anti-Ethyl aceto­hydroximate

In the crystal structure of the title compound, C₄H₉NO₂, the O—H⋯N hydrogen bonds link the mol­ecules into supra­molecular chains extending along the b-axis direction. The conformation of the NOH group in the nearly planar (r.m.s. deviation = 0.0546 Å) ethyl aceto­hydroximate mol­ecule is trans to N=C.

Related literature

For related structures, see: Kjaer et al. (1977); Larsen (1971). For studies of the IR spectra of hydrogen bonding in oxime derivatives, see: Flakus et al. (2012). For typical bond distances, see: Allen et al. (1987). For hydrogen-bond motifs, see: Bernstein et al. (1995); Etter et al. (1990).

Experimental

Crystal data

• C₄H₉NO₂

• M_r = 103.12

• Monoclinic, C 2/c

• a = 19.9481 (9) Å

• b = 4.4138 (1) Å

• c = 13.3277 (5) Å

• β = 109.027 (4)°

• V = 1109.35 (7) ų

• Z = 8

• Mo Kα radiation

• μ = 0.10 mm⁻¹

• T = 100 K

• 0.52 × 0.18 × 0.14 mm

Data collection

• Oxford Diffraction Xcalibur diffractometer with a Sapphire3 detector

• Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006) T_min = 0.505, T_max = 1.000

• 6699 measured reflections

• 970 independent reflections

• 868 reflections with I > 2σ(I)

• R_int = 0.025

Refinement

• R[F² > 2σ(F²)] = 0.034

• wR(F²) = 0.098

• S = 1.08

• 970 reflections

• 69 parameters

• H atoms treated by a mixture of independent and constrained refinement

• Δρ_max = 0.22 e Å⁻³

• Δρ_min = −0.22 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N1^i	0.871 (19)	1.954 (19)	2.8196 (14)	172.4 (16)
Symmetry code: (i) .

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis CCD; data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Supporting information

S1. Comment

Anti-ethyl acetohydroximate [systematic name: ethyl N-hydroxyacetimidate], (I), was investigated in a continuation of our studies of the IR spectra of hydrogen bonding in oxime derivatives (Flakus et al., 2012). In order to study interactions occurring via hydrogen bonds and molecular packing in this compound, we have now determined the structure of (I) using diffraction data collected at 100 K. Until now, the structures of syn-methyl acetohydroximate and syn- and anti-ethyl benzohydroximate were determined (Kjaer et al., 1977; Larsen et al., 1971). The crystal structure of syn-methyl acetohydroximate is composed of layers of molecules, which form cyclic, hydrogen-bonded trimers, whereas the crystals of syn- and anti-ethyl benzohydroximate are composed of dimers formed by pairs of O—H···N hydrogen- bonded molecules.

The molecule of (I) is nearly planar (r.m.s. deviations 0.0546 Å for all non-H atoms). The lengths of the bonds C=N (1.2771 (17) Å) and N—O (1.4286 (13) Å) in (I) are comparable to the mean values found in other oximes (C=N 1.281 Å; N—O 1.394 Å) (Allen et al., 1987). The conformation of the NOH group in the planar ethyl acetohydroximate molecule is trans to N=C. In the crystal, O—H···N are observed forming infinite chains along the b axis (Fig. 2) with a graph-set motif of C(3) (Etter et al., 1990; Bernstein et al., 1995).

Related literature

For related structures, see: Kjaer et al. (1977); Larsen (1971). For studies of the IR spectra of hydrogen bonding in oxime derivatives, see: Flakus et al. (2012). For typical bond distances, see: Allen et al. (1987). For hydrogen-bond motifs, see: Bernstein et al. (1995); Etter et al. (1990).

S2. Experimental

Ethyl acetohydroximate was purchased from Aldrich-Sigma. Crystals of title compound, suitable for X-ray diffraction, were selected directly from purchased sample.

S3. Refinement

The H atoms were introduced in geometrically idealized positions with C—H distances of 0.99 Å and U_iso(H) values set at 1.2U_eq(C) for methylene group or 0.98 Å and with U_iso(H) values set at 1.5U_eq(C) for methyl groups. The H atom which takes part in hydrogen bonding was located in a difference Fourier map and was refined with U_iso(H) value set at 1.5U_eq(O).

Computing details

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis RED (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures

	Fig. 1. The asymmetric unit of (I), with the atom-numbering scheme, showing 50% probability displacement ellipsoids. H atoms are shown as small spheres of arbitrary radius.
	Fig. 2. Part of the crystal structure of (I), showing the C(3) chains. The red lines indicate the hydrogen-bonding interactions. For the sake of clarity, all H atoms bonded to C atoms were omitted.

Ethyl N-hydroxyethanecarboximidate

Crystal data

C4H9NO2	F(000) = 448
Mr = 103.12	Dx = 1.235 Mg m^−3
Monoclinic, C2/c	Melting point = 296–298 K
Hall symbol: -C 2yc	Mo Kα radiation, λ = 0.71073 Å
a = 19.9481 (9) Å	Cell parameters from 6376 reflections
b = 4.4138 (1) Å	θ = 3.1–34.4°
c = 13.3277 (5) Å	µ = 0.10 mm^−1
β = 109.027 (4)°	T = 100 K
V = 1109.35 (7) Å^3	Needle, colourless
Z = 8	0.52 × 0.18 × 0.14 mm

Data collection

Oxford Diffraction Xcalibur diffractometer with a Sapphire3 detector	970 independent reflections
Radiation source: fine-focus sealed tube	868 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.025
Detector resolution: 16.0328 pixels mm^-1	θmax = 25.1°, θmin = 3.2°
ω–scan	h = −22→23
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)	k = −2→5
Tmin = 0.505, Tmax = 1.000	l = −15→15
6699 measured reflections

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)] = 0.034	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.098	H atoms treated by a mixture of independent and constrained refinement
S = 1.08	w = 1/[σ^2(Fo^2) + (0.0616P)^2 + 0.5949P] where P = (Fo^2 + 2Fc^2)/3
970 reflections	(Δ/σ)max < 0.001
69 parameters	Δρmax = 0.22 e Å^−3
0 restraints	Δρmin = −0.22 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	0.31644 (5)	0.6668 (2)	0.82875 (7)	0.0201 (3)
O2	0.39491 (4)	0.1706 (2)	0.69431 (7)	0.0185 (3)
N1	0.31725 (5)	0.4501 (2)	0.74954 (8)	0.0165 (3)
C1	0.38102 (7)	0.3704 (3)	0.76216 (10)	0.0158 (3)
C2	0.44623 (7)	0.4799 (3)	0.84598 (10)	0.0215 (3)
H2A	0.4568	0.6871	0.8294	0.032*
H2B	0.4862	0.3472	0.8486	0.032*
H2C	0.4385	0.4774	0.9149	0.032*
C3	0.33586 (7)	0.0728 (3)	0.60358 (10)	0.0187 (3)
H3A	0.3103	0.2503	0.5636	0.022*
H3B	0.3022	−0.0497	0.6271	0.022*
C4	0.36699 (8)	−0.1145 (3)	0.53500 (11)	0.0235 (3)
H4A	0.3987	0.0118	0.5100	0.035*
H4B	0.3287	−0.1929	0.4739	0.035*
H4C	0.3938	−0.2843	0.5765	0.035*
H1	0.2735 (10)	0.740 (4)	0.8065 (13)	0.035*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0168 (5)	0.0243 (5)	0.0190 (5)	0.0038 (4)	0.0054 (4)	−0.0041 (4)
O2	0.0153 (5)	0.0230 (5)	0.0163 (5)	0.0012 (3)	0.0041 (4)	−0.0017 (4)
N1	0.0170 (6)	0.0172 (6)	0.0154 (6)	−0.0001 (4)	0.0052 (4)	0.0006 (4)
C1	0.0167 (7)	0.0174 (6)	0.0140 (6)	0.0000 (5)	0.0062 (5)	0.0034 (5)
C2	0.0152 (7)	0.0290 (7)	0.0193 (7)	0.0011 (5)	0.0042 (5)	−0.0014 (6)
C3	0.0175 (7)	0.0201 (7)	0.0164 (7)	−0.0019 (5)	0.0026 (5)	0.0002 (5)
C4	0.0282 (7)	0.0241 (7)	0.0188 (7)	−0.0025 (6)	0.0086 (6)	−0.0006 (5)

Geometric parameters (Å, º)

O1—N1	1.4286 (13)	C2—H2C	0.9800
O1—H1	0.871 (19)	C3—C4	1.5082 (17)
O2—C1	1.3547 (15)	C3—H3A	0.9900
O2—C3	1.4517 (15)	C3—H3B	0.9900
N1—C1	1.2771 (17)	C4—H4A	0.9800
C1—C2	1.4922 (17)	C4—H4B	0.9800
C2—H2A	0.9800	C4—H4C	0.9800
C2—H2B	0.9800
N1—O1—H1	104.1 (11)	O2—C3—C4	106.57 (10)
C1—O2—C3	117.55 (9)	O2—C3—H3A	110.4
C1—N1—O1	109.76 (10)	C4—C3—H3A	110.4
N1—C1—O2	120.21 (12)	O2—C3—H3B	110.4
N1—C1—C2	126.66 (12)	C4—C3—H3B	110.4
O2—C1—C2	113.11 (10)	H3A—C3—H3B	108.6
C1—C2—H2A	109.5	C3—C4—H4A	109.5
C1—C2—H2B	109.5	C3—C4—H4B	109.5
H2A—C2—H2B	109.5	H4A—C4—H4B	109.5
C1—C2—H2C	109.5	C3—C4—H4C	109.5
H2A—C2—H2C	109.5	H4A—C4—H4C	109.5
H2B—C2—H2C	109.5	H4B—C4—H4C	109.5
O1—N1—C1—O2	−178.49 (9)	C3—O2—C1—C2	−174.04 (10)
O1—N1—C1—C2	0.24 (17)	C1—O2—C3—C4	173.10 (10)
C3—O2—C1—N1	4.85 (16)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1^i	0.871 (19)	1.954 (19)	2.8196 (14)	172.4 (16)

Symmetry code: (i) −x+1/2, y+1/2, −z+3/2.