1-Benzyl­uracil

In the title compound, C₁₁H₁₀N₂O₂, the benzene ring is almost perpendicular to the heterocycle; the dihedral angle is 91.2 (2)°. A chain structure is formed via an intermolecular N—H...O hydrogen bond.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.007 Å
• R factor = 0.054
• wR factor = 0.126
• Data-to-parameter ratio = 6.8

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT089_ALERT_3_C Poor Data / Parameter Ratio (Zmax .LT. 18) .....       6.75
PLAT230_ALERT_2_C Hirshfeld Test Diff for    O2     -   C9      ..       5.79 su
PLAT340_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          7

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           25.19
           From the CIF: _reflns_number_total                945
           Count of symmetry unique reflns          950
           Completeness (_total/calc)             99.47%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present           no

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

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Bruker, 2002); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

1-Benzyluracil

Crystal data

C11H10N2O2	F(000) = 212
Mr = 202.21	Dx = 1.385 Mg m^−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 578 reflections
a = 6.5304 (4) Å	θ = 2.5–23.5°
b = 6.9483 (3) Å	µ = 0.10 mm^−1
c = 10.9214 (6) Å	T = 298 K
β = 101.934 (2)°	Block, colourless
V = 484.85 (5) Å^3	0.37 × 0.32 × 0.10 mm
Z = 2

Data collection

Bruker APEX area-detector diffractometer	1683 independent reflections
Radiation source: fine-focus sealed tube	921 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.012
φ and ω scan	θmax = 25.2°, θmin = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2002)	h = −6→7
Tmin = 0.965, Tmax = 0.986	k = −8→8
2594 measured reflections	l = −13→10

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)] = 0.054	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.126	H atoms treated by a mixture of independent and constrained refinement
S = 1.27	w = 1/[σ^2(Fo^2) + (0.0449P)^2 + 0.2061P] where P = (Fo^2 + 2Fc^2)/3
1683 reflections	(Δ/σ)max < 0.001
140 parameters	Δρmax = 0.19 e Å^−3
1 restraint	Δρmin = −0.19 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	0.4747 (5)	1.0781 (5)	0.8282 (3)	0.0568 (9)
O2	0.9903 (5)	0.6723 (5)	1.0063 (3)	0.0593 (9)
N1	0.4034 (5)	0.7559 (6)	0.8161 (3)	0.0456 (9)
N2	0.7301 (6)	0.8671 (6)	0.9162 (4)	0.0445 (9)
C1	−0.0299 (6)	0.7622 (7)	0.5309 (4)	0.0526 (11)
H1	−0.1453	0.7556	0.5684	0.063*
C2	−0.0592 (8)	0.7551 (8)	0.4033 (5)	0.0635 (14)
H2	−0.1938	0.7434	0.3551	0.076*
C3	0.1079 (9)	0.7650 (9)	0.3459 (4)	0.0751 (16)
H3	0.0878	0.7610	0.2591	0.090*
C4	0.3051 (9)	0.7811 (12)	0.4182 (5)	0.0817 (19)
H4	0.4199	0.7871	0.3802	0.098*
C5	0.3348 (7)	0.7884 (10)	0.5465 (4)	0.0669 (15)
H5	0.4698	0.7999	0.5942	0.080*
C6	0.1686 (6)	0.7790 (6)	0.6050 (4)	0.0415 (9)
C7	0.1892 (6)	0.7882 (8)	0.7447 (4)	0.0504 (11)
H7A	0.1421	0.9135	0.7666	0.060*
H7B	0.0976	0.6923	0.7694	0.060*
C8	0.5309 (7)	0.9147 (7)	0.8510 (4)	0.0433 (10)
C9	0.8115 (7)	0.6871 (6)	0.9469 (4)	0.0410 (9)
C10	0.6700 (7)	0.5317 (7)	0.9024 (4)	0.0476 (11)
H10	0.7127	0.4045	0.9169	0.057*
C11	0.4775 (7)	0.5722 (7)	0.8404 (4)	0.0466 (11)
H11	0.3880	0.4703	0.8118	0.056*
H1N	0.816 (7)	0.960 (7)	0.934 (4)	0.052 (14)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.054 (2)	0.051 (2)	0.058 (2)	0.0088 (16)	−0.0062 (15)	0.0073 (16)
O2	0.0415 (15)	0.0549 (19)	0.0692 (18)	0.0087 (16)	−0.0168 (13)	0.0028 (18)
N1	0.0380 (18)	0.058 (2)	0.0369 (17)	0.0010 (18)	−0.0003 (13)	−0.0029 (18)
N2	0.0374 (19)	0.042 (2)	0.047 (2)	−0.0009 (16)	−0.0056 (15)	−0.0007 (16)
C1	0.043 (2)	0.051 (3)	0.057 (3)	−0.001 (2)	−0.0045 (18)	0.001 (2)
C2	0.066 (3)	0.053 (3)	0.057 (3)	0.003 (2)	−0.021 (2)	−0.005 (3)
C3	0.104 (4)	0.077 (4)	0.037 (2)	0.003 (4)	−0.002 (3)	−0.005 (3)
C4	0.078 (3)	0.116 (6)	0.057 (3)	−0.003 (4)	0.027 (3)	−0.001 (4)
C5	0.046 (2)	0.106 (5)	0.047 (2)	−0.002 (3)	0.0072 (19)	−0.003 (3)
C6	0.041 (2)	0.040 (2)	0.041 (2)	−0.0023 (19)	0.0024 (15)	−0.0036 (19)
C7	0.035 (2)	0.068 (3)	0.047 (2)	−0.002 (2)	0.0058 (16)	0.000 (2)
C8	0.045 (2)	0.047 (3)	0.035 (2)	0.001 (2)	0.0018 (18)	0.001 (2)
C9	0.048 (2)	0.042 (2)	0.0320 (19)	0.001 (2)	0.0057 (17)	0.0006 (19)
C10	0.059 (3)	0.044 (3)	0.038 (2)	0.004 (2)	0.0074 (19)	0.0000 (19)
C11	0.052 (3)	0.049 (3)	0.037 (2)	−0.009 (2)	0.0064 (19)	−0.003 (2)

Geometric parameters (Å, º)

O1—C8	1.203 (5)	C3—C4	1.369 (7)
O2—C9	1.217 (5)	C3—H3	0.9300
N1—C11	1.371 (6)	C4—C5	1.375 (7)
N1—C8	1.387 (5)	C4—H4	0.9300
N1—C7	1.471 (5)	C5—C6	1.370 (6)
N2—C9	1.373 (6)	C5—H5	0.9300
N2—C8	1.387 (5)	C6—C7	1.505 (5)
N2—H1N	0.85 (5)	C7—H7A	0.9700
C1—C2	1.368 (7)	C7—H7B	0.9700
C1—C6	1.384 (5)	C9—C10	1.439 (6)
C1—H1	0.9300	C10—C11	1.330 (6)
C2—C3	1.368 (7)	C10—H10	0.9300
C2—H2	0.9300	C11—H11	0.9300
C11—N1—C8	121.3 (3)	C5—C6—C1	117.9 (4)
C11—N1—C7	120.2 (4)	C5—C6—C7	123.9 (3)
C8—N1—C7	118.4 (4)	C1—C6—C7	118.2 (3)
C9—N2—C8	128.1 (4)	N1—C7—C6	114.0 (3)
C9—N2—H1N	116 (3)	N1—C7—H7A	108.7
C8—N2—H1N	116 (3)	C6—C7—H7A	108.7
C2—C1—C6	121.0 (4)	N1—C7—H7B	108.7
C2—C1—H1	119.5	C6—C7—H7B	108.7
C6—C1—H1	119.5	H7A—C7—H7B	107.6
C1—C2—C3	120.6 (4)	O1—C8—N2	123.0 (4)
C1—C2—H2	119.7	O1—C8—N1	123.6 (4)
C3—C2—H2	119.7	N2—C8—N1	113.4 (4)
C2—C3—C4	119.0 (4)	O2—C9—N2	119.2 (4)
C2—C3—H3	120.5	O2—C9—C10	126.5 (4)
C4—C3—H3	120.5	N2—C9—C10	114.3 (4)
C3—C4—C5	120.6 (5)	C11—C10—C9	119.1 (4)
C3—C4—H4	119.7	C11—C10—H10	120.4
C5—C4—H4	119.7	C9—C10—H10	120.4
C6—C5—C4	121.0 (4)	C10—C11—N1	123.7 (4)
C6—C5—H5	119.5	C10—C11—H11	118.2
C4—C5—H5	119.5	N1—C11—H11	118.2

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H1N···O2^i	0.85 (5)	1.97 (5)	2.813 (5)	174 (5)

Symmetry code: (i) −x+2, y+1/2, −z+2.