organic compounds
4,4′-(1,2-Diazaniumylethane-1,2-diyl)dibenzoate trihydrate
aDepartment of Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan
*Correspondence e-mail: akitsu@rs.kagu.tus.ac.jp
The title compound, C16H16N2O4·3H2O, was synthesized from (1R,2R)-1,2-bis(2-hydroxyphenyl)ethylenediamine and terephthalaldehydic acid. The compound crystallizes from water as a double zwitterion with protonated amine groups and deprotonated carboxylate groups. The dihedral angle formed by the aromatic rings is 3.86 (11)°. In the crystal, N—H⋯O and O—H⋯O hydrogen bonds link molecules into a three-dimensional network.
Keywords: crystal structure; double zwitterion; hydrogen bonds.
CCDC reference: 1452936
Structure description
In recent years, dyes that led to an improvement in efficiency of the current generation of dye-sensitized solar cells (DSSC) have been devised (Nazeeruddin et al., 1993; Hagfeldt et al., 2010; Brewster et al., 2013; Komatsu et al., 2013; Brown et al., 2013; Sinn et al., 2014). In our laboratory, we have been engaged in the study of chiral salen-type complexes as dyes containing carboxyl groups which can be adsorbed on the surface of TiO2, and with extended π-conjugated system in order to improve the power generation efficiency. During the course of this study, the title diamine compound as precursor of chiral salen-type ligands was synthesized, and its structure is reported herein. The molecule of the title compound crystallizes as a zwitterion with protonated amine groups NH3+ and deprotonated carboxylate groups COO− (Fig. 1). The C—O bonds lengths within the carboxylate groups range from 1.252 (4) to 1.262 (3) Å, indicating delocalization of the negative charge, and are in good agreement with those observed in the organic zwitterion 4-(ammoniomethyl)benzoate (Atria et al., 2014). The torsion angle C7—C8—C9—C10 is 178.8 (2)°. In the crystal, intermolecular N—H⋯O and O—H⋯O involving all ammonium groups, carboxylate groups and water molecules are observed, linking molecules into a three-dimensional network (Table 1).
Synthesis and crystallization
To a solution of (1R,2R)-bis(2-hydroxyphenyl)ethylendiamine (1.222 g, 5 mmol) dissolved in ethanol (17 ml) was added 4-formylbenzoic acid (1.801 g, 12 mmol). The resulting mixture was stirred at 298 K for 3 h to give a yellow precipitate of (I), which was washed with water (5 ml), filtered off and dried in a vacuum. To a clear solution of (I) in tetrahydrofuran (THF, 50 ml) was added acidified water (HCl, 3.0 ml, 37%), and the mixture was stirred at 300 K for 3 h. The white precipitate afforded was filtered and washed with THF to give analytically pure 4,4′-(1,2-diazaniumylethane-1,2-diyl)dibenzoate (yield: 1.046 g, 69.7%). The compound was recrystallized by slow evaporation from a water solution to give colourless prismatic single crystals. IR (KBr, cm−1): 421 (w), 505 (w), 540 (w), 606 (w), 667 (w), 743 (w), 777 (w), 863 (w), 977 (w), 1018 (w), 1078 (w), 1121 (m), 1181 (m), 1220 (m), 1384 (m), 1427 (w), 1469 (m), 1517 (m), 1572 (m), 1614 (m), 1697 (s, C=O), 2610 (m), 2976 (s), 3060 (s). MS (TOF–MASS) [M−] calculated for C16H15N2O4− = 299.10; found = 299.13.
Refinement
Crystal data, data collection and structure . The could not be determined unambigously as there was no significant using data collected with Mo radiation.
details are summarized in Table 2
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Structural data
CCDC reference: 1452936
https://doi.org/10.1107/S2414314616002522/rz4001sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314616002522/rz4001Isup2.hkl
Data collection: APEX2 (Bruker, 2013); cell
SAINT (Bruker, 2013); data reduction: SAINT (Bruker, 2013); program(s) used to solve structure: SHELXS2013 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).C16H16N2O4·3H2O | Z = 1 |
Mr = 354.35 | F(000) = 188 |
Triclinic, P1 | Dx = 1.422 Mg m−3 |
a = 6.778 (3) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 6.953 (3) Å | Cell parameters from 2325 reflections |
c = 9.458 (4) Å | θ = 2.3–27.5° |
α = 109.182 (6)° | µ = 0.11 mm−1 |
β = 93.369 (6)° | T = 173 K |
γ = 98.437 (6)° | Prism, colourless |
V = 413.7 (3) Å3 | 0.49 × 0.34 × 0.07 mm |
Bruker APEXII CCD diffractometer | 2030 independent reflections |
Radiation source: fine-forcus sealed tube | 1969 reflections with I > 2σ(I) |
Detector resolution: 8.333 pixels mm-1 | Rint = 0.019 |
φ and ω scans | θmax = 27.5°, θmin = 2.3° |
Absorption correction: multi-scan (SADABS; Bruker, 2013) | h = −8→8 |
Tmin = 0.946, Tmax = 0.990 | k = −8→9 |
2325 measured reflections | l = −12→6 |
Refinement on F2 | Hydrogen site location: mixed |
Least-squares matrix: full | H atoms treated by a mixture of independent and constrained refinement |
R[F2 > 2σ(F2)] = 0.038 | w = 1/[σ2(Fo2) + (0.0632P)2 + 0.1469P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.103 | (Δ/σ)max = 0.001 |
S = 1.03 | Δρmax = 0.37 e Å−3 |
2030 reflections | Δρmin = −0.21 e Å−3 |
253 parameters | Extinction correction: SHELXL2014 (Sheldrick 2015) |
3 restraints | Extinction coefficient: 0.061 (11) |
Primary atom site location: structure-invariant direct methods | Absolute structure: Flack x determined using 217 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013) |
Secondary atom site location: difference Fourier map | Absolute structure parameter: −0.2 (10) |
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. |
x | y | z | Uiso*/Ueq | ||
C2 | 0.2668 (4) | −0.0431 (4) | 0.0660 (3) | 0.0148 (5) | |
C14 | 0.6379 (4) | 0.5409 (4) | 1.0399 (3) | 0.0186 (6) | |
H14 | 0.7642 | 0.6159 | 1.0928 | 0.022* | |
C10 | 0.4424 (4) | 0.3099 (4) | 0.8089 (3) | 0.0150 (5) | |
C13 | 0.4672 (4) | 0.5516 (4) | 1.1153 (3) | 0.0154 (5) | |
C4 | 0.4811 (4) | 0.1770 (4) | 0.2925 (3) | 0.0165 (5) | |
H4 | 0.6097 | 0.2517 | 0.3405 | 0.02* | |
C15 | 0.6259 (4) | 0.4219 (4) | 0.8886 (3) | 0.0180 (5) | |
H15 | 0.7439 | 0.4169 | 0.8389 | 0.022* | |
C9 | 0.4215 (4) | 0.1817 (4) | 0.6422 (3) | 0.0155 (5) | |
H9 | 0.3206 | 0.054 | 0.6262 | 0.019* | |
C1 | 0.2389 (4) | −0.1709 (4) | −0.1001 (3) | 0.0177 (5) | |
C12 | 0.2827 (4) | 0.4406 (4) | 1.0366 (3) | 0.0166 (5) | |
H12 | 0.1651 | 0.4459 | 1.0866 | 0.02* | |
C8 | 0.3387 (4) | 0.2978 (4) | 0.5438 (3) | 0.0145 (5) | |
H8 | 0.2001 | 0.3148 | 0.5703 | 0.017* | |
C6 | 0.1036 (4) | −0.0325 (4) | 0.1485 (3) | 0.0189 (6) | |
H6 | −0.0263 | −0.1009 | 0.0992 | 0.023* | |
C5 | 0.1280 (4) | 0.0772 (4) | 0.3027 (3) | 0.0188 (6) | |
H5 | 0.0154 | 0.0814 | 0.3582 | 0.023* | |
C3 | 0.4556 (4) | 0.0630 (4) | 0.1388 (3) | 0.0156 (5) | |
H3 | 0.5681 | 0.0577 | 0.0831 | 0.019* | |
C16 | 0.4895 (4) | 0.6773 (4) | 1.2817 (3) | 0.0167 (5) | |
C11 | 0.2706 (4) | 0.3217 (4) | 0.8846 (3) | 0.0170 (5) | |
H11 | 0.1441 | 0.2476 | 0.8315 | 0.02* | |
C7 | 0.3178 (4) | 0.1811 (4) | 0.3758 (3) | 0.0151 (5) | |
O4 | 0.0625 (3) | −0.2489 (3) | −0.1609 (2) | 0.0281 (5) | |
O1 | 0.6571 (3) | 0.7863 (3) | 1.3418 (2) | 0.0245 (5) | |
O3 | 0.3929 (3) | −0.1941 (3) | −0.1665 (2) | 0.0240 (5) | |
O2 | 0.3413 (3) | 0.6659 (3) | 1.3551 (2) | 0.0223 (4) | |
O6 | 0.7705 (4) | 0.9702 (4) | 0.8108 (3) | 0.0346 (6) | |
O5 | 0.8755 (3) | 0.4606 (3) | 0.5889 (2) | 0.0230 (4) | |
O7 | 0.9441 (4) | 0.5415 (4) | 0.3428 (3) | 0.0338 (5) | |
N1 | 0.4571 (3) | 0.5128 (3) | 0.5815 (2) | 0.0161 (4) | |
H1A | 0.5904 | 0.5072 | 0.5822 | 0.024* | |
H1B | 0.4329 | 0.5936 | 0.674 | 0.024* | |
H1C | 0.4195 | 0.5676 | 0.5112 | 0.024* | |
N2 | 0.6159 (3) | 0.1137 (3) | 0.5979 (2) | 0.0162 (4) | |
H2A | 0.7043 | 0.2233 | 0.5941 | 0.024* | |
H2B | 0.5935 | 0.0126 | 0.5057 | 0.024* | |
H2C | 0.6677 | 0.064 | 0.6671 | 0.024* | |
H19 | 0.875 (7) | 0.639 (7) | 0.346 (5) | 0.050 (13)* | |
H18 | 1.071 (6) | 0.586 (5) | 0.333 (4) | 0.026 (9)* | |
H20 | 0.867 (8) | 0.900 (8) | 0.812 (6) | 0.057 (14)* | |
H17 | 0.903 (8) | 0.478 (8) | 0.507 (7) | 0.068 (16)* | |
H21 | 0.667 (8) | 0.937 (8) | 0.842 (6) | 0.057 (15)* | |
H16 | 0.951 (6) | 0.543 (7) | 0.664 (5) | 0.042 (11)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C2 | 0.0215 (12) | 0.0117 (12) | 0.0079 (11) | 0.0007 (10) | −0.0062 (9) | 0.0012 (9) |
C14 | 0.0207 (13) | 0.0203 (13) | 0.0111 (12) | −0.0028 (10) | −0.0045 (9) | 0.0044 (10) |
C10 | 0.0225 (13) | 0.0138 (12) | 0.0079 (12) | 0.0023 (10) | −0.0030 (9) | 0.0036 (9) |
C13 | 0.0209 (13) | 0.0143 (12) | 0.0112 (12) | 0.0017 (10) | −0.0029 (9) | 0.0058 (9) |
C4 | 0.0168 (12) | 0.0181 (13) | 0.0102 (12) | −0.0016 (10) | −0.0060 (9) | 0.0025 (9) |
C15 | 0.0186 (13) | 0.0217 (12) | 0.0121 (12) | 0.0000 (10) | −0.0009 (9) | 0.0056 (10) |
C9 | 0.0218 (12) | 0.0165 (12) | 0.0068 (11) | 0.0016 (10) | −0.0028 (9) | 0.0036 (9) |
C1 | 0.0261 (14) | 0.0130 (11) | 0.0107 (12) | 0.0028 (10) | −0.0067 (10) | 0.0014 (9) |
C12 | 0.0191 (13) | 0.0184 (12) | 0.0118 (12) | 0.0012 (10) | −0.0018 (9) | 0.0058 (10) |
C8 | 0.0141 (11) | 0.0162 (11) | 0.0085 (11) | −0.0018 (9) | −0.0051 (8) | 0.0012 (9) |
C6 | 0.0157 (12) | 0.0208 (13) | 0.0146 (13) | −0.0025 (10) | −0.0078 (10) | 0.0025 (10) |
C5 | 0.0181 (13) | 0.0213 (13) | 0.0122 (12) | −0.0016 (10) | −0.0026 (10) | 0.0023 (10) |
C3 | 0.0176 (12) | 0.0176 (12) | 0.0102 (12) | 0.0023 (10) | −0.0025 (9) | 0.0040 (9) |
C16 | 0.0226 (13) | 0.0163 (12) | 0.0116 (12) | 0.0049 (10) | −0.0041 (9) | 0.0056 (9) |
C11 | 0.0189 (12) | 0.0173 (12) | 0.0119 (12) | −0.0012 (10) | −0.0053 (10) | 0.0043 (10) |
C7 | 0.0183 (12) | 0.0156 (11) | 0.0098 (12) | 0.0019 (9) | −0.0049 (9) | 0.0039 (9) |
O4 | 0.0273 (10) | 0.0318 (11) | 0.0135 (10) | 0.0040 (8) | −0.0128 (8) | −0.0049 (8) |
O1 | 0.0239 (10) | 0.0266 (10) | 0.0143 (9) | 0.0012 (8) | −0.0055 (7) | −0.0017 (8) |
O3 | 0.0285 (10) | 0.0241 (10) | 0.0122 (9) | 0.0006 (8) | −0.0014 (8) | −0.0010 (7) |
O2 | 0.0245 (10) | 0.0304 (10) | 0.0128 (9) | 0.0078 (8) | 0.0013 (7) | 0.0072 (7) |
O6 | 0.0288 (12) | 0.0487 (15) | 0.0387 (13) | 0.0121 (11) | 0.0036 (10) | 0.0291 (11) |
O5 | 0.0235 (10) | 0.0246 (10) | 0.0129 (9) | −0.0058 (8) | −0.0052 (8) | 0.0012 (8) |
O7 | 0.0253 (12) | 0.0523 (14) | 0.0305 (12) | 0.0073 (11) | 0.0019 (9) | 0.0229 (10) |
N1 | 0.0210 (10) | 0.0164 (10) | 0.0089 (9) | 0.0013 (8) | −0.0033 (8) | 0.0034 (7) |
N2 | 0.0227 (10) | 0.0157 (9) | 0.0086 (9) | 0.0036 (8) | −0.0041 (7) | 0.0030 (8) |
C2—C6 | 1.387 (4) | C8—C7 | 1.516 (3) |
C2—C3 | 1.393 (3) | C8—H8 | 1.0 |
C2—C1 | 1.514 (3) | C6—C5 | 1.393 (4) |
C14—C13 | 1.393 (4) | C6—H6 | 0.95 |
C14—C15 | 1.389 (4) | C5—C7 | 1.396 (3) |
C14—H14 | 0.95 | C5—H5 | 0.95 |
C10—C15 | 1.394 (4) | C3—H3 | 0.95 |
C10—C11 | 1.401 (4) | C16—O1 | 1.255 (3) |
C10—C9 | 1.521 (3) | C16—O2 | 1.262 (3) |
C13—C12 | 1.394 (3) | C11—H11 | 0.95 |
C13—C16 | 1.514 (3) | O6—H20 | 0.88 (6) |
C4—C7 | 1.394 (4) | O6—H21 | 0.81 (6) |
C4—C3 | 1.395 (3) | O5—H17 | 0.85 (6) |
C4—H4 | 0.95 | O5—H16 | 0.83 (5) |
C15—H15 | 0.95 | O7—H19 | 0.87 (5) |
C9—N2 | 1.501 (4) | O7—H18 | 0.89 (4) |
C9—C8 | 1.549 (3) | N1—H1A | 0.91 |
C9—H9 | 1.0 | N1—H1B | 0.91 |
C1—O4 | 1.256 (3) | N1—H1C | 0.91 |
C1—O3 | 1.252 (4) | N2—H2A | 0.91 |
C12—C11 | 1.394 (4) | N2—H2B | 0.91 |
C12—H12 | 0.95 | N2—H2C | 0.91 |
C8—N1 | 1.507 (3) | ||
C6—C2—C3 | 119.0 (2) | C9—C8—H8 | 106.4 |
C6—C2—C1 | 120.1 (2) | C2—C6—C5 | 120.8 (2) |
C3—C2—C1 | 120.9 (2) | C2—C6—H6 | 119.6 |
C13—C14—C15 | 120.9 (2) | C5—C6—H6 | 119.6 |
C13—C14—H14 | 119.5 | C6—C5—C7 | 120.1 (2) |
C15—C14—H14 | 119.5 | C6—C5—H5 | 120.0 |
C15—C10—C11 | 118.5 (2) | C7—C5—H5 | 120.0 |
C15—C10—C9 | 122.3 (2) | C2—C3—C4 | 120.7 (2) |
C11—C10—C9 | 119.1 (2) | C2—C3—H3 | 119.7 |
C14—C13—C12 | 119.0 (2) | C4—C3—H3 | 119.7 |
C14—C13—C16 | 118.8 (2) | O1—C16—O2 | 122.6 (2) |
C12—C13—C16 | 122.1 (2) | O1—C16—C13 | 118.3 (2) |
C7—C4—C3 | 120.0 (2) | O2—C16—C13 | 119.1 (2) |
C7—C4—H4 | 120.0 | C12—C11—C10 | 120.9 (2) |
C3—C4—H4 | 120.0 | C12—C11—H11 | 119.5 |
C14—C15—C10 | 120.6 (2) | C10—C11—H11 | 119.5 |
C14—C15—H15 | 119.7 | C4—C7—C5 | 119.4 (2) |
C10—C15—H15 | 119.7 | C4—C7—C8 | 122.0 (2) |
N2—C9—C10 | 110.8 (2) | C5—C7—C8 | 118.6 (2) |
N2—C9—C8 | 112.81 (19) | H20—O6—H21 | 118 (5) |
C10—C9—C8 | 111.31 (19) | H17—O5—H16 | 113 (4) |
N2—C9—H9 | 107.2 | H19—O7—H18 | 109 (4) |
C10—C9—H9 | 107.2 | C8—N1—H1A | 109.5 |
C8—C9—H9 | 107.2 | C8—N1—H1B | 109.5 |
O4—C1—O3 | 124.7 (2) | H1A—N1—H1B | 109.5 |
O4—C1—C2 | 117.4 (2) | C8—N1—H1C | 109.5 |
O3—C1—C2 | 117.9 (2) | H1A—N1—H1C | 109.5 |
C11—C12—C13 | 120.1 (2) | H1B—N1—H1C | 109.5 |
C11—C12—H12 | 119.9 | C9—N2—H2A | 109.5 |
C13—C12—H12 | 119.9 | C9—N2—H2B | 109.5 |
N1—C8—C7 | 110.9 (2) | H2A—N2—H2B | 109.5 |
N1—C8—C9 | 111.91 (18) | C9—N2—H2C | 109.5 |
C7—C8—C9 | 114.34 (19) | H2A—N2—H2C | 109.5 |
N1—C8—H8 | 106.4 | H2B—N2—H2C | 109.5 |
C7—C8—H8 | 106.4 | ||
C15—C14—C13—C12 | 0.1 (4) | C1—C2—C6—C5 | 177.3 (2) |
C15—C14—C13—C16 | 177.8 (2) | C2—C6—C5—C7 | 1.1 (4) |
C13—C14—C15—C10 | −0.2 (4) | C6—C2—C3—C4 | 0.5 (4) |
C11—C10—C15—C14 | 0.6 (4) | C1—C2—C3—C4 | −178.6 (2) |
C9—C10—C15—C14 | 178.5 (2) | C7—C4—C3—C2 | 1.7 (4) |
C15—C10—C9—N2 | 26.1 (3) | C14—C13—C16—O1 | 8.0 (4) |
C11—C10—C9—N2 | −155.9 (2) | C12—C13—C16—O1 | −174.4 (2) |
C15—C10—C9—C8 | −100.3 (3) | C14—C13—C16—O2 | −170.7 (2) |
C11—C10—C9—C8 | 77.7 (3) | C12—C13—C16—O2 | 7.0 (4) |
C6—C2—C1—O4 | 6.4 (4) | C13—C12—C11—C10 | 0.6 (4) |
C3—C2—C1—O4 | −174.5 (2) | C15—C10—C11—C12 | −0.8 (4) |
C6—C2—C1—O3 | −172.6 (3) | C9—C10—C11—C12 | −178.8 (2) |
C3—C2—C1—O3 | 6.6 (4) | C3—C4—C7—C5 | −2.5 (4) |
C14—C13—C12—C11 | −0.3 (4) | C3—C4—C7—C8 | 178.3 (2) |
C16—C13—C12—C11 | −177.9 (2) | C6—C5—C7—C4 | 1.2 (4) |
N2—C9—C8—N1 | −73.5 (2) | C6—C5—C7—C8 | −179.6 (2) |
C10—C9—C8—N1 | 51.7 (3) | N1—C8—C7—C4 | 47.4 (3) |
N2—C9—C8—C7 | 53.6 (3) | C9—C8—C7—C4 | −80.3 (3) |
C10—C9—C8—C7 | 178.8 (2) | N1—C8—C7—C5 | −131.8 (2) |
C3—C2—C6—C5 | −1.9 (4) | C9—C8—C7—C5 | 100.6 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O5 | 0.91 | 2.01 | 2.911 (3) | 173 |
N1—H1B···O3i | 0.91 | 1.80 | 2.686 (3) | 165 |
N1—H1C···O2ii | 0.91 | 1.90 | 2.807 (3) | 176 |
N2—H2A···O5 | 0.91 | 1.89 | 2.798 (3) | 177 |
N2—H2B···O1iii | 0.91 | 1.93 | 2.787 (3) | 156 |
N2—H2C···O6iv | 0.91 | 1.83 | 2.744 (4) | 178 |
O7—H19···O1ii | 0.87 (5) | 1.92 (5) | 2.768 (4) | 162 (5) |
O7—H18···O2v | 0.89 (4) | 1.81 (4) | 2.688 (3) | 166 (4) |
O6—H20···O4vi | 0.87 (6) | 1.85 (6) | 2.720 (4) | 172 (5) |
O5—H17···O7 | 0.85 (7) | 1.77 (7) | 2.619 (4) | 172 (6) |
O6—H21···O3i | 0.81 (6) | 1.93 (5) | 2.696 (3) | 157 (5) |
O5—H16···O4vi | 0.84 (4) | 1.83 (4) | 2.654 (2) | 166 (4) |
Symmetry codes: (i) x, y+1, z+1; (ii) x, y, z−1; (iii) x, y−1, z−1; (iv) x, y−1, z; (v) x+1, y, z−1; (vi) x+1, y+1, z+1. |
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