organic compounds
2,4,6-Triphenylaniline
aDepartment of Chemistry and Biochemistry, Center for Nanoscience, University of Missouri-St. Louis, St. Louis, Missouri, USA
*Correspondence e-mail: beattya@umsl.edu
Individual molecules of the title compound, C24H19N, do not participate in hydrogen-bonding interactions due to the steric bulk of the phenyl rings ortho to the amine. The dihedral angles between the central ring and the pendant rings are 68.26 (10), 55.28 (10) and 30.61 (11)°.
Related literature
The reaction of equimolar amounts of pyrazole-3,5-dicarboxylic acid (HPzDCA) and primary et al. (2009); Beatty et al. (2002a,b). For other that do not exhibit intermolecular hydrogen bonding due to the bulky ortho phenyl groups, see: Cherian et al. (2005); Lonkin & Marshal (2004). For the preparation of 2,4,6-triphenylaniline, see: Basu et al. (2003); Paul & Clark (2003).
have yielded ammonium carboxylate salts that adopt layered architectures, see: UgonoExperimental
Crystal data
|
Data collection: APEX2 (Bruker, 2007); cell SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009).
Supporting information
10.1107/S160053681002338X/hg2686sup1.cif
contains datablocks I, New_Global_Publ_Block. DOI:Structure factors: contains datablock I. DOI: 10.1107/S160053681002338X/hg2686Isup2.hkl
Into a 20 ml scintillation vial was placed 65 mg (37 mmol s) of pyrazole-3,5-dicarboxylic acid, 120 mg (37 mmol s) of 2,4,6-triphenylaniline (Basu et al., 2003; Paul & Clark, 2003) and 5 ml of a 3:2 ethanol:water mixture. The mixture was warmed gently until the solution became clear and then filtered. The filtrate was placed in another scintillation vial, and colorless single crystals of the title compound were obtained in 48 h.
All non hydrogen atoms were refined anisotropically. Phenyl hydrogen atoms were placed in calculated positions and treated with a riding model C–H= 0.95 Å, Uiso(Haryl)= 1.2Ueq(C) for aromatic carbons. Amine hydrogen atoms were also placed in calulated positions and treated with a riding model N–H= 0.88 Å, Uiso(Hamine)= 1.2Ueq(N).
Data collection: APEX2 (Bruker, 2007); cell
SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).C24H19N | F(000) = 680 |
Mr = 321.40 | Dx = 1.226 Mg m−3 |
Monoclinic, P21/c | Melting point = 395–398 K |
Hall symbol: -P 2ybc | Mo Kα radiation, λ = 0.71073 Å |
a = 10.735 (2) Å | Cell parameters from 6695 reflections |
b = 14.792 (3) Å | θ = 2.1–33.9° |
c = 11.911 (2) Å | µ = 0.07 mm−1 |
β = 113.02 (3)° | T = 100 K |
V = 1740.7 (6) Å3 | Prism, colorless |
Z = 4 | 0.50 × 0.50 × 0.25 mm |
Bruker SMART APEXII diffractometer | 6695 independent reflections |
Radiation source: fine-focus sealed tube | 5813 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.027 |
ω scans | θmax = 33.9°, θmin = 2.1° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −16→16 |
Tmin = 0.966, Tmax = 0.983 | k = −23→23 |
44061 measured reflections | l = −18→18 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.043 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.125 | H-atom parameters constrained |
S = 1.02 | w = 1/[σ2(Fo2) + (0.0697P)2 + 0.5511P] where P = (Fo2 + 2Fc2)/3 |
6695 reflections | (Δ/σ)max = 0.001 |
226 parameters | Δρmax = 0.48 e Å−3 |
0 restraints | Δρmin = −0.23 e Å−3 |
C24H19N | V = 1740.7 (6) Å3 |
Mr = 321.40 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 10.735 (2) Å | µ = 0.07 mm−1 |
b = 14.792 (3) Å | T = 100 K |
c = 11.911 (2) Å | 0.50 × 0.50 × 0.25 mm |
β = 113.02 (3)° |
Bruker SMART APEXII diffractometer | 6695 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 5813 reflections with I > 2σ(I) |
Tmin = 0.966, Tmax = 0.983 | Rint = 0.027 |
44061 measured reflections |
R[F2 > 2σ(F2)] = 0.043 | 0 restraints |
wR(F2) = 0.125 | H-atom parameters constrained |
S = 1.02 | Δρmax = 0.48 e Å−3 |
6695 reflections | Δρmin = −0.23 e Å−3 |
226 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 | ||
N1 | −0.03946 (8) | 0.31892 (6) | 0.10628 (7) | 0.02312 (15) | |
H1A | −0.0309 | 0.3532 | 0.1693 | 0.028* | |
H1B | −0.1086 | 0.2817 | 0.0760 | 0.028* | |
C1 | 0.05584 (7) | 0.32362 (5) | 0.05479 (6) | 0.01365 (13) | |
C2 | 0.16729 (8) | 0.38320 (5) | 0.10276 (7) | 0.01385 (13) | |
C3 | 0.26324 (8) | 0.38694 (5) | 0.05077 (7) | 0.01493 (13) | |
H3 | 0.3376 | 0.4272 | 0.0842 | 0.018* | |
C4 | 0.25338 (7) | 0.33322 (5) | −0.04924 (7) | 0.01409 (13) | |
C5 | 0.14616 (7) | 0.27160 (5) | −0.09177 (7) | 0.01405 (13) | |
H5 | 0.1399 | 0.2322 | −0.1567 | 0.017* | |
C6 | 0.04796 (7) | 0.26577 (5) | −0.04244 (6) | 0.01310 (13) | |
C7 | 0.18451 (8) | 0.44422 (5) | 0.20775 (7) | 0.01407 (13) | |
C8 | 0.29191 (8) | 0.43079 (5) | 0.32071 (7) | 0.01645 (14) | |
H8 | 0.3517 | 0.3812 | 0.3314 | 0.020* | |
C9 | 0.31156 (8) | 0.48981 (6) | 0.41751 (7) | 0.01874 (15) | |
H9 | 0.3837 | 0.4796 | 0.4941 | 0.022* | |
C10 | 0.22601 (9) | 0.56362 (6) | 0.40238 (7) | 0.01889 (15) | |
H10 | 0.2404 | 0.6042 | 0.4681 | 0.023* | |
C11 | 0.11933 (9) | 0.57760 (6) | 0.29049 (7) | 0.01905 (15) | |
H11 | 0.0609 | 0.6280 | 0.2797 | 0.023* | |
C12 | 0.09793 (9) | 0.51788 (5) | 0.19407 (7) | 0.01751 (14) | |
H12 | 0.0239 | 0.5273 | 0.1184 | 0.021* | |
C13 | 0.34837 (8) | 0.34425 (5) | −0.11131 (7) | 0.01444 (13) | |
C14 | 0.48238 (8) | 0.37311 (6) | −0.04755 (7) | 0.01809 (14) | |
H14 | 0.5146 | 0.3829 | 0.0380 | 0.022* | |
C15 | 0.56863 (8) | 0.38749 (6) | −0.10796 (8) | 0.02019 (15) | |
H15 | 0.6589 | 0.4071 | −0.0633 | 0.024* | |
C16 | 0.52351 (9) | 0.37333 (6) | −0.23338 (8) | 0.02020 (15) | |
H16 | 0.5819 | 0.3842 | −0.2747 | 0.024* | |
C17 | 0.39142 (9) | 0.34296 (6) | −0.29744 (8) | 0.01904 (15) | |
H17 | 0.3603 | 0.3318 | −0.3826 | 0.023* | |
C18 | 0.30489 (8) | 0.32897 (5) | −0.23725 (7) | 0.01613 (14) | |
H18 | 0.2150 | 0.3088 | −0.2821 | 0.019* | |
C19 | −0.06390 (7) | 0.19929 (5) | −0.09729 (6) | 0.01294 (12) | |
C20 | −0.19933 (8) | 0.22763 (5) | −0.14897 (7) | 0.01598 (14) | |
H20 | −0.2206 | 0.2894 | −0.1433 | 0.019* | |
C21 | −0.30318 (8) | 0.16641 (5) | −0.20861 (7) | 0.01793 (14) | |
H21 | −0.3944 | 0.1866 | −0.2431 | 0.022* | |
C22 | −0.27334 (8) | 0.07567 (5) | −0.21765 (7) | 0.01761 (14) | |
H22 | −0.3438 | 0.0339 | −0.2587 | 0.021* | |
C23 | −0.13918 (8) | 0.04676 (5) | −0.16595 (7) | 0.01747 (14) | |
H23 | −0.1184 | −0.0151 | −0.1715 | 0.021* | |
C24 | −0.03506 (8) | 0.10781 (5) | −0.10612 (7) | 0.01537 (13) | |
H24 | 0.0559 | 0.0872 | −0.0712 | 0.018* |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0255 (3) | 0.0285 (4) | 0.0204 (3) | −0.0110 (3) | 0.0144 (3) | −0.0100 (3) |
C1 | 0.0160 (3) | 0.0130 (3) | 0.0116 (3) | −0.0006 (2) | 0.0051 (2) | 0.0004 (2) |
C2 | 0.0169 (3) | 0.0120 (3) | 0.0117 (3) | −0.0010 (2) | 0.0047 (2) | −0.0007 (2) |
C3 | 0.0165 (3) | 0.0133 (3) | 0.0141 (3) | −0.0019 (2) | 0.0050 (2) | −0.0016 (2) |
C4 | 0.0147 (3) | 0.0134 (3) | 0.0139 (3) | −0.0009 (2) | 0.0053 (2) | −0.0010 (2) |
C5 | 0.0153 (3) | 0.0124 (3) | 0.0139 (3) | −0.0006 (2) | 0.0052 (2) | −0.0015 (2) |
C6 | 0.0146 (3) | 0.0112 (3) | 0.0123 (3) | −0.0006 (2) | 0.0040 (2) | −0.0001 (2) |
C7 | 0.0177 (3) | 0.0130 (3) | 0.0113 (3) | −0.0022 (2) | 0.0054 (2) | −0.0006 (2) |
C8 | 0.0166 (3) | 0.0180 (3) | 0.0134 (3) | −0.0012 (2) | 0.0045 (2) | −0.0003 (2) |
C9 | 0.0196 (3) | 0.0231 (4) | 0.0123 (3) | −0.0046 (3) | 0.0049 (3) | −0.0016 (3) |
C10 | 0.0253 (4) | 0.0192 (3) | 0.0140 (3) | −0.0058 (3) | 0.0095 (3) | −0.0039 (3) |
C11 | 0.0268 (4) | 0.0151 (3) | 0.0165 (3) | 0.0002 (3) | 0.0098 (3) | −0.0012 (2) |
C12 | 0.0229 (3) | 0.0148 (3) | 0.0132 (3) | 0.0011 (3) | 0.0052 (3) | 0.0004 (2) |
C13 | 0.0153 (3) | 0.0125 (3) | 0.0155 (3) | −0.0007 (2) | 0.0060 (2) | −0.0011 (2) |
C14 | 0.0154 (3) | 0.0195 (3) | 0.0182 (3) | −0.0013 (2) | 0.0054 (3) | −0.0018 (3) |
C15 | 0.0159 (3) | 0.0192 (3) | 0.0262 (4) | −0.0002 (3) | 0.0090 (3) | −0.0002 (3) |
C16 | 0.0214 (4) | 0.0173 (3) | 0.0264 (4) | 0.0023 (3) | 0.0142 (3) | 0.0026 (3) |
C17 | 0.0245 (4) | 0.0166 (3) | 0.0186 (3) | 0.0012 (3) | 0.0112 (3) | 0.0001 (3) |
C18 | 0.0181 (3) | 0.0144 (3) | 0.0158 (3) | −0.0012 (2) | 0.0065 (3) | −0.0017 (2) |
C19 | 0.0153 (3) | 0.0117 (3) | 0.0117 (3) | −0.0009 (2) | 0.0052 (2) | 0.0001 (2) |
C20 | 0.0162 (3) | 0.0129 (3) | 0.0166 (3) | 0.0004 (2) | 0.0041 (2) | 0.0001 (2) |
C21 | 0.0162 (3) | 0.0162 (3) | 0.0178 (3) | −0.0010 (2) | 0.0028 (3) | 0.0006 (2) |
C22 | 0.0189 (3) | 0.0152 (3) | 0.0167 (3) | −0.0041 (2) | 0.0048 (3) | −0.0012 (2) |
C23 | 0.0204 (3) | 0.0123 (3) | 0.0204 (3) | −0.0017 (2) | 0.0088 (3) | −0.0018 (2) |
C24 | 0.0168 (3) | 0.0124 (3) | 0.0176 (3) | −0.0007 (2) | 0.0075 (3) | −0.0006 (2) |
N1—C1 | 1.3850 (11) | C12—H12 | 0.9500 |
N1—H1A | 0.8800 | C13—C18 | 1.4040 (11) |
N1—H1B | 0.8800 | C13—C14 | 1.4050 (11) |
C1—C2 | 1.4142 (11) | C14—C15 | 1.3933 (12) |
C1—C6 | 1.4156 (10) | C14—H14 | 0.9500 |
C2—C3 | 1.3951 (11) | C15—C16 | 1.3944 (13) |
C2—C7 | 1.4939 (11) | C15—H15 | 0.9500 |
C3—C4 | 1.4010 (11) | C16—C17 | 1.3960 (13) |
C3—H3 | 0.9500 | C16—H16 | 0.9500 |
C4—C5 | 1.3987 (10) | C17—C18 | 1.3930 (12) |
C4—C13 | 1.4841 (11) | C17—H17 | 0.9500 |
C5—C6 | 1.3959 (11) | C18—H18 | 0.9500 |
C5—H5 | 0.9500 | C19—C24 | 1.4012 (11) |
C6—C19 | 1.4907 (10) | C19—C20 | 1.4030 (11) |
C7—C12 | 1.3997 (11) | C20—C21 | 1.3958 (11) |
C7—C8 | 1.4020 (12) | C20—H20 | 0.9500 |
C8—C9 | 1.3950 (11) | C21—C22 | 1.3939 (12) |
C8—H8 | 0.9500 | C21—H21 | 0.9500 |
C9—C10 | 1.3923 (13) | C22—C23 | 1.3938 (12) |
C9—H9 | 0.9500 | C22—H22 | 0.9500 |
C10—C11 | 1.3916 (13) | C23—C24 | 1.3962 (11) |
C10—H10 | 0.9500 | C23—H23 | 0.9500 |
C11—C12 | 1.3949 (11) | C24—H24 | 0.9500 |
C11—H11 | 0.9500 | ||
C1—N1—H1A | 120.0 | C7—C12—H12 | 119.7 |
C1—N1—H1B | 120.0 | C18—C13—C14 | 117.95 (8) |
H1A—N1—H1B | 120.0 | C18—C13—C4 | 120.56 (7) |
N1—C1—C2 | 120.47 (7) | C14—C13—C4 | 121.46 (7) |
N1—C1—C6 | 120.92 (7) | C15—C14—C13 | 120.93 (8) |
C2—C1—C6 | 118.53 (7) | C15—C14—H14 | 119.5 |
C3—C2—C1 | 120.01 (7) | C13—C14—H14 | 119.5 |
C3—C2—C7 | 118.45 (7) | C14—C15—C16 | 120.51 (8) |
C1—C2—C7 | 121.53 (7) | C14—C15—H15 | 119.7 |
C2—C3—C4 | 122.11 (7) | C16—C15—H15 | 119.7 |
C2—C3—H3 | 118.9 | C15—C16—C17 | 119.14 (8) |
C4—C3—H3 | 118.9 | C15—C16—H16 | 120.4 |
C5—C4—C3 | 117.09 (7) | C17—C16—H16 | 120.4 |
C5—C4—C13 | 121.31 (7) | C18—C17—C16 | 120.38 (8) |
C3—C4—C13 | 121.54 (7) | C18—C17—H17 | 119.8 |
C6—C5—C4 | 122.53 (7) | C16—C17—H17 | 119.8 |
C6—C5—H5 | 118.7 | C17—C18—C13 | 121.06 (8) |
C4—C5—H5 | 118.7 | C17—C18—H18 | 119.5 |
C5—C6—C1 | 119.59 (7) | C13—C18—H18 | 119.5 |
C5—C6—C19 | 117.89 (6) | C24—C19—C20 | 118.49 (7) |
C1—C6—C19 | 122.51 (7) | C24—C19—C6 | 120.41 (7) |
C12—C7—C8 | 118.77 (7) | C20—C19—C6 | 120.94 (7) |
C12—C7—C2 | 120.91 (7) | C21—C20—C19 | 120.92 (7) |
C8—C7—C2 | 120.26 (7) | C21—C20—H20 | 119.5 |
C9—C8—C7 | 120.42 (8) | C19—C20—H20 | 119.5 |
C9—C8—H8 | 119.8 | C22—C21—C20 | 120.14 (7) |
C7—C8—H8 | 119.8 | C22—C21—H21 | 119.9 |
C10—C9—C8 | 120.33 (8) | C20—C21—H21 | 119.9 |
C10—C9—H9 | 119.8 | C23—C22—C21 | 119.36 (7) |
C8—C9—H9 | 119.8 | C23—C22—H22 | 120.3 |
C11—C10—C9 | 119.64 (7) | C21—C22—H22 | 120.3 |
C11—C10—H10 | 120.2 | C22—C23—C24 | 120.65 (7) |
C9—C10—H10 | 120.2 | C22—C23—H23 | 119.7 |
C10—C11—C12 | 120.22 (8) | C24—C23—H23 | 119.7 |
C10—C11—H11 | 119.9 | C23—C24—C19 | 120.44 (7) |
C12—C11—H11 | 119.9 | C23—C24—H24 | 119.8 |
C11—C12—C7 | 120.61 (8) | C19—C24—H24 | 119.8 |
C11—C12—H12 | 119.7 |
Experimental details
Crystal data | |
Chemical formula | C24H19N |
Mr | 321.40 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 100 |
a, b, c (Å) | 10.735 (2), 14.792 (3), 11.911 (2) |
β (°) | 113.02 (3) |
V (Å3) | 1740.7 (6) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.07 |
Crystal size (mm) | 0.50 × 0.50 × 0.25 |
Data collection | |
Diffractometer | Bruker SMART APEXII diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.966, 0.983 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 44061, 6695, 5813 |
Rint | 0.027 |
(sin θ/λ)max (Å−1) | 0.784 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.043, 0.125, 1.02 |
No. of reflections | 6695 |
No. of parameters | 226 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.48, −0.23 |
Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), X-SEED (Barbour, 2001), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).
Acknowledgements
The authors are grateful to the Center for Nanoscience at the University of Missouri-St Louis for access to the single-crystal X-ray facility.
References
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The reactions of equimolar amounts of pyrazole-3,5-dicarboxylic acid (HPzDCA) and primary amines have yielded ammonium carboxylate salts that adopt layered architectures (Ugono et al., 2009; Beatty et al., 2002a,b). The level of structural fidelity for these organic salts allows, from a crystal engineering point of view, for the tuning of material properties by changing the identity of the organic group for the amines employed in the reaction. The reaction of pyrazole-3,5-dicarboxylic acid and 2,4,6-triphenylaniline (TPA) does not produce appreciable amounts of the desired ammonium carboxylate salt. However, large colorless single crystals of the aniline were obtained and structurally characterized.
The title compound packs in the monoclinic space group P 21/c, with one molecule in the asymmetric unit. TPA does not self aggregate via intermolecular hydrogen bonds in the solid state. This lack of significant intermolecular hydrogen bonds appears to be due to the bulky ortho phenyl groups. These groups ensure that the distance requirements for hydrogen bond interactions are not satisfied, as potential participating hydrogen bonding donors and acceptors can not approach each other. This is not uncommon, as other amines, namely 2,6-bis(Benzofuran-2-yl)phenylamine (Lonkin et al., 2004) and (R,R)-2,6-bis(1-Phenylethyl)4-methylaniline (Cherian et al., 2005) among others, exhibit this characteristic for identical reasons.