organic compounds
3-[Bis(dimethylamino)methylene]-1,1-diphenylurea
aFakultät Chemie/Organische Chemie, Hochschule Aalen, Beethovenstrasse 1, D-73430 Aalen, Germany
*Correspondence e-mail: Ioannis.Tiritiris@htw-aalen.de
In the title compound, C18H22N4O, the C=N and C—N bond lengths in the CN3 unit are 1.3179 (11), 1.3551 (11) and 1.3737 (11) Å, indicating double- and single-bond character, respectively. The N—C—N angles are 115.91 (8), 118.20 (8) and 125.69 (8), showing a deviation of the CN3 plane from an ideal trigonal–planar geometry. The bonds between the N atoms and the terminal C-methyl groups all have values close to a typical single bond [1.4529 (12)–1.4624 (12) Å]. The dihedral angle between the phenyl rings is 79.63 (4)°. In the crystal, the molecules are connected via weak C—H⋯O hydrogen bonds, generating chains along [100].
Related literature
For synthesis of N-dimethylcarbamoyl-N′,N′,N′′,N′′-tetramethylguanidine, see: Möllers et al. (2003). For the crystal structures of 2- and 5-azido-N-(diphenylcarbamoyl) proline methyl ester, see: Lynch et al. (1995).
Experimental
Crystal data
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Data collection
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Refinement
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Data collection: APEX2 (Bruker, 2008); cell SAINT (Bruker, 2008); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Putz, 2005); software used to prepare material for publication: SHELXL97.
Supporting information
10.1107/S160053681204127X/im2403sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S160053681204127X/im2403Isup2.hkl
Supporting information file. DOI: 10.1107/S160053681204127X/im2403Isup3.cml
The title compound was obtained by heating two equivalents (60.4 mmol) of N',N',N'',N''-tetramethylguanidine with one equivalent (30.2 mmol) N,N-diphenylcarbamoyl chloride in acetonitrile for three hours under reflux. After cooling to room temperature the precipitated N',N',N'',N''-tetramethylguanidinium chloride was filtered off and the solvent was removed. The residue was redissolved in diethylether and the insoluble part was filtered off. After evaporation of the solvent a colorless solid was been obtained. The title compound crystallized from a saturated acetonitrile solution after several days at 273 K, forming colorless single crystals. Yield: 7.6 g (81%)
The hydrogen atoms of the methyl groups were allowed to rotate with a fixed angle around the C–N bond to best fit the experimental electron density, with Uiso(H) set to 1.5 Ueq(C) and d(C—H) = 0.98 Å. H atoms of the aromatic rings were placed in calculated positions with (C—H) = 0.95 Å. They were included in the
using the riding model approximation, with Uiso(H) set to 1.2 Ueq(C).Data collection: APEX2 (Bruker, 2008); cell
SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Putz, 2005); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).C18H22N4O | F(000) = 664 |
Mr = 310.40 | Dx = 1.262 Mg m−3 |
Monoclinic, P21/c | Melting point: 427 K |
Hall symbol: -P 2ybc | Mo Kα radiation, λ = 0.71073 Å |
a = 7.9321 (3) Å | Cell parameters from 4990 reflections |
b = 17.0477 (9) Å | θ = 2.1–30.5° |
c = 12.2151 (6) Å | µ = 0.08 mm−1 |
β = 98.583 (2)° | T = 100 K |
V = 1633.28 (13) Å3 | Block, colorless |
Z = 4 | 0.25 × 0.20 × 0.15 mm |
Bruker Kappa APEXII Duo diffractometer | 4200 reflections with I > 2σ(I) |
Radiation source: sealed tube | Rint = 0.029 |
Graphite monochromator | θmax = 30.5°, θmin = 2.1° |
ϕ scans, and ω scans | h = −11→11 |
51490 measured reflections | k = −24→24 |
4990 independent reflections | l = −17→16 |
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)] = 0.039 | Hydrogen site location: difference Fourier map |
wR(F2) = 0.105 | H-atom parameters constrained |
S = 1.04 | w = 1/[σ2(Fo2) + (0.0541P)2 + 0.4544P] where P = (Fo2 + 2Fc2)/3 |
4990 reflections | (Δ/σ)max < 0.001 |
212 parameters | Δρmax = 0.37 e Å−3 |
0 restraints | Δρmin = −0.23 e Å−3 |
C18H22N4O | V = 1633.28 (13) Å3 |
Mr = 310.40 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 7.9321 (3) Å | µ = 0.08 mm−1 |
b = 17.0477 (9) Å | T = 100 K |
c = 12.2151 (6) Å | 0.25 × 0.20 × 0.15 mm |
β = 98.583 (2)° |
Bruker Kappa APEXII Duo diffractometer | 4200 reflections with I > 2σ(I) |
51490 measured reflections | Rint = 0.029 |
4990 independent reflections |
R[F2 > 2σ(F2)] = 0.039 | 0 restraints |
wR(F2) = 0.105 | H-atom parameters constrained |
S = 1.04 | Δρmax = 0.37 e Å−3 |
4990 reflections | Δρmin = −0.23 e Å−3 |
212 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 | ||
C1 | 0.37589 (11) | 0.11725 (5) | 0.29192 (7) | 0.01420 (17) | |
N1 | 0.44747 (10) | 0.12889 (5) | 0.40021 (7) | 0.01682 (16) | |
C2 | 0.63269 (12) | 0.12487 (6) | 0.43072 (8) | 0.0215 (2) | |
H2A | 0.6820 | 0.0965 | 0.3733 | 0.032* | |
H2B | 0.6606 | 0.0973 | 0.5015 | 0.032* | |
H2C | 0.6796 | 0.1781 | 0.4379 | 0.032* | |
C3 | 0.36063 (13) | 0.17835 (6) | 0.47145 (8) | 0.02078 (19) | |
H3A | 0.3971 | 0.2329 | 0.4654 | 0.031* | |
H3B | 0.3893 | 0.1608 | 0.5484 | 0.031* | |
H3C | 0.2371 | 0.1746 | 0.4485 | 0.031* | |
N2 | 0.41847 (10) | 0.04945 (4) | 0.24502 (7) | 0.01680 (16) | |
C4 | 0.47540 (14) | −0.02051 (6) | 0.30890 (9) | 0.0239 (2) | |
H4A | 0.4702 | −0.0110 | 0.3874 | 0.036* | |
H4B | 0.5930 | −0.0327 | 0.2992 | 0.036* | |
H4C | 0.4013 | −0.0648 | 0.2829 | 0.036* | |
C5 | 0.36459 (14) | 0.03644 (6) | 0.12745 (8) | 0.0218 (2) | |
H5A | 0.2532 | 0.0104 | 0.1162 | 0.033* | |
H5B | 0.4483 | 0.0032 | 0.0982 | 0.033* | |
H5C | 0.3560 | 0.0869 | 0.0886 | 0.033* | |
N3 | 0.26184 (10) | 0.16304 (4) | 0.23400 (7) | 0.01607 (16) | |
C6 | 0.27494 (11) | 0.24288 (5) | 0.24670 (7) | 0.01419 (16) | |
O1 | 0.40355 (8) | 0.28089 (4) | 0.28186 (6) | 0.01803 (14) | |
N4 | 0.12115 (10) | 0.28111 (4) | 0.20749 (7) | 0.01481 (15) | |
C7 | −0.02172 (11) | 0.23987 (5) | 0.14776 (7) | 0.01345 (16) | |
C8 | −0.00729 (12) | 0.20271 (5) | 0.04806 (7) | 0.01524 (17) | |
H8A | 0.0983 | 0.2033 | 0.0202 | 0.018* | |
C9 | −0.14748 (12) | 0.16466 (5) | −0.01074 (8) | 0.01697 (18) | |
H9A | −0.1369 | 0.1387 | −0.0782 | 0.020* | |
C10 | −0.30287 (12) | 0.16456 (5) | 0.02879 (8) | 0.01796 (18) | |
H10A | −0.3989 | 0.1392 | −0.0120 | 0.022* | |
C11 | −0.31730 (12) | 0.20166 (5) | 0.12827 (8) | 0.01758 (18) | |
H11A | −0.4232 | 0.2014 | 0.1557 | 0.021* | |
C12 | −0.17678 (12) | 0.23931 (5) | 0.18795 (8) | 0.01584 (17) | |
H12A | −0.1869 | 0.2645 | 0.2560 | 0.019* | |
C13 | 0.10260 (11) | 0.36346 (5) | 0.22264 (7) | 0.01373 (16) | |
C14 | 0.01332 (12) | 0.40811 (5) | 0.13736 (8) | 0.01772 (18) | |
H14A | −0.0281 | 0.3842 | 0.0683 | 0.021* | |
C15 | −0.01532 (13) | 0.48785 (5) | 0.15331 (9) | 0.0216 (2) | |
H15A | −0.0774 | 0.5178 | 0.0952 | 0.026* | |
C16 | 0.04600 (13) | 0.52374 (5) | 0.25311 (9) | 0.0221 (2) | |
H16A | 0.0259 | 0.5779 | 0.2638 | 0.026* | |
C17 | 0.13735 (13) | 0.47939 (5) | 0.33744 (8) | 0.02066 (19) | |
H17A | 0.1811 | 0.5038 | 0.4057 | 0.025* | |
C18 | 0.16545 (12) | 0.39969 (5) | 0.32295 (8) | 0.01654 (18) | |
H18 | 0.2274 | 0.3700 | 0.3813 | 0.020* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0131 (4) | 0.0118 (4) | 0.0181 (4) | −0.0006 (3) | 0.0039 (3) | 0.0001 (3) |
N1 | 0.0154 (4) | 0.0174 (3) | 0.0175 (4) | 0.0034 (3) | 0.0019 (3) | −0.0007 (3) |
C2 | 0.0164 (4) | 0.0251 (5) | 0.0222 (5) | 0.0006 (4) | −0.0001 (3) | 0.0032 (4) |
C3 | 0.0236 (5) | 0.0201 (4) | 0.0195 (4) | 0.0025 (4) | 0.0061 (4) | −0.0027 (3) |
N2 | 0.0200 (4) | 0.0120 (3) | 0.0186 (4) | 0.0032 (3) | 0.0038 (3) | 0.0001 (3) |
C4 | 0.0307 (5) | 0.0137 (4) | 0.0288 (5) | 0.0067 (4) | 0.0097 (4) | 0.0038 (4) |
C5 | 0.0283 (5) | 0.0174 (4) | 0.0201 (4) | −0.0012 (4) | 0.0047 (4) | −0.0049 (3) |
N3 | 0.0155 (4) | 0.0105 (3) | 0.0212 (4) | 0.0007 (3) | −0.0005 (3) | −0.0004 (3) |
C6 | 0.0143 (4) | 0.0125 (4) | 0.0158 (4) | 0.0007 (3) | 0.0021 (3) | −0.0006 (3) |
O1 | 0.0147 (3) | 0.0144 (3) | 0.0244 (3) | −0.0018 (2) | 0.0008 (3) | −0.0017 (2) |
N4 | 0.0140 (3) | 0.0094 (3) | 0.0201 (4) | 0.0000 (3) | −0.0005 (3) | −0.0019 (3) |
C7 | 0.0143 (4) | 0.0092 (3) | 0.0163 (4) | −0.0005 (3) | 0.0004 (3) | 0.0005 (3) |
C8 | 0.0158 (4) | 0.0138 (4) | 0.0166 (4) | 0.0002 (3) | 0.0041 (3) | 0.0000 (3) |
C9 | 0.0213 (4) | 0.0140 (4) | 0.0151 (4) | −0.0003 (3) | 0.0011 (3) | −0.0010 (3) |
C10 | 0.0174 (4) | 0.0132 (4) | 0.0222 (4) | −0.0021 (3) | −0.0008 (3) | 0.0004 (3) |
C11 | 0.0146 (4) | 0.0157 (4) | 0.0229 (4) | −0.0009 (3) | 0.0044 (3) | 0.0018 (3) |
C12 | 0.0176 (4) | 0.0133 (4) | 0.0170 (4) | 0.0005 (3) | 0.0040 (3) | −0.0005 (3) |
C13 | 0.0132 (4) | 0.0100 (4) | 0.0187 (4) | −0.0005 (3) | 0.0045 (3) | −0.0005 (3) |
C14 | 0.0174 (4) | 0.0137 (4) | 0.0213 (4) | 0.0006 (3) | 0.0002 (3) | 0.0002 (3) |
C15 | 0.0199 (4) | 0.0131 (4) | 0.0309 (5) | 0.0027 (3) | 0.0011 (4) | 0.0035 (4) |
C16 | 0.0214 (5) | 0.0116 (4) | 0.0344 (5) | 0.0012 (3) | 0.0080 (4) | −0.0028 (4) |
C17 | 0.0242 (5) | 0.0155 (4) | 0.0233 (5) | −0.0017 (3) | 0.0070 (4) | −0.0055 (3) |
C18 | 0.0196 (4) | 0.0138 (4) | 0.0169 (4) | −0.0008 (3) | 0.0050 (3) | −0.0004 (3) |
C1—N3 | 1.3179 (11) | N4—C7 | 1.4367 (11) |
C1—N2 | 1.3551 (11) | C7—C12 | 1.3907 (13) |
C1—N1 | 1.3737 (11) | C7—C8 | 1.3925 (12) |
N1—C3 | 1.4566 (12) | C8—C9 | 1.3909 (12) |
N1—C2 | 1.4624 (12) | C8—H8A | 0.9500 |
C2—H2A | 0.9800 | C9—C10 | 1.3893 (14) |
C2—H2B | 0.9800 | C9—H9A | 0.9500 |
C2—H2C | 0.9800 | C10—C11 | 1.3897 (14) |
C3—H3A | 0.9800 | C10—H10A | 0.9500 |
C3—H3B | 0.9800 | C11—C12 | 1.3940 (13) |
C3—H3C | 0.9800 | C11—H11A | 0.9500 |
N2—C5 | 1.4529 (12) | C12—H12A | 0.9500 |
N2—C4 | 1.4594 (12) | C13—C14 | 1.3949 (12) |
C4—H4A | 0.9800 | C13—C18 | 1.3961 (12) |
C4—H4B | 0.9800 | C14—C15 | 1.3967 (13) |
C4—H4C | 0.9800 | C14—H14A | 0.9500 |
C5—H5A | 0.9800 | C15—C16 | 1.3857 (15) |
C5—H5B | 0.9800 | C15—H15A | 0.9500 |
C5—H5C | 0.9800 | C16—C17 | 1.3910 (14) |
N3—C6 | 1.3722 (11) | C16—H16A | 0.9500 |
C6—O1 | 1.2305 (11) | C17—C18 | 1.3923 (12) |
C6—N4 | 1.4028 (11) | C17—H17A | 0.9500 |
N4—C13 | 1.4266 (11) | C18—H18 | 0.9500 |
N3—C1—N2 | 118.20 (8) | C6—N4—C7 | 121.73 (7) |
N3—C1—N1 | 125.69 (8) | C13—N4—C7 | 117.30 (7) |
N2—C1—N1 | 115.91 (8) | C12—C7—C8 | 119.87 (8) |
C1—N1—C3 | 119.63 (8) | C12—C7—N4 | 119.75 (8) |
C1—N1—C2 | 119.59 (8) | C8—C7—N4 | 120.34 (8) |
C3—N1—C2 | 114.93 (8) | C9—C8—C7 | 120.00 (9) |
N1—C2—H2A | 109.5 | C9—C8—H8A | 120.0 |
N1—C2—H2B | 109.5 | C7—C8—H8A | 120.0 |
H2A—C2—H2B | 109.5 | C10—C9—C8 | 120.24 (8) |
N1—C2—H2C | 109.5 | C10—C9—H9A | 119.9 |
H2A—C2—H2C | 109.5 | C8—C9—H9A | 119.9 |
H2B—C2—H2C | 109.5 | C9—C10—C11 | 119.76 (8) |
N1—C3—H3A | 109.5 | C9—C10—H10A | 120.1 |
N1—C3—H3B | 109.5 | C11—C10—H10A | 120.1 |
H3A—C3—H3B | 109.5 | C10—C11—C12 | 120.20 (9) |
N1—C3—H3C | 109.5 | C10—C11—H11A | 119.9 |
H3A—C3—H3C | 109.5 | C12—C11—H11A | 119.9 |
H3B—C3—H3C | 109.5 | C7—C12—C11 | 119.92 (8) |
C1—N2—C5 | 119.54 (8) | C7—C12—H12A | 120.0 |
C1—N2—C4 | 123.21 (8) | C11—C12—H12A | 120.0 |
C5—N2—C4 | 115.19 (8) | C14—C13—C18 | 119.28 (8) |
N2—C4—H4A | 109.5 | C14—C13—N4 | 119.39 (8) |
N2—C4—H4B | 109.5 | C18—C13—N4 | 121.27 (8) |
H4A—C4—H4B | 109.5 | C13—C14—C15 | 120.13 (9) |
N2—C4—H4C | 109.5 | C13—C14—H14A | 119.9 |
H4A—C4—H4C | 109.5 | C15—C14—H14A | 119.9 |
H4B—C4—H4C | 109.5 | C16—C15—C14 | 120.62 (9) |
N2—C5—H5A | 109.5 | C16—C15—H15A | 119.7 |
N2—C5—H5B | 109.5 | C14—C15—H15A | 119.7 |
H5A—C5—H5B | 109.5 | C15—C16—C17 | 119.15 (9) |
N2—C5—H5C | 109.5 | C15—C16—H16A | 120.4 |
H5A—C5—H5C | 109.5 | C17—C16—H16A | 120.4 |
H5B—C5—H5C | 109.5 | C16—C17—C18 | 120.79 (9) |
C1—N3—C6 | 119.50 (8) | C16—C17—H17A | 119.6 |
O1—C6—N3 | 127.35 (8) | C18—C17—H17A | 119.6 |
O1—C6—N4 | 120.53 (8) | C17—C18—C13 | 120.02 (9) |
N3—C6—N4 | 112.02 (7) | C17—C18—H18 | 120.0 |
C6—N4—C13 | 120.94 (7) | C13—C18—H18 | 120.0 |
N3—C1—N1—C3 | 21.15 (14) | C12—C7—C8—C9 | −0.43 (13) |
N2—C1—N1—C3 | −153.60 (9) | N4—C7—C8—C9 | −178.31 (8) |
N3—C1—N1—C2 | −130.58 (10) | C7—C8—C9—C10 | 0.95 (13) |
N2—C1—N1—C2 | 54.67 (12) | C8—C9—C10—C11 | −0.94 (13) |
N3—C1—N2—C5 | 11.89 (13) | C9—C10—C11—C12 | 0.41 (14) |
N1—C1—N2—C5 | −172.95 (8) | C8—C7—C12—C11 | −0.09 (13) |
N3—C1—N2—C4 | −151.00 (9) | N4—C7—C12—C11 | 177.79 (8) |
N1—C1—N2—C4 | 24.16 (13) | C10—C11—C12—C7 | 0.11 (13) |
N2—C1—N3—C6 | −146.79 (9) | C6—N4—C13—C14 | 140.27 (9) |
N1—C1—N3—C6 | 38.57 (14) | C7—N4—C13—C14 | −37.84 (12) |
C1—N3—C6—O1 | 22.08 (15) | C6—N4—C13—C18 | −42.63 (13) |
C1—N3—C6—N4 | −161.69 (8) | C7—N4—C13—C18 | 139.26 (9) |
O1—C6—N4—C13 | −9.58 (13) | C18—C13—C14—C15 | −1.21 (14) |
N3—C6—N4—C13 | 173.89 (8) | N4—C13—C14—C15 | 175.95 (9) |
O1—C6—N4—C7 | 168.45 (8) | C13—C14—C15—C16 | 0.78 (15) |
N3—C6—N4—C7 | −8.08 (12) | C14—C15—C16—C17 | 0.25 (15) |
C6—N4—C7—C12 | 121.44 (9) | C15—C16—C17—C18 | −0.84 (15) |
C13—N4—C7—C12 | −60.46 (11) | C16—C17—C18—C13 | 0.40 (15) |
C6—N4—C7—C8 | −60.69 (12) | C14—C13—C18—C17 | 0.63 (14) |
C13—N4—C7—C8 | 117.41 (9) | N4—C13—C18—C17 | −176.47 (9) |
D—H···A | D—H | H···A | D···A | D—H···A |
C11—H11A···O1i | 0.95 | 2.59 | 3.3893 (12) | 141 |
Symmetry code: (i) x−1, y, z. |
Experimental details
Crystal data | |
Chemical formula | C18H22N4O |
Mr | 310.40 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 100 |
a, b, c (Å) | 7.9321 (3), 17.0477 (9), 12.2151 (6) |
β (°) | 98.583 (2) |
V (Å3) | 1633.28 (13) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.08 |
Crystal size (mm) | 0.25 × 0.20 × 0.15 |
Data collection | |
Diffractometer | Bruker Kappa APEXII Duo diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 51490, 4990, 4200 |
Rint | 0.029 |
(sin θ/λ)max (Å−1) | 0.715 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.039, 0.105, 1.04 |
No. of reflections | 4990 |
No. of parameters | 212 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.37, −0.23 |
Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg & Putz, 2005).
D—H···A | D—H | H···A | D···A | D—H···A |
C11—H11A···O1i | 0.95 | 2.59 | 3.3893 (12) | 141 |
Symmetry code: (i) x−1, y, z. |
Acknowledgements
The author thanks Dr W. Frey (Institut für Organische Chemie, Universität Stuttgart) for the data collection.
References
Brandenburg, K. & Putz, H. (2005). DIAMOND. Crystal Impact GbR, D-53002 Bonn, Germany. Google Scholar
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3-[bis(dimethylamino)methylene]-1,1-diphenylurea - also known as N-diphenylcarbamoyl-N',N',N'',N''- tetramethylguanidine - is a guanidine derivative bearing an additional urea moiety. Similar to 3-[bis(dimethylamino)methylene]-1,1-dimethylurea (N-dimethylcarbamoyl- N',N',N'',N''-tetramethylguanidine; Möllers et al., 2003), it can be used as a ligand in coordination chemistry to coordinate transition metals through one imino nitrogen and one carbonyl oxygen atom. Therefore, it proved to be important to determine the hitherto unknown crystal structure of the free ligand, to enable comparative investigations. According to the structure analysis, the C1–N3 bond in the title compound is 1.3179 (11) Å, indicating double bond character. The bond lengths C1–N2 = 1.3551 (11) Å and C1–N1 = 1.3737 (11) Å are elongated and characteristic for Cimine–Namine single bonds. The N–C1–N angles are: 115.91 (8)° (N1–C1–N2), 118.20 (8)° (N2–C1–N3) and 125.69 (8)° (N1–C1–N3), showing a deviation of the CN3 plane from an ideal trigonal-planar geometry. Bonds between N atoms and terminal C-methyl groups all have values close to typical single bonds (1.4529 (12)–1.4624 (12) Å). The C–O bond length in the diphenylcarbamoyl group is C6–O1 = 1.2305 (11) Å, and shows the expected double-bond character. The N–C bond lengths in the carbamoyl moiety are: N3–C6 = 1.3722 (11) Å, N4–C6 = 1.4028 (11) Å, N4–C13 = 1.4266 (11) Å and N4–C7 = 1.4367 (11) Å. They agree very well with X-ray structural data of the compounds 2- and 5-azido-N- (diphenylcarbamoyl)proline methyl ester (Lynch et al., 1995). The dihedral angle C1–N3–C6–N4 is -161.69 (8)° and the angle between the planes N1/C1/N2 and O1/C6/N4 is 51.68 (8)°, which shows a significant twisting of the diphenylcarbamoyl group relative to the CN3 plane (Fig. 1). Weak C–H···O hydrogen bonds between aromatic hydrogen atoms and carbonyl oxygen atoms of neighboring molecules have been determined [d(H···O) = 2.59 Å] (Tab. 1), generating a chain along the ab-plane (Fig. 2). On the other hand, intermolecular C–H···N hydrogen bonds play no prominent role in the stabilization of the crystal structure.