8-Quinolinyl­urea

The crystal structure of 8-quinolinyl­urea, C₁₀H₉N₃O, shows the urea moiety to be close to coplanar with the quinoline ring, due to intramolecular hydrogen bonding between the quinoline-N atom and the H atom on the nearest urea N, and between the urea O atom and a quinoline-ring H atom. The mol­ecules associate, through hydrogen bonds involving all potential donor and acceptor sites, to form a two-dimensional sheet structure.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.044
• wR factor = 0.098
• Data-to-parameter ratio = 11.2

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

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S1. Comment

We have previously reported the synthesis and crystal structures of unsymmetrically substituted ureas together with their adducts with a number of carboxylic acids. These ureas included phenylurea (Kashino & Haisa, 1977; Bott et al., 2000) and 1,1-diethylurea (Smith & Kennard, 2000; Smith et al., 2000). These unsymmetrically substituted ureas are of interest because of their potential herbicidal properties, e.g. monuron [3-(4-chlorophenyl)-1,1-dimethylurea; Baughman, Hembre et al., 1980] and diuron [3-(3,4-dichlorophenyl) 1,1-dimethylurea; Baughman, Sams et al., 1980] are commercial herbicides. The structure of the 1:1 proton-transfer compound of the unsymmetrical Lewis base-substituted urea (8-quinolinyl)urea with 3,5-dinitrosalicylic acid has previously been reported (Smith et al., 2001) and we report here the crystal structure of the parent urea compound, (8-quinolinyl)urea, (I), which has also been investigated for its phytotoxic properties (Pagani et al., 1983; Smith et al., 1997). This determination shows only minor deviations from planarity in the overall molecule (Fig. 1) with the torsion angles C7–C8–N11–C21 and C8–N11–C21–N31 being 8.6 (3) and 171.0 (1) Å, respectively. This is largely due to the presence of intramolecular hydrogen bonds, on one side between the proton on the first urea-N atom and the hetero-N atom of the quinoline residue [N11···N1 = 2.685 (2) Å], and on the other side between the urea O atom and a quinoline ring H atom [O21···C7 = 2.895 (2) Å]. The (8-quinolinium)urea cations in the 1:1 proton-transfer compound with 3,5-dinitrosalicylic acid are considerably different conformationally, with the urea side chain inverted and non-coplanar with the quinoline ring and with no intramolecular hydrogen bonds. The molecules of (I) also give a cyclic hydrogen-bonding association through the urea functional groups and the hetero-N atom of the quinoline ring (Fig. 2 and Table 1). These dimers then are then extended into a convoluted two-dimensional sheet structure via similar peripheral n-glide-related molecules with a separation of ca 3.8 Å [Cg1···Cg1 = 3.838 (3) Å and α = 2.89 (2)°] between the sheets.

S2. Experimental

The title compound, (I), was synthesized using the Vogel (1989) procedure. 8-Aminoquinoline (10 g, 0,069 mmol) was dissolved in 10 ml of hot glacial acetic acid and a solution of NaCNO (4.51 g, 0.069 mmol) in 50 ml of warm water was added with stirring, and the warmed solution stirred for a further 30 min. The mixture was cooled on an ice bath for 30 min and the precipitate of (I) removed by vacuum filtration and vacuum dried, giving 10 g of off-white product (77% yield). Recrystallization from absolute ethanol gave colourless data crystals (m.p. 476–477 K) suitable for X-ray diffraction.

S3. Refinement

H atoms involved in hydrogen-bonding inetractions (H11, H31A and H31B) were located by difference syntheses and their positional and isotropic displacement parameters were refined. Other H atoms were included in the refinement in the riding-model approximation.

Computing details

Data collection: SMART (Bruker, 2000); cell refinement: SMART; data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXTL97 (Bruker, 1997); program(s) used to refine structure: SHELXTL97; molecular graphics: PLATON for Windows (Spek, 1999); software used to prepare material for publication: SHELXTL97.

Figures

	Fig. 1. The molecular configuration and atom-naming scheme for (I), with atoms drawn as 30% probability ellipsoids.
	Fig. 2. Packing in the unit cell, viewed down a, showing hydrogen-bonding interactions as broken lines,

8-quinolinylurea

Crystal data

C10H9N3O	F(000) = 392
Mr = 187.20	Dx = 1.402 Mg m^−3
Monoclinic, P21/n	Melting point = 476–477 K
Hall symbol: -P 2y n	Mo Kα radiation, λ = 0.71073 Å
a = 7.1436 (8) Å	Cell parameters from 978 reflections
b = 8.1394 (9) Å	θ = 2.7–22.1°
c = 15.2836 (17) Å	µ = 0.10 mm^−1
β = 93.333 (2)°	T = 293 K
V = 887.16 (17) Å^3	Block, colourless
Z = 4	0.32 × 0.16 × 0.10 mm

Data collection

Bruker CCD area-detector diffractometer	1133 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.050
Graphite monochromator	θmax = 25.0°, θmin = 2.7°
ϕ and ω scans	h = −8→6
4542 measured reflections	k = −9→9
1566 independent reflections	l = −15→18

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.044	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.098	w = 1/[σ^2(Fo^2) + (0.0391P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 0.97	(Δ/σ)max < 0.001
1566 reflections	Δρmax = 0.13 e Å^−3
140 parameters	Δρmin = −0.12 e Å^−3
0 restraints	Extinction correction: SHELXTL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0062 (18)

Special details

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All e.s.d.'s are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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
O21	0.3942 (2)	0.85917 (16)	0.19967 (8)	0.0791 (6)
N1	0.2027 (2)	0.35554 (16)	0.03980 (9)	0.0479 (5)
N11	0.3135 (2)	0.6068 (2)	0.14424 (10)	0.0530 (6)
N31	0.3128 (3)	0.6553 (3)	0.29036 (12)	0.0873 (9)
C2	0.1491 (3)	0.2315 (2)	−0.01131 (12)	0.0554 (7)
C3	0.1322 (3)	0.2386 (2)	−0.10303 (12)	0.0620 (8)
C4	0.1725 (3)	0.3823 (2)	−0.14244 (12)	0.0603 (8)
C5	0.2810 (3)	0.6708 (2)	−0.12906 (12)	0.0633 (8)
C6	0.3394 (3)	0.7968 (2)	−0.07680 (13)	0.0657 (8)
C7	0.3541 (3)	0.7802 (2)	0.01482 (13)	0.0582 (7)
C8	0.3079 (2)	0.6349 (2)	0.05384 (11)	0.0465 (6)
C9	0.2336 (2)	0.5182 (2)	−0.09216 (11)	0.0497 (7)
C10	0.2471 (2)	0.4995 (2)	−0.00024 (11)	0.0430 (6)
C21	0.3420 (3)	0.7169 (2)	0.21112 (13)	0.0601 (8)
H2	0.120500	0.132600	0.015400	0.0660*
H3	0.094300	0.147100	−0.135900	0.0740*
H4	0.159600	0.390900	−0.203200	0.0720*
H5	0.272000	0.684600	−0.189600	0.0760*
H6	0.370400	0.896400	−0.102000	0.0790*
H7	0.395600	0.868400	0.049400	0.0700*
H11	0.276 (3)	0.510 (2)	0.1571 (11)	0.065 (6)*
H31A	0.256 (3)	0.557 (3)	0.2977 (14)	0.108 (9)*
H31B	0.323 (3)	0.725 (2)	0.3359 (14)	0.092 (7)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O21	0.1126 (13)	0.0523 (9)	0.0718 (10)	−0.0103 (8)	0.0004 (8)	−0.0133 (7)
N1	0.0531 (10)	0.0437 (8)	0.0469 (9)	0.0044 (7)	0.0030 (7)	−0.0024 (7)
N11	0.0683 (12)	0.0444 (10)	0.0461 (10)	−0.0008 (8)	0.0005 (7)	−0.0059 (8)
N31	0.144 (2)	0.0723 (14)	0.0451 (12)	−0.0189 (14)	0.0019 (11)	−0.0138 (11)
C2	0.0618 (13)	0.0473 (11)	0.0572 (12)	0.0006 (9)	0.0039 (9)	−0.0041 (9)
C3	0.0723 (15)	0.0595 (13)	0.0537 (12)	0.0031 (10)	0.0003 (10)	−0.0154 (10)
C4	0.0709 (15)	0.0692 (14)	0.0409 (11)	0.0097 (11)	0.0029 (9)	−0.0059 (10)
C5	0.0754 (15)	0.0669 (13)	0.0484 (11)	0.0059 (11)	0.0115 (10)	0.0110 (10)
C6	0.0758 (15)	0.0568 (12)	0.0656 (14)	−0.0006 (11)	0.0148 (11)	0.0131 (11)
C7	0.0595 (13)	0.0489 (11)	0.0666 (13)	−0.0031 (9)	0.0063 (10)	−0.0028 (9)
C8	0.0431 (11)	0.0491 (11)	0.0473 (11)	0.0059 (8)	0.0031 (8)	−0.0026 (8)
C9	0.0512 (12)	0.0549 (11)	0.0434 (11)	0.0106 (9)	0.0074 (8)	0.0002 (9)
C10	0.0409 (11)	0.0448 (10)	0.0438 (10)	0.0091 (8)	0.0061 (7)	0.0005 (8)
C21	0.0699 (15)	0.0548 (12)	0.0546 (13)	0.0027 (10)	−0.0052 (10)	−0.0106 (10)

Geometric parameters (Å, º)

O21—C21	1.232 (2)	C5—C9	1.413 (2)
N1—C2	1.320 (2)	C5—C6	1.351 (3)
N1—C10	1.368 (2)	C6—C7	1.405 (3)
N11—C8	1.399 (2)	C7—C8	1.373 (2)
N11—C21	1.366 (2)	C8—C10	1.430 (2)
N31—C21	1.338 (3)	C9—C10	1.411 (2)
N11—H11	0.859 (17)	C2—H2	0.9306
N31—H31A	0.91 (2)	C3—H3	0.9298
N31—H31B	0.90 (2)	C4—H4	0.9305
C2—C3	1.401 (3)	C5—H5	0.9306
C3—C4	1.354 (2)	C6—H6	0.9298
C4—C9	1.402 (2)	C7—H7	0.9297
C2—N1—C10	117.22 (14)	N1—C10—C8	118.18 (15)
C8—N11—C21	128.79 (16)	N1—C10—C9	122.26 (15)
C8—N11—H11	112.6 (11)	C8—C10—C9	119.56 (15)
C21—N11—H11	117.8 (11)	O21—C21—N31	123.03 (19)
C21—N31—H31A	122.5 (14)	N11—C21—N31	114.03 (17)
H31A—N31—H31B	118.6 (19)	O21—C21—N11	122.93 (18)
C21—N31—H31B	117.1 (12)	N1—C2—H2	117.75
N1—C2—C3	124.46 (16)	C3—C2—H2	117.79
C2—C3—C4	118.19 (16)	C2—C3—H3	120.86
C3—C4—C9	120.34 (17)	C4—C3—H3	120.95
C6—C5—C9	120.27 (17)	C3—C4—H4	119.84
C5—C6—C7	121.27 (16)	C9—C4—H4	119.82
C6—C7—C8	120.65 (16)	C6—C5—H5	119.82
C7—C8—C10	119.03 (16)	C9—C5—H5	119.90
N11—C8—C10	115.80 (15)	C5—C6—H6	119.33
N11—C8—C7	125.17 (16)	C7—C6—H6	119.41
C4—C9—C10	117.50 (15)	C6—C7—H7	119.69
C4—C9—C5	123.29 (16)	C8—C7—H7	119.66
C5—C9—C10	119.21 (15)
C10—N1—C2—C3	−1.0 (3)	C9—C5—C6—C7	−0.2 (3)
C2—N1—C10—C8	−179.20 (16)	C5—C6—C7—C8	−0.5 (3)
C2—N1—C10—C9	1.2 (2)	C6—C7—C8—N11	−178.49 (17)
C21—N11—C8—C7	8.6 (3)	C6—C7—C8—C10	0.9 (3)
C21—N11—C8—C10	−170.82 (17)	C7—C8—C10—N1	179.64 (15)
C8—N11—C21—O21	−10.6 (3)	C7—C8—C10—C9	−0.8 (2)
C8—N11—C21—N31	170.96 (17)	N11—C8—C10—N1	−0.9 (2)
N1—C2—C3—C4	−0.3 (3)	N11—C8—C10—C9	178.71 (13)
C2—C3—C4—C9	1.5 (3)	C4—C9—C10—N1	−0.1 (2)
C3—C4—C9—C5	178.91 (19)	C5—C9—C10—C8	0.1 (3)
C3—C4—C9—C10	−1.3 (3)	C4—C9—C10—C8	−179.70 (15)
C6—C5—C9—C4	−179.84 (19)	C5—C9—C10—N1	179.72 (15)
C6—C5—C9—C10	0.3 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N11—H11···N1	0.859 (17)	2.227 (17)	2.685 (2)	113.3 (14)
N31—H31A···O21^i	0.91 (2)	1.94 (2)	2.836 (3)	171 (2)
N31—H31B···N1^ii	0.90 (2)	2.19 (2)	3.072 (2)	166.1 (18)
C7—H7···O21	0.93	2.30	2.895 (2)	122

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