N,N′-Di-8-quinolyl-2,2′-(o-phenyl­ene­di­oxy)diacetamide

In the title compound, C₂₈H₂₂N₄O₄, the mol­ecule lies on a crystallographic twofold axis. The quinoline ring is essentially planar (give max or rms deviation 0.0186 Å), and the dihedral angle between the quinoline ring and the central benzene ring is 19.1 (4)°. Intra­molecular N—H...(N,O) and C—H...O hydrogen bonds contribute to the formation of the roughly planar configuration. The crystal packing is stabilized by inter­molecular C—H...O hydrogen bonds, and weak π–π inter­actions between the pyridine rings and central benzene rings of the neighboring mol­ecules [centroid–centroid separation = 3.9009 (6) Å].

Key indicators

• Single-crystal X-ray study
• T = 294 K
• Mean [sigma](C-C) = 0.006 Å
• R factor = 0.037
• wR factor = 0.083
• Data-to-parameter ratio = 6.5

checkCIF/PLATON results

No syntax errors found



Alert level A
REFI021_ALERT_1_A  _refine_ls_abs_structure_details is missing
            Absolute structure method and Friedel-pair number.
            This should be present as the _refine_ls_abs_structure_Flack or Roge
            field has been filled out.
PLAT923_ALERT_1_A S    values in the CIF and FCF Differ by .......      -0.13

Alert level B
PLAT915_ALERT_3_B Low Friedel Pair Coverage ......................      49.18 Perc.
PLAT921_ALERT_1_B R1  * 100.0 in the CIF and FCF Differ by .......      -0.77
PLAT922_ALERT_1_B wR2 * 100.0 in the CIF and FCF Differ by .......      -2.24
PLAT926_ALERT_1_B Reported and Calculated   R1 * 100.0 Differ by .      -0.69
PLAT927_ALERT_1_B Reported and Calculated  wR2 * 100.0 Differ by .      -2.41

Alert level C
STRVA01_ALERT_4_C           Flack test results are meaningless.
           From the CIF: _refine_ls_abs_structure_Flack    0.000
           From the CIF: _refine_ls_abs_structure_Flack_su    2.000
PLAT089_ALERT_3_C Poor Data / Parameter Ratio (Zmax .LT. 18) .....       6.47
PLAT340_ALERT_3_C Low Bond Precision on  C-C Bonds (x 1000) Ang ..          6
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.595          3
PLAT032_ALERT_4_C Std. Uncertainty in Flack Parameter too High ...       2.00
PLAT158_ALERT_4_C The Input Unitcell is NOT Standard/Reduced .....          ?
PLAT234_ALERT_4_C Large Hirshfeld Difference C5     --  C6      ..       0.15 Ang.
PLAT928_ALERT_1_C Reported and Calculated    S value   Differ by .      -0.14

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           25.02
           From the CIF: _reflns_number_total               1080
           Count of symmetry unique reflns         1083
           Completeness (_total/calc)             99.72%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present         no
PLAT850_ALERT_4_G Check Flack Parameter Exact Value 0.00 and su ..       2.00

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

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

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S1. Comment

The amide-type acyclic polyethers have attracted wide attention in coordination chemistry and separation science because they have good complexing ability (West et al., 1992) and high selectivity to metal ions (Wen et al., 2002). In addition, this kind of compounds have been used successfully as active materials for ion-selective electrodes (Guggi et al., 1977). Here, we report the synthesis and structure of the title compound.

The asymmetric unit of (I) contains one half-molecule, the other half being related by a crystallographic twofold axis (Fig. 1). All bond lengths and angles in (I) are within normal ranges, and comparable with those in the related compound (Wen et al., 2005). The quinoline ring is essentially planar, with a dihedral angle of 2.1 (2)° between the benzene (C4—C9) ring and pyridine (C1—C4/C9/N1) ring. The dihedral angle between the quinoline ring and the central benzene ring is 19.1 (4)°. The amide N and C atoms are also planar configuration because the sum of the angles around atoms N2 and C10 are 359.3° and 360.0°, respectively. The intramolecular hydrogen bonds, N2—H2A···N1, N2—H2A···O2 and C7-H7···O1, form stable five- and six-membered rings, this being helpful to the formation of the planar configuration. The crystal packing is stabilized by intermolecular C11—H11B···O1 hydrogen bonds, and π-π interactions [short centroid-centroid separation = 3.9009 (6) Å] between the pyridine rings and central benzene rings of the neighboring molecules (Table 1 and Fig. 2).

Related literature

For background to the applications of amide-type acyclic polyethers, see: Guggi et al. (1977); Wen et al. (2002); West et al. (1992). For a related amide-type acyclic polyether structure, see: Wen et al. (2005).

S2. Experimental

Compound (I) was prepared according to the literature method of Wen et al. (2005). Yellow single crystals suitable for an X-ray diffraction study were obtained by slow evaporation of a petroleum ether-ethyl acetate solution (1:3 v/v) over a period of 10 d.

S3. Refinement

H atoms were positioned geometrically, with N—H = 0.86 Å and C—H = 0.95–0.99 Å, respectively, and constrained to ride on their parent atoms, with U_iso(H) = 1.2 U_eq(C,N). Absolute structure cannot be determined reliably.

Computing details

Data collection: SMART (Bruker 2001); cell refinement: SMART (Bruker 2001); data reduction: SAINT (Bruker 2001); program(s) used to solve structure: SHELXTL (Sheldrick, 2001); program(s) used to refine structure: SHELXTL (Sheldrick, 2001); molecular graphics: SHELXTL (Sheldrick, 2001); software used to prepare material for publication: SHELXTL (Sheldrick, 2001).

Figures

	Fig. 1. The molecular structure of (I), with atom labels and 20% probability displacement ellipsoids. [Symmetry code: (i) -x, 2-y, z].
	Fig. 2. The packing diagram of (I) viewed down c-axis. Intermolecular H-bonds are indicated by dashed lines. H atoms were omitted for clearance.

N,N'-Di-8-quinolyl-2,2'-(o-phenylenedioxy)diacetamide

Crystal data

C28H22N4O4	F(000) = 2000
Mr = 478.50	Dx = 1.358 Mg m^−3
Orthorhombic, Fdd2	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: F 2 -2d	Cell parameters from 925 reflections
a = 32.648 (14) Å	θ = 2.5–20.7°
b = 11.459 (4) Å	µ = 0.09 mm^−1
c = 12.516 (5) Å	T = 294 K
V = 4682 (3) Å^3	Prism, yellow
Z = 8	0.20 × 0.14 × 0.12 mm

Data collection

Bruker SMART CCD area-detector diffractometer	1080 independent reflections
Radiation source: fine-focus sealed tube	670 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.060
phi and ω scans	θmax = 25.0°, θmin = 2.5°
Absorption correction: multi-scan (SADABS; Sheldrick,1996)	h = −38→34
Tmin = 0.982, Tmax = 0.989	k = −12→13
4687 measured reflections	l = −14→11

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.037	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.083	H atoms treated by a mixture of independent and constrained refinement
S = 1.00	w = 1/[σ^2(Fo^2) + (0.0372P)^2] where P = (Fo^2 + 2Fc^2)/3
1080 reflections	(Δ/σ)max < 0.001
167 parameters	Δρmax = 0.15 e Å^−3
1 restraint	Δρmin = −0.16 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
O1	0.13016 (8)	1.0567 (3)	0.5394 (3)	0.0891 (10)
O2	0.03851 (7)	1.0165 (2)	0.39873 (19)	0.0631 (8)
N1	0.00878 (10)	0.8564 (3)	0.6781 (2)	0.0567 (8)
N2	0.07030 (10)	0.9673 (3)	0.5830 (3)	0.0588 (9)
C1	−0.02253 (12)	0.8058 (3)	0.7257 (3)	0.0617 (11)
H1	−0.0457	0.7900	0.6851	0.074*
C2	−0.02300 (13)	0.7745 (4)	0.8338 (4)	0.0695 (12)
H2	−0.0460	0.7392	0.8634	0.083*
C3	0.01028 (14)	0.7961 (4)	0.8944 (4)	0.0712 (12)
H3	0.0104	0.7760	0.9664	0.085*
C4	0.04461 (13)	0.8488 (3)	0.8485 (3)	0.0588 (10)
C5	0.08058 (15)	0.8758 (4)	0.9066 (4)	0.0772 (12)
H5	0.0827	0.8552	0.9783	0.093*
C6	0.11176 (16)	0.9313 (4)	0.8577 (4)	0.0818 (15)
H6	0.1352	0.9484	0.8968	0.098*
C7	0.11003 (13)	0.9644 (4)	0.7497 (4)	0.0717 (12)
H7	0.1319	1.0034	0.7182	0.086*
C8	0.07540 (11)	0.9384 (3)	0.6908 (3)	0.0562 (10)
C9	0.04230 (11)	0.8797 (3)	0.7402 (3)	0.0513 (10)
C10	0.09592 (12)	1.0223 (3)	0.5173 (3)	0.0599 (11)
C11	0.08113 (11)	1.0392 (3)	0.4046 (4)	0.0635 (11)
H11A	0.0866	1.1186	0.3818	0.076*
H11B	0.0957	0.9867	0.3571	0.076*
C12	0.02089 (10)	1.0103 (3)	0.2991 (3)	0.0583 (10)
C13	0.04141 (13)	1.0219 (3)	0.2046 (3)	0.0728 (12)
H13	0.0694	1.0369	0.2043	0.087*
C14	0.02013 (13)	1.0111 (4)	0.1088 (4)	0.0905 (17)
H14	0.0340	1.0194	0.0443	0.109*
H2A	0.0455 (12)	0.947 (3)	0.560 (3)	0.077 (14)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0467 (16)	0.098 (2)	0.122 (2)	−0.0231 (15)	−0.007 (2)	0.003 (2)
O2	0.0432 (15)	0.086 (2)	0.0598 (18)	−0.0090 (13)	0.0050 (14)	−0.0031 (14)
N1	0.0398 (18)	0.055 (2)	0.075 (2)	0.0006 (16)	−0.0048 (18)	−0.0033 (16)
N2	0.036 (2)	0.065 (2)	0.075 (3)	−0.0069 (18)	−0.0018 (19)	−0.0029 (17)
C1	0.046 (3)	0.055 (2)	0.084 (3)	0.002 (2)	−0.004 (2)	−0.001 (2)
C2	0.068 (3)	0.061 (3)	0.080 (3)	0.002 (2)	0.012 (2)	−0.003 (2)
C3	0.087 (3)	0.062 (3)	0.064 (3)	0.011 (3)	0.002 (3)	−0.005 (2)
C4	0.060 (3)	0.049 (2)	0.067 (3)	0.009 (2)	−0.010 (2)	−0.0103 (19)
C5	0.090 (3)	0.068 (3)	0.073 (3)	0.010 (3)	−0.020 (3)	−0.006 (2)
C6	0.076 (4)	0.068 (3)	0.102 (4)	0.014 (3)	−0.045 (3)	−0.017 (3)
C7	0.053 (3)	0.066 (3)	0.097 (3)	0.000 (2)	−0.018 (2)	−0.008 (2)
C8	0.044 (3)	0.056 (2)	0.069 (3)	0.004 (2)	−0.010 (2)	−0.0128 (19)
C9	0.045 (2)	0.040 (2)	0.069 (3)	0.0099 (18)	−0.004 (2)	−0.0094 (19)
C10	0.040 (2)	0.053 (3)	0.087 (3)	0.001 (2)	0.005 (2)	−0.007 (2)
C11	0.043 (2)	0.060 (2)	0.088 (3)	−0.0094 (18)	0.011 (2)	0.000 (2)
C12	0.067 (2)	0.052 (2)	0.055 (2)	0.005 (2)	0.005 (2)	0.0020 (18)
C13	0.079 (3)	0.067 (3)	0.072 (3)	0.003 (2)	0.014 (3)	0.009 (2)
C14	0.124 (4)	0.087 (4)	0.061 (3)	0.024 (4)	0.013 (3)	0.005 (3)

Geometric parameters (Å, º)

O1—C10	1.217 (4)	C5—C6	1.348 (6)
O2—C12	1.375 (4)	C5—H5	0.9300
O2—C11	1.417 (4)	C6—C7	1.406 (6)
N1—C1	1.317 (4)	C6—H6	0.9300
N1—C9	1.369 (4)	C7—C8	1.382 (5)
N2—C10	1.332 (5)	C7—H7	0.9300
N2—C8	1.399 (5)	C8—C9	1.415 (5)
N2—H2A	0.89 (4)	C10—C11	1.504 (5)
C1—C2	1.400 (5)	C11—H11A	0.9700
C1—H1	0.9300	C11—H11B	0.9700
C2—C3	1.348 (5)	C12—C13	1.366 (5)
C2—H2	0.9300	C12—C12^i	1.384 (7)
C3—C4	1.397 (5)	C13—C14	1.391 (6)
C3—H3	0.9300	C13—H13	0.9300
C4—C9	1.403 (4)	C14—C14^i	1.339 (9)
C4—C5	1.416 (5)	C14—H14	0.9300
C12—O2—C11	117.8 (3)	C6—C7—H7	120.4
C1—N1—C9	116.7 (3)	C7—C8—N2	124.1 (4)
C10—N2—C8	129.3 (4)	C7—C8—C9	119.6 (4)
C10—N2—H2A	120 (3)	N2—C8—C9	116.3 (3)
C8—N2—H2A	111 (3)	N1—C9—C4	122.9 (3)
N1—C1—C2	124.0 (4)	N1—C9—C8	117.1 (3)
N1—C1—H1	118.0	C4—C9—C8	120.1 (4)
C2—C1—H1	118.0	O1—C10—N2	126.1 (4)
C3—C2—C1	119.2 (4)	O1—C10—C11	117.8 (4)
C3—C2—H2	120.4	N2—C10—C11	116.0 (3)
C1—C2—H2	120.4	O2—C11—C10	109.9 (3)
C2—C3—C4	119.7 (4)	O2—C11—H11A	109.7
C2—C3—H3	120.2	C10—C11—H11A	109.7
C4—C3—H3	120.2	O2—C11—H11B	109.7
C3—C4—C9	117.6 (4)	C10—C11—H11B	109.7
C3—C4—C5	123.3 (4)	H11A—C11—H11B	108.2
C9—C4—C5	119.1 (4)	C13—C12—O2	125.1 (3)
C6—C5—C4	119.7 (4)	C13—C12—C12^i	120.0 (2)
C6—C5—H5	120.1	O2—C12—C12^i	114.91 (16)
C4—C5—H5	120.1	C12—C13—C14	119.5 (4)
C5—C6—C7	122.3 (4)	C12—C13—H13	120.2
C5—C6—H6	118.8	C14—C13—H13	120.2
C7—C6—H6	118.8	C14^i—C14—C13	120.5 (2)
C8—C7—C6	119.2 (5)	C14^i—C14—H14	119.8
C8—C7—H7	120.4	C13—C14—H14	119.8
C9—N1—C1—C2	−0.6 (6)	C3—C4—C9—C8	176.9 (4)
N1—C1—C2—C3	−0.2 (7)	C5—C4—C9—C8	−0.8 (5)
C1—C2—C3—C4	−0.3 (6)	C7—C8—C9—N1	179.8 (3)
C2—C3—C4—C9	1.5 (6)	N2—C8—C9—N1	0.4 (4)
C2—C3—C4—C5	179.2 (4)	C7—C8—C9—C4	0.3 (5)
C3—C4—C5—C6	−177.1 (4)	N2—C8—C9—C4	−179.1 (3)
C9—C4—C5—C6	0.6 (6)	C8—N2—C10—O1	1.7 (6)
C4—C5—C6—C7	0.1 (7)	C8—N2—C10—C11	179.5 (3)
C5—C6—C7—C8	−0.6 (7)	C12—O2—C11—C10	−170.3 (3)
C6—C7—C8—N2	179.8 (4)	O1—C10—C11—O2	−168.2 (3)
C6—C7—C8—C9	0.4 (6)	N2—C10—C11—O2	13.8 (4)
C10—N2—C8—C7	0.3 (6)	C11—O2—C12—C13	1.5 (5)
C10—N2—C8—C9	179.7 (3)	C11—O2—C12—C12^i	−179.1 (4)
C1—N1—C9—C4	2.0 (5)	O2—C12—C13—C14	178.5 (3)
C1—N1—C9—C8	−177.4 (3)	C12^i—C12—C13—C14	−0.9 (7)
C3—C4—C9—N1	−2.5 (5)	C12—C13—C14—C14^i	−0.4 (8)
C5—C4—C9—N1	179.7 (3)

Symmetry code: (i) −x, −y+2, z.