6,6,7,7-Tetra­chloro-5,6,7,8-tetra­hydro­quinoline-5,8-dione

The oxidation reaction between 8-hydroxy­quinoline and hydro­chloric acid yields 6,6,7,7-tetra­chloro-5,6,7,8-tetra­hydro­quinoline-5,8-dione, C₉H₃Cl₄NO. The non-aromatic part of the fused ring is non-planar; one of the chlorine-substituted C atoms lies above the mean plane of the fused ring, whereas the other lies below it.

Key indicators

• Single-crystal X-ray study
• T = 295 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.047
• wR factor = 0.139
• Data-to-parameter ratio = 16.8

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT230_ALERT_2_B Hirshfeld Test Diff for    Cl1    -   C7      ..       8.07 su
PLAT230_ALERT_2_B Hirshfeld Test Diff for    Cl4    -   C6      ..       8.04 su

Alert level C
ABSTM02_ALERT_3_C  The ratio of Tmax/Tmin expected RT(exp) is > 1.10
            Absorption corrections should be applied.
            Tmin and Tmax expected:      0.615     0.686
            RT(exp) =      1.117
PLAT057_ALERT_3_C Correction for Absorption Required   RT(exp) ...       1.12
PLAT340_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          5
PLAT431_ALERT_2_C Short Inter HL..A Contact  Cl1    ..  O1      ..       3.20 Ang.

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           27.05
           From the CIF: _reflns_number_total               2436
           Count of symmetry unique reflns         1429
           Completeness (_total/calc)            170.47%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured      1007
           Fraction of Friedel pairs measured     0.705
           Are heavy atom types Z>Si present        yes

   0 ALERT level A = In general: serious problem
   2 ALERT level B = Potentially serious problem
   4 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 ALERT type 2 Indicator that the structure model may be wrong or deficient
   3 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2007).

6,6,7,7-Tetrachloro-5,6,7,8-tetrahydroquinoline-5,8-dione

Crystal data

C9H3Cl4NO2	F(000) = 592
Mr = 298.92	Dx = 1.787 Mg m^−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 4235 reflections
a = 7.6115 (4) Å	θ = 2.4–27.1°
b = 10.3015 (6) Å	µ = 1.05 mm^−1
c = 14.1723 (8) Å	T = 295 K
V = 1111.3 (1) Å^3	Irregular block, yellow
Z = 4	0.48 × 0.46 × 0.36 mm

Data collection

Bruker SMART area-detector diffractometer	2195 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.028
Graphite monochromator	θmax = 27.1°, θmin = 2.4°
φ and ω scans	h = −8→9
6576 measured reflections	k = −11→13
2436 independent reflections	l = −16→18

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.047	H-atom parameters constrained
wR(F^2) = 0.139	w = 1/[σ^2(Fo^2) + (0.0832P)^2 + 0.5204P] where P = (Fo^2 + 2Fc^2)/3
S = 1.07	(Δ/σ)max = 0.001
2436 reflections	Δρmax = 0.62 e Å^−3
145 parameters	Δρmin = −0.36 e Å^−3
0 restraints	Absolute structure: Flack (1983), 1012 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.1 (1)

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Cl1	0.6837 (2)	1.0738 (1)	0.2945 (1)	0.0731 (4)
Cl2	0.5294 (2)	0.8383 (2)	0.37392 (8)	0.0771 (4)
Cl3	0.8557 (2)	0.9658 (1)	0.48699 (7)	0.0650 (3)
Cl4	0.9238 (2)	0.7209 (1)	0.38760 (7)	0.0788 (4)
O1	0.6123 (3)	0.7922 (4)	0.1804 (2)	0.0632 (9)
O2	1.1445 (4)	1.0148 (4)	0.3620 (2)	0.0737 (10)
N1	0.9195 (4)	0.8203 (3)	0.0822 (2)	0.0445 (7)
C1	1.0745 (6)	0.8354 (4)	0.0395 (3)	0.0494 (9)
H1	1.0838	0.8092	−0.0232	0.059*
C2	1.2200 (5)	0.8864 (4)	0.0814 (3)	0.0518 (9)
H2	1.3244	0.8948	0.0479	0.062*
C3	1.2102 (5)	0.9254 (4)	0.1741 (3)	0.0505 (9)
H3	1.3069	0.9619	0.2042	0.061*
C4	1.0522 (5)	0.9088 (3)	0.2218 (2)	0.0374 (7)
C5	1.0388 (5)	0.9500 (4)	0.3227 (3)	0.0474 (8)
C6	0.8792 (6)	0.8921 (4)	0.3759 (3)	0.0516 (9)
C7	0.7150 (5)	0.9025 (4)	0.3170 (3)	0.0489 (9)
C8	0.7356 (5)	0.8397 (4)	0.2182 (2)	0.0420 (8)
C9	0.9104 (4)	0.8563 (3)	0.1731 (2)	0.0337 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.0840 (8)	0.0591 (6)	0.0762 (7)	0.0339 (6)	0.0152 (6)	0.0031 (5)
Cl2	0.0641 (7)	0.1226 (11)	0.0446 (6)	−0.0355 (7)	0.0198 (5)	−0.0101 (6)
Cl3	0.0719 (7)	0.0856 (7)	0.0376 (5)	−0.0054 (6)	0.0051 (5)	−0.0271 (5)
Cl4	0.144 (1)	0.0507 (5)	0.0421 (5)	0.0215 (7)	−0.0030 (7)	0.0096 (4)
O1	0.043 (2)	0.103 (2)	0.043 (2)	−0.019 (2)	−0.001 (1)	−0.017 (2)
O2	0.055 (2)	0.098 (2)	0.069 (2)	−0.020 (2)	−0.002 (2)	−0.047 (2)
N1	0.049 (2)	0.059 (2)	0.026 (1)	0.002 (1)	0.000 (1)	0.000 (1)
C1	0.058 (2)	0.061 (2)	0.029 (2)	0.010 (2)	0.009 (2)	0.002 (2)
C2	0.044 (2)	0.064 (2)	0.048 (2)	0.000 (2)	0.013 (2)	0.000 (2)
C3	0.034 (2)	0.061 (2)	0.057 (2)	−0.005 (2)	0.006 (2)	−0.006 (2)
C4	0.037 (2)	0.037 (2)	0.038 (2)	0.006 (1)	0.003 (1)	−0.003 (1)
C5	0.040 (2)	0.057 (2)	0.045 (2)	0.000 (2)	−0.003 (2)	−0.015 (2)
C6	0.062 (2)	0.058 (2)	0.035 (2)	−0.003 (2)	0.001 (2)	−0.011 (2)
C7	0.043 (2)	0.066 (2)	0.038 (2)	−0.004 (2)	0.010 (2)	−0.005 (2)
C8	0.045 (2)	0.052 (2)	0.029 (2)	−0.008 (2)	0.000 (1)	−0.003 (2)
C9	0.038 (2)	0.034 (1)	0.029 (1)	0.002 (1)	−0.003 (1)	0.001 (1)

Geometric parameters (Å, º)

Cl1—C7	1.809 (4)	C3—C4	1.390 (5)
Cl2—C7	1.756 (4)	C4—C9	1.391 (5)
Cl3—C6	1.757 (4)	C4—C5	1.494 (5)
Cl4—C6	1.804 (4)	C5—C6	1.550 (6)
O1—C8	1.186 (4)	C6—C7	1.506 (6)
O2—C5	1.185 (5)	C7—C8	1.551 (5)
N1—C1	1.335 (5)	C8—C9	1.487 (5)
N1—C9	1.343 (4)	C1—H1	0.93
C1—C2	1.363 (6)	C2—H2	0.93
C2—C3	1.376 (6)	C3—H3	0.93
C1—N1—C9	116.6 (3)	C6—C7—Cl2	112.7 (3)
N1—C1—C2	124.4 (3)	C8—C7—Cl2	109.8 (3)
C1—C2—C3	119.0 (4)	C6—C7—Cl1	106.1 (3)
C2—C3—C4	118.4 (4)	C8—C7—Cl1	105.1 (3)
C3—C4—C9	118.5 (3)	Cl2—C7—Cl1	110.0 (2)
C3—C4—C5	119.3 (3)	O1—C8—C9	124.1 (3)
C9—C4—C5	122.2 (3)	O1—C8—C7	120.1 (3)
O2—C5—C4	124.3 (4)	C9—C8—C7	115.5 (3)
O2—C5—C6	121.4 (4)	N1—C9—C4	123.0 (3)
C4—C5—C6	114.2 (3)	N1—C9—C8	115.3 (3)
C7—C6—C5	110.7 (3)	C4—C9—C8	121.7 (3)
C7—C6—Cl3	112.4 (3)	N1—C1—H1	117.8
C5—C6—Cl3	110.5 (3)	C2—C1—H1	117.8
C7—C6—Cl4	106.1 (3)	C1—C2—H2	120.5
C5—C6—Cl4	105.9 (3)	C3—C2—H2	120.5
Cl3—C6—Cl4	111.0 (2)	C2—C3—H3	120.8
C6—C7—C8	112.7 (3)	C4—C3—H3	120.8
C9—N1—C1—C2	−1.3 (6)	Cl4—C6—C7—Cl2	65.6 (3)
N1—C1—C2—C3	0.3 (7)	C5—C6—C7—Cl1	−59.5 (3)
C1—C2—C3—C4	1.1 (6)	Cl3—C6—C7—Cl1	64.5 (3)
C2—C3—C4—C9	−1.4 (6)	Cl4—C6—C7—Cl1	−173.9 (2)
C2—C3—C4—C5	179.8 (4)	C6—C7—C8—O1	148.9 (4)
C3—C4—C5—O2	12.4 (6)	Cl2—C7—C8—O1	22.4 (5)
C9—C4—C5—O2	−166.3 (4)	Cl1—C7—C8—O1	−96.0 (4)
C3—C4—C5—C6	−163.3 (3)	C6—C7—C8—C9	−37.2 (5)
C9—C4—C5—C6	18.0 (5)	Cl2—C7—C8—C9	−163.8 (3)
O2—C5—C6—C7	138.6 (4)	Cl1—C7—C8—C9	77.8 (3)
C4—C5—C6—C7	−45.5 (4)	C1—N1—C9—C4	0.9 (5)
O2—C5—C6—Cl3	13.4 (5)	C1—N1—C9—C8	179.4 (3)
C4—C5—C6—Cl3	−170.7 (3)	C3—C4—C9—N1	0.4 (5)
O2—C5—C6—Cl4	−106.9 (4)	C5—C4—C9—N1	179.2 (3)
C4—C5—C6—Cl4	69.0 (4)	C3—C4—C9—C8	−177.9 (3)
C5—C6—C7—C8	55.0 (4)	C5—C4—C9—C8	0.8 (5)
Cl3—C6—C7—C8	179.1 (3)	O1—C8—C9—N1	3.7 (6)
Cl4—C6—C7—C8	−59.4 (4)	C7—C8—C9—N1	−169.9 (3)
C5—C6—C7—Cl2	180.0 (3)	O1—C8—C9—C4	−177.9 (4)
Cl3—C6—C7—Cl2	−55.9 (4)	C7—C8—C9—C4	8.6 (5)