In the title compound, C
18H
18N
2O
4, the molecule has a crystallographically imposed center of symmetry. The dihedral angles between the piperazinedione ring and the two outer aromatic rings are 57.25 (7)°. Molecules of (I) interact
via weak intermolecular C—H
O interactions, forming ribbons along the
b axis.
Supporting information
CCDC reference: 251645
Key indicators
- Single-crystal X-ray study
- T = 293 K
- Mean (C-C) = 0.002 Å
- R factor = 0.042
- wR factor = 0.119
- Data-to-parameter ratio = 10.7
checkCIF/PLATON results
No syntax errors found
Alert level C
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical . ?
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given ....... ?
0 ALERT level A = In general: serious problem
0 ALERT level B = Potentially serious problem
2 ALERT level C = Check and explain
0 ALERT level G = General alerts; check
1 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
0 ALERT type 3 Indicator that the structure quality may be low
1 ALERT type 4 Improvement, methodology, query or suggestion
Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 1997); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL, PARST (Nardelli, 1995) and PLATON (Spek, 1990).
1,4-Bis(4-methoxyphenyl)piperazine-2,5-dione
top
Crystal data top
C18H18N2O4 | F(000) = 344 |
Mr = 326.24 | Dx = 1.368 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 16.9231 (17) Å | Cell parameters from 4504 reflections |
b = 5.8166 (6) Å | θ = 2.4–26.1° |
c = 8.0580 (8) Å | µ = 0.10 mm−1 |
β = 92.687 (2)° | T = 293 K |
V = 792.32 (14) Å3 | Column, colorless |
Z = 2 | 0.42 × 0.21 × 0.19 mm |
Data collection top
Simens SMART 1000 CCD area-detector diffractometer | 1557 independent reflections |
Radiation source: fine-focus sealed tube | 1318 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.018 |
Detector resolution: 8.33 pixels mm-1 | θmax = 26.1°, θmin = 2.4° |
ω scans | h = −18→20 |
Absorption correction: empirical (using intensity measurements) (SADABS; Sheldrick, 1996) | k = −7→6 |
Tmin = 0.960, Tmax = 0.982 | l = −8→9 |
4225 measured reflections | |
Refinement top
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.042 | All H-atom parameters refined |
wR(F2) = 0.119 | w = 1/[σ2(Fo2) + (0.0631P)2 + 0.1534P] where P = (Fo2 + 2Fc2)/3 |
S = 1.04 | (Δ/σ)max < 0.001 |
1557 reflections | Δρmax = 0.15 e Å−3 |
146 parameters | Δρmin = −0.15 e Å−3 |
0 restraints | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.028 (5) |
Special details top
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. |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Uiso*/Ueq | |
O1 | 0.91274 (6) | 0.0420 (2) | 0.59156 (18) | 0.0707 (4) | |
O2 | 0.57510 (6) | −0.32730 (17) | 0.67867 (14) | 0.0527 (3) | |
N1 | 0.58278 (6) | 0.00831 (18) | 0.53827 (14) | 0.0372 (3) | |
C1 | 0.95255 (12) | 0.2387 (4) | 0.6576 (4) | 0.0768 (6) | |
H1C | 1.0084 (14) | 0.206 (4) | 0.650 (3) | 0.093 (7)* | |
H1B | 0.9340 (12) | 0.385 (4) | 0.591 (3) | 0.091 (7)* | |
H1A | 0.9410 (14) | 0.268 (4) | 0.772 (4) | 0.115 (9)* | |
C2 | 0.83149 (8) | 0.0451 (3) | 0.5847 (2) | 0.0491 (4) | |
C3 | 0.79465 (9) | −0.1439 (3) | 0.5095 (2) | 0.0543 (4) | |
H3 | 0.8273 (10) | −0.268 (3) | 0.466 (2) | 0.067 (5)* | |
C4 | 0.71347 (9) | −0.1567 (3) | 0.4950 (2) | 0.0481 (4) | |
H4 | 0.6873 (9) | −0.286 (3) | 0.439 (2) | 0.054 (4)* | |
C5 | 0.66774 (8) | 0.0189 (2) | 0.55692 (16) | 0.0387 (4) | |
C6 | 0.70421 (9) | 0.2080 (3) | 0.62934 (19) | 0.0460 (4) | |
H6 | 0.6719 (10) | 0.332 (3) | 0.668 (2) | 0.062 (5)* | |
C7 | 0.78627 (9) | 0.2220 (3) | 0.6440 (2) | 0.0509 (4) | |
H7 | 0.8099 (10) | 0.355 (3) | 0.693 (2) | 0.068 (5)* | |
C8 | 0.54371 (8) | 0.1941 (2) | 0.44506 (19) | 0.0397 (4) | |
H8B | 0.5690 (10) | 0.213 (3) | 0.340 (2) | 0.057 (5)* | |
C9 | 0.54327 (8) | −0.1734 (2) | 0.59541 (16) | 0.0372 (3) | |
H8A | 0.5512 (9) | 0.338 (3) | 0.506 (2) | 0.058 (5)* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
O1 | 0.0371 (6) | 0.0754 (9) | 0.0992 (10) | 0.0025 (6) | −0.0018 (6) | −0.0069 (7) |
O2 | 0.0495 (6) | 0.0455 (6) | 0.0619 (7) | 0.0015 (4) | −0.0088 (5) | 0.0178 (5) |
N1 | 0.0361 (6) | 0.0341 (6) | 0.0411 (6) | 0.0019 (4) | −0.0005 (5) | 0.0023 (4) |
C1 | 0.0435 (10) | 0.0915 (16) | 0.0948 (17) | −0.0083 (10) | −0.0042 (10) | −0.0103 (13) |
C2 | 0.0377 (8) | 0.0561 (9) | 0.0534 (9) | 0.0031 (6) | 0.0005 (6) | 0.0048 (7) |
C3 | 0.0455 (8) | 0.0479 (9) | 0.0696 (11) | 0.0098 (7) | 0.0033 (7) | −0.0036 (8) |
C4 | 0.0455 (8) | 0.0406 (8) | 0.0579 (9) | 0.0039 (6) | −0.0016 (7) | −0.0054 (7) |
C5 | 0.0378 (7) | 0.0398 (7) | 0.0382 (7) | 0.0015 (5) | 0.0001 (5) | 0.0036 (5) |
C6 | 0.0422 (8) | 0.0451 (8) | 0.0511 (9) | 0.0009 (6) | 0.0053 (6) | −0.0071 (6) |
C7 | 0.0456 (9) | 0.0528 (9) | 0.0543 (9) | −0.0062 (7) | 0.0013 (7) | −0.0085 (7) |
C8 | 0.0423 (8) | 0.0312 (7) | 0.0453 (8) | 0.0018 (5) | −0.0005 (6) | 0.0043 (6) |
C9 | 0.0430 (7) | 0.0332 (7) | 0.0352 (7) | 0.0022 (5) | −0.0002 (5) | 0.0001 (5) |
Geometric parameters (Å, º) top
O1—C2 | 1.3736 (18) | C3—H3 | 0.984 (18) |
O1—C1 | 1.419 (2) | C4—C5 | 1.3883 (19) |
O2—C9 | 1.2278 (16) | C4—H4 | 0.972 (16) |
N1—C9 | 1.3436 (17) | C5—C6 | 1.3776 (19) |
N1—C5 | 1.4399 (17) | C6—C7 | 1.391 (2) |
N1—C8 | 1.4569 (16) | C6—H6 | 0.966 (18) |
C1—H1C | 0.97 (2) | C7—H7 | 0.946 (18) |
C1—H1B | 1.04 (2) | C8—C9i | 1.4974 (19) |
C1—H1A | 0.96 (3) | C8—H8B | 0.974 (19) |
C2—C7 | 1.381 (2) | C8—H8A | 0.976 (18) |
C2—C3 | 1.389 (2) | C9—C8i | 1.4974 (19) |
C3—C4 | 1.375 (2) | | |
| | | |
C2—O1—C1 | 117.45 (14) | C6—C5—C4 | 119.57 (13) |
C9—N1—C5 | 120.56 (11) | C6—C5—N1 | 120.25 (12) |
C9—N1—C8 | 122.62 (11) | C4—C5—N1 | 120.11 (12) |
C5—N1—C8 | 116.67 (10) | C5—C6—C7 | 120.56 (14) |
O1—C1—H1C | 105.4 (13) | C5—C6—H6 | 118.9 (10) |
O1—C1—H1B | 109.7 (12) | C7—C6—H6 | 120.5 (10) |
H1C—C1—H1B | 113.3 (18) | C2—C7—C6 | 119.64 (14) |
O1—C1—H1A | 112.7 (15) | C2—C7—H7 | 121.4 (11) |
H1C—C1—H1A | 110 (2) | C6—C7—H7 | 119.0 (11) |
H1B—C1—H1A | 106.0 (19) | N1—C8—C9i | 118.06 (11) |
O1—C2—C7 | 124.48 (14) | N1—C8—H8B | 108.9 (10) |
O1—C2—C3 | 115.77 (13) | C9i—C8—H8B | 106.7 (10) |
C7—C2—C3 | 119.74 (14) | N1—C8—H8A | 109.5 (10) |
C4—C3—C2 | 120.40 (14) | C9i—C8—H8A | 106.3 (9) |
C4—C3—H3 | 120.4 (10) | H8B—C8—H8A | 106.8 (13) |
C2—C3—H3 | 119.2 (10) | O2—C9—N1 | 123.24 (12) |
C3—C4—C5 | 120.07 (14) | O2—C9—C8i | 117.51 (12) |
C3—C4—H4 | 120.9 (9) | N1—C9—C8i | 119.24 (11) |
C5—C4—H4 | 119.0 (9) | | |
| | | |
C1—O1—C2—C7 | −2.9 (3) | C4—C5—C6—C7 | −1.4 (2) |
C1—O1—C2—C3 | 175.98 (18) | N1—C5—C6—C7 | −178.39 (13) |
O1—C2—C3—C4 | −179.43 (15) | O1—C2—C7—C6 | 179.45 (14) |
C7—C2—C3—C4 | −0.5 (2) | C3—C2—C7—C6 | 0.6 (2) |
C2—C3—C4—C5 | −0.5 (2) | C5—C6—C7—C2 | 0.3 (2) |
C3—C4—C5—C6 | 1.5 (2) | C9—N1—C8—C9i | −3.3 (2) |
C3—C4—C5—N1 | 178.51 (13) | C5—N1—C8—C9i | 172.34 (11) |
C9—N1—C5—C6 | −126.95 (14) | C5—N1—C9—O2 | 7.0 (2) |
C8—N1—C5—C6 | 57.35 (17) | C8—N1—C9—O2 | −177.56 (13) |
C9—N1—C5—C4 | 56.05 (18) | C5—N1—C9—C8i | −172.13 (11) |
C8—N1—C5—C4 | −119.65 (14) | C8—N1—C9—C8i | 3.3 (2) |
Symmetry code: (i) −x+1, −y, −z+1. |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
C6—H6···O2ii | 0.97 (1) | 2.58 (1) | 3.510 (2) | 163 (1) |
C8—H8A···O2ii | 0.98 (1) | 2.42 (1) | 3.389 (1) | 174 (1) |
C8—H8B···O2iii | 0.97 (1) | 2.60 (1) | 3.090 (1) | 111 (1) |
Symmetry codes: (ii) x, y+1, z; (iii) x, −y−1/2, z−1/2. |