supplementary materials


rz5051 scheme

Acta Cryst. (2013). E69, o541    [ doi:10.1107/S1600536813006739 ]

Ethyl 4-(5-bromo-2-hydroxyphenyl)-2,7,7-trimethyl-5-oxo-1,4,5,6,7,8-hexahydroquinoline-3-carboxylate

M. M. Kurbanova, E. Z. Huseynov, A. V. Gurbanov, A. M. Maharramov and R. Kia

Abstract top

In the title compound, C21H24BrNO4, the dihedral angle between the heterocyclic ring and the pendant aromatic ring is 80.20 (13)°. The hexahydroquinone [i.e. the one with the C=O group] ring adopts a sofa conformation. An intramolecular O-H...O hydrogen bond generates an S(6) ring motif. The ethyl group is disordered over two sets of sites with a refined site occupancy ratio of 0.633 (10):0.366 (10). In the crystal, molecules are linked by N-H...O interactions, forming chains parallel to [101]. There are no significant C-H...[pi] or [pi]-[pi] interactions in the crystal structure.

Comment top

Hexahydroquinoline derivatives possess a variety of biological activities, such as vasodilatory, bronchodilatory, antiatherosclerotic, hepatoprotective, and antidiabetic activity (Sausins et al., 1988), and some of them have been used as calcium channel modulators and curatives for cardiovascular diseases (Nakayama et al., 1996). In past years, their uses as neuroprotectants, platelet anti-aggregatory agents, and cerebral anti-ischemic agents in the treatment of Alzheimer's disease and as chemosensitizers in tumor therapy have been also reported (Klusa, 1995).

The asymmetric unit of the title compound, Fig. 1, comprises a substituted hexahydroquinoline compound. Both six-membered rings of the hexahydroquinoline ring system adopt a half-boat conformation. Bond lengths (Allen et al., 1987) and angles are within normal ranges. An intramolecular O—H···O hydrogen bond generates an S(6) ring motif (Bernstein et al., 1995). In the crystal structure, molecules are linked together by intermolecular N—H···O hydrogen interactions (Table 1, Fig. 2) forming chains parallel to the [101] direction. The ethyl group is disordered over two sets of sites with a refined site occupancy ratio of 0.633 (10):0.366 (10). The compound contains one chiral center but the space group is centrosymmetric, so the molecule exists as a racemate.

Related literature top

For standard bond lengths, see: Allen et al. (1987). For hydrogen-bond motifs, see: Bernstein et al. (1995). For background to hexahydroquinoline compounds and their applications, see: Sausins & Duburs (1988); Nakayama & Kasoaka (1996); Klusa (1995). For the synthesis of related compounds, see: Kumar et al. (2008); Song et al. (2012).

Experimental top

5-Bromsalicylaldehyde (0.201 g, 1 mmol), ethyl acetoacetate (0.25 ml, 1 mmol), dimedone (0.14 g, 1 mmol), ammonium acetate (0.116 g, 1.5 mmol) and ethanol (15 ml) were charged in a round bottom flask. Then the reaction mixture was stirred at room temperature for 12 hours, then the product was separated by filtration. Recrystallization was effected by using ethanol as solvent. Yield 86%. M. p. 520 K.

Refinement top

The O- and N-bound H atoms were located in a difference Fourier map and constrained to ride on their parent atoms with O–H = 0.88 Å, N–H = 0.86 Å and Uiso (H) = 1.5 Ueq(O, N). The C-bound H-atoms were included in calculated positions and treated as riding atoms with C–H = 0.93–0.98 Å and Uiso(H) = 1.2 Ueq(C) or 1.5 Ueq(C) for methyl H atoms. Distance restraints were applied to the components of the disordered ethyl group.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 40% probability displacement ellipsoids.
[Figure 2] Fig. 2. Packing diagram of the title compound viewed down the b axis, showing the linkage of molecules through N—H···O hydrogen interactions (dashed lines). Only H atoms involved in hydrogen bonding are shown.
Ethyl 4-(5-bromo-2-hydroxyphenyl)-2,7,7-trimethyl-5-oxo-1,4,5,6,7,8-hexahydroquinoline-3-carboxylate top
Crystal data top
C21H24BrNO4F(000) = 896
Mr = 434.32Dx = 1.435 Mg m3
Monoclinic, P21/nMelting point: 520 K
Hall symbol: -P 2ynMo Kα radiation, λ = 0.71073 Å
a = 9.5969 (3) ÅCell parameters from 2045 reflections
b = 19.0805 (5) Åθ = 3.3–27.5°
c = 11.0678 (3) ŵ = 2.07 mm1
β = 97.387 (1)°T = 294 K
V = 2009.84 (10) Å3Block, colourless
Z = 40.24 × 0.22 × 0.18 mm
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
5008 independent reflections
Radiation source: fine-focus sealed tube3604 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.022
φ and ω scansθmax = 28.3°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
h = 1212
Tmin = 0.636, Tmax = 0.707k = 2525
23241 measured reflectionsl = 1414
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)] = 0.050Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.136H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0542P)2 + 1.4854P]
where P = (Fo2 + 2Fc2)/3
5008 reflections(Δ/σ)max = 0.001
266 parametersΔρmax = 1.10 e Å3
3 restraintsΔρmin = 1.02 e Å3
Crystal data top
C21H24BrNO4V = 2009.84 (10) Å3
Mr = 434.32Z = 4
Monoclinic, P21/nMo Kα radiation
a = 9.5969 (3) ŵ = 2.07 mm1
b = 19.0805 (5) ÅT = 294 K
c = 11.0678 (3) Å0.24 × 0.22 × 0.18 mm
β = 97.387 (1)°
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
5008 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
3604 reflections with I > 2σ(I)
Tmin = 0.636, Tmax = 0.707Rint = 0.022
23241 measured reflectionsθmax = 28.3°
Refinement top
R[F2 > 2σ(F2)] = 0.050H-atom parameters constrained
wR(F2) = 0.136Δρmax = 1.10 e Å3
S = 1.05Δρmin = 1.02 e Å3
5008 reflectionsAbsolute structure: ?
266 parametersFlack parameter: ?
3 restraintsRogers parameter: ?
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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*/UeqOcc. (<1)
Br10.91668 (4)0.11235 (2)0.50601 (4)0.09330 (19)
O10.4895 (3)0.41833 (11)0.5435 (2)0.0719 (6)
O20.3062 (2)0.18500 (11)0.61555 (16)0.0577 (5)
O30.3634 (2)0.13165 (11)0.79229 (19)0.0597 (5)
O40.4398 (2)0.31539 (12)0.38649 (17)0.0657 (6)
H40.44960.34780.44340.099*
N10.6847 (2)0.28211 (11)0.87199 (18)0.0436 (5)
H10.73480.28200.94220.052*
C10.6826 (2)0.34138 (12)0.8040 (2)0.0392 (5)
C20.7744 (3)0.40011 (14)0.8550 (2)0.0487 (6)
H2A0.86400.38120.89100.058*
H2B0.73120.42280.91930.058*
C30.8001 (3)0.45464 (14)0.7599 (3)0.0507 (6)
C40.6576 (3)0.47395 (14)0.6893 (3)0.0584 (7)
H4A0.60250.49860.74340.070*
H4B0.67260.50570.62380.070*
C50.5754 (3)0.41168 (14)0.6362 (3)0.0494 (6)
C60.5958 (2)0.34543 (12)0.6974 (2)0.0385 (5)
C70.5182 (2)0.28168 (12)0.64397 (19)0.0372 (5)
H7A0.42390.29690.60950.045*
C80.5009 (2)0.22835 (12)0.74306 (19)0.0350 (5)
C90.5861 (2)0.22942 (13)0.85029 (19)0.0379 (5)
C100.5868 (3)0.17973 (17)0.9557 (2)0.0576 (7)
H10A0.59070.13240.92700.086*
H10B0.50280.18620.99300.086*
H10C0.66740.18891.01440.086*
C110.8970 (3)0.42483 (18)0.6729 (3)0.0673 (8)
H11A0.85430.38410.63290.101*
H11B0.98550.41210.71820.101*
H11C0.91200.45960.61320.101*
C120.8689 (4)0.51939 (17)0.8232 (4)0.0734 (9)
H12A0.80850.53830.87790.110*
H12B0.88400.55400.76330.110*
H12C0.95740.50650.86840.110*
C130.3830 (2)0.18055 (13)0.7107 (2)0.0407 (5)
C140.2502 (7)0.0825 (4)0.7444 (6)0.0617 (18)0.633 (10)
H14A0.27040.06120.66900.074*0.633 (10)
H14B0.16060.10660.72950.074*0.633 (10)
C150.2477 (6)0.0278 (4)0.8428 (7)0.080 (2)0.633 (10)
H15A0.17970.00760.81570.120*0.633 (10)
H15B0.22290.04950.91540.120*0.633 (10)
H15C0.33890.00670.85990.120*0.633 (10)
C14'0.2263 (8)0.0963 (5)0.7967 (10)0.051 (3)0.367 (10)
H14C0.15010.12190.75020.061*0.367 (10)
H14D0.20620.09100.87990.061*0.367 (10)
C15'0.2497 (11)0.0255 (6)0.7387 (15)0.094 (5)0.367 (10)
H15D0.16350.00070.72960.141*0.367 (10)
H15E0.32050.00010.78990.141*0.367 (10)
H15F0.27980.03260.66020.141*0.367 (10)
C160.5888 (3)0.25025 (13)0.5398 (2)0.0407 (5)
C170.6996 (3)0.20358 (14)0.5642 (2)0.0459 (6)
H17A0.73310.19220.64440.055*
C180.7603 (3)0.17389 (15)0.4702 (3)0.0561 (7)
C190.7115 (4)0.18797 (18)0.3507 (3)0.0662 (9)
H19A0.75070.16610.28810.079*
C200.6038 (4)0.23495 (18)0.3256 (2)0.0643 (9)
H20A0.57060.24510.24480.077*
C210.5431 (3)0.26783 (15)0.4182 (2)0.0499 (6)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.0748 (3)0.1056 (3)0.1086 (4)0.0222 (2)0.0469 (2)0.0037 (2)
O10.0849 (15)0.0519 (12)0.0703 (14)0.0074 (11)0.0226 (12)0.0177 (10)
O20.0550 (11)0.0705 (13)0.0419 (10)0.0123 (9)0.0152 (8)0.0044 (9)
O30.0498 (11)0.0594 (11)0.0645 (12)0.0181 (9)0.0140 (9)0.0208 (10)
O40.0744 (14)0.0777 (14)0.0404 (10)0.0011 (11)0.0102 (9)0.0150 (10)
N10.0421 (10)0.0523 (12)0.0332 (9)0.0084 (9)0.0066 (8)0.0074 (9)
C10.0378 (11)0.0429 (12)0.0373 (11)0.0015 (9)0.0062 (9)0.0009 (10)
C20.0483 (14)0.0512 (15)0.0459 (14)0.0081 (11)0.0028 (11)0.0035 (11)
C30.0509 (14)0.0430 (14)0.0595 (16)0.0037 (11)0.0123 (12)0.0006 (12)
C40.0626 (17)0.0386 (14)0.0738 (19)0.0055 (12)0.0078 (14)0.0038 (13)
C50.0514 (15)0.0432 (14)0.0526 (15)0.0085 (11)0.0036 (12)0.0053 (11)
C60.0399 (12)0.0405 (12)0.0349 (11)0.0032 (9)0.0040 (9)0.0039 (9)
C70.0373 (11)0.0447 (13)0.0280 (10)0.0021 (9)0.0024 (8)0.0054 (9)
C80.0337 (10)0.0426 (12)0.0284 (10)0.0016 (9)0.0032 (8)0.0042 (9)
C90.0373 (11)0.0463 (13)0.0298 (10)0.0021 (10)0.0031 (8)0.0047 (9)
C100.0631 (17)0.0708 (18)0.0352 (12)0.0208 (14)0.0084 (11)0.0165 (12)
C110.0628 (18)0.070 (2)0.074 (2)0.0017 (15)0.0281 (16)0.0055 (16)
C120.075 (2)0.0544 (18)0.092 (2)0.0175 (16)0.0133 (18)0.0061 (17)
C130.0382 (11)0.0438 (13)0.0388 (12)0.0019 (10)0.0002 (9)0.0021 (10)
C140.061 (3)0.065 (4)0.055 (4)0.022 (3)0.004 (3)0.005 (3)
C150.065 (3)0.084 (4)0.093 (5)0.018 (3)0.012 (3)0.028 (4)
C14'0.047 (4)0.062 (6)0.044 (6)0.012 (4)0.003 (4)0.006 (4)
C15'0.053 (5)0.064 (7)0.169 (16)0.009 (5)0.025 (7)0.002 (8)
C160.0462 (13)0.0448 (13)0.0311 (11)0.0106 (10)0.0046 (9)0.0024 (10)
C170.0461 (13)0.0529 (14)0.0398 (12)0.0080 (11)0.0102 (10)0.0020 (11)
C180.0559 (15)0.0575 (16)0.0594 (17)0.0096 (13)0.0248 (13)0.0029 (13)
C190.081 (2)0.073 (2)0.0509 (16)0.0240 (18)0.0309 (15)0.0138 (15)
C200.081 (2)0.083 (2)0.0298 (12)0.0262 (18)0.0102 (13)0.0010 (13)
C210.0578 (15)0.0581 (16)0.0328 (12)0.0163 (13)0.0022 (10)0.0049 (11)
Geometric parameters (Å, º) top
Br1—C181.907 (3)C10—H10A0.9600
O1—C51.238 (3)C10—H10B0.9600
O2—C131.208 (3)C10—H10C0.9600
O3—C131.329 (3)C11—H11A0.9600
O3—C141.481 (5)C11—H11B0.9600
O3—C14'1.485 (7)C11—H11C0.9600
O4—C211.357 (4)C12—H12A0.9600
O4—H40.8798C12—H12B0.9600
N1—C11.357 (3)C12—H12C0.9600
N1—C91.381 (3)C14—C151.512 (4)
N1—H10.8600C14—H14A0.9700
C1—C61.356 (3)C14—H14B0.9700
C1—C21.491 (3)C15—H15A0.9600
C2—C31.523 (4)C15—H15B0.9600
C2—H2A0.9700C15—H15C0.9600
C2—H2B0.9700C14'—C15'1.526 (5)
C3—C121.528 (4)C14'—H14C0.9700
C3—C41.530 (4)C14'—H14D0.9700
C3—C111.531 (4)C15'—H15D0.9600
C4—C51.503 (4)C15'—H15E0.9600
C4—H4A0.9700C15'—H15F0.9600
C4—H4B0.9700C16—C171.386 (4)
C5—C61.436 (3)C16—C211.402 (3)
C6—C71.507 (3)C17—C181.378 (4)
C7—C81.521 (3)C17—H17A0.9300
C7—C161.532 (3)C18—C191.371 (4)
C7—H7A0.9800C19—C201.369 (5)
C8—C91.352 (3)C19—H19A0.9300
C8—C131.461 (3)C20—C211.392 (4)
C9—C101.503 (3)C20—H20A0.9300
C13—O3—C14111.3 (3)C3—C11—H11A109.5
C13—O3—C14'123.0 (5)C3—C11—H11B109.5
C21—O4—H4106.1H11A—C11—H11B109.5
C1—N1—C9123.33 (19)C3—C11—H11C109.5
C1—N1—H1118.0H11A—C11—H11C109.5
C9—N1—H1116.5H11B—C11—H11C109.5
C6—C1—N1119.6 (2)C3—C12—H12A109.5
C6—C1—C2123.6 (2)C3—C12—H12B109.5
N1—C1—C2116.8 (2)H12A—C12—H12B109.5
C1—C2—C3113.1 (2)C3—C12—H12C109.5
C1—C2—H2A109.0H12A—C12—H12C109.5
C3—C2—H2A109.0H12B—C12—H12C109.5
C1—C2—H2B109.0O2—C13—O3121.2 (2)
C3—C2—H2B109.0O2—C13—C8122.4 (2)
H2A—C2—H2B107.8O3—C13—C8116.37 (19)
C2—C3—C12109.5 (2)O3—C14—C15105.0 (4)
C2—C3—C4107.7 (2)O3—C14—H14A110.8
C12—C3—C4110.2 (2)C15—C14—H14A110.8
C2—C3—C11110.2 (2)O3—C14—H14B110.8
C12—C3—C11109.1 (3)C15—C14—H14B110.8
C4—C3—C11110.1 (3)H14A—C14—H14B108.8
C5—C4—C3113.5 (2)O3—C14'—C15'102.1 (6)
C5—C4—H4A108.9O3—C14'—H14C111.4
C3—C4—H4A108.9C15'—C14'—H14C111.4
C5—C4—H4B108.9O3—C14'—H14D111.4
C3—C4—H4B108.9C15'—C14'—H14D111.4
H4A—C4—H4B107.7H14C—C14'—H14D109.2
O1—C5—C6121.2 (3)C14'—C15'—H15D109.5
O1—C5—C4120.2 (2)C14'—C15'—H15E109.5
C6—C5—C4118.6 (2)H15D—C15'—H15E109.5
C1—C6—C5119.5 (2)C14'—C15'—H15F109.5
C1—C6—C7120.9 (2)H15D—C15'—H15F109.5
C5—C6—C7119.7 (2)H15E—C15'—H15F109.5
C6—C7—C8110.56 (18)C17—C16—C21118.5 (2)
C6—C7—C16111.54 (19)C17—C16—C7120.5 (2)
C8—C7—C16112.36 (19)C21—C16—C7121.0 (2)
C6—C7—H7A107.4C18—C17—C16120.4 (2)
C8—C7—H7A107.4C18—C17—H17A119.8
C16—C7—H7A107.4C16—C17—H17A119.8
C9—C8—C13125.9 (2)C19—C18—C17121.5 (3)
C9—C8—C7120.9 (2)C19—C18—Br1118.9 (2)
C13—C8—C7113.17 (18)C17—C18—Br1119.6 (2)
C8—C9—N1119.2 (2)C20—C19—C18118.7 (3)
C8—C9—C10127.9 (2)C20—C19—H19A120.7
N1—C9—C10112.93 (19)C18—C19—H19A120.7
C9—C10—H10A109.5C19—C20—C21121.5 (3)
C9—C10—H10B109.5C19—C20—H20A119.3
H10A—C10—H10B109.5C21—C20—H20A119.3
C9—C10—H10C109.5O4—C21—C20118.2 (2)
H10A—C10—H10C109.5O4—C21—C16122.4 (2)
H10B—C10—H10C109.5C20—C21—C16119.4 (3)
C9—N1—C1—C611.6 (4)C1—N1—C9—C814.5 (4)
C9—N1—C1—C2166.2 (2)C1—N1—C9—C10164.2 (2)
C6—C1—C2—C319.6 (4)C14—O3—C13—O26.0 (5)
N1—C1—C2—C3162.7 (2)C14'—O3—C13—O221.9 (6)
C1—C2—C3—C12168.6 (2)C14—O3—C13—C8174.5 (4)
C1—C2—C3—C448.8 (3)C14'—O3—C13—C8157.6 (5)
C1—C2—C3—C1171.4 (3)C9—C8—C13—O2175.8 (2)
C2—C3—C4—C553.9 (3)C7—C8—C13—O21.8 (3)
C12—C3—C4—C5173.3 (3)C9—C8—C13—O33.7 (4)
C11—C3—C4—C566.4 (3)C7—C8—C13—O3178.8 (2)
C3—C4—C5—O1152.6 (3)C13—O3—C14—C15176.1 (5)
C3—C4—C5—C629.2 (4)C14'—O3—C14—C1562.6 (10)
N1—C1—C6—C5169.3 (2)C13—O3—C14'—C15'102.7 (10)
C2—C1—C6—C58.3 (4)C14—O3—C14'—C15'31.1 (9)
N1—C1—C6—C79.4 (3)C6—C7—C16—C1784.8 (3)
C2—C1—C6—C7173.0 (2)C8—C7—C16—C1740.0 (3)
O1—C5—C6—C1174.8 (3)C6—C7—C16—C2195.2 (3)
C4—C5—C6—C13.3 (4)C8—C7—C16—C21140.0 (2)
O1—C5—C6—C73.9 (4)C21—C16—C17—C181.8 (4)
C4—C5—C6—C7178.0 (2)C7—C16—C17—C18178.2 (2)
C1—C6—C7—C824.1 (3)C16—C17—C18—C191.6 (4)
C5—C6—C7—C8154.6 (2)C16—C17—C18—Br1177.85 (19)
C1—C6—C7—C16101.7 (2)C17—C18—C19—C202.8 (4)
C5—C6—C7—C1679.6 (3)Br1—C18—C19—C20176.7 (2)
C6—C7—C8—C921.1 (3)C18—C19—C20—C210.5 (5)
C16—C7—C8—C9104.2 (2)C19—C20—C21—O4178.0 (3)
C6—C7—C8—C13156.56 (19)C19—C20—C21—C162.8 (4)
C16—C7—C8—C1378.1 (2)C17—C16—C21—O4177.0 (2)
C13—C8—C9—N1173.8 (2)C7—C16—C21—O43.1 (4)
C7—C8—C9—N13.6 (3)C17—C16—C21—C203.9 (4)
C13—C8—C9—C104.8 (4)C7—C16—C21—C20176.0 (2)
C7—C8—C9—C10177.8 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O4—H4···O10.881.752.625 (3)171
N1—H1···O2i0.862.052.866 (3)158
Symmetry code: (i) x+1/2, y+1/2, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O4—H4···O10.881.752.625 (3)171
N1—H1···O2i0.862.052.866 (3)158
Symmetry code: (i) x+1/2, y+1/2, z+1/2.
Acknowledgements top

The authors thank the Chemistry Department [at which University?] for providing the X-ray diffraction facility.

references
References top

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