—H17C	109.5
C9—C8—C7	122.6 (2)	H17A—C17—H17C	109.5
N2—C9—O2	111.5 (2)	H17B—C17—H17C	109.5
N2—C9—C8	128.2 (2)	N2—C18—H18A	109.5
O2—C9—C8	120.3 (2)	N2—C18—H18B	109.5
C11—C10—O2	122.2 (2)	H18A—C18—H18B	109.5
C11—C10—C15	126.8 (2)	N2—C18—H18C	109.5
O2—C10—C15	110.9 (2)	H18A—C18—H18C	109.5
C10—C11—C12	118.2 (2)	H18B—C18—H18C	109.5
C6—C1—C2—C3	1.3 (5)	C7—C8—C9—N2	−169.2 (3)
Br1—C1—C2—C3	−178.6 (2)	N1—C8—C9—O2	−172.9 (2)
C1—C2—C3—C4	−0.1 (5)	C7—C8—C9—O2	11.0 (4)
C2—C3—C4—C5	−1.3 (4)	C9—O2—C10—C11	−4.3 (4)
C2—C3—C4—C7	179.2 (3)	C9—O2—C10—C15	176.5 (2)
C3—C4—C5—C6	1.5 (4)	O2—C10—C11—C12	178.4 (2)
C7—C4—C5—C6	−179.0 (3)	C15—C10—C11—C12	−2.6 (4)
C2—C1—C6—C5	−1.2 (5)	O2—C10—C11—C7	−3.5 (4)
Br1—C1—C6—C5	178.8 (2)	C15—C10—C11—C7	175.5 (2)
C4—C5—C6—C1	−0.3 (5)	C8—C7—C11—C10	12.9 (3)
C5—C4—C7—C8	−69.8 (3)	C4—C7—C11—C10	−110.6 (3)
C3—C4—C7—C8	109.7 (3)	C8—C7—C11—C12	−169.0 (2)
C5—C4—C7—C11	52.3 (3)	C4—C7—C11—C12	67.5 (3)
C3—C4—C7—C11	−128.2 (3)	C10—C11—C12—O4	−177.2 (3)
O1—N1—C8—C9	178.2 (2)	C7—C11—C12—O4	4.6 (4)
O3—N1—C8—C9	−0.4 (4)	C10—C11—C12—C13	1.0 (3)
O1—N1—C8—C7	−5.5 (3)	C7—C11—C12—C13	−177.2 (2)
O3—N1—C8—C7	176.0 (2)	O4—C12—C13—C14	−154.1 (3)
C11—C7—C8—N1	167.3 (2)	C11—C12—C13—C14	27.6 (3)
C4—C7—C8—N1	−69.6 (3)	C12—C13—C14—C17	68.6 (3)
C11—C7—C8—C9	−16.5 (3)	C12—C13—C14—C16	−170.8 (2)
C4—C7—C8—C9	106.6 (3)	C12—C13—C14—C15	−51.9 (3)
C18—N2—C9—O2	2.7 (4)	C11—C10—C15—C14	−23.9 (4)
C18—N2—C9—C8	−177.2 (3)	O2—C10—C15—C14	155.2 (2)
C10—O2—C9—N2	−179.4 (2)	C17—C14—C15—C10	−71.9 (3)
C10—O2—C9—C8	0.5 (3)	C16—C14—C15—C10	167.6 (2)
N1—C8—C9—N2	6.9 (4)	C13—C14—C15—C10	48.5 (3)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2N···O3	0.83 (3)	2.00 (3)	2.618 (3)	130 (3)
N2—H2N···O4i	0.83 (3)	2.38 (3)	2.969 (3)	129 (3)

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2N⋯O3	0.83 (3)	2.00 (3)	2.618 (3)	130 (3)
N2—H2N⋯O4i	0.83 (3)	2.38 (3)	2.969 (3)	129 (3)

Symmetry code: (i) .