Urea–adipic acid (2/1)

Chang, H.-S.; Lin, J.-L.

doi:10.1107/S1600536811015273

organic compounds

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ISSN: 2056-9890

Volume 67| Part 6| June 2011| Page o1317

doi:10.1107/S1600536811015273

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Urea–adipic acid (2/1)

Hai-Sheng Chang ^a and Jian-Li Lin ^a ^*

^aCenter of Applied Solid State Chemistry Research, Ningbo University, Ningbo, Zhejiang 315211, People's Republic of China
^*Correspondence e-mail: linjianli@nbu.edu.cn

(Received 30 March 2011; accepted 22 April 2011; online 7 May 2011)

The asymmetric unit of the title co-crystal, 2CH₄N₂O·C₆H₁₀O₄, contains two urea molecules and two half-molecules of adipic acid; the latter are completed by crystallographic inversion symmetry. The crystal packing is stabilized by O—H⋯O and N—H⋯O hydrogen bonds, generating a chain along [110]. Additional weak inter-chain O—H⋯O and N—H⋯O intermolecular interactions lead to the formation of a three-dimensional network.

Related literature

For urea inclusion compounds, see: Videnova-Adrabińska (1996a ); Harris & Thomas (1990 ); Yeo et al. (1997 ). For urea–dicarboxylic acid co-crystal engineering with predesigned crystal building blocks, see: Videnova-Adrabińska (1996b ). For a urea-dicarboxylic acid co-crystal with a phase diagram, see: Chadwick et al. (2009 ).

Experimental

Crystal data

2CH₄N₂O·C₆H₁₀O₄
M_r = 266.26
Triclinic, $[P \overline 1]$
a = 7.2484 (14) Å
b = 7.6965 (15) Å
c = 11.964 (2) Å
α = 101.81 (3)°
β = 92.55 (3)°
γ = 91.92 (3)°
V = 652.0 (2) Å³
Z = 2
Mo Kα radiation
μ = 0.12 mm⁻¹
T = 293 K
0.35 × 0.26 × 0.18 mm

Data collection

Rigaku R-AXIS RAPID diffractometer
Absorption correction: multi-scan (ABSCOR; Higashi, 1995 ) T_min = 0.965, T_max = 0.980
6479 measured reflections
2949 independent reflections
1457 reflections with I > 2σ(I)
R_int = 0.048

Refinement

R[F² > 2σ(F²)] = 0.049
wR(F²) = 0.186
S = 1.11
2949 reflections
164 parameters
H-atom parameters constrained
Δρ_max = 0.37 e Å⁻³
Δρ_min = −0.35 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2E⋯O6	0.84	1.78	2.611 (3)	173
O4—H4C⋯O5	0.84	1.77	2.588 (3)	167
N1—H1A⋯O5ⁱ	0.86	2.09	2.942 (3)	172
N1—H1B⋯O2ⁱⁱ	0.86	2.42	3.203 (3)	151
N2—H2A⋯O3	0.86	2.20	3.031 (4)	164
N2—H2B⋯O2ⁱⁱ	0.86	2.38	3.171 (4)	154
N3—H3A⋯O1	0.86	2.08	2.912 (4)	163
N3—H3B⋯O4	0.86	2.34	3.049 (3)	140
N4—H4A⋯O6ⁱⁱⁱ	0.86	2.11	2.956 (3)	170
N4—H4B⋯O3^iv	0.86	2.26	3.055 (3)	155
Symmetry codes: (i) -x+1, -y+2, -z+1; (ii) x, y, z-1; (iii) -x, -y+2, -z+2; (iv) -x, -y+1, -z+1.

Data collection: RAPID-AUTO (Rigaku, 1998 ); cell refinement: RAPID-AUTO; data reduction: CrystalStructure (Rigaku/MSC, 2004 ); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811015273/jj2086sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811015273/jj2086Isup2.hkl

checkCIF report

Comment top

There is considerable interest in the structural and dynamic properties of urea inclusion compounds. In these solids (Videnova-Adrabińska, 1996a), the urea molecules form an extensively hydrogen-bonded host structure (Harris et al., 1990), containing linear, parallel tunnels with guest molecules packed densely along these tunnels (Yeo et al., 1997). This crystal structure study is part of a broader program of urea-dicarboxylic acid cocrystal engineering with predesigned crystal building blocks (Videnova-Adrabińska 1996b). The phase diagram of a related urea-dicarboxylic co-crystal has also been reported (Chadwick et al., 2009). In this contribution, we report the title compound with Urea–adipic acid cocrystals (2:1) which form an extensively hydrogen-bonded three-dimensional supramolecular architecture.

The asymmetric unit contains two urea molecules and two half-adipic acid molecules, with the complete adipic acid molecule generated via crystallographic inversion symmetry (Fig. 1). The carboxylic groups of adipic acid connect with the corresponding urea molecules and inter-urea through O4–H4C···O5, N2–H2A···O3 and N1–H1A···O5ⁱⁱⁱ (Table. 1) hydrogen bonds generating a one-dimensional chain along [110] (Fig. 2). Nearby, mutually perpendicular chairs are connected in a similar fashion forming a chain with O2–H2E···O6, N3–H3A···O1 and N4–H4A···O6^v hydrogen bond interactions. Additional weak inter-chain O–H···O and N–H···O intermolecular interactions (Table. 1) support an extensive three-dimensional network, which consolidates the crystal packing (Fig. 3).

Related literature top

For urea inclusion compounds, see: Videnova-Adrabińska (1996a); Harris & Thomas (1990); Yeo et al. (1997). For urea–dicarboxylic acid co-crystal engineering with predesigned crystal building blocks, see: Videnova-Adrabińska (1996b). For a urea-dicarboxylic acid co-crystal with a phase diagram, see: Chadwick et al. (2009).

Experimental top

Adipic acid (0.0371 g, 0.25 mmol) and urea (0.0360 g, 0.60 mmol) were dissolved in 15 ml water (pH = 3.11) under stirring. After slow evaporation of the solution for one week at 50°C, colorless block crystals were formed.

Computing details top

Data collection: RAPID-AUTO (Rigaku, 1998); cell refinement: RAPID-AUTO (Rigaku, 1998); data reduction: CrystalStructure (Rigaku/MSC, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. Molecular structure of the title co-crystal. Displacement ellipsoids are shown at the 45% probability level.(#1 = -x + 2, -y + 1, -z + 2; #2 = -x, -y, -z + 1)
	Fig. 2. One-dimensional chain of the title co-crystal viewed along the b axis. O–H···O and N–H···O hydrogen bonds are shown as dashed lines.
	Fig. 3. Packing diagram of the title co-crystal viewed down the a axis. O–H···O and N–H···O hydrogen bonds are shown as dashed lines.

Urea–adipic acid (2/1) top

Crystal data top

2CH₄N₂O·C₆H₁₀O₄	Z = 2
M_r = 266.26	F(000) = 284
Triclinic, P1	D_x = 1.356 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.2484 (14) Å	Cell parameters from 3579 reflections
b = 7.6965 (15) Å	θ = 3.2–27.5°
c = 11.964 (2) Å	µ = 0.12 mm⁻¹
α = 101.81 (3)°	T = 293 K
β = 92.55 (3)°	Block, colorless
γ = 91.92 (3)°	0.35 × 0.26 × 0.18 mm
V = 652.0 (2) Å³

Data collection top

Rigaku R-AXIS RAPID diffractometer	2949 independent reflections
Radiation source: fine-focus sealed tube	1457 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.048
ω scans	θ_max = 27.5°, θ_min = 3.2°
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	h = −9→8
T_min = 0.965, T_max = 0.980	k = −9→9
6479 measured reflections	l = −15→15

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.049	H-atom parameters constrained
wR(F²) = 0.186	w = 1/[σ²(F_o²) + (0.0647P)² + 0.4241P] where P = (F_o² + 2F_c²)/3
S = 1.11	(Δ/σ)_max < 0.001
2949 reflections	Δρ_max = 0.37 e Å⁻³
164 parameters	Δρ_min = −0.35 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.072 (9)

Crystal data top

2CH₄N₂O·C₆H₁₀O₄	γ = 91.92 (3)°
M_r = 266.26	V = 652.0 (2) Å³
Triclinic, P1	Z = 2
a = 7.2484 (14) Å	Mo Kα radiation
b = 7.6965 (15) Å	µ = 0.12 mm⁻¹
c = 11.964 (2) Å	T = 293 K
α = 101.81 (3)°	0.35 × 0.26 × 0.18 mm
β = 92.55 (3)°

Data collection top

Rigaku R-AXIS RAPID diffractometer	2949 independent reflections
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	1457 reflections with I > 2σ(I)
T_min = 0.965, T_max = 0.980	R_int = 0.048
6479 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.049	0 restraints
wR(F²) = 0.186	H-atom parameters constrained
S = 1.11	Δρ_max = 0.37 e Å⁻³
2949 reflections	Δρ_min = −0.35 e Å⁻³
164 parameters

Special details top

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) top

	x	y	z	U_iso*/U_eq
O1	0.5934 (4)	0.6694 (4)	0.8940 (2)	0.0678 (8)
O2	0.5075 (3)	0.7886 (3)	1.06743 (19)	0.0478 (6)
H2E	0.4187	0.8216	1.0308	0.072*
C1	0.6238 (4)	0.7000 (4)	0.9963 (3)	0.0408 (7)
C2	0.7946 (4)	0.6471 (4)	1.0527 (3)	0.0443 (8)
H2C	0.7600	0.5941	1.1160	0.053*
H2D	0.8716	0.7530	1.0838	0.053*
C3	0.9073 (4)	0.5167 (4)	0.9733 (3)	0.0435 (8)
H3C	0.8368	0.4046	0.9506	0.052*
H3D	0.9276	0.5622	0.9048	0.052*
O3	0.1850 (4)	0.3529 (3)	0.37617 (19)	0.0552 (7)
O4	0.2542 (3)	0.5187 (3)	0.54892 (18)	0.0500 (6)
H4C	0.2980	0.5916	0.5130	0.075*
C4	0.1849 (4)	0.3734 (4)	0.4793 (3)	0.0399 (7)
C5	0.1037 (5)	0.2411 (4)	0.5417 (3)	0.0438 (8)
H5A	0.0037	0.2953	0.5857	0.053*
H5B	0.1977	0.2146	0.5952	0.053*
C6	0.0300 (4)	0.0679 (4)	0.4655 (3)	0.0422 (8)
H6A	0.1253	0.0190	0.4153	0.051*
H6B	−0.0745	0.0914	0.4182	0.051*
O5	0.3998 (3)	0.7766 (3)	0.46884 (18)	0.0477 (6)
C7	0.4225 (4)	0.7824 (4)	0.3659 (3)	0.0404 (7)
N1	0.4904 (4)	0.9306 (3)	0.3376 (2)	0.0522 (8)
H1A	0.5191	1.0232	0.3900	0.063*
H1B	0.5054	0.9332	0.2671	0.063*
N2	0.3789 (5)	0.6436 (4)	0.2825 (2)	0.0600 (9)
H2A	0.3341	0.5469	0.2982	0.072*
H2B	0.3953	0.6499	0.2127	0.072*
O6	0.2201 (3)	0.9024 (3)	0.96911 (17)	0.0419 (6)
C8	0.1495 (4)	0.8482 (4)	0.8697 (3)	0.0370 (7)
N3	0.2432 (4)	0.7456 (4)	0.7892 (2)	0.0564 (8)
H3A	0.3532	0.7161	0.8053	0.068*
H3B	0.1935	0.7093	0.7215	0.068*
N4	−0.0194 (4)	0.8939 (3)	0.8407 (2)	0.0466 (7)
H4A	−0.0815	0.9615	0.8904	0.056*
H4B	−0.0660	0.8558	0.7723	0.056*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0634 (17)	0.0839 (18)	0.0446 (16)	0.0303 (14)	−0.0110 (13)	−0.0150 (13)
O2	0.0428 (13)	0.0601 (14)	0.0419 (13)	0.0105 (11)	0.0071 (10)	0.0118 (11)
C1	0.0391 (18)	0.0333 (15)	0.048 (2)	0.0012 (13)	0.0018 (15)	0.0027 (14)
C2	0.0412 (18)	0.0391 (16)	0.052 (2)	0.0007 (14)	−0.0008 (15)	0.0094 (15)
C3	0.0404 (18)	0.0329 (15)	0.055 (2)	−0.0023 (13)	−0.0013 (15)	0.0056 (14)
O3	0.0784 (18)	0.0461 (13)	0.0371 (14)	−0.0182 (12)	0.0011 (12)	0.0028 (10)
O4	0.0681 (16)	0.0402 (12)	0.0383 (13)	−0.0146 (11)	0.0061 (11)	0.0023 (10)
C4	0.0424 (18)	0.0352 (15)	0.0406 (19)	−0.0028 (13)	0.0007 (14)	0.0056 (13)
C5	0.0489 (19)	0.0397 (16)	0.0441 (19)	−0.0006 (14)	0.0061 (15)	0.0117 (14)
C6	0.0426 (18)	0.0365 (15)	0.0493 (19)	−0.0005 (13)	0.0053 (15)	0.0124 (14)
O5	0.0645 (16)	0.0396 (12)	0.0363 (13)	−0.0118 (11)	0.0069 (11)	0.0023 (9)
C7	0.0412 (18)	0.0370 (16)	0.0407 (18)	−0.0024 (13)	0.0043 (14)	0.0028 (13)
N1	0.074 (2)	0.0440 (15)	0.0369 (15)	−0.0141 (14)	0.0108 (14)	0.0057 (12)
N2	0.090 (2)	0.0472 (16)	0.0367 (16)	−0.0175 (16)	0.0021 (15)	−0.0016 (13)
O6	0.0444 (13)	0.0450 (12)	0.0329 (12)	0.0059 (10)	−0.0015 (10)	0.0004 (9)
C8	0.0424 (18)	0.0330 (15)	0.0346 (17)	0.0004 (13)	0.0029 (14)	0.0049 (13)
N3	0.063 (2)	0.0648 (18)	0.0359 (16)	0.0191 (16)	0.0028 (14)	−0.0042 (13)
N4	0.0459 (17)	0.0509 (15)	0.0399 (15)	0.0055 (13)	−0.0052 (12)	0.0032 (12)

Geometric parameters (Å, º) top

O1—C1	1.207 (4)	C6—C6ⁱⁱ	1.522 (6)
O2—C1	1.329 (4)	C6—H6A	0.9700
O2—H2E	0.8383	C6—H6B	0.9700
C1—C2	1.492 (4)	O5—C7	1.259 (4)
C2—C3	1.520 (4)	C7—N2	1.323 (4)
C2—H2C	0.9700	C7—N1	1.339 (4)
C2—H2D	0.9700	N1—H1A	0.8600
C3—C3ⁱ	1.515 (6)	N1—H1B	0.8600
C3—H3C	0.9700	N2—H2A	0.8600
C3—H3D	0.9700	N2—H2B	0.8600
O3—C4	1.212 (4)	O6—C8	1.257 (3)
O4—C4	1.319 (4)	C8—N4	1.335 (4)
O4—H4C	0.8357	C8—N3	1.340 (4)
C4—C5	1.500 (4)	N3—H3A	0.8600
C5—C6	1.518 (4)	N3—H3B	0.8600
C5—H5A	0.9700	N4—H4A	0.8600
C5—H5B	0.9700	N4—H4B	0.8600

C1—O2—H2E	110.5	H5A—C5—H5B	107.5
O1—C1—O2	121.8 (3)	C5—C6—C6ⁱⁱ	112.1 (3)
O1—C1—C2	123.4 (3)	C5—C6—H6A	109.2
O2—C1—C2	114.8 (3)	C6ⁱⁱ—C6—H6A	109.2
C1—C2—C3	113.9 (3)	C5—C6—H6B	109.2
C1—C2—H2C	108.8	C6ⁱⁱ—C6—H6B	109.2
C3—C2—H2C	108.8	H6A—C6—H6B	107.9
C1—C2—H2D	108.8	O5—C7—N2	121.3 (3)
C3—C2—H2D	108.8	O5—C7—N1	120.7 (3)
H2C—C2—H2D	107.7	N2—C7—N1	118.0 (3)
C3ⁱ—C3—C2	113.4 (3)	C7—N1—H1A	120.0
C3ⁱ—C3—H3C	108.9	C7—N1—H1B	120.0
C2—C3—H3C	108.9	H1A—N1—H1B	120.0
C3ⁱ—C3—H3D	108.9	C7—N2—H2A	120.0
C2—C3—H3D	108.9	C7—N2—H2B	120.0
H3C—C3—H3D	107.7	H2A—N2—H2B	120.0
C4—O4—H4C	111.7	O6—C8—N4	121.0 (3)
O3—C4—O4	122.7 (3)	O6—C8—N3	120.8 (3)
O3—C4—C5	124.5 (3)	N4—C8—N3	118.1 (3)
O4—C4—C5	112.8 (3)	C8—N3—H3A	120.0
C4—C5—C6	114.8 (3)	C8—N3—H3B	120.0
C4—C5—H5A	108.6	H3A—N3—H3B	120.0
C6—C5—H5A	108.6	C8—N4—H4A	120.0
C4—C5—H5B	108.6	C8—N4—H4B	120.0
C6—C5—H5B	108.6	H4A—N4—H4B	120.0

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2E···O6	0.84	1.78	2.611 (3)	173
O4—H4C···O5	0.84	1.77	2.588 (3)	167
N1—H1A···O5ⁱⁱⁱ	0.86	2.09	2.942 (3)	172
N1—H1B···O2^iv	0.86	2.42	3.203 (3)	151
N2—H2A···O3	0.86	2.20	3.031 (4)	164
N2—H2B···O2^iv	0.86	2.38	3.171 (4)	154
N3—H3A···O1	0.86	2.08	2.912 (4)	163
N3—H3B···O4	0.86	2.34	3.049 (3)	140
N4—H4A···O6^v	0.86	2.11	2.956 (3)	170
N4—H4B···O3^vi	0.86	2.26	3.055 (3)	155

Symmetry codes: (iii) −x+1, −y+2, −z+1; (iv) x, y, z−1; (v) −x, −y+2, −z+2; (vi) −x, −y+1, −z+1.

Experimental details

Crystal data
Chemical formula	2CH₄N₂O·C₆H₁₀O₄
M_r	266.26
Crystal system, space group	Triclinic, P1
Temperature (K)	293
a, b, c (Å)	7.2484 (14), 7.6965 (15), 11.964 (2)
α, β, γ (°)	101.81 (3), 92.55 (3), 91.92 (3)
V (Å³)	652.0 (2)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.12
Crystal size (mm)	0.35 × 0.26 × 0.18

Data collection
Diffractometer	Rigaku R-AXIS RAPID diffractometer
Absorption correction	Multi-scan (ABSCOR; Higashi, 1995)
T_min, T_max	0.965, 0.980
No. of measured, independent and observed [I > 2σ(I)] reflections	6479, 2949, 1457
R_int	0.048
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.049, 0.186, 1.11
No. of reflections	2949
No. of parameters	164
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.37, −0.35

Computer programs: RAPID-AUTO (Rigaku, 1998), CrystalStructure (Rigaku/MSC, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2E···O6	0.84	1.78	2.611 (3)	173
O4—H4C···O5	0.84	1.77	2.588 (3)	167
N1—H1A···O5ⁱ	0.86	2.09	2.942 (3)	172
N1—H1B···O2ⁱⁱ	0.86	2.42	3.203 (3)	151
N2—H2A···O3	0.86	2.20	3.031 (4)	164
N2—H2B···O2ⁱⁱ	0.86	2.38	3.171 (4)	154
N3—H3A···O1	0.86	2.08	2.912 (4)	163
N3—H3B···O4	0.86	2.34	3.049 (3)	140
N4—H4A···O6ⁱⁱⁱ	0.86	2.11	2.956 (3)	170
N4—H4B···O3^iv	0.86	2.26	3.055 (3)	155

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

Acknowledgements

This project was supported by the Scientific Research Fund of Ningbo University (grant No. XKL069). Thanks are also extended to the K. C. Wong Magna Fund in Ningbo University.

References

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