organic compounds
1,2-Bis(4-aminophenoxy)ethane
aDepartment of Chemistry, Quaid-I-Azam University, Islamabad 45320, Pakistan, and bInstitut für Anorganische Chemie, J. W. Goethe-Universität Frankfurt, Max-von-Laue-Strasse 7, 60438 Frankfurt/Main, Germany
*Correspondence e-mail: zareenakhter@yahoo.com
The molecule of the title compound, C14H16N2O2, is located on a crystallographic twofold rotation axis. The central O—C—C—O bridge adopts a gauche conformation. One of the amine H atoms is disordered over two equally occupied positions. The is stabilized by N—H⋯O and N—H⋯N hydrogen bonds.
Related literature
For related literature, see: Barikani & Mehdipour-Ataei (2000); Eastmond & Paprotny (1999); Hsio et al. (1997); Liaw & Liaw (2001); Yang & Chen (1993); Hergenrother et al. (2002).
Experimental
Crystal data
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Data collection
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Refinement
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Data collection: X-AREA (Stoe & Cie, 2001); cell X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL-Plus (Sheldrick, 2008); software used to prepare material for publication: PLATON (Spek, 2003).
Supporting information
10.1107/S1600536808014736/zl2110sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536808014736/zl2110Isup2.hkl
A two neck 250 ml round bottom flask was charged with 1 g of 1,2-di(p-nitrophenyloxy) ethylene (3.28 mmoles), 10 ml of hydrazine monohydrate, 80 ml of ethanol and 0.06 g of 5% palladium on carbon (Pd/C).The mixture was heated to reflux for 16 h and then filtered to remove Pd/C and the crude solid was recrystallized from ethanol to yield 92.2% of the diamine, m.p. 352K.
All H atoms could be located by difference Fourier synthesis but were ultimately placed in calculated positions using a riding model with C—H(aromatic) = 0.95 Å or C—H(methylene) = 0.99 Å with fixed individual displacement parameters [Uiso(H) = 1.2 Ueq(C). The amino H atoms were freely refined. One of the amino H atoms is disordered over two equally occupied positions.
Data collection: X-AREA (Stoe & Cie, 2001); cell
X-AREA (Stoe & Cie, 2001); data reduction: X-AREA (Stoe & Cie, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL-Plus (Sheldrick, 2008); software used to prepare material for publication: PLATON (Spek, 2003).C14H16N2O2 | Dx = 1.334 Mg m−3 |
Mr = 244.29 | Melting point: 179 K |
Orthorhombic, Pbcn | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2n 2ab | Cell parameters from 14232 reflections |
a = 14.2157 (9) Å | θ = 3.5–29.7° |
b = 10.4608 (8) Å | µ = 0.09 mm−1 |
c = 8.1817 (5) Å | T = 173 K |
V = 1216.68 (14) Å3 | Block, dark red |
Z = 4 | 0.37 × 0.35 × 0.23 mm |
F(000) = 520 |
Stoe IPDSII two-circle diffractometer | 1549 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.049 |
Graphite monochromator | θmax = 29.6°, θmin = 3.5° |
ω scans | h = −19→19 |
15103 measured reflections | k = −14→11 |
1700 independent reflections | l = −11→11 |
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)] = 0.048 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.119 | w = 1/[σ2(Fo2) + (0.0299P)2 + 0.7945P] where P = (Fo2 + 2Fc2)/3 |
S = 1.20 | (Δ/σ)max < 0.001 |
1700 reflections | Δρmax = 0.29 e Å−3 |
95 parameters | Δρmin = −0.19 e Å−3 |
0 restraints | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.024 (2) |
C14H16N2O2 | V = 1216.68 (14) Å3 |
Mr = 244.29 | Z = 4 |
Orthorhombic, Pbcn | Mo Kα radiation |
a = 14.2157 (9) Å | µ = 0.09 mm−1 |
b = 10.4608 (8) Å | T = 173 K |
c = 8.1817 (5) Å | 0.37 × 0.35 × 0.23 mm |
Stoe IPDSII two-circle diffractometer | 1549 reflections with I > 2σ(I) |
15103 measured reflections | Rint = 0.049 |
1700 independent reflections |
R[F2 > 2σ(F2)] = 0.048 | 0 restraints |
wR(F2) = 0.119 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.20 | Δρmax = 0.29 e Å−3 |
1700 reflections | Δρmin = −0.19 e Å−3 |
95 parameters |
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 | Occ. (<1) | |
O1 | 0.91391 (6) | 0.60429 (10) | 0.65677 (12) | 0.0243 (3) | |
N1 | 0.52550 (9) | 0.65323 (15) | 0.5428 (2) | 0.0332 (3) | |
H1A | 0.5093 (15) | 0.718 (2) | 0.470 (3) | 0.048 (6)* | |
H1B | 0.496 (3) | 0.573 (4) | 0.537 (5) | 0.042 (11)* | 0.50 |
H1C | 0.486 (3) | 0.650 (4) | 0.638 (6) | 0.048 (12)* | 0.50 |
C1 | 0.81695 (9) | 0.61092 (12) | 0.63296 (15) | 0.0198 (3) | |
C2 | 0.78489 (9) | 0.71034 (13) | 0.53437 (17) | 0.0232 (3) | |
H2 | 0.8285 | 0.7684 | 0.4872 | 0.028* | |
C3 | 0.68899 (10) | 0.72479 (13) | 0.50483 (17) | 0.0239 (3) | |
H3 | 0.6678 | 0.7931 | 0.4377 | 0.029* | |
C4 | 0.62345 (9) | 0.64020 (13) | 0.57255 (17) | 0.0234 (3) | |
C5 | 0.65662 (10) | 0.54140 (14) | 0.67195 (19) | 0.0268 (3) | |
H5 | 0.6131 | 0.4835 | 0.7196 | 0.032* | |
C6 | 0.75275 (10) | 0.52624 (13) | 0.70255 (17) | 0.0240 (3) | |
H6 | 0.7742 | 0.4586 | 0.7704 | 0.029* | |
C7 | 0.94691 (9) | 0.49765 (13) | 0.75075 (18) | 0.0244 (3) | |
H7A | 0.9230 | 0.4169 | 0.7033 | 0.029* | |
H7B | 0.9237 | 0.5043 | 0.8645 | 0.029* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0192 (4) | 0.0272 (5) | 0.0264 (5) | −0.0010 (4) | −0.0026 (4) | 0.0063 (4) |
N1 | 0.0205 (6) | 0.0377 (7) | 0.0413 (8) | 0.0012 (5) | −0.0023 (5) | 0.0043 (6) |
C1 | 0.0202 (6) | 0.0214 (6) | 0.0178 (5) | −0.0003 (5) | −0.0017 (4) | −0.0017 (5) |
C2 | 0.0231 (6) | 0.0230 (6) | 0.0235 (6) | −0.0010 (5) | 0.0019 (5) | 0.0039 (5) |
C3 | 0.0246 (6) | 0.0239 (6) | 0.0233 (6) | 0.0036 (5) | −0.0001 (5) | 0.0028 (5) |
C4 | 0.0205 (6) | 0.0254 (6) | 0.0244 (6) | 0.0005 (5) | −0.0010 (5) | −0.0028 (5) |
C5 | 0.0228 (6) | 0.0267 (6) | 0.0310 (7) | −0.0048 (5) | −0.0004 (5) | 0.0043 (6) |
C6 | 0.0247 (6) | 0.0223 (6) | 0.0250 (6) | −0.0023 (5) | −0.0033 (5) | 0.0050 (5) |
C7 | 0.0237 (6) | 0.0233 (6) | 0.0261 (6) | −0.0007 (5) | −0.0050 (5) | 0.0024 (5) |
O1—C1 | 1.3938 (15) | C3—C4 | 1.3992 (19) |
O1—C7 | 1.4338 (16) | C3—H3 | 0.9500 |
N1—C4 | 1.4202 (18) | C4—C5 | 1.397 (2) |
N1—H1A | 0.93 (2) | C5—C6 | 1.3983 (19) |
N1—H1B | 0.94 (4) | C5—H5 | 0.9500 |
N1—H1C | 0.96 (5) | C6—H6 | 0.9500 |
C1—C2 | 1.3928 (18) | C7—C7i | 1.510 (2) |
C1—C6 | 1.3935 (18) | C7—H7A | 0.9900 |
C2—C3 | 1.3927 (18) | C7—H7B | 0.9900 |
C2—H2 | 0.9500 | ||
C1—O1—C7 | 115.93 (10) | C5—C4—C3 | 118.27 (12) |
C4—N1—H1A | 115.0 (14) | C5—C4—N1 | 120.12 (13) |
C4—N1—H1B | 112 (3) | C3—C4—N1 | 121.61 (13) |
H1A—N1—H1B | 120 (3) | C4—C5—C6 | 121.20 (12) |
C4—N1—H1C | 115 (3) | C4—C5—H5 | 119.4 |
H1A—N1—H1C | 114 (3) | C6—C5—H5 | 119.4 |
H1B—N1—H1C | 75 (3) | C1—C6—C5 | 119.65 (12) |
C2—C1—C6 | 119.80 (12) | C1—C6—H6 | 120.2 |
C2—C1—O1 | 116.21 (11) | C5—C6—H6 | 120.2 |
C6—C1—O1 | 123.98 (12) | O1—C7—C7i | 108.83 (10) |
C3—C2—C1 | 120.12 (12) | O1—C7—H7A | 109.9 |
C3—C2—H2 | 119.9 | C7i—C7—H7A | 109.9 |
C1—C2—H2 | 119.9 | O1—C7—H7B | 109.9 |
C2—C3—C4 | 120.96 (12) | C7i—C7—H7B | 109.9 |
C2—C3—H3 | 119.5 | H7A—C7—H7B | 108.3 |
C4—C3—H3 | 119.5 | ||
C7—O1—C1—C2 | −176.63 (12) | C3—C4—C5—C6 | −0.5 (2) |
C7—O1—C1—C6 | 4.11 (19) | N1—C4—C5—C6 | 179.72 (14) |
C6—C1—C2—C3 | −0.3 (2) | C2—C1—C6—C5 | 0.4 (2) |
O1—C1—C2—C3 | −179.57 (12) | O1—C1—C6—C5 | 179.62 (13) |
C1—C2—C3—C4 | −0.2 (2) | C4—C5—C6—C1 | 0.0 (2) |
C2—C3—C4—C5 | 0.6 (2) | C1—O1—C7—C7i | 174.05 (12) |
C2—C3—C4—N1 | −179.62 (14) |
Symmetry code: (i) −x+2, y, −z+3/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O1ii | 0.93 (2) | 2.53 (2) | 3.4082 (18) | 158.6 (18) |
N1—H1B···N1iii | 0.94 (4) | 2.48 (4) | 3.360 (3) | 157 (4) |
N1—H1C···N1iv | 0.96 (5) | 2.61 (5) | 3.468 (3) | 148 (3) |
Symmetry codes: (ii) x−1/2, −y+3/2, −z+1; (iii) −x+1, −y+1, −z+1; (iv) −x+1, y, −z+3/2. |
Experimental details
Crystal data | |
Chemical formula | C14H16N2O2 |
Mr | 244.29 |
Crystal system, space group | Orthorhombic, Pbcn |
Temperature (K) | 173 |
a, b, c (Å) | 14.2157 (9), 10.4608 (8), 8.1817 (5) |
V (Å3) | 1216.68 (14) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.37 × 0.35 × 0.23 |
Data collection | |
Diffractometer | Stoe IPDSII two-circle diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 15103, 1700, 1549 |
Rint | 0.049 |
(sin θ/λ)max (Å−1) | 0.695 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.048, 0.119, 1.20 |
No. of reflections | 1700 |
No. of parameters | 95 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.29, −0.19 |
Computer programs: X-AREA (Stoe & Cie, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP in SHELXTL-Plus (Sheldrick, 2008), PLATON (Spek, 2003).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O1i | 0.93 (2) | 2.53 (2) | 3.4082 (18) | 158.6 (18) |
N1—H1B···N1ii | 0.94 (4) | 2.48 (4) | 3.360 (3) | 157 (4) |
N1—H1C···N1iii | 0.96 (5) | 2.61 (5) | 3.468 (3) | 148 (3) |
Symmetry codes: (i) x−1/2, −y+3/2, −z+1; (ii) −x+1, −y+1, −z+1; (iii) −x+1, y, −z+3/2. |
Acknowledgements
The authors are grateful to the Department of Chemistry, Quaid-I-Azam University, Islamabad, Pakistan, and to the Institute for Inorganic Chemistry, University of Frankfurt, Germany, for providing laboratory and analytical facilities.
References
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Aromatic polyimides are well accepted as high performance and heat resistant materials (Hergenrother et al., 2000). They exhibit a favorable balance of physical and chemical properties, show excellent thermal, mechanical and electrical properties and are thus widely used in microelectronics and aerospace engineering (Eastmond & Paprotny, 1999). However, the technological and industrial application of rigid polyimides are limited by processing difficulties due to their high melting or glass transition temperatures and their lack of solubility in most organic solvents (Hsio et al., 1997). Strong interactions between polyimide chains and their rigid structures are the main reason for these behaviors. To overcome such a drawback, different methods have been introduced to modifiy their structures. Many efforts have been made in designing and synthesizing new dianhydrides (Eastmond & Paprotny, 1999) and diamines (Yang & Chen, 1993), and therefore producing a great variety of more soluble and processable polyimides for various purposes and applications. Incorporation of flexible units such as –NHCO–, –O–, (Barikani & Mehdipour-Ataei, 2000), –CO– and –SO2- is one of the most important approaches to overcome these processing problems (Liaw & Liaw, 2001). The title compound is such a new starting material for the synthesis of high performance polyimides.
Molecules of the title compound, C14H16N2O4, are located on a crystallographic twofold rotation axis. The central O—C—C—O bridge adopts a gauche conformation. One of the amino H atoms is disordered over two equally occupied positions. As a result of that, neighbouring molecules are connected by alternating hydrogen bonds, either N1-H1B···N1ii or N1-H1C···N1iii, because H1B and H1C and their symmetry equivalents would be too close to each other and would be mutually exclusive (symmetry codes: see Table 1). In addition, the crystal structure is stabilized by N—H···O hydrogen bonds (Table 1).