organic compounds
(Z)-Ethyl 3-(2,6-diisopropylanilino)but-2-enoate
aInstituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, México 04510, Mexico
*Correspondence e-mail: simonho@unam.mx, majo00@yahoo.com
The title compound, C18H27NO2, crystallizes as the enamine form with Z geometry. The β-enaminoester fragment forms a dihedral angle of 87.5 (1)° with the isopropylphenyl frame. The structure exhibits an intramolecular N—H⋯O hydrogen bond. In addition, in the crystal, molecules are linked by a centrosymmetric intermolecular N—H⋯O hydrogen bond.
Related literature
For methods used in the preparation of β-enaminoketones and β-enaminoesters, see: Zhang & Yang (2009); Bartoli et al. (2004); Braibante et al. (2006). These compounds are used the preparation of key intermediates of pharmaceutical products (Michael et al., 1999), aminoacids (Palmieri & Cimmerelli, 1996), and (David et al., 1999). For our work on the synthesis of enaminoesters, see: Amézquita-Valencia et al. (2009).
Experimental
Crystal data
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Data collection
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Refinement
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Data collection: SMART (Bruker, 1999); cell SAINT (Bruker, 1999); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.
Supporting information
10.1107/S1600536810003260/gw2075sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536810003260/gw2075Isup2.hkl
Compound (I) was obtained following the procedure described in Amézquita-Valencia, et al. 2009. The product recrystallized from methanol. Yield: 92%, M.p. 326.3°
H atom on amine group was found in Fourier map and refined with Uiso(H) = 1.2 UeqC(sp2). H on C atoms were placed in geometrically idealized positions [0.93 Å(CH) 0.96 Å(CH arom) and 0.97 Å (CH3)] tied to the parent atom with Uiso(H) = 1.2 UeqC(sp2) and 1.5 UeqC(sp3) and refined using the riding model.
Data collection: SMART (Bruker, 1999); cell
SAINT (Bruker, 1999); data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).C18H27NO2 | Z = 2 |
Mr = 289.41 | F(000) = 316 |
Triclinic, P1 | Dx = 1.092 Mg m−3 |
Hall symbol: -P 1 | Melting point: 326.3(2) K |
a = 8.4750 (17) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 8.8995 (18) Å | Cell parameters from 1942 reflections |
c = 11.956 (2) Å | θ = 2.5–24.1° |
α = 94.901 (3)° | µ = 0.07 mm−1 |
β = 91.801 (3)° | T = 298 K |
γ = 101.255 (4)° | Prism, colorless |
V = 880.1 (3) Å3 | 0.29 × 0.21 × 0.05 mm |
Bruker SMART APEX CCD area-detector diffractometer | 1574 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.052 |
Graphite monochromator | θmax = 25.4°, θmin = 1.7° |
Detector resolution: 0.83 pixels mm-1 | h = −10→10 |
ω scans | k = −10→10 |
7319 measured reflections | l = −14→14 |
3233 independent reflections |
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)] = 0.041 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.085 | H atoms treated by a mixture of independent and constrained refinement |
S = 0.84 | w = 1/[σ2(Fo2) + (0.020P)2] where P = (Fo2 + 2Fc2)/3 |
3233 reflections | (Δ/σ)max < 0.001 |
199 parameters | Δρmax = 0.11 e Å−3 |
1 restraint | Δρmin = −0.10 e Å−3 |
C18H27NO2 | γ = 101.255 (4)° |
Mr = 289.41 | V = 880.1 (3) Å3 |
Triclinic, P1 | Z = 2 |
a = 8.4750 (17) Å | Mo Kα radiation |
b = 8.8995 (18) Å | µ = 0.07 mm−1 |
c = 11.956 (2) Å | T = 298 K |
α = 94.901 (3)° | 0.29 × 0.21 × 0.05 mm |
β = 91.801 (3)° |
Bruker SMART APEX CCD area-detector diffractometer | 1574 reflections with I > 2σ(I) |
7319 measured reflections | Rint = 0.052 |
3233 independent reflections |
R[F2 > 2σ(F2)] = 0.041 | 1 restraint |
wR(F2) = 0.085 | H atoms treated by a mixture of independent and constrained refinement |
S = 0.84 | Δρmax = 0.11 e Å−3 |
3233 reflections | Δρmin = −0.10 e Å−3 |
199 parameters |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 | ||
O1 | 0.40766 (16) | 0.15127 (14) | 0.48653 (10) | 0.0730 (4) | |
O2 | 0.30098 (15) | 0.36079 (13) | 0.46776 (9) | 0.0683 (4) | |
N1 | 0.49463 (18) | 0.01679 (16) | 0.28928 (11) | 0.0554 (4) | |
H1 | 0.4882 (18) | 0.0192 (18) | 0.3638 (8) | 0.066* | |
C1 | 0.3661 (2) | 0.2415 (2) | 0.42624 (15) | 0.0556 (5) | |
C2 | 0.3774 (2) | 0.23743 (19) | 0.30792 (14) | 0.0574 (5) | |
H2 | 0.3404 | 0.3129 | 0.2713 | 0.069* | |
C3 | 0.4383 (2) | 0.1311 (2) | 0.24509 (14) | 0.0521 (5) | |
C4 | 0.4449 (2) | 0.1348 (2) | 0.12035 (14) | 0.0821 (7) | |
H4A | 0.5552 | 0.1526 | 0.0999 | 0.123* | |
H4B | 0.3952 | 0.2161 | 0.0974 | 0.123* | |
H4C | 0.3885 | 0.0382 | 0.0838 | 0.123* | |
C5 | 0.5595 (2) | −0.1002 (2) | 0.22757 (13) | 0.0508 (5) | |
C6 | 0.7234 (2) | −0.0729 (2) | 0.20876 (14) | 0.0579 (5) | |
C7 | 0.7848 (2) | −0.1914 (3) | 0.15333 (15) | 0.0697 (6) | |
H7 | 0.8937 | −0.1763 | 0.1392 | 0.084* | |
C8 | 0.6859 (3) | −0.3301 (3) | 0.11939 (15) | 0.0710 (6) | |
H8 | 0.7291 | −0.4091 | 0.0842 | 0.085* | |
C9 | 0.5242 (3) | −0.3537 (2) | 0.13675 (14) | 0.0638 (5) | |
H9 | 0.4591 | −0.4480 | 0.1118 | 0.077* | |
C10 | 0.4557 (2) | −0.2397 (2) | 0.19079 (13) | 0.0529 (5) | |
C11 | 0.8341 (2) | 0.0779 (2) | 0.24878 (18) | 0.0793 (6) | |
H11 | 0.7657 | 0.1534 | 0.2650 | 0.095* | |
C12 | 0.9507 (3) | 0.1411 (3) | 0.1612 (2) | 0.1274 (9) | |
H12A | 1.0269 | 0.0753 | 0.1486 | 0.191* | |
H12B | 1.0068 | 0.2428 | 0.1879 | 0.191* | |
H12C | 0.8915 | 0.1448 | 0.0920 | 0.191* | |
C13 | 0.9264 (3) | 0.0662 (3) | 0.35821 (18) | 0.1140 (8) | |
H13A | 0.8516 | 0.0412 | 0.4157 | 0.171* | |
H13B | 0.9972 | 0.1628 | 0.3807 | 0.171* | |
H13C | 0.9884 | −0.0129 | 0.3471 | 0.171* | |
C14 | 0.2780 (2) | −0.2639 (2) | 0.21149 (15) | 0.0665 (5) | |
H14 | 0.2455 | −0.1650 | 0.2053 | 0.080* | |
C15 | 0.2454 (2) | −0.3071 (2) | 0.33083 (17) | 0.0971 (7) | |
H15A | 0.2766 | −0.4035 | 0.3403 | 0.146* | |
H15B | 0.1326 | −0.3164 | 0.3431 | 0.146* | |
H15C | 0.3064 | −0.2286 | 0.3840 | 0.146* | |
C16 | 0.1727 (2) | −0.3808 (2) | 0.12593 (19) | 0.1022 (8) | |
H16A | 0.1915 | −0.3503 | 0.0516 | 0.153* | |
H16B | 0.0614 | −0.3855 | 0.1412 | 0.153* | |
H16C | 0.1988 | −0.4803 | 0.1311 | 0.153* | |
C17 | 0.2874 (3) | 0.3794 (2) | 0.58714 (14) | 0.0862 (7) | |
H17A | 0.3930 | 0.3940 | 0.6249 | 0.103* | |
H17B | 0.2202 | 0.2884 | 0.6120 | 0.103* | |
C18 | 0.2146 (2) | 0.5158 (2) | 0.61480 (15) | 0.0817 (6) | |
H18A | 0.2811 | 0.6051 | 0.5891 | 0.123* | |
H18B | 0.2064 | 0.5312 | 0.6947 | 0.123* | |
H18C | 0.1092 | 0.4994 | 0.5785 | 0.123* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.1105 (11) | 0.0678 (9) | 0.0517 (8) | 0.0418 (8) | 0.0065 (7) | 0.0118 (7) |
O2 | 0.1025 (11) | 0.0614 (8) | 0.0497 (8) | 0.0382 (8) | 0.0095 (7) | 0.0023 (6) |
N1 | 0.0797 (11) | 0.0503 (9) | 0.0418 (8) | 0.0262 (8) | 0.0075 (8) | 0.0038 (8) |
C1 | 0.0659 (14) | 0.0490 (12) | 0.0539 (12) | 0.0173 (11) | 0.0035 (10) | 0.0014 (10) |
C2 | 0.0800 (14) | 0.0495 (11) | 0.0487 (11) | 0.0265 (10) | 0.0032 (10) | 0.0070 (9) |
C3 | 0.0637 (13) | 0.0487 (11) | 0.0461 (11) | 0.0158 (10) | 0.0014 (9) | 0.0067 (9) |
C4 | 0.1282 (19) | 0.0817 (15) | 0.0491 (11) | 0.0482 (14) | 0.0115 (11) | 0.0131 (11) |
C5 | 0.0670 (14) | 0.0497 (12) | 0.0405 (10) | 0.0222 (11) | 0.0045 (10) | 0.0052 (9) |
C6 | 0.0666 (15) | 0.0558 (13) | 0.0546 (11) | 0.0179 (12) | 0.0060 (10) | 0.0089 (10) |
C7 | 0.0696 (15) | 0.0803 (15) | 0.0657 (13) | 0.0283 (14) | 0.0127 (11) | 0.0091 (12) |
C8 | 0.0917 (18) | 0.0764 (16) | 0.0537 (12) | 0.0419 (14) | 0.0057 (12) | −0.0036 (11) |
C9 | 0.0837 (16) | 0.0548 (12) | 0.0541 (12) | 0.0210 (12) | −0.0033 (11) | −0.0027 (10) |
C10 | 0.0703 (15) | 0.0498 (12) | 0.0429 (10) | 0.0222 (11) | 0.0012 (10) | 0.0050 (9) |
C11 | 0.0711 (15) | 0.0695 (15) | 0.0960 (17) | 0.0116 (13) | 0.0051 (13) | 0.0055 (13) |
C12 | 0.112 (2) | 0.124 (2) | 0.139 (2) | −0.0138 (17) | 0.0189 (18) | 0.0496 (18) |
C13 | 0.117 (2) | 0.1073 (19) | 0.0989 (18) | −0.0166 (16) | −0.0228 (16) | 0.0004 (15) |
C14 | 0.0711 (15) | 0.0559 (13) | 0.0741 (14) | 0.0173 (11) | 0.0021 (11) | 0.0060 (11) |
C15 | 0.0893 (18) | 0.1064 (18) | 0.0986 (17) | 0.0148 (14) | 0.0304 (14) | 0.0286 (15) |
C16 | 0.0800 (17) | 0.0877 (17) | 0.132 (2) | 0.0130 (14) | −0.0184 (15) | −0.0127 (15) |
C17 | 0.137 (2) | 0.0852 (15) | 0.0495 (12) | 0.0540 (15) | 0.0167 (12) | 0.0017 (11) |
C18 | 0.1002 (17) | 0.0771 (15) | 0.0726 (14) | 0.0309 (13) | 0.0199 (12) | −0.0032 (11) |
O1—C1 | 1.2173 (18) | C11—C13 | 1.525 (3) |
O2—C1 | 1.3543 (18) | C11—C12 | 1.529 (2) |
O2—C17 | 1.4337 (18) | C11—H11 | 0.9800 |
N1—C3 | 1.3439 (19) | C12—H12A | 0.9600 |
N1—C5 | 1.4310 (19) | C12—H12B | 0.9600 |
N1—H1 | 0.894 (8) | C12—H12C | 0.9600 |
C1—C2 | 1.419 (2) | C13—H13A | 0.9600 |
C2—C3 | 1.350 (2) | C13—H13B | 0.9600 |
C2—H2 | 0.9300 | C13—H13C | 0.9600 |
C3—C4 | 1.497 (2) | C14—C16 | 1.525 (2) |
C4—H4A | 0.9600 | C14—C15 | 1.529 (2) |
C4—H4B | 0.9600 | C14—H14 | 0.9800 |
C4—H4C | 0.9600 | C15—H15A | 0.9600 |
C5—C6 | 1.392 (2) | C15—H15B | 0.9600 |
C5—C10 | 1.402 (2) | C15—H15C | 0.9600 |
C6—C7 | 1.392 (2) | C16—H16A | 0.9600 |
C6—C11 | 1.510 (2) | C16—H16B | 0.9600 |
C7—C8 | 1.371 (3) | C16—H16C | 0.9600 |
C7—H7 | 0.9300 | C17—C18 | 1.483 (2) |
C8—C9 | 1.370 (2) | C17—H17A | 0.9700 |
C8—H8 | 0.9300 | C17—H17B | 0.9700 |
C9—C10 | 1.388 (2) | C18—H18A | 0.9600 |
C9—H9 | 0.9300 | C18—H18B | 0.9600 |
C10—C14 | 1.510 (2) | C18—H18C | 0.9600 |
C1—O2—C17 | 116.95 (14) | C11—C12—H12A | 109.5 |
C3—N1—C5 | 125.68 (14) | C11—C12—H12B | 109.5 |
C3—N1—H1 | 113.3 (10) | H12A—C12—H12B | 109.5 |
C5—N1—H1 | 121.1 (10) | C11—C12—H12C | 109.5 |
O1—C1—O2 | 121.97 (16) | H12A—C12—H12C | 109.5 |
O1—C1—C2 | 126.24 (17) | H12B—C12—H12C | 109.5 |
O2—C1—C2 | 111.79 (16) | C11—C13—H13A | 109.5 |
C3—C2—C1 | 124.19 (16) | C11—C13—H13B | 109.5 |
C3—C2—H2 | 117.9 | H13A—C13—H13B | 109.5 |
C1—C2—H2 | 117.9 | C11—C13—H13C | 109.5 |
N1—C3—C2 | 122.83 (15) | H13A—C13—H13C | 109.5 |
N1—C3—C4 | 116.49 (15) | H13B—C13—H13C | 109.5 |
C2—C3—C4 | 120.68 (15) | C10—C14—C16 | 113.93 (16) |
C3—C4—H4A | 109.5 | C10—C14—C15 | 111.14 (15) |
C3—C4—H4B | 109.5 | C16—C14—C15 | 110.36 (17) |
H4A—C4—H4B | 109.5 | C10—C14—H14 | 107.0 |
C3—C4—H4C | 109.5 | C16—C14—H14 | 107.0 |
H4A—C4—H4C | 109.5 | C15—C14—H14 | 107.0 |
H4B—C4—H4C | 109.5 | C14—C15—H15A | 109.5 |
C6—C5—C10 | 122.50 (16) | C14—C15—H15B | 109.5 |
C6—C5—N1 | 118.98 (17) | H15A—C15—H15B | 109.5 |
C10—C5—N1 | 118.49 (17) | C14—C15—H15C | 109.5 |
C7—C6—C5 | 117.78 (18) | H15A—C15—H15C | 109.5 |
C7—C6—C11 | 120.22 (19) | H15B—C15—H15C | 109.5 |
C5—C6—C11 | 121.99 (17) | C14—C16—H16A | 109.5 |
C8—C7—C6 | 120.58 (19) | C14—C16—H16B | 109.5 |
C8—C7—H7 | 119.7 | H16A—C16—H16B | 109.5 |
C6—C7—H7 | 119.7 | C14—C16—H16C | 109.5 |
C9—C8—C7 | 120.76 (18) | H16A—C16—H16C | 109.5 |
C9—C8—H8 | 119.6 | H16B—C16—H16C | 109.5 |
C7—C8—H8 | 119.6 | O2—C17—C18 | 108.30 (15) |
C8—C9—C10 | 121.37 (19) | O2—C17—H17A | 110.0 |
C8—C9—H9 | 119.3 | C18—C17—H17A | 110.0 |
C10—C9—H9 | 119.3 | O2—C17—H17B | 110.0 |
C9—C10—C5 | 116.97 (17) | C18—C17—H17B | 110.0 |
C9—C10—C14 | 122.14 (18) | H17A—C17—H17B | 108.4 |
C5—C10—C14 | 120.88 (16) | C17—C18—H18A | 109.5 |
C6—C11—C13 | 111.31 (17) | C17—C18—H18B | 109.5 |
C6—C11—C12 | 113.78 (18) | H18A—C18—H18B | 109.5 |
C13—C11—C12 | 110.29 (19) | C17—C18—H18C | 109.5 |
C6—C11—H11 | 107.0 | H18A—C18—H18C | 109.5 |
C13—C11—H11 | 107.0 | H18B—C18—H18C | 109.5 |
C12—C11—H11 | 107.0 | ||
C17—O2—C1—O1 | 1.9 (2) | C7—C8—C9—C10 | −1.2 (3) |
C17—O2—C1—C2 | −178.36 (16) | C8—C9—C10—C5 | −0.6 (2) |
O1—C1—C2—C3 | −0.6 (3) | C8—C9—C10—C14 | −179.51 (16) |
O2—C1—C2—C3 | 179.68 (17) | C6—C5—C10—C9 | 1.9 (2) |
C5—N1—C3—C2 | 179.47 (17) | N1—C5—C10—C9 | −176.47 (13) |
C5—N1—C3—C4 | 0.0 (3) | C6—C5—C10—C14 | −179.16 (14) |
C1—C2—C3—N1 | 0.2 (3) | N1—C5—C10—C14 | 2.5 (2) |
C1—C2—C3—C4 | 179.67 (17) | C7—C6—C11—C13 | −79.3 (2) |
C3—N1—C5—C6 | 88.8 (2) | C5—C6—C11—C13 | 99.3 (2) |
C3—N1—C5—C10 | −92.8 (2) | C7—C6—C11—C12 | 46.0 (2) |
C10—C5—C6—C7 | −1.4 (2) | C5—C6—C11—C12 | −135.40 (19) |
N1—C5—C6—C7 | 176.92 (14) | C9—C10—C14—C16 | −27.7 (2) |
C10—C5—C6—C11 | 179.97 (15) | C5—C10—C14—C16 | 153.41 (16) |
N1—C5—C6—C11 | −1.7 (2) | C9—C10—C14—C15 | 97.75 (19) |
C5—C6—C7—C8 | −0.4 (2) | C5—C10—C14—C15 | −81.16 (19) |
C11—C6—C7—C8 | 178.25 (17) | C1—O2—C17—C18 | 179.70 (16) |
C6—C7—C8—C9 | 1.7 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O1 | 0.89 (1) | 2.02 (1) | 2.7402 (18) | 137 (1) |
N1—H1···O1i | 0.89 (1) | 2.68 (1) | 3.3371 (18) | 132 (1) |
Symmetry code: (i) −x+1, −y, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C18H27NO2 |
Mr | 289.41 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 298 |
a, b, c (Å) | 8.4750 (17), 8.8995 (18), 11.956 (2) |
α, β, γ (°) | 94.901 (3), 91.801 (3), 101.255 (4) |
V (Å3) | 880.1 (3) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.07 |
Crystal size (mm) | 0.29 × 0.21 × 0.05 |
Data collection | |
Diffractometer | Bruker SMART APEX CCD area-detector diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 7319, 3233, 1574 |
Rint | 0.052 |
(sin θ/λ)max (Å−1) | 0.604 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.041, 0.085, 0.84 |
No. of reflections | 3233 |
No. of parameters | 199 |
No. of restraints | 1 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.11, −0.10 |
Computer programs: SMART (Bruker, 1999), SAINT (Bruker, 1999), SHELXTL (Sheldrick, 2008).
O1—C1 | 1.2173 (18) | N1—C5 | 1.4310 (19) |
O2—C1 | 1.3543 (18) | C1—C2 | 1.419 (2) |
N1—C3 | 1.3439 (19) | C2—C3 | 1.350 (2) |
C3—N1—C5 | 125.68 (14) | C3—C2—C1 | 124.19 (16) |
O1—C1—C2 | 126.24 (17) | N1—C3—C2 | 122.83 (15) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O1 | 0.894 (8) | 2.020 (12) | 2.7402 (18) | 136.8 (13) |
N1—H1···O1i | 0.894 (8) | 2.677 (13) | 3.3371 (18) | 131.5 (12) |
Symmetry code: (i) −x+1, −y, −z+1. |
Acknowledgements
MAV and AC thank DGAPA–UNAM for financial support (PAPIIT IN203209) and CONACyT (Fellowship 229448).
References
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Several methods have been carried out in the β-enaminoketones and β-enaminoesters preparations, for instances; catalysis by silica-supported antimony (III) chloride (Zhang & Yang, 2009), the use of Lewis acids (Bartoli, et al. 2004) solid acids such as montmorillonite K10 (Braibante, et al. 2006). Is necessary to improve this reaction, due to the named compounds are important precursors in organic synthesis, these are particularly useful as they can be further transformed to key intermediates of several pharmaceutical products (Michael et al., 1999). They have been utilized for the preparation of different important aminoacids (Palmieri et al., 1996), peptides and alkaloids (David et al., 1999). In continuation of our work in enaminoesters synthesis (Amézquita-Valencia, et al. 2009), we describe the structure of title compound (I) obtained using a Mexican bentonitic clay as catalist.
The structure with numbering scheme of the title compound is shown in fig. 1. The 2,6-diisopropylphenyl substituent is almost perpendicular to the β-enaminoester function (dihedral angle 87.5°), similar to described in ethyl 3-(2,6-dimethylphenylamino)but-2-enoate (Amézquita-Valencia, et al. 2009). A strong intramolecular N—H···O hydrogen bond is present in the structure, in addition, the molecules are linked by centrosymmetric intermolecular N—H···O hydrogen bond, the symmetry code is 1-x, -y 1-z, fig. 2.