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In the molecule of the title compound, C
18H
18N
2O
2, the C7/C8/C9/O1/C10/C11 plane forms an angle of 92.5 (4)° with the phenyl plane. The most striking feature of the title compound is the formation of a three-dimensional network through N—H
N and N—H
O hydrogen bonds.
Supporting information
CCDC reference: 162829
Key indicators
- Single-crystal X-ray study
- T = 296 K
- Mean (C-C) = 0.002 Å
- R factor = 0.038
- wR factor = 0.102
- Data-to-parameter ratio = 13.4
checkCIF results
No syntax errors found
ADDSYM reports no extra symmetry
Alert Level C:
PLAT_371 Alert C Long C(sp2)-C(sp1) Bond C(8) - C(16) = 1.41 Ang.
0 Alert Level A = Potentially serious problem
0 Alert Level B = Potential problem
1 Alert Level C = Please check
The title compound was prepared by the reaction of 2-cyanocinnamonitrile with
5,5'-dimethyl-1,3-cyclohexanedione in ethylene under reflux for 4 h. The
colorless solid was purified by recrystallization from ethanol to obtain
single crystals suitable for X-ray diffraction. The product was characterized
by NMR, IR and elemental analyses, giving results consistent with those in the
literature (Singh et al., 1996).
The H atoms of the amino group were located in difference Fourier syntheses. The
other H atoms were located by geometry and included in the structure-factor
calculations.
Structure description
top
Polyfunctionalized benzo-4H-pyrans are structural units of a number of
natural products (Hatakeyama et al., 1988) and, because of their
inherent reactivity, the pyran rings are versatile synthons (Singh et
al., 1996). On the other hand, substituted benzo-4H-pyrans possess
varied biological activity (Hassanien et al., 1999). Since the
stereochemistry is so important in the rational design of new functional
molecules, we report herein the crystal structure of the title compound, (I).
In the structure (Fig. 1) of the neutral molecule (I), the C7/C8/C9/O1/C10/C11
plane forms an angle of 92.5 (4)° with the phenyl plane. The nitrile group is
typical [N≡C 1.1448 (19) Å].
A notable feature of (I) is the formation of a three-dimensional network
through hydrogen bonds, as shown in Fig. 2. These are in the normal range of
weak interactions (Sasada, 1984). The amino N2 atom of one molecule links
through H2B to the nitrile N1 atom of another molecule, creating a dimer. The
amino N2 atom of one molecule also links through H2A to the keto O2 atom of
another molecule to form the three-dimensional framework.
Data collection: SMART (Bruker, 1998); cell refinement: SMART; data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976).
2-Amino-7,7-dimethyl-4-benzyl-5-oxo-4,5,6,8-tetrahydro-7
H-chromene
-3-carbornitrile
top
Crystal data top
C18H18N2O2 | F(000) = 624 |
Mr = 294.34 | Dx = 1.240 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 11.307 (1) Å | Cell parameters from 25 reflections |
b = 9.475 (1) Å | θ = 3.3–15.1° |
c = 14.919 (2) Å | µ = 0.08 mm−1 |
β = 99.34 (1)° | T = 296 K |
V = 1577.1 (3) Å3 | Prism, colorless |
Z = 4 | 0.56 × 0.50 × 0.40 mm |
Data collection top
Bruker SMART 1000 diffractometer | 1942 reflections with I > 2σ(I) |
Radiation source: normal-focus sealed tube | Rint = 0.013 |
Graphite monochromator | θmax = 25.0°, θmin = 1.8° |
ω scans | h = 0→13 |
3252 measured reflections | k = 0→11 |
2783 independent reflections | l = −17→17 |
Refinement top
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)] = 0.038 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.102 | w = 1/[σ2(Fo2) + (0.0561P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.02 | (Δ/σ)max = 0.001 |
2783 reflections | Δρmax = 0.19 e Å−3 |
208 parameters | Δρmin = −0.14 e Å−3 |
0 restraints | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.044 (3) |
Crystal data top
C18H18N2O2 | V = 1577.1 (3) Å3 |
Mr = 294.34 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 11.307 (1) Å | µ = 0.08 mm−1 |
b = 9.475 (1) Å | T = 296 K |
c = 14.919 (2) Å | 0.56 × 0.50 × 0.40 mm |
β = 99.34 (1)° | |
Data collection top
Bruker SMART 1000 diffractometer | 1942 reflections with I > 2σ(I) |
3252 measured reflections | Rint = 0.013 |
2783 independent reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.038 | 0 restraints |
wR(F2) = 0.102 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.02 | Δρmax = 0.19 e Å−3 |
2783 reflections | Δρmin = −0.14 e Å−3 |
208 parameters | |
Special details top
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 | 0.38594 (9) | 0.19829 (12) | 0.53586 (7) | 0.0478 (3) | |
O2 | 0.39678 (10) | 0.42950 (13) | 0.81702 (8) | 0.0578 (4) | |
N1 | −0.00294 (13) | 0.07976 (16) | 0.59525 (10) | 0.0590 (4) | |
N2 | 0.24217 (15) | 0.06252 (18) | 0.46297 (11) | 0.0604 (5) | |
C1 | 0.09420 (14) | 0.48169 (19) | 0.69650 (12) | 0.0554 (5) | |
H1 | 0.0781 | 0.4273 | 0.7450 | 0.067* | |
C2 | 0.03121 (17) | 0.6051 (2) | 0.67480 (15) | 0.0680 (6) | |
H2 | −0.0275 | 0.6321 | 0.7084 | 0.082* | |
C3 | 0.05366 (18) | 0.6873 (2) | 0.60535 (13) | 0.0681 (6) | |
H3 | 0.0103 | 0.7699 | 0.5908 | 0.082* | |
C4 | 0.1409 (2) | 0.6476 (2) | 0.55686 (15) | 0.0919 (8) | |
H4 | 0.1587 | 0.7043 | 0.5100 | 0.110* | |
C5 | 0.2025 (2) | 0.5232 (2) | 0.57764 (13) | 0.0809 (7) | |
H5 | 0.2606 | 0.4962 | 0.5435 | 0.097* | |
C6 | 0.18021 (13) | 0.43816 (17) | 0.64756 (10) | 0.0411 (4) | |
C7 | 0.24657 (13) | 0.29886 (15) | 0.66897 (10) | 0.0385 (4) | |
H7 | 0.2291 | 0.2648 | 0.7275 | 0.046* | |
C8 | 0.20547 (13) | 0.18659 (16) | 0.59795 (10) | 0.0397 (4) | |
C9 | 0.27108 (13) | 0.14927 (17) | 0.53365 (10) | 0.0425 (4) | |
C10 | 0.44066 (13) | 0.26733 (15) | 0.61272 (10) | 0.0386 (4) | |
C11 | 0.38057 (13) | 0.31358 (15) | 0.67676 (10) | 0.0371 (4) | |
C12 | 0.44793 (15) | 0.38037 (16) | 0.75796 (10) | 0.0434 (4) | |
C13 | 0.58247 (14) | 0.3810 (2) | 0.76731 (11) | 0.0563 (5) | |
H13A | 0.6132 | 0.2940 | 0.7965 | 0.068* | |
H13B | 0.6136 | 0.4585 | 0.8067 | 0.068* | |
C14 | 0.62930 (14) | 0.39550 (18) | 0.67704 (11) | 0.0473 (4) | |
C15 | 0.57150 (13) | 0.28023 (17) | 0.61307 (11) | 0.0465 (4) | |
H15A | 0.5853 | 0.3008 | 0.5519 | 0.056* | |
H15B | 0.6096 | 0.1907 | 0.6312 | 0.056* | |
C16 | 0.09006 (14) | 0.12739 (17) | 0.59504 (10) | 0.0428 (4) | |
C17 | 0.59603 (18) | 0.5406 (2) | 0.63562 (14) | 0.0682 (6) | |
H17A | 0.5105 | 0.5515 | 0.6259 | 0.102* | |
H17B | 0.6246 | 0.5487 | 0.5787 | 0.102* | |
H17C | 0.6321 | 0.6128 | 0.6763 | 0.102* | |
C18 | 0.76479 (16) | 0.3782 (3) | 0.69277 (15) | 0.0805 (7) | |
H18A | 0.7855 | 0.2872 | 0.7189 | 0.121* | |
H18B | 0.8007 | 0.4504 | 0.7334 | 0.121* | |
H18C | 0.7936 | 0.3860 | 0.6359 | 0.121* | |
H2A | 0.2899 (17) | 0.056 (2) | 0.4222 (13) | 0.068 (6)* | |
H2B | 0.1700 (16) | 0.0265 (18) | 0.4520 (11) | 0.054 (5)* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
O1 | 0.0410 (6) | 0.0565 (7) | 0.0487 (6) | −0.0109 (5) | 0.0161 (5) | −0.0157 (6) |
O2 | 0.0618 (8) | 0.0685 (8) | 0.0462 (7) | −0.0064 (6) | 0.0177 (6) | −0.0128 (6) |
N1 | 0.0507 (9) | 0.0708 (11) | 0.0583 (9) | −0.0157 (8) | 0.0175 (7) | −0.0097 (8) |
N2 | 0.0487 (10) | 0.0773 (12) | 0.0588 (10) | −0.0214 (9) | 0.0198 (8) | −0.0297 (9) |
C1 | 0.0545 (11) | 0.0535 (11) | 0.0642 (11) | 0.0079 (9) | 0.0271 (9) | 0.0057 (9) |
C2 | 0.0611 (12) | 0.0657 (13) | 0.0834 (14) | 0.0199 (10) | 0.0302 (11) | 0.0015 (11) |
C3 | 0.0761 (14) | 0.0589 (12) | 0.0682 (13) | 0.0283 (11) | 0.0089 (11) | 0.0016 (10) |
C4 | 0.130 (2) | 0.0824 (16) | 0.0735 (15) | 0.0496 (15) | 0.0457 (14) | 0.0345 (13) |
C5 | 0.1047 (17) | 0.0796 (15) | 0.0706 (14) | 0.0456 (13) | 0.0508 (13) | 0.0277 (12) |
C6 | 0.0407 (9) | 0.0445 (9) | 0.0386 (8) | 0.0023 (7) | 0.0079 (7) | −0.0027 (7) |
C7 | 0.0398 (8) | 0.0409 (9) | 0.0366 (8) | 0.0006 (7) | 0.0120 (6) | 0.0015 (7) |
C8 | 0.0358 (8) | 0.0403 (8) | 0.0442 (9) | −0.0028 (7) | 0.0104 (7) | −0.0014 (7) |
C9 | 0.0407 (9) | 0.0420 (9) | 0.0457 (9) | −0.0049 (7) | 0.0099 (7) | −0.0019 (8) |
C10 | 0.0396 (8) | 0.0340 (8) | 0.0424 (9) | −0.0020 (7) | 0.0072 (7) | −0.0020 (7) |
C11 | 0.0382 (8) | 0.0351 (8) | 0.0385 (9) | 0.0007 (7) | 0.0081 (7) | 0.0000 (7) |
C12 | 0.0496 (10) | 0.0427 (9) | 0.0388 (9) | −0.0028 (8) | 0.0103 (7) | 0.0007 (7) |
C13 | 0.0488 (10) | 0.0706 (12) | 0.0486 (10) | −0.0096 (9) | 0.0052 (8) | −0.0046 (9) |
C14 | 0.0399 (9) | 0.0521 (10) | 0.0502 (10) | −0.0083 (8) | 0.0086 (7) | −0.0060 (8) |
C15 | 0.0393 (9) | 0.0456 (10) | 0.0563 (10) | 0.0002 (7) | 0.0129 (8) | −0.0036 (8) |
C16 | 0.0449 (10) | 0.0452 (9) | 0.0396 (9) | −0.0012 (8) | 0.0102 (7) | −0.0025 (7) |
C17 | 0.0838 (15) | 0.0507 (11) | 0.0750 (13) | −0.0181 (10) | 0.0276 (11) | −0.0065 (10) |
C18 | 0.0438 (11) | 0.1192 (19) | 0.0783 (14) | −0.0144 (12) | 0.0095 (10) | −0.0203 (14) |
Geometric parameters (Å, º) top
O1—C9 | 1.3746 (17) | C7—C11 | 1.5071 (19) |
O1—C10 | 1.3767 (17) | C7—C8 | 1.520 (2) |
O2—C12 | 1.2219 (18) | C8—C9 | 1.351 (2) |
N1—C16 | 1.1448 (19) | C8—C16 | 1.415 (2) |
N2—C9 | 1.335 (2) | C10—C11 | 1.333 (2) |
C1—C6 | 1.371 (2) | C10—C15 | 1.4835 (19) |
C1—C2 | 1.380 (2) | C11—C12 | 1.466 (2) |
C2—C3 | 1.353 (3) | C12—C13 | 1.505 (2) |
C3—C4 | 1.368 (3) | C13—C14 | 1.531 (2) |
C4—C5 | 1.378 (3) | C14—C18 | 1.521 (2) |
C5—C6 | 1.373 (2) | C14—C15 | 1.526 (2) |
C6—C7 | 1.526 (2) | C14—C17 | 1.529 (2) |
| | | |
C9—O1—C10 | 118.41 (11) | C11—C10—O1 | 122.73 (13) |
C6—C1—C2 | 120.91 (17) | C11—C10—C15 | 126.46 (14) |
C3—C2—C1 | 120.92 (18) | O1—C10—C15 | 110.81 (12) |
C2—C3—C4 | 119.17 (18) | C10—C11—C12 | 118.51 (14) |
C3—C4—C5 | 119.9 (2) | C10—C11—C7 | 122.50 (14) |
C6—C5—C4 | 121.61 (18) | C12—C11—C7 | 118.99 (13) |
C1—C6—C5 | 117.49 (16) | O2—C12—C11 | 121.14 (15) |
C1—C6—C7 | 121.05 (14) | O2—C12—C13 | 121.42 (15) |
C5—C6—C7 | 121.45 (14) | C11—C12—C13 | 117.40 (14) |
C11—C7—C8 | 107.96 (12) | C12—C13—C14 | 114.05 (14) |
C11—C7—C6 | 112.96 (12) | C18—C14—C15 | 109.75 (14) |
C8—C7—C6 | 112.03 (12) | C18—C14—C17 | 109.57 (16) |
C9—C8—C16 | 118.97 (14) | C15—C14—C17 | 109.79 (14) |
C9—C8—C7 | 122.48 (13) | C18—C14—C13 | 109.76 (15) |
C16—C8—C7 | 118.36 (13) | C15—C14—C13 | 108.16 (13) |
N2—C9—C8 | 129.01 (15) | C17—C14—C13 | 109.79 (15) |
N2—C9—O1 | 109.64 (14) | C10—C15—C14 | 112.76 (13) |
C8—C9—O1 | 121.32 (14) | N1—C16—C8 | 178.11 (17) |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2B···N1i | 0.875 (17) | 2.156 (18) | 3.021 (2) | 169.8 (15) |
N2—H2A···O2ii | 0.88 (2) | 2.13 (2) | 3.006 (2) | 171.6 (18) |
Symmetry codes: (i) −x, −y, −z+1; (ii) x, −y+1/2, z−1/2. |
Experimental details
Crystal data |
Chemical formula | C18H18N2O2 |
Mr | 294.34 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 296 |
a, b, c (Å) | 11.307 (1), 9.475 (1), 14.919 (2) |
β (°) | 99.34 (1) |
V (Å3) | 1577.1 (3) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.08 |
Crystal size (mm) | 0.56 × 0.50 × 0.40 |
|
Data collection |
Diffractometer | Bruker SMART 1000 |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 3252, 2783, 1942 |
Rint | 0.013 |
(sin θ/λ)max (Å−1) | 0.595 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.038, 0.102, 1.02 |
No. of reflections | 2783 |
No. of parameters | 208 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.19, −0.14 |
Selected geometric parameters (Å, º) topO1—C9 | 1.3746 (17) | N2—C9 | 1.335 (2) |
O1—C10 | 1.3767 (17) | C8—C9 | 1.351 (2) |
O2—C12 | 1.2219 (18) | C10—C11 | 1.333 (2) |
N1—C16 | 1.1448 (19) | | |
| | | |
C9—O1—C10 | 118.41 (11) | O2—C12—C11 | 121.14 (15) |
N2—C9—C8 | 129.01 (15) | O2—C12—C13 | 121.42 (15) |
N2—C9—O1 | 109.64 (14) | N1—C16—C8 | 178.11 (17) |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2B···N1i | 0.875 (17) | 2.156 (18) | 3.021 (2) | 169.8 (15) |
N2—H2A···O2ii | 0.88 (2) | 2.13 (2) | 3.006 (2) | 171.6 (18) |
Symmetry codes: (i) −x, −y, −z+1; (ii) x, −y+1/2, z−1/2. |
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Polyfunctionalized benzo-4H-pyrans are structural units of a number of natural products (Hatakeyama et al., 1988) and, because of their inherent reactivity, the pyran rings are versatile synthons (Singh et al., 1996). On the other hand, substituted benzo-4H-pyrans possess varied biological activity (Hassanien et al., 1999). Since the stereochemistry is so important in the rational design of new functional molecules, we report herein the crystal structure of the title compound, (I).
In the structure (Fig. 1) of the neutral molecule (I), the C7/C8/C9/O1/C10/C11 plane forms an angle of 92.5 (4)° with the phenyl plane. The nitrile group is typical [N≡C 1.1448 (19) Å].
A notable feature of (I) is the formation of a three-dimensional network through hydrogen bonds, as shown in Fig. 2. These are in the normal range of weak interactions (Sasada, 1984). The amino N2 atom of one molecule links through H2B to the nitrile N1 atom of another molecule, creating a dimer. The amino N2 atom of one molecule also links through H2A to the keto O2 atom of another molecule to form the three-dimensional framework.