Methyl (E)-3-acet­amido-2-pentenoate

The title compound, C₈H₁₃NO₃, is an E isomer and there are two mol­ecules in the asymmetric unit. The mol­ecules are assembled into chains, along the a axis, via intermolecular interactions.

Key indicators

• Single-crystal X-ray study
• T = 294 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.059
• wR factor = 0.155
• Data-to-parameter ratio = 19.3

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

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S1. Comment

The title compound, (I), is one of the products obtained from reaction of methyl 3-amine-2-pentenoate with acetic anhydride at reflux for 24 h. This prochiral olefin is a model substrate studied in the asymmetric hydrogenation reaction (Hackler et al., 1985; Lubell et al., 1991). The structure determination of (I) was conducted in order to obtain more stereochemical information about the behaviours of these kinds of substrates in hydrogenation reaction. The crystal structure of (I) contains two independent molecules in the asymmetric unit (Fig. 1). A pairwise comparison between these two molecules shows no significant differences in their bond lengths or angles although the conformations of the two molecules are different (Table 1). The C1—C2 bond distance of 1.338 (3) Å is indicative of double-bond character. The angles of C1—C2—C3 [125.1 (2)°], C2—C1—C5 [124.8 (2)°] are larger and N1—C1—C5 [112.0 (2)°] smaller than 120°. This results in a close mutual repulsion between the ethyl group on C1 and carbonyl group on C3.

The molecules are interconnected by N—H···O hydrogen bonding in the crystal (Table 2). As illustrated in Fig. 2, the hydrogen bonding links the molecules along the a axis.

S2. Experimental

The title compound was synthesized according to the literature (Zhu et al., 1999). A crystal suitable for X-ray analysis was slowly grown in a mixed solvent of ethyl acetate and hexane at room temperature. ¹H NMR (400 MHz, acetone-d₆, Bruker): δ 1.09–1.12 (t, J = 7.5 Hz, 3H), 2.06 (s, 3H), 2.71–2.77 (q, J = 7.5 Hz, 2H), 3.59 (s, 3H), 6.87 (s, 1H), 8.75 (br, 1H).

S3. Refinement

H atoms were included in the riding-model approximation, with U_iso values equal to U_eq of the atom to which they were bound.

Computing details

Data collection: SMART (Siemens, 1995); cell refinement: SMART; data reduction: SHELXTL (Siemens, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Figures

	Fig. 1. The molecular structure of (I), showing ellipsoids at the 50% probability level (Siemens, 1995).
	Fig. 2. Packing diagram for (I). Hydrogen bonds are indicated by dashed lines.

(I)

Crystal data

C8H13NO3	F(000) = 736
Mr = 171.19	Dx = 1.220 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 2920 reflections
a = 9.718 (7) Å	θ = 1–27.5°
b = 12.673 (9) Å	µ = 0.09 mm^−1
c = 15.653 (7) Å	T = 294 K
β = 104.825 (15)°	Needle, colorless
V = 1864 (2) Å^3	0.38 × 0.12 × 0.10 mm
Z = 8

Data collection

Siemens CCD area-detector diffractometer	4308 independent reflections
Radiation source: fine-focus sealed tube	1544 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.057
ϕ and ω scans	θmax = 27.6°, θmin = 2.7°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −12→12
Tmin = 0.965, Tmax = 0.991	k = −15→16
12544 measured reflections	l = −16→20

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.059	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.156	H-atom parameters constrained
S = 1.06	w = 1/[σ^2(Fo^2) + (0.05P)^2] where P = (Fo^2 + 2Fc^2)/3
4308 reflections	(Δ/σ)max < 0.001
223 parameters	Δρmax = 0.17 e Å^−3
0 restraints	Δρmin = −0.19 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
O1	0.9833 (2)	0.69319 (16)	0.09679 (19)	0.1094 (9)
O2	1.18911 (19)	0.62579 (15)	0.08953 (14)	0.0753 (6)
O3	1.10959 (18)	0.30060 (14)	0.17560 (15)	0.0760 (7)
N1	0.8894 (2)	0.36964 (16)	0.15820 (14)	0.0540 (6)
H1A	0.8036	0.3530	0.1580	0.065*
C1	0.9105 (2)	0.4745 (2)	0.13860 (18)	0.0507 (7)
C2	1.0278 (3)	0.5087 (2)	0.11740 (17)	0.0516 (7)
H2	1.0956	0.4587	0.1130	0.062*
C3	1.0572 (3)	0.6175 (2)	0.10079 (19)	0.0593 (8)
C4	1.2351 (4)	0.7300 (3)	0.0731 (2)	0.0991 (12)
H4A	1.1591	0.7658	0.0321	0.149*
H4B	1.3160	0.7250	0.0487	0.149*
H4C	1.2608	0.7687	0.1276	0.149*
C5	0.7856 (3)	0.5444 (2)	0.1451 (2)	0.0661 (9)
H5A	0.7403	0.5150	0.1883	0.079*
H5B	0.8202	0.6143	0.1649	0.079*
C6	0.6797 (3)	0.5522 (3)	0.0579 (2)	0.1045 (13)
H6A	0.7240	0.5828	0.0156	0.157*
H6B	0.6016	0.5958	0.0634	0.157*
H6C	0.6451	0.4830	0.0385	0.157*
C7	0.9857 (3)	0.2902 (2)	0.17752 (19)	0.0571 (8)
C8	0.9303 (3)	0.1880 (2)	0.2023 (2)	0.0834 (11)
H8A	0.8976	0.1452	0.1505	0.125*
H8B	0.8528	0.2013	0.2285	0.125*
H8C	1.0049	0.1516	0.2440	0.125*
O4	0.4679 (2)	−0.10593 (16)	0.11316 (17)	0.0964 (8)
O5	0.68342 (19)	−0.04784 (14)	0.11396 (13)	0.0686 (6)
O6	0.60226 (18)	0.29268 (14)	0.16089 (14)	0.0742 (7)
N2	0.3890 (2)	0.22289 (16)	0.16423 (14)	0.0524 (6)
H2A	0.3053	0.2408	0.1677	0.063*
C9	0.4066 (2)	0.1162 (2)	0.14978 (17)	0.0459 (7)
C10	0.5211 (3)	0.07784 (19)	0.12828 (17)	0.0485 (7)
H10	0.5885	0.1258	0.1194	0.058*
C11	0.5477 (3)	−0.0328 (2)	0.11787 (18)	0.0555 (8)
C12	0.7239 (3)	−0.1552 (2)	0.1038 (2)	0.0859 (11)
H12A	0.7171	−0.1954	0.1546	0.129*
H12B	0.8202	−0.1570	0.0986	0.129*
H12C	0.6616	−0.1848	0.0517	0.129*
C13	0.2837 (3)	0.0516 (2)	0.16213 (18)	0.0543 (8)
H13A	0.2458	0.0842	0.2074	0.065*
H13B	0.3178	−0.0181	0.1828	0.065*
C14	0.1658 (3)	0.0409 (2)	0.0786 (2)	0.0779 (10)
H14A	0.1314	0.1096	0.0578	0.117*
H14B	0.0895	0.0002	0.0906	0.117*
H14C	0.2015	0.0059	0.0343	0.117*
C15	0.4841 (3)	0.3031 (2)	0.17365 (19)	0.0549 (8)
C16	0.4349 (3)	0.4060 (2)	0.2011 (2)	0.0767 (10)
H16A	0.5118	0.4394	0.2433	0.115*
H16B	0.3571	0.3942	0.2274	0.115*
H16C	0.4039	0.4507	0.1502	0.115*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0791 (16)	0.0514 (15)	0.214 (3)	0.0174 (13)	0.0671 (18)	0.0217 (15)
O2	0.0552 (13)	0.0565 (13)	0.1210 (18)	−0.0154 (10)	0.0349 (12)	0.0012 (12)
O3	0.0336 (11)	0.0586 (13)	0.144 (2)	0.0072 (9)	0.0368 (12)	0.0141 (12)
N1	0.0251 (11)	0.0437 (14)	0.0964 (18)	0.0005 (10)	0.0211 (12)	0.0040 (12)
C1	0.0295 (14)	0.0463 (18)	0.074 (2)	0.0026 (13)	0.0094 (14)	0.0000 (14)
C2	0.0353 (15)	0.0428 (17)	0.078 (2)	0.0040 (13)	0.0174 (15)	0.0014 (14)
C3	0.0494 (18)	0.049 (2)	0.081 (2)	−0.0011 (15)	0.0205 (17)	−0.0001 (16)
C4	0.093 (3)	0.067 (2)	0.144 (3)	−0.039 (2)	0.044 (2)	0.000 (2)
C5	0.0452 (17)	0.056 (2)	0.097 (3)	0.0040 (14)	0.0190 (18)	0.0010 (16)
C6	0.058 (2)	0.104 (3)	0.132 (4)	0.023 (2)	−0.011 (2)	−0.009 (2)
C7	0.0365 (16)	0.0494 (19)	0.091 (2)	0.0052 (14)	0.0263 (17)	0.0047 (15)
C8	0.057 (2)	0.058 (2)	0.146 (3)	0.0071 (16)	0.046 (2)	0.019 (2)
O4	0.0780 (16)	0.0512 (14)	0.172 (2)	−0.0170 (12)	0.0546 (16)	−0.0154 (14)
O5	0.0581 (13)	0.0486 (13)	0.1061 (17)	0.0146 (10)	0.0337 (12)	−0.0038 (11)
O6	0.0350 (11)	0.0538 (13)	0.144 (2)	−0.0060 (9)	0.0408 (12)	−0.0171 (12)
N2	0.0267 (11)	0.0465 (15)	0.0864 (18)	0.0005 (10)	0.0189 (12)	−0.0055 (12)
C9	0.0323 (14)	0.0467 (18)	0.0577 (18)	−0.0035 (13)	0.0099 (13)	−0.0001 (14)
C10	0.0366 (15)	0.0399 (17)	0.072 (2)	−0.0009 (13)	0.0185 (14)	−0.0043 (14)
C11	0.0519 (18)	0.049 (2)	0.070 (2)	0.0029 (16)	0.0225 (16)	0.0013 (16)
C12	0.104 (3)	0.054 (2)	0.110 (3)	0.0340 (19)	0.046 (2)	0.0111 (18)
C13	0.0395 (16)	0.0590 (19)	0.066 (2)	−0.0068 (13)	0.0170 (15)	0.0015 (14)
C14	0.0469 (18)	0.094 (3)	0.089 (3)	−0.0220 (16)	0.0105 (18)	−0.0117 (19)
C15	0.0360 (16)	0.0464 (18)	0.085 (2)	−0.0009 (13)	0.0204 (16)	−0.0071 (15)
C16	0.0472 (18)	0.057 (2)	0.129 (3)	0.0012 (15)	0.0281 (19)	−0.0221 (19)

Geometric parameters (Å, º)

O1—C3	1.190 (3)	O4—C11	1.198 (3)
O2—C3	1.342 (3)	O5—C11	1.349 (3)
O2—C4	1.438 (3)	O5—C12	1.436 (3)
O3—C7	1.219 (3)	O6—C15	1.222 (3)
N1—C7	1.355 (3)	N2—C15	1.356 (3)
N1—C1	1.391 (3)	N2—C9	1.388 (3)
N1—H1A	0.8600	N2—H2A	0.8600
C1—C2	1.338 (3)	C9—C10	1.334 (3)
C1—C5	1.527 (3)	C9—C13	1.500 (3)
C2—C3	1.445 (4)	C10—C11	1.443 (3)
C2—H2	0.9300	C10—H10	0.9300
C4—H4A	0.9600	C12—H12A	0.9600
C4—H4B	0.9600	C12—H12B	0.9600
C4—H4C	0.9600	C12—H12C	0.9600
C5—C6	1.488 (4)	C13—C14	1.508 (4)
C5—H5A	0.9700	C13—H13A	0.9700
C5—H5B	0.9700	C13—H13B	0.9700
C6—H6A	0.9600	C14—H14A	0.9600
C6—H6B	0.9600	C14—H14B	0.9600
C6—H6C	0.9600	C14—H14C	0.9600
C7—C8	1.492 (4)	C15—C16	1.489 (3)
C8—H8A	0.9600	C16—H16A	0.9600
C8—H8B	0.9600	C16—H16B	0.9600
C8—H8C	0.9600	C16—H16C	0.9600
C3—O2—C4	116.5 (2)	C11—O5—C12	115.9 (2)
C7—N1—C1	128.8 (2)	C15—N2—C9	129.7 (2)
C7—N1—H1A	115.6	C15—N2—H2A	115.1
C1—N1—H1A	115.6	C9—N2—H2A	115.1
C2—C1—N1	123.2 (2)	C10—C9—N2	122.8 (2)
C2—C1—C5	124.8 (2)	C10—C9—C13	125.2 (2)
N1—C1—C5	112.0 (2)	N2—C9—C13	112.0 (2)
C1—C2—C3	125.1 (2)	C9—C10—C11	124.6 (2)
C1—C2—H2	117.5	C9—C10—H10	117.7
C3—C2—H2	117.5	C11—C10—H10	117.7
O1—C3—O2	120.9 (3)	O4—C11—O5	120.9 (3)
O1—C3—C2	129.4 (3)	O4—C11—C10	128.8 (3)
O2—C3—C2	109.7 (2)	O5—C11—C10	110.3 (2)
O2—C4—H4A	109.5	O5—C12—H12A	109.5
O2—C4—H4B	109.5	O5—C12—H12B	109.5
H4A—C4—H4B	109.5	H12A—C12—H12B	109.5
O2—C4—H4C	109.5	O5—C12—H12C	109.5
H4A—C4—H4C	109.5	H12A—C12—H12C	109.5
H4B—C4—H4C	109.5	H12B—C12—H12C	109.5
C6—C5—C1	110.6 (2)	C9—C13—C14	113.0 (2)
C6—C5—H5A	109.5	C9—C13—H13A	109.0
C1—C5—H5A	109.5	C14—C13—H13A	109.0
C6—C5—H5B	109.5	C9—C13—H13B	109.0
C1—C5—H5B	109.5	C14—C13—H13B	109.0
H5A—C5—H5B	108.1	H13A—C13—H13B	107.8
C5—C6—H6A	109.5	C13—C14—H14A	109.5
C5—C6—H6B	109.5	C13—C14—H14B	109.5
H6A—C6—H6B	109.5	H14A—C14—H14B	109.5
C5—C6—H6C	109.5	C13—C14—H14C	109.5
H6A—C6—H6C	109.5	H14A—C14—H14C	109.5
H6B—C6—H6C	109.5	H14B—C14—H14C	109.5
O3—C7—N1	123.0 (2)	O6—C15—N2	123.0 (2)
O3—C7—C8	121.7 (2)	O6—C15—C16	121.7 (2)
N1—C7—C8	115.4 (2)	N2—C15—C16	115.3 (2)
C7—C8—H8A	109.5	C15—C16—H16A	109.5
C7—C8—H8B	109.5	C15—C16—H16B	109.5
H8A—C8—H8B	109.5	H16A—C16—H16B	109.5
C7—C8—H8C	109.5	C15—C16—H16C	109.5
H8A—C8—H8C	109.5	H16A—C16—H16C	109.5
H8B—C8—H8C	109.5	H16B—C16—H16C	109.5
C7—N1—C1—C2	14.8 (4)	C15—N2—C9—C10	−11.3 (4)
C7—N1—C1—C5	−164.6 (3)	C15—N2—C9—C13	168.1 (3)
N1—C1—C2—C3	−176.8 (3)	N2—C9—C10—C11	176.1 (2)
C5—C1—C2—C3	2.6 (4)	C13—C9—C10—C11	−3.2 (4)
C4—O2—C3—O1	0.3 (4)	C12—O5—C11—O4	0.1 (4)
C4—O2—C3—C2	−179.4 (2)	C12—O5—C11—C10	179.8 (2)
C1—C2—C3—O1	−5.5 (5)	C9—C10—C11—O4	12.2 (5)
C1—C2—C3—O2	174.2 (3)	C9—C10—C11—O5	−167.5 (3)
C2—C1—C5—C6	88.7 (3)	C10—C9—C13—C14	−91.6 (3)
N1—C1—C5—C6	−91.8 (3)	N2—C9—C13—C14	89.0 (3)
C1—N1—C7—O3	−4.0 (5)	C9—N2—C15—O6	8.2 (5)
C1—N1—C7—C8	175.5 (3)	C9—N2—C15—C16	−171.7 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O6	0.86	2.11	2.967 (3)	173
N2—H2A···O3^i	0.86	2.08	2.936 (3)	174

Symmetry code: (i) x−1, y, z.