organic papers
Acta Cryst.(2005). E61, o3269–o3270 doi:10.1107/S1600536805028023 Caudleet al. C
4H8N2O
o3269
Acta Crystallographica Section E Structure Reports
Online
ISSN 1600-5368
Anhydrous 1-methylimidazolidin-2-one
M. Tyler Caudle,* Erica Tassone and Thomas L. Groy
Department of Chemistry and Biochemistry, Arizona State University, Box 871604, Tempe, AZ 85287-1604, USA
Correspondence e-mail: tcaudle@asu.edu
Key indicators
Single-crystal X-ray study
T= 298 K
Mean(C–C) = 0.004 A˚
Rfactor = 0.070
wRfactor = 0.161
Data-to-parameter ratio = 13.7
For details of how these key indicators were automatically derived from the article, see http://journals.iucr.org/e.
#2005 International Union of Crystallography Printed in Great Britain – all rights reserved
The title compound, C4H8N2O, crystallizes from the vapor
phase in sheets supported by a one-dimensional hydrogen-bonded network. The molecular unit shows planar ureido
—NCH3 groups, but the slight out-of-plane hydrogen-bond
geometry may be indicative of some pyramidalization of the ureido —NH groups.
Comment
The imidazolidin-2-one functional group is of primary importance in the transfer of carbon dioxide by biotin-dependent enzymes (Carey et al., 2004; Attwood & Wallace, 2002). It is therefore important that the structural character-istics of this unit be well understood. In the course of our work on biomimetic carbon dioxide fixation, we crystallized anhy-drous 1-methylimidazolidin-2-one, (I), and report here its crystal structure.
The molecular unit in (I) shows the five-membered heterocycle. The ring is only slightly enveloped, with an average internal torsion angle of 4.6 and a mean deviation
from planarity of 0.0273 A˚ . The metrical parameters in the heterocycle are essentially identical to those in unsubstituted imidazolidin-2-one (Kapon & Reisner, 1989), and to those in biotin itself (DeTitta et al., 1976). Methylated atom N2 is planar, indicative of largely sp2-hybrid character. This is
consistent withN-silyl-substituted imidazolidin-2-ones (Szalay
et al., 2005), as well as withN10-methoxycarbonylbiotin methyl
[image:1.610.259.411.596.730.2]Received 11 August 2005 Accepted 6 September 2005 Online 17 September 2005
Figure 1
planar ureido N atoms. However, the planar N atoms are at variance with some theoretical work which seems to indicate that the N atoms in urea and related molecules have consid-erablesp3character (Meier & Coussens, 1992). Some insight may be gained from the solid state packing in (I), which is supported by a one-dimensional network of hydrogen bonds (O N = 2.87 A˚ ). Neighboring hydrogen-bonded chains are packed to form a two-dimensional sheet (Fig. 2). The individual hydrogen-bonding interactions are inclined at 19.8
to the heterocycle plane, and may be indicative of some pyramidalization of the —NH group.
Experimental
The title compound was purchased from Aldrich. The microcrystal-line powder was placed in a flame-sealed ampoule and the apparatus stored in a 363 K oven for one week. This procedure gave colorless blocks suitable for X-ray diffraction.
Crystal data
C4H8N2O Mr= 100.12 Monoclinic,P21=c a= 7.5746 (11) A˚ b= 9.3984 (13) A˚ c= 7.9482 (11) A˚
= 117.139 (2) V= 503.53 (12) A˚3 Z= 4
Dx= 1.321 Mg m 3
MoKradiation Cell parameters from 1593
reflections
= 3.0–31.6
= 0.10 mm1 T= 298 (2) K Block, colorless 0.380.300.10 mm
Data collection
Bruker SMART APEX diffractometer
!scans
Absorption correction: scan (Blessing, 1995)
Tmin= 0.94,Tmax= 0.99
3853 measured reflections
888 independent reflections 712 reflections withI> 2(I) Rint= 0.092
max= 25.0 h=9!9 k=11!11 l=9!9
Refinement
Refinement onF2 R[F2> 2(F2)] = 0.070 wR(F2) = 0.161 S= 1.16 888 reflections 65 parameters
H-atom parameters constrained
w= 1/[2(F
o2) + (0.0535P)2
+ 0.1874P]
whereP= (Fo2+ 2Fc2)/3
(/)max< 0.001
max= 0.14 e A˚
3
min=0.18 e A˚
3
H atoms were placed in idealized positions as riding atoms with C—H distances of 0.96 A˚ for methyl and 0.96 A˚ for the rest; The N— H distance is 0.86 A˚ . The isotropic displacement parameters were set at 1.5Ueqof the parent atom for the methyl H atoms and 1.2Ueqfor
the rest.
Data collection:SMART(Bruker, 1997); cell refinement: SAINT-Plus(Bruker, 1997); data reduction:SAINT-Plus; program(s) used to solve structure: SHELXS97(Sheldrick, 1997); program(s) used to refine structure:SHELXL97(Sheldrick, 1997); molecular graphics:
SHELXTL (Bruker 1997); software used to prepare material for publication:SHELXTL.
References
Attwood, P. V. & Wallace, J. C. (2002).Acc. Chem. Res.35, 113–120. Blessing, R. H. (1995).Acta Cryst.A51, 33–38.
Bruker (1997).SMART(Version 5.625), SAINT-Plus (Version 6.28a) and SHELXTL(Version 5.1). Bruker AXS Inc., Madison, Wisconsin, USA. Carey, P., Soennichsen, F. & Yee, V. (2004).IUBMB Life,56, 575–583. DeTitta, G. T., Edmonds, J. W., Stallings, W. & Donohue, J. (1976).J. Am.
Chem. Soc.98, 1920–1926.
Kapon, M. & Reisner, G. M. (1989).Acta Cryst.C45, 780–782.
Meier, R. J. & Coussens, B. (1992).J. Mol. Struct. (Theochem),253, 25–33. Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of
Go¨ttingen, Germany.
Stallings, W. C., Monti, C. T., Lane, M. D. & DeTitta, G. T. (1980).Proc. Natl Acad. Sci. USA,77, 1260–1264.
[image:2.610.315.564.70.315.2]Szalay, R., Pongor, G., Harmat, V., Boecskei, Z. & Knausz, D. (2005). J. Organomet. Chem.690, 1498–1506.
Figure 2
Solid-state packing diagram of (I), viewed down the crystallographica
supporting information
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Acta Cryst. (2005). E61, o3269–o3270supporting information
Acta Cryst. (2005). E61, o3269–o3270 [doi:10.1107/S1600536805028023]
Anhydrous 1-methylimidazolidin-2-one
M. Tyler Caudle, Erica Tassone and Thomas L. Groy
S1. Comment
The imidazolidin-2-one functional group is of primary importance in the transfer of carbon dioxide by biotin-dependent
enzymes (Carey et al., 2004; Attwood & Wallace, 2002). It is therefore important that the structural characteristics of this
unit be well understood. In the course of our work on biomimetic carbon dioxide fixation, we crystallized anhydrous N
-methylimidazolidin-2-one, (I), and report here its crystal structure.
The molecular unit in (I) shows the five-membered heterocycle. The ring is only slightly enveloped, with an average
internal torsion angle of 4.6° and a mean deviation from planarity of 0.0273 Å. The metrical parameters in the
heterocycle are essentially identical to those in unsubstituted imidazolidin-2-one (Kapon & Reisner, 1989), and to those
in biotin itself (DeTitta et al., 1976). Methylated atom N2 is planar, indicative of largely sp2-hybrid character. This is
consistent with N-silyl-substituted imidazolidin-2-ones (Szalay et al., 2005), as well as with N1′-methoxycarbonylbiotin
methyl ester (Stallings et al., 1980), which also exhibit essentially planar ureido N atoms. However, the planar N atoms
are at variance with some theoretical work which seems to indicate that the N atoms in urea and related molecules have
considerable sp3 character·(Meier & Coussens, 1992). Some insight may be gained from the solid state packing in (I),
which is supported by a one-dimensional network of hydrogen bonds (O···N = 2.87 Å). Neighboring hydrogen-bonded
chains are packed to form a two-dimensional sheet (Fig. 2). The individual hydrogen-bonding interactions are 19.8° out
of the heterocycle plane, and may be indicative of some pyramidalization of the —NH group.
S2. Experimental
The title compopund was purchased from Aldrich. The microcrystalline powder was placed in a flame-sealed ampoule
and the apparatus stored in a 363 K oven for one week. This procedure gave colorless blocks suitable for X-ray
diffraction.
S3. Refinement
H atoms were added in idealized positions as riding atoms with C—H distances of 0.96 Å for methyl and 0.96 Å for the
rest; The N—H distance is 0.86 Å. The isotropic displacement parameters were set at 1.5Ueq of the parent atom for the
Figure 1
supporting information
[image:5.610.127.482.71.416.2]sup-3
Acta Cryst. (2005). E61, o3269–o3270Figure 2
Solid-state packing diagram of (I), viewed down the crystallographic a axis.
N-methylimidazolidin-2-one
Crystal data
C4H8N2O Mr = 100.12
Monoclinic, P21/c Hall symbol: -P 2ybc
a = 7.5746 (11) Å
b = 9.3984 (13) Å
c = 7.9482 (11) Å
β = 117.139 (2)°
V = 503.53 (12) Å3 Z = 4
F(000) = 216
Dx = 1.321 Mg m−3
Mo Kα radiation, λ = 0.71073 Å Cell parameters from 1593 reflections
θ = 3.0–31.6°
µ = 0.10 mm−1 T = 298 K Block, colorless 0.38 × 0.30 × 0.10 mm
Data collection
Bruker SMART APEX diffractometer
Radiation source: fine-focus sealed tube Graphite monochromator
ω scans
Absorption correction: ψ scan (Blessing, 1995)
θmax = 25.0°, θmin = 3.0° h = −9→9
l = −9→9
Refinement
Refinement on F2 Least-squares matrix: full
R[F2 > 2σ(F2)] = 0.070 wR(F2) = 0.161 S = 1.16 888 reflections 65 parameters 0 restraints
Primary atom site location: structure-invariant direct methods
Secondary atom site location: difference Fourier map
Hydrogen site location: inferred from neighbouring sites
H-atom parameters constrained
w = 1/[σ2(F
o2) + (0.0535P)2 + 0.1874P] where P = (Fo2 + 2Fc2)/3
(Δ/σ)max < 0.001 Δρmax = 0.14 e Å−3 Δρmin = −0.18 e Å−3
Special details
Experimental. Add this here
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)
x y z Uiso*/Ueq
O1 0.7224 (3) 1.23376 (17) −0.0327 (3) 0.0607 (7) C1 0.7478 (4) 1.1137 (3) 0.0358 (4) 0.0422 (7) N2 0.7386 (4) 0.9918 (2) −0.0542 (3) 0.0570 (8) C2 0.6997 (5) 0.9812 (3) −0.2483 (4) 0.0610 (9) H2A 0.6795 1.0746 −0.3028 0.092* H2B 0.5829 0.9247 −0.3170 0.092* H2C 0.8107 0.9371 −0.2550 0.092* C3 0.7750 (4) 0.8699 (3) 0.0645 (4) 0.0565 (8) H3A 0.8956 0.8215 0.0827 0.068* H3B 0.6650 0.8035 0.0114 0.068* C4 0.7961 (4) 0.9324 (3) 0.2486 (4) 0.0556 (8) H4A 0.6873 0.9032 0.2734 0.067* H4B 0.9206 0.9043 0.3541 0.067* N5 0.7908 (4) 1.0826 (2) 0.2151 (3) 0.0601 (8) H5A 0.8129 1.1459 0.3007 0.072*
Atomic displacement parameters (Å2)
U11 U22 U33 U12 U13 U23
supporting information
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Acta Cryst. (2005). E61, o3269–o3270N2 0.090 (2) 0.0353 (12) 0.0456 (14) 0.0022 (11) 0.0304 (14) −0.0031 (9) C2 0.079 (2) 0.0567 (19) 0.0485 (18) −0.0074 (15) 0.0303 (17) −0.0119 (13) C3 0.067 (2) 0.0361 (15) 0.067 (2) 0.0078 (13) 0.0305 (17) 0.0036 (12) C4 0.065 (2) 0.0481 (16) 0.0527 (17) 0.0075 (14) 0.0256 (15) 0.0124 (13) N5 0.101 (2) 0.0390 (13) 0.0485 (14) 0.0025 (12) 0.0414 (14) −0.0005 (10)
Geometric parameters (Å, º)
O1—C1 1.229 (3) C3—C4 1.516 (4)
C1—N2 1.336 (3) C3—H3A 0.9700
C1—N5 1.341 (3) C3—H3B 0.9700
N2—C3 1.429 (3) C4—N5 1.434 (4)
N2—C2 1.436 (3) C4—H4A 0.9700
C2—H2A 0.9600 C4—H4B 0.9700
C2—H2B 0.9600 N5—H5A 0.8600
C2—H2C 0.9600
O1—C1—N2 126.2 (2) C4—C3—H3A 111.1 O1—C1—N5 125.7 (2) N2—C3—H3B 111.1 N2—C1—N5 108.1 (2) C4—C3—H3B 111.1 C1—N2—C3 112.7 (2) H3A—C3—H3B 109.1 C1—N2—C2 124.8 (2) N5—C4—C3 102.7 (2) C3—N2—C2 122.5 (2) N5—C4—H4A 111.2 N2—C2—H2A 109.5 C3—C4—H4A 111.2 N2—C2—H2B 109.5 N5—C4—H4B 111.2 H2A—C2—H2B 109.5 C3—C4—H4B 111.2 N2—C2—H2C 109.5 H4A—C4—H4B 109.1 H2A—C2—H2C 109.5 C1—N5—C4 112.6 (2) H2B—C2—H2C 109.5 C1—N5—H5A 123.7 N2—C3—C4 103.3 (2) C4—N5—H5A 123.7 N2—C3—H3A 111.1