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The title compound, C
5H
7NO, was synthesized by the reaction of 1,3-cyclopentanedione with ammonium acetate under microwave conditions in 81% yield. The crystal packing is determined by intermolecular N—H
O and C—H
O hydrogen bonds.
Supporting information
CCDC reference: 636183
Key indicators
- Single-crystal X-ray study
- T = 103 K
- Mean (C-C) = 0.002 Å
- R factor = 0.054
- wR factor = 0.145
- Data-to-parameter ratio = 16.9
checkCIF/PLATON results
No syntax errors found
Alert level C
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical . ?
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given ....... ?
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor .... 2.20
0 ALERT level A = In general: serious problem
0 ALERT level B = Potentially serious problem
3 ALERT level C = Check and explain
0 ALERT level G = General alerts; check
1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
1 ALERT type 2 Indicator that the structure model may be wrong or deficient
0 ALERT type 3 Indicator that the structure quality may be low
1 ALERT type 4 Improvement, methodology, query or suggestion
0 ALERT type 5 Informative message, check
Data collection: SMART (Bruker, 2001); cell refinement: SMART; data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2000); software used to prepare material for publication: SHELXTL.
3-Amino-2-cyclopent-2-en-1-one
top
Crystal data top
C5H7NO | F(000) = 208 |
Mr = 97.12 | Dx = 1.314 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 5.6444 (17) Å | Cell parameters from 3168 reflections |
b = 12.085 (4) Å | θ = 2.8–27.1° |
c = 7.356 (2) Å | µ = 0.09 mm−1 |
β = 102.026 (4)° | T = 103 K |
V = 490.8 (3) Å3 | Chunk, colorless |
Z = 4 | 0.44 × 0.42 × 0.35 mm |
Data collection top
Bruker APEX-2 CCD area-detector diffractometer | 1084 independent reflections |
Radiation source: fine-focus sealed tube | 998 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.036 |
φ and ω scans | θmax = 27.1°, θmin = 3.3° |
Absorption correction: multi-scan (SADABS; Bruker, 2000) | h = −7→7 |
Tmin = 0.960, Tmax = 0.968 | k = −15→15 |
4315 measured reflections | l = −8→9 |
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)] = 0.054 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.145 | H-atom parameters constrained |
S = 1.10 | w = 1/[σ2(Fo2) + (0.0876P)2 + 0.1689P] where P = (Fo2 + 2Fc2)/3 |
1084 reflections | (Δ/σ)max < 0.001 |
64 parameters | Δρmax = 0.37 e Å−3 |
0 restraints | Δρmin = −0.27 e Å−3 |
Special details top
Experimental. 1H NMR (400 MHz, DMSO-d6): δ 7.21 (br, 2H), 4.774 (s, 1H),
2.445–2.420 (m, 2H), 2.140–2.08 (m, 2H); 13C NMR (100 MHz,
DMSO-d6): δ 202.318 (C), 178.437 (C), 99.085 (CH), 33.819 (CH2), 27.444
(CH2). MS m/z 97 (M +) 68, 55, 41. IR (CHCl3,
cm-1): 3687, 1622, and 1582. |
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 | 0.32396 (17) | 0.58198 (8) | 0.15752 (15) | 0.0302 (3) | |
C1 | 0.5074 (2) | 0.63130 (11) | 0.24429 (18) | 0.0222 (4) | |
C2 | 0.5427 (2) | 0.74659 (10) | 0.26634 (19) | 0.0230 (4) | |
H2A | 0.4265 | 0.8013 | 0.2164 | 0.028* | |
C3 | 0.7698 (2) | 0.76800 (11) | 0.37067 (19) | 0.0211 (4) | |
N3 | 0.8698 (2) | 0.86561 (9) | 0.41992 (16) | 0.0251 (3) | |
H3A | 0.7881 | 0.9267 | 0.3850 | 0.030* | |
H3B | 1.0178 | 0.8693 | 0.4875 | 0.030* | |
C4 | 0.9104 (2) | 0.66306 (10) | 0.42613 (19) | 0.0230 (3) | |
H4A | 0.9609 | 0.6573 | 0.5630 | 0.028* | |
H4B | 1.0561 | 0.6599 | 0.3712 | 0.028* | |
C5 | 0.7315 (2) | 0.57105 (10) | 0.3481 (2) | 0.0240 (4) | |
H5A | 0.7992 | 0.5227 | 0.2630 | 0.029* | |
H5B | 0.6927 | 0.5253 | 0.4497 | 0.029* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
O1 | 0.0225 (5) | 0.0179 (5) | 0.0458 (7) | −0.0013 (4) | −0.0033 (4) | −0.0028 (4) |
C1 | 0.0190 (6) | 0.0178 (7) | 0.0286 (7) | 0.0008 (4) | 0.0020 (5) | 0.0000 (4) |
C2 | 0.0220 (7) | 0.0146 (6) | 0.0301 (7) | 0.0032 (4) | −0.0001 (5) | 0.0006 (4) |
C3 | 0.0220 (7) | 0.0160 (6) | 0.0249 (7) | 0.0011 (4) | 0.0036 (5) | 0.0009 (4) |
N3 | 0.0229 (6) | 0.0159 (6) | 0.0329 (7) | −0.0006 (4) | −0.0024 (4) | −0.0004 (4) |
C4 | 0.0186 (6) | 0.0179 (6) | 0.0308 (7) | 0.0022 (4) | 0.0009 (5) | 0.0011 (5) |
C5 | 0.0213 (7) | 0.0155 (7) | 0.0340 (8) | 0.0019 (5) | 0.0027 (5) | 0.0029 (5) |
Geometric parameters (Å, º) top
O1—C1 | 1.2487 (16) | N3—H3A | 0.8800 |
C1—C2 | 1.4121 (18) | N3—H3B | 0.8800 |
C1—C5 | 1.5204 (17) | C4—C5 | 1.5310 (18) |
C2—C3 | 1.3745 (19) | C4—H4A | 0.9900 |
C2—H2A | 0.9500 | C4—H4B | 0.9900 |
C3—N3 | 1.3253 (17) | C5—H5A | 0.9900 |
C3—C4 | 1.5066 (17) | C5—H5B | 0.9900 |
| | | |
O1—C1—C2 | 127.72 (12) | C3—C4—C5 | 103.94 (10) |
O1—C1—C5 | 122.87 (12) | C3—C4—H4A | 111.0 |
C2—C1—C5 | 109.40 (11) | C5—C4—H4A | 111.0 |
C3—C2—C1 | 110.04 (11) | C3—C4—H4B | 111.0 |
C3—C2—H2A | 125.0 | C5—C4—H4B | 111.0 |
C1—C2—H2A | 125.0 | H4A—C4—H4B | 109.0 |
N3—C3—C2 | 127.93 (12) | C1—C5—C4 | 104.78 (10) |
N3—C3—C4 | 120.33 (12) | C1—C5—H5A | 110.8 |
C2—C3—C4 | 111.73 (11) | C4—C5—H5A | 110.8 |
C3—N3—H3A | 120.0 | C1—C5—H5B | 110.8 |
C3—N3—H3B | 120.0 | C4—C5—H5B | 110.8 |
H3A—N3—H3B | 120.0 | H5A—C5—H5B | 108.9 |
| | | |
O1—C1—C2—C3 | −179.67 (13) | C2—C3—C4—C5 | −2.65 (15) |
C5—C1—C2—C3 | 1.41 (16) | O1—C1—C5—C4 | 178.04 (12) |
C1—C2—C3—N3 | 179.52 (12) | C2—C1—C5—C4 | −2.97 (14) |
C1—C2—C3—C4 | 0.83 (17) | C3—C4—C5—C1 | 3.24 (14) |
N3—C3—C4—C5 | 178.56 (12) | | |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3A···O1i | 0.88 | 1.98 | 2.8458 (16) | 166 |
N3—H3B···O1ii | 0.88 | 2.00 | 2.8567 (16) | 165 |
C4—H4B···O1iii | 0.99 | 2.58 | 3.4979 (19) | 155 |
Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) x+1, −y+3/2, z+1/2; (iii) x+1, y, z. |
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