The crystal structure of the title compound, C24H24N4O3, is dominated by one bifurcated intramolecular and two intermolecular hydrogen bonds. This demonstrates the flexible nature of the organic molecule and the strong tendency of carboxamide groups to form hydrogen bonds.
Supporting information
CCDC reference: 175994
Key indicators
- Single-crystal X-ray study
- T = 91 K
- Mean (C-C) = 0.006 Å
- R factor = 0.067
- wR factor = 0.239
- Data-to-parameter ratio = 31.6
checkCIF results
No syntax errors found
ADDSYM reports no extra symmetry
Alert Level A:
TYPE_049 Alert A _diffrn_reflns_number is not of type numb.
| Author response: I have given the number of reflections for each
of two twin components, separated by a comma.
|
REFLT_03
From the CIF: _diffrn_reflns_theta_max 30.50
From the CIF: _reflns_number_total 8879
TEST2: Reflns within _diffrn_reflns_theta_max
Count of symmetry unique reflns 6200
Completeness (_total/calc) 143.21%
Alert A: > 15% excess reflns - sys abs data present?
| Author response: The excess reflns represent the contributions from
the two twin components.
|
Alert Level B:
REFLT_01 Alert B The number of symmetry-independent reflections cannot
exceed the total number of reflections measured
Number of symmetry-independent reflections = 8879
Total number of reflections = 7955
| Author response: The total number of reflections is based on the unique
reflections for both twin components.
|
2 Alert Level A = Potentially serious problem
1 Alert Level B = Potential problem
0 Alert Level C = Please check
The title compound, (I), was synthesized via the coupling reaction of
nitrilotriacetic acid and aniline in the presence of triphenyl phosphite using
pyridine as the solvent. A mixture of 3.04 g of nitrilotriacetic acid (15.9 mmol), 4.44 g of aniline (47.7 mmol) and 14.81 g of triphenyl phosphite (47.7 mmol) in 25 ml of pyridine was heated to reflux for 4 h. The solvent was then
removed and a viscous brown oil remained. The resulting oil was dissolved in
chloroform and the solution was washed with small batches (3 × 10 ml) of
water. Pure (I) was obtained as a white powder following removal of the
chloroform solvent. Crystals of (I) were produced by diffusion of methanol
into the DMSO solution (yield 70%).
The compound crystallizes as well formed plates which all appear to suffer from
twinning no matter what solvent is used. A full sphere of data was collected
in the normal way. The structure could be solved from the data that was culled
from a good orientation matrix; however it was clear that much of the data was
being discarded. The initial model yielded a value of R1 = 0.174 with 4156
reflections [Fo > 4σ(Fo)]. Subsequently, the existence of rotationally
related twin components (a 180° rotation around 001) was confirmed using the
program GEMINI (Bruker, 1999). Integration was performed separately on
the two components. Several methods of combining the two sets of reflection
data were tried. For example, 6476 observed data, including partially
overlapped reflections, yielded a R1 value of 0.103. With partials omitted, a
value of R1 = 0.056 was obtained, but this resulted in only 1452 observed data
and a rather low data-to-parameter ratio; nevertheless the refinement was
quite stable. Finally, the data was sent to Michael Ruf at Bruker AXS, Inc,
who integrated it using a beta test version of SAINT (Bruker, 2001),
modified to handle multi-component integration. SAINT processes the
data simultaneously, determining profile shapes, updating matrices
independently. If spots start to overlap SAINT will combine the
overlapping integration boxes and do a simple summation. SAINT will not
use overlapping reflections for matrix refinement or statistics. The results
of this integration are the results being reported because the number of data
(8879 unique, 6786 observed) obtained is superior. The twin component is
0.357 (2). Cell parameters are based on the reflections of the major component.
Although the completeness is only 82% at the θmax of 30.5°, it is 97%
complete at θ of 30.0°.
Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Sheldrick, 1994); software used to prepare material for publication: SHELXL97.
Nitrilotriacetanilide
top
Crystal data top
C24H24N4O3 | Z = 2 |
Mr = 416.47 | F(000) = 440 |
Triclinic, P1 | Dx = 1.360 Mg m−3 |
a = 8.411 (2) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 8.819 (2) Å | Cell parameters from 999 reflections |
c = 14.886 (4) Å | θ = 2.5–31.1° |
α = 84.684 (6)° | µ = 0.09 mm−1 |
β = 82.425 (6)° | T = 91 K |
γ = 68.439 (6)° | Plate, colorless |
V = 1016.7 (4) Å3 | 0.48 × 0.28 × 0.04 mm |
Data collection top
Bruker SMART 1000 diffractometer | 6786 reflections with I > 2σ(I) |
Radiation source: normal-focus sealed tube | Rint = 0.060 |
Graphite monochromator | θmax = 30.5°, θmin = 2.5° |
Detector resolution: 8.3 pixels mm-1 | h = −11→11 |
ω scans | k = −12→12 |
7955,7827 measured reflections | l = −20→21 |
8879 independent reflections | |
Refinement top
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)] = 0.067 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.239 | H-atom parameters constrained |
S = 1.23 | w = 1/[σ2(Fo2) + (0.0619P)2 + 3.3081P] where P = (Fo2 + 2Fc2)/3 |
8879 reflections | (Δ/σ)max = 0.001 |
281 parameters | Δρmax = 0.59 e Å−3 |
0 restraints | Δρmin = −0.47 e Å−3 |
Crystal data top
C24H24N4O3 | γ = 68.439 (6)° |
Mr = 416.47 | V = 1016.7 (4) Å3 |
Triclinic, P1 | Z = 2 |
a = 8.411 (2) Å | Mo Kα radiation |
b = 8.819 (2) Å | µ = 0.09 mm−1 |
c = 14.886 (4) Å | T = 91 K |
α = 84.684 (6)° | 0.48 × 0.28 × 0.04 mm |
β = 82.425 (6)° | |
Data collection top
Bruker SMART 1000 diffractometer | 6786 reflections with I > 2σ(I) |
7955,7827 measured reflections | Rint = 0.060 |
8879 independent reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.067 | 0 restraints |
wR(F2) = 0.239 | H-atom parameters constrained |
S = 1.23 | Δρmax = 0.59 e Å−3 |
8879 reflections | Δρmin = −0.47 e Å−3 |
281 parameters | |
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 | 0.9631 (3) | 0.8152 (3) | 0.36205 (19) | 0.0216 (6) | |
O2 | 0.4162 (3) | 0.7777 (3) | 0.55058 (18) | 0.0183 (6) | |
O3 | 0.5423 (4) | 0.6546 (3) | 0.20056 (19) | 0.0210 (6) | |
N1 | 0.8131 (4) | 0.7963 (4) | 0.2485 (2) | 0.0166 (7) | |
H1 | 0.7138 | 0.7918 | 0.2391 | 0.020* | |
N2 | 0.1558 (4) | 0.8082 (4) | 0.5056 (2) | 0.0166 (6) | |
H2 | 0.0931 | 0.8385 | 0.4597 | 0.020* | |
N3 | 0.5089 (4) | 0.4272 (4) | 0.2757 (2) | 0.0154 (6) | |
H3 | 0.5055 | 0.3799 | 0.3303 | 0.018* | |
N4 | 0.5471 (4) | 0.7814 (3) | 0.3632 (2) | 0.0149 (6) | |
C1 | 0.6751 (5) | 0.8216 (5) | 0.4029 (2) | 0.0165 (7) | |
H1A | 0.7121 | 0.7464 | 0.4562 | 0.020* | |
H1B | 0.6224 | 0.9340 | 0.4244 | 0.020* | |
C2 | 0.8330 (5) | 0.8093 (4) | 0.3353 (3) | 0.0162 (7) | |
C3 | 0.9313 (5) | 0.7890 (4) | 0.1700 (3) | 0.0166 (8) | |
C4 | 1.0639 (5) | 0.8493 (5) | 0.1653 (3) | 0.0194 (8) | |
H4 | 1.0831 | 0.8931 | 0.2171 | 0.023* | |
C5 | 1.1674 (5) | 0.8448 (5) | 0.0844 (3) | 0.0229 (9) | |
H5 | 1.2585 | 0.8850 | 0.0813 | 0.027* | |
C6 | 1.1408 (5) | 0.7826 (5) | 0.0078 (3) | 0.0232 (9) | |
H6 | 1.2114 | 0.7822 | −0.0475 | 0.028* | |
C7 | 1.0093 (5) | 0.7208 (5) | 0.0132 (3) | 0.0240 (9) | |
H7 | 0.9911 | 0.6756 | −0.0383 | 0.029* | |
C8 | 0.9049 (5) | 0.7255 (5) | 0.0939 (3) | 0.0208 (8) | |
H8 | 0.8141 | 0.6847 | 0.0972 | 0.025* | |
C9 | 0.3682 (5) | 0.8678 (4) | 0.3951 (3) | 0.0168 (7) | |
H9A | 0.2947 | 0.8503 | 0.3534 | 0.020* | |
H9B | 0.3466 | 0.9861 | 0.3930 | 0.020* | |
C10 | 0.3155 (5) | 0.8141 (4) | 0.4920 (3) | 0.0158 (7) | |
C11 | 0.0814 (4) | 0.7566 (4) | 0.5885 (3) | 0.0161 (7) | |
C12 | −0.0152 (5) | 0.6591 (5) | 0.5836 (3) | 0.0188 (8) | |
H12 | −0.0329 | 0.6326 | 0.5263 | 0.023* | |
C13 | −0.0855 (5) | 0.6006 (5) | 0.6629 (3) | 0.0247 (9) | |
H13 | −0.1515 | 0.5343 | 0.6597 | 0.030* | |
C14 | −0.0596 (5) | 0.6388 (5) | 0.7459 (3) | 0.0240 (9) | |
H14 | −0.1056 | 0.5966 | 0.7999 | 0.029* | |
C15 | 0.0328 (5) | 0.7379 (5) | 0.7512 (3) | 0.0248 (9) | |
H15 | 0.0485 | 0.7651 | 0.8088 | 0.030* | |
C16 | 0.1030 (5) | 0.7984 (5) | 0.6726 (3) | 0.0192 (8) | |
H16 | 0.1653 | 0.8678 | 0.6764 | 0.023* | |
C17 | 0.5886 (5) | 0.6060 (4) | 0.3583 (3) | 0.0158 (7) | |
H17A | 0.5252 | 0.5669 | 0.4103 | 0.019* | |
H17B | 0.7131 | 0.5477 | 0.3622 | 0.019* | |
C18 | 0.5407 (5) | 0.5682 (4) | 0.2698 (3) | 0.0158 (7) | |
C19 | 0.4806 (4) | 0.3471 (4) | 0.2044 (3) | 0.0151 (7) | |
C20 | 0.4276 (5) | 0.4260 (5) | 0.1226 (3) | 0.0184 (8) | |
H20 | 0.4136 | 0.5377 | 0.1112 | 0.022* | |
C21 | 0.3950 (5) | 0.3413 (5) | 0.0574 (3) | 0.0191 (8) | |
H21 | 0.3608 | 0.3951 | 0.0010 | 0.023* | |
C22 | 0.4121 (5) | 0.1786 (5) | 0.0739 (3) | 0.0221 (8) | |
H22 | 0.3878 | 0.1219 | 0.0295 | 0.027* | |
C23 | 0.4649 (5) | 0.0997 (5) | 0.1558 (3) | 0.0224 (9) | |
H23 | 0.4780 | −0.0118 | 0.1672 | 0.027* | |
C24 | 0.4984 (5) | 0.1831 (5) | 0.2207 (3) | 0.0197 (8) | |
H24 | 0.5337 | 0.1287 | 0.2768 | 0.024* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
O1 | 0.0223 (14) | 0.0245 (14) | 0.0206 (14) | −0.0107 (12) | −0.0066 (11) | 0.0017 (13) |
O2 | 0.0201 (14) | 0.0192 (13) | 0.0153 (13) | −0.0073 (11) | −0.0027 (11) | 0.0021 (12) |
O3 | 0.0279 (15) | 0.0201 (14) | 0.0173 (14) | −0.0114 (12) | −0.0044 (11) | 0.0023 (12) |
N1 | 0.0130 (15) | 0.0197 (15) | 0.0164 (16) | −0.0051 (13) | −0.0027 (12) | 0.0016 (14) |
N2 | 0.0160 (15) | 0.0185 (15) | 0.0147 (15) | −0.0052 (13) | −0.0049 (12) | 0.0022 (14) |
N3 | 0.0183 (16) | 0.0159 (14) | 0.0127 (15) | −0.0074 (13) | −0.0021 (12) | 0.0013 (13) |
N4 | 0.0151 (15) | 0.0112 (13) | 0.0175 (15) | −0.0034 (12) | −0.0020 (12) | −0.0012 (13) |
C1 | 0.0206 (19) | 0.0178 (17) | 0.0119 (18) | −0.0077 (15) | −0.0021 (14) | −0.0006 (16) |
C2 | 0.0188 (18) | 0.0115 (15) | 0.0190 (19) | −0.0069 (14) | −0.0017 (14) | 0.0012 (15) |
C3 | 0.0170 (18) | 0.0138 (17) | 0.0152 (18) | −0.0028 (14) | −0.0006 (14) | 0.0043 (15) |
C4 | 0.0174 (18) | 0.0187 (18) | 0.021 (2) | −0.0056 (15) | −0.0010 (15) | 0.0000 (17) |
C5 | 0.0170 (19) | 0.0224 (19) | 0.029 (2) | −0.0075 (16) | −0.0027 (16) | 0.0012 (19) |
C6 | 0.0162 (19) | 0.027 (2) | 0.021 (2) | −0.0037 (16) | 0.0008 (15) | 0.0032 (18) |
C7 | 0.025 (2) | 0.028 (2) | 0.019 (2) | −0.0083 (18) | −0.0052 (16) | −0.0007 (18) |
C8 | 0.0197 (19) | 0.026 (2) | 0.021 (2) | −0.0126 (17) | −0.0037 (15) | 0.0013 (17) |
C9 | 0.0159 (18) | 0.0174 (17) | 0.0159 (18) | −0.0053 (15) | −0.0019 (14) | 0.0034 (15) |
C10 | 0.0191 (18) | 0.0099 (15) | 0.0163 (18) | −0.0035 (14) | 0.0000 (14) | −0.0004 (15) |
C11 | 0.0123 (17) | 0.0136 (16) | 0.0192 (19) | −0.0014 (14) | −0.0017 (14) | 0.0011 (16) |
C12 | 0.0141 (17) | 0.0175 (17) | 0.022 (2) | −0.0022 (14) | −0.0017 (15) | −0.0008 (17) |
C13 | 0.0156 (18) | 0.0202 (19) | 0.036 (3) | −0.0067 (16) | 0.0007 (17) | 0.0043 (19) |
C14 | 0.0166 (19) | 0.0220 (19) | 0.026 (2) | −0.0025 (16) | 0.0044 (16) | 0.0049 (19) |
C15 | 0.025 (2) | 0.0216 (19) | 0.023 (2) | −0.0036 (17) | 0.0016 (17) | −0.0012 (18) |
C16 | 0.0178 (18) | 0.0165 (17) | 0.022 (2) | −0.0052 (15) | −0.0004 (15) | −0.0013 (17) |
C17 | 0.0176 (18) | 0.0127 (16) | 0.0168 (19) | −0.0048 (14) | −0.0028 (14) | −0.0012 (15) |
C18 | 0.0132 (17) | 0.0165 (17) | 0.0165 (18) | −0.0039 (14) | −0.0005 (13) | −0.0023 (15) |
C19 | 0.0122 (17) | 0.0154 (17) | 0.0170 (18) | −0.0036 (14) | −0.0024 (13) | −0.0022 (15) |
C20 | 0.0172 (18) | 0.0194 (18) | 0.020 (2) | −0.0079 (16) | −0.0022 (14) | −0.0004 (16) |
C21 | 0.0188 (18) | 0.0241 (19) | 0.0154 (19) | −0.0086 (16) | −0.0034 (14) | 0.0007 (16) |
C22 | 0.0194 (19) | 0.0224 (19) | 0.024 (2) | −0.0051 (16) | −0.0039 (16) | −0.0086 (18) |
C23 | 0.020 (2) | 0.0135 (17) | 0.032 (2) | −0.0018 (15) | −0.0090 (17) | −0.0015 (18) |
C24 | 0.0194 (19) | 0.0173 (18) | 0.021 (2) | −0.0047 (15) | −0.0047 (15) | 0.0008 (16) |
Geometric parameters (Å, º) top
O1—C2 | 1.233 (4) | C9—C10 | 1.536 (5) |
O2—C10 | 1.234 (4) | C9—H9A | 0.9900 |
O3—C18 | 1.225 (4) | C9—H9B | 0.9900 |
N1—C2 | 1.345 (5) | C11—C16 | 1.389 (5) |
N1—C3 | 1.421 (5) | C11—C12 | 1.395 (5) |
N1—H1 | 0.8800 | C12—C13 | 1.391 (6) |
N2—C10 | 1.351 (5) | C12—H12 | 0.9500 |
N2—C11 | 1.422 (5) | C13—C14 | 1.373 (6) |
N2—H2 | 0.8800 | C13—H13 | 0.9500 |
N3—C18 | 1.357 (5) | C14—C15 | 1.380 (6) |
N3—C19 | 1.419 (5) | C14—H14 | 0.9500 |
N3—H3 | 0.8800 | C15—C16 | 1.391 (6) |
N4—C9 | 1.451 (5) | C15—H15 | 0.9500 |
N4—C1 | 1.457 (4) | C16—H16 | 0.9500 |
N4—C17 | 1.462 (4) | C17—C18 | 1.526 (5) |
C1—C2 | 1.533 (5) | C17—H17A | 0.9900 |
C1—H1A | 0.9900 | C17—H17B | 0.9900 |
C1—H1B | 0.9900 | C19—C20 | 1.387 (5) |
C3—C8 | 1.385 (5) | C19—C24 | 1.400 (5) |
C3—C4 | 1.393 (5) | C20—C21 | 1.389 (5) |
C4—C5 | 1.385 (6) | C20—H20 | 0.9500 |
C4—H4 | 0.9500 | C21—C22 | 1.390 (6) |
C5—C6 | 1.386 (6) | C21—H21 | 0.9500 |
C5—H5 | 0.9500 | C22—C23 | 1.388 (6) |
C6—C7 | 1.393 (6) | C22—H22 | 0.9500 |
C6—H6 | 0.9500 | C23—C24 | 1.382 (5) |
C7—C8 | 1.386 (6) | C23—H23 | 0.9500 |
C7—H7 | 0.9500 | C24—H24 | 0.9500 |
C8—H8 | 0.9500 | | |
| | | |
C2—N1—C3 | 128.5 (3) | N2—C10—C9 | 114.8 (3) |
C2—N1—H1 | 115.7 | C16—C11—C12 | 119.7 (4) |
C3—N1—H1 | 115.7 | C16—C11—N2 | 122.6 (3) |
C10—N2—C11 | 124.9 (3) | C12—C11—N2 | 117.7 (3) |
C10—N2—H2 | 117.5 | C13—C12—C11 | 119.9 (4) |
C11—N2—H2 | 117.5 | C13—C12—H12 | 120.0 |
C18—N3—C19 | 127.7 (3) | C11—C12—H12 | 120.0 |
C18—N3—H3 | 116.2 | C14—C13—C12 | 120.0 (4) |
C19—N3—H3 | 116.2 | C14—C13—H13 | 120.0 |
C9—N4—C1 | 116.9 (3) | C12—C13—H13 | 120.0 |
C9—N4—C17 | 112.8 (3) | C13—C14—C15 | 120.4 (4) |
C1—N4—C17 | 113.6 (3) | C13—C14—H14 | 119.8 |
N4—C1—C2 | 112.3 (3) | C15—C14—H14 | 119.8 |
N4—C1—H1A | 109.1 | C14—C15—C16 | 120.4 (4) |
C2—C1—H1A | 109.1 | C14—C15—H15 | 119.8 |
N4—C1—H1B | 109.1 | C16—C15—H15 | 119.8 |
C2—C1—H1B | 109.1 | C11—C16—C15 | 119.6 (4) |
H1A—C1—H1B | 107.9 | C11—C16—H16 | 120.2 |
O1—C2—N1 | 125.3 (4) | C15—C16—H16 | 120.2 |
O1—C2—C1 | 120.0 (4) | N4—C17—C18 | 110.8 (3) |
N1—C2—C1 | 114.7 (3) | N4—C17—H17A | 109.5 |
C8—C3—C4 | 119.7 (4) | C18—C17—H17A | 109.5 |
C8—C3—N1 | 117.0 (3) | N4—C17—H17B | 109.5 |
C4—C3—N1 | 123.2 (4) | C18—C17—H17B | 109.5 |
C5—C4—C3 | 119.2 (4) | H17A—C17—H17B | 108.1 |
C5—C4—H4 | 120.4 | O3—C18—N3 | 125.3 (4) |
C3—C4—H4 | 120.4 | O3—C18—C17 | 121.4 (3) |
C4—C5—C6 | 121.3 (4) | N3—C18—C17 | 113.1 (3) |
C4—C5—H5 | 119.3 | C20—C19—C24 | 119.4 (4) |
C6—C5—H5 | 119.3 | C20—C19—N3 | 123.1 (3) |
C5—C6—C7 | 119.1 (4) | C24—C19—N3 | 117.4 (3) |
C5—C6—H6 | 120.4 | C19—C20—C21 | 119.9 (4) |
C7—C6—H6 | 120.4 | C19—C20—H20 | 120.1 |
C8—C7—C6 | 119.8 (4) | C21—C20—H20 | 120.1 |
C8—C7—H7 | 120.1 | C22—C21—C20 | 120.6 (4) |
C6—C7—H7 | 120.1 | C22—C21—H21 | 119.7 |
C3—C8—C7 | 120.8 (4) | C20—C21—H21 | 119.7 |
C3—C8—H8 | 119.6 | C23—C22—C21 | 119.5 (4) |
C7—C8—H8 | 119.6 | C23—C22—H22 | 120.2 |
N4—C9—C10 | 113.8 (3) | C21—C22—H22 | 120.2 |
N4—C9—H9A | 108.8 | C24—C23—C22 | 120.1 (4) |
C10—C9—H9A | 108.8 | C24—C23—H23 | 120.0 |
N4—C9—H9B | 108.8 | C22—C23—H23 | 120.0 |
C10—C9—H9B | 108.8 | C23—C24—C19 | 120.5 (4) |
H9A—C9—H9B | 107.7 | C23—C24—H24 | 119.7 |
O2—C10—N2 | 124.5 (4) | C19—C24—H24 | 119.7 |
O2—C10—C9 | 120.7 (3) | | |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3···O2i | 0.88 | 2.17 | 3.012 (4) | 161 |
N2—H2···O1ii | 0.88 | 2.00 | 2.830 (4) | 158 |
N1—H1···O3 | 0.88 | 2.35 | 3.153 (4) | 153 |
N1—H1···N4 | 0.88 | 2.18 | 2.665 (5) | 114 |
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x−1, y, z. |
Experimental details
Crystal data |
Chemical formula | C24H24N4O3 |
Mr | 416.47 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 91 |
a, b, c (Å) | 8.411 (2), 8.819 (2), 14.886 (4) |
α, β, γ (°) | 84.684 (6), 82.425 (6), 68.439 (6) |
V (Å3) | 1016.7 (4) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.48 × 0.28 × 0.04 |
|
Data collection |
Diffractometer | Bruker SMART 1000 diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 7955,7827, 8879, 6786 |
Rint | 0.060 |
(sin θ/λ)max (Å−1) | 0.714 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.067, 0.239, 1.23 |
No. of reflections | 8879 |
No. of parameters | 281 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.59, −0.47 |
Selected bond lengths (Å) topO1—C2 | 1.233 (4) | N2—C11 | 1.422 (5) |
O2—C10 | 1.234 (4) | N3—C18 | 1.357 (5) |
O3—C18 | 1.225 (4) | N3—C19 | 1.419 (5) |
N1—C2 | 1.345 (5) | N4—C9 | 1.451 (5) |
N1—C3 | 1.421 (5) | N4—C1 | 1.457 (4) |
N2—C10 | 1.351 (5) | N4—C17 | 1.462 (4) |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3···O2i | 0.88 | 2.17 | 3.012 (4) | 161.4 |
N2—H2···O1ii | 0.88 | 2.00 | 2.830 (4) | 157.5 |
N1—H1···O3 | 0.88 | 2.35 | 3.153 (4) | 152.6 |
N1—H1···N4 | 0.88 | 2.18 | 2.665 (5) | 114.0 |
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x−1, y, z. |
The synthesis of new tripodal ligands with amidate groups that are based upon the tris(2-aminoethyl)amine unit has received attention in recent years due to their ability to complex Mn+ ions (Macbeth et al., 2000). Incorporation of amidate linkages within a tripodal ligand has also been utilized to develop tris-catecholate enterobactin analogues (Cohen et al., 2000). In addition, a variety of ligands designed to stabilize anion coordination are based in part on tripodal frames and utilize hydrogen-bond networks from amido groups to stabilize the ligand–anion interaction (Schmidtchen, 1997). The common synthetic route of coupling a carboxylic acid groups with primary amines via the use of triphenyl phosphite has been utilized here to afford the title compound, (I), in high yield.
The molecular structure of (I) is presented in Fig. 1. The three tripodal arms of the ligand are extended, in spite of the intramolecular hydrogen bonding involving the amide N1—H1 group and both N4 and O3. Additional hydrogen bonding is depicted in Fig. 2. The amide N3—H3 group forms a centrosymmetrically related pair of hydrogen bonds between H3 and O2'. The amide N2—H2 group hydrogen bonds to O1'' in a molecule translated along a.
It is interesting to note that the similar molecule tris[2-(benzoylamino)ethyl]amine, (II), has recently been reported (Goldcamp et al., 2000). In its structure, the molecule adopts a folded conformation that contrasts with the extended arrangement of (I) (Fig. 3). It also has an intramolecular hydrogen bond between a carboxamido N—H group of one arm of the tripodal ligand and a carbonyl O atom of a second carboxamide group. The difference in the tripodal unit of (II) compared to (I) is a simple rearrangement of the carboxamide units. Compound (II) is obtained from the reaction between tris(2-aminoethyl)amine and benzoic acid, while (I) is synthesized from nitrilotriacetic acid and aniline. The comparable intramolecular N—H···O hydrogen bond is part of an eight-membered ring in (I), while it is a ten-membered ring in (II). This slight change appears to have a profound effect on the structure of the resulting molecule, although other crystal-packing effects probably play a role. However, this may have implications in the development of molecular motifs that are specifically designed to stabilize a pre-formed molecular structure.