2-Meth­oxy-2-methyl­imidazolidine-4,5-dione

The asymmetric unit of the title compound, C₅H₈N₂O₃, contains two mol­ecules. The crystal structure features N—H...O=C hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 150 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.062
• wR factor = 0.146
• Data-to-parameter ratio = 16.3

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT180_ALERT_3_C Check Cell Rounding: # of Values Ending with 0 =          3
PLAT369_ALERT_2_C Long   C(sp2)-C(sp2) Bond  C1     -   C2     ...       1.53 Ang.
PLAT369_ALERT_2_C Long   C(sp2)-C(sp2) Bond  C6     -   C7     ...       1.53 Ang.
PLAT432_ALERT_2_C Short Inter X...Y Contact  O3     ..  C6      ..       2.98 Ang.
PLAT432_ALERT_2_C Short Inter X...Y Contact  O3     ..  C7      ..       3.01 Ang.
PLAT480_ALERT_4_C Long H...A H-Bond Reported H3     ..  O1      ..       2.64 Ang.

Alert level G
PLAT793_ALERT_1_G Check the Absolute Configuration of C8     = ...          S

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   6 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   4 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 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

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S1. Comment

2-Methoxy-2-methylimidazolidine-4,5-dione is the only known example of 2-alkoxy-2-alkylimidazolidine-4,5-diones. It is an intermediate of the synthesis of the low-sensitivity energetic material 2,2-dinitroethene-1,1-diamine (Latypov et al., 1999).

The title compound (I) has been obtained as colourless crystals from a saturated methanol solution.

Two independent molecules which are positioned with an interplanar (ring to ring) angle of 88.49 (10)° are found in the asymmetric unit. The five-membered rings are formed (see Figure 1) by two N(H)—C=O fragments and one ipso carbon connected to both methoxy and methyl groups. The structure of similar cyclic compounds were determined previously (Stasko et al., 2002; Fryer et al., 1977). In both cases, a spiro derivative of imidazoline-4,5-dione (II) and benzodiazepine-1,2-dione (III) reveals very similar interatomic distances and bonding angles to those found in the title compound.

The C—O distances found in (I) [1.217 (3), 1.216 (3), 1.220 (3), and 1.216 (3) Å] are typical for double bonds between these elements. All N—H groups are bonded to C=O fragments in a similar manner to that usually found in peptides. The distances [1.531 (3) Å and 1.528 (3) Å] between the carbon atoms of C=O fragments are a little longer than found in the comparable compounds (II) and (III). All remaining interatomic distances and bonding angles are in line with those found for (II) and (III) previously.

Compound (I) forms an extensive three-dimensional network through the N—H···O=C hydrogen bonding (see Figure 2).

Related literature

For related literature, see: Fryer et al. (1977); Latypov et al. (1998, 1999); Stasko et al. (2002).

S2. Experimental

Compound (I) was prepared according to a reported method (Latypov et al., 1998). Elemental analysis and spectroscopic data (NMR and IR) were identical to data given in the literature (Latypov et al., 1998). Crystals suitable for X-ray crystallographic analysis were obtained via solvent evaporation (methanol).

S3. Refinement

All H atoms were positioned geometrically and refined as riding on their parent C or N atoms, with N—H = 0.86 Å, U_iso(H) = 1.2U_eq(C); C—H = 0.96 Å, U_iso(H) = 1.5U_e.g(C).

Computing details

Data collection: COLLECT (Hooft, 1998) and DENZO (Otwinowski & Minor, 1997); cell refinement: COLLECT and DENZO; data reduction: COLLECT and DENZO; program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. Perspective view of the two independent molecules of (I) in the asymmetric unit, with 50% probability displacement ellipsoids (arbitrary spheres for H atoms).
	Fig. 2. View of the hydrogen bonding (dashed lines) in (I).

2-Methoxy-2-methylimidazolidine-4,5-dione

Crystal data

C5H8N2O3	F(000) = 608
Mr = 144.13	Dx = 1.477 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 13590 reflections
a = 12.4940 (6) Å	θ = 1–27.5°
b = 6.1930 (4) Å	µ = 0.12 mm^−1
c = 16.8170 (9) Å	T = 150 K
β = 95.054 (4)°	Block, colourless
V = 1296.16 (13) Å^3	0.49 × 0.19 × 0.15 mm
Z = 8

Data collection

Bruke–Nonius KappaCCD area-detector diffractometer	2951 independent reflections
Radiation source: fine-focus sealed tube	2060 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.068
Detector resolution: 9.091 pixels mm^-1	θmax = 27.5°, θmin = 2.4°
ϕ and ω scans	h = −16→16
Absorption correction: integration Gaussian integration (Coppens, 1970)	k = −7→8
Tmin = 0.964, Tmax = 0.989	l = −21→21
12836 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)] = 0.063	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.146	H-atom parameters constrained
S = 1.12	w = 1/[σ^2(Fo^2) + (0.0472P)^2 + 1.5623P] where P = (Fo^2 + 2Fc^2)/3
2951 reflections	(Δ/σ)max < 0.001
181 parameters	Δρmax = 0.50 e Å^−3
0 restraints	Δρmin = −0.32 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	0.12247 (15)	0.6735 (3)	−0.00306 (11)	0.0255 (4)
O4	0.82756 (14)	0.1748 (3)	0.25416 (10)	0.0241 (4)
O5	0.60291 (15)	0.1821 (3)	0.29300 (11)	0.0284 (5)
O6	0.63045 (16)	0.5268 (3)	0.06070 (11)	0.0302 (5)
N1	0.15534 (18)	0.4369 (3)	0.10251 (13)	0.0246 (5)
H1	0.1729	0.5280	0.1400	0.030*
O3	0.24709 (15)	0.1223 (3)	0.15056 (11)	0.0289 (5)
O2	0.09293 (15)	0.2734 (3)	−0.09169 (10)	0.0259 (4)
C6	0.75687 (19)	0.2888 (4)	0.22195 (14)	0.0186 (5)
N3	0.76312 (17)	0.4351 (3)	0.16439 (12)	0.0210 (5)
H3	0.8214	0.4606	0.1424	0.025*
N2	0.12607 (17)	0.1272 (3)	0.03429 (12)	0.0228 (5)
H2	0.1210	−0.0076	0.0222	0.027*
N4	0.59112 (17)	0.4362 (4)	0.19236 (13)	0.0240 (5)
H4	0.5233	0.4619	0.1903	0.029*
C1	0.13122 (19)	0.4949 (4)	0.02705 (15)	0.0187 (5)
C7	0.6399 (2)	0.2909 (4)	0.24181 (14)	0.0196 (5)
C8	0.6631 (2)	0.5476 (4)	0.14202 (15)	0.0224 (6)
C3	0.1494 (2)	0.2047 (4)	0.11601 (15)	0.0235 (6)
C2	0.11345 (19)	0.2841 (4)	−0.01977 (14)	0.0188 (5)
C9	0.6684 (2)	0.7859 (4)	0.15861 (17)	0.0294 (6)
H9A	0.6906	0.8093	0.2141	0.044*
H9B	0.5988	0.8489	0.1459	0.044*
H9C	0.7193	0.8517	0.1265	0.044*
C4	0.0641 (2)	0.1466 (5)	0.17123 (16)	0.0287 (6)
H4A	−0.0043	0.2008	0.1494	0.043*
H4B	0.0822	0.2099	0.2228	0.043*
H4C	0.0603	−0.0075	0.1764	0.043*
C10	0.6166 (2)	0.3104 (5)	0.03054 (16)	0.0331 (7)
H10A	0.5943	0.3151	−0.0255	0.050*
H10B	0.5629	0.2378	0.0581	0.050*
H10C	0.6835	0.2337	0.0389	0.050*
C5	0.3385 (2)	0.1707 (5)	0.10905 (16)	0.0301 (6)
H5A	0.4013	0.1081	0.1369	0.045*
H5B	0.3472	0.3245	0.1062	0.045*
H5C	0.3286	0.1123	0.0560	0.045*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0335 (10)	0.0138 (9)	0.0294 (10)	0.0033 (8)	0.0036 (8)	0.0033 (8)
O4	0.0245 (9)	0.0237 (10)	0.0241 (9)	0.0044 (8)	0.0018 (7)	0.0062 (8)
O5	0.0292 (10)	0.0268 (11)	0.0304 (10)	−0.0065 (9)	0.0093 (8)	0.0040 (8)
O6	0.0388 (11)	0.0277 (11)	0.0228 (10)	0.0054 (9)	−0.0053 (8)	0.0022 (8)
N1	0.0380 (13)	0.0143 (11)	0.0203 (11)	0.0007 (10)	−0.0046 (9)	−0.0039 (9)
O3	0.0262 (10)	0.0329 (11)	0.0274 (10)	0.0030 (9)	0.0012 (8)	0.0079 (8)
O2	0.0316 (10)	0.0275 (11)	0.0183 (9)	−0.0044 (8)	−0.0003 (7)	−0.0014 (8)
C6	0.0218 (12)	0.0174 (13)	0.0167 (11)	−0.0003 (11)	0.0031 (9)	−0.0007 (10)
N3	0.0191 (10)	0.0229 (12)	0.0217 (11)	0.0021 (9)	0.0056 (8)	0.0043 (9)
N2	0.0316 (12)	0.0116 (11)	0.0244 (11)	0.0003 (9)	−0.0020 (9)	−0.0028 (9)
N4	0.0170 (10)	0.0280 (13)	0.0273 (11)	0.0017 (9)	0.0040 (9)	0.0014 (10)
C1	0.0176 (12)	0.0162 (13)	0.0226 (13)	0.0015 (10)	0.0033 (10)	−0.0016 (10)
C7	0.0225 (12)	0.0165 (13)	0.0200 (12)	−0.0023 (10)	0.0026 (10)	−0.0037 (10)
C8	0.0240 (13)	0.0228 (14)	0.0203 (13)	0.0040 (11)	0.0008 (10)	0.0025 (10)
C3	0.0265 (13)	0.0201 (14)	0.0230 (13)	0.0018 (11)	−0.0032 (10)	0.0010 (10)
C2	0.0163 (11)	0.0173 (13)	0.0229 (12)	−0.0001 (10)	0.0015 (9)	−0.0023 (10)
C9	0.0371 (15)	0.0200 (15)	0.0311 (14)	0.0044 (12)	0.0015 (12)	0.0017 (11)
C4	0.0226 (13)	0.0323 (16)	0.0311 (15)	0.0002 (12)	0.0017 (11)	0.0064 (12)
C10	0.0396 (16)	0.0318 (17)	0.0265 (14)	−0.0011 (14)	−0.0046 (12)	−0.0058 (12)
C5	0.0240 (13)	0.0352 (17)	0.0318 (14)	0.0002 (12)	0.0064 (11)	0.0088 (13)

Geometric parameters (Å, º)

O1—C1	1.217 (3)	N4—C7	1.335 (3)
O4—C6	1.220 (3)	N4—C8	1.461 (3)
O5—C7	1.216 (3)	N4—H4	0.8599
O6—C8	1.398 (3)	C1—C2	1.531 (3)
O6—C10	1.438 (3)	C8—C9	1.502 (4)
N1—C1	1.328 (3)	C3—C4	1.517 (4)
N1—C3	1.459 (3)	C9—H9A	0.960
N1—H1	0.860	C9—H9B	0.960
O3—C3	1.401 (3)	C9—H9C	0.960
O3—C5	1.422 (3)	C4—H4A	0.960
O2—C2	1.216 (3)	C4—H4B	0.960
C6—N3	1.333 (3)	C4—H4C	0.960
C6—C7	1.528 (3)	C10—H10A	0.960
N3—C8	1.452 (3)	C10—H10B	0.960
N3—H3	0.860	C10—H10C	0.960
N2—C2	1.330 (3)	C5—H5A	0.960
N2—C3	1.461 (3)	C5—H5B	0.960
N2—H2	0.8599	C5—H5C	0.960
C8—O6—C10	116.5 (2)	N1—C3—N2	100.73 (19)
C1—N1—C3	113.9 (2)	O3—C3—C4	107.1 (2)
C1—N1—H1	123.0	N1—C3—C4	112.1 (2)
C3—N1—H1	123.1	N2—C3—C4	113.9 (2)
C3—O3—C5	115.3 (2)	O2—C2—N2	129.9 (2)
O4—C6—N3	129.0 (2)	O2—C2—C1	124.5 (2)
O4—C6—C7	125.3 (2)	N2—C2—C1	105.6 (2)
N3—C6—C7	105.7 (2)	C8—C9—H9A	109.5
C6—N3—C8	114.2 (2)	C8—C9—H9B	109.5
C6—N3—H3	122.9	H9A—C9—H9B	109.5
C8—N3—H3	122.9	C8—C9—H9C	109.5
C2—N2—C3	113.9 (2)	H9A—C9—H9C	109.5
C2—N2—H2	123.1	H9B—C9—H9C	109.5
C3—N2—H2	123.1	C3—C4—H4A	109.5
C7—N4—C8	114.1 (2)	C3—C4—H4B	109.5
C7—N4—H4	122.9	H4A—C4—H4B	109.5
C8—N4—H4	122.9	C3—C4—H4C	109.5
O1—C1—N1	130.4 (2)	H4A—C4—H4C	109.5
O1—C1—C2	123.9 (2)	H4B—C4—H4C	109.5
N1—C1—C2	105.7 (2)	O6—C10—H10A	109.5
O5—C7—N4	129.3 (2)	O6—C10—H10B	109.5
O5—C7—C6	125.5 (2)	H10A—C10—H10B	109.5
N4—C7—C6	105.2 (2)	O6—C10—H10C	109.5
O6—C8—N3	112.3 (2)	H10A—C10—H10C	109.5
O6—C8—N4	112.5 (2)	H10B—C10—H10C	109.5
N3—C8—N4	100.5 (2)	O3—C5—H5A	109.5
O6—C8—C9	106.1 (2)	O3—C5—H5B	109.5
N3—C8—C9	113.6 (2)	H5A—C5—H5B	109.5
N4—C8—C9	112.1 (2)	O3—C5—H5C	109.5
O3—C3—N1	111.7 (2)	H5A—C5—H5C	109.5
O3—C3—N2	111.4 (2)	H5B—C5—H5C	109.5

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N4—H4···O5^i	0.86	2.12	2.892 (3)	149
N1—H1···O4^i	0.86	2.00	2.817 (3)	159
N3—H3···O2^ii	0.86	2.18	2.894 (3)	140
N3—H3···O1^ii	0.86	2.64	3.246 (3)	129
N2—H2···O1^iii	0.86	2.02	2.878 (3)	175

Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) −x+1, −y+1, −z; (iii) x, y−1, z.