4-Hydroxy­benzamide

The crystal structure of the title compound, C₇H₇NO₂, has not hitherto been published. The structure is stabilized by inter­molecular O—H...O and N—H...O hydrogen bonds. The topology of the hydrogen-bond network can be characterized by the graph-set notation R₄⁴(20).

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.047
• wR factor = 0.044
• Data-to-parameter ratio = 7.3

checkCIF/PLATON results

No syntax errors found





Alert level A
PLAT029_ALERT_3_A _diffrn_measured_fraction_theta_full Low .......       0.88

Alert level B
GOODF01_ALERT_2_B  The least squares goodness of fit parameter lies
            outside the range 0.60 <> 4.00
            Goodness of fit given =      5.410
REFLT03_ALERT_3_B  Reflection count < 90% complete (theta max?)
           From the CIF: _diffrn_reflns_theta_max           30.61
           From the CIF: _diffrn_reflns_theta_full          30.61
           From the CIF: _reflns_number_total               1754
           TEST2: Reflns within _diffrn_reflns_theta_max
           Count of symmetry unique reflns         1986
           Completeness (_total/calc)             88.32%
REFNR01_ALERT_3_B  Ratio of reflections to parameters is < 8 for a
            centrosymmetric structure
            sine(theta)/lambda                0.7165
            Proportion of unique data used    0.4966
            Ratio reflections to parameters   7.3193
SHFSU01_ALERT_2_B  The absolute value of parameter shift to su ratio > 0.10
            Absolute value of the parameter shift to su ratio given   0.115
            Additional refinement cycles may be required.
PLAT080_ALERT_2_B Maximum Shift/Error ............................       0.11
PLAT087_ALERT_2_B Unsatisfactory S value (Too High) ..............       5.41
PLAT088_ALERT_3_B Poor Data / Parameter Ratio ....................       7.32

Alert level C
PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent .....          ?
PLAT166_ALERT_4_C S.U's Given on Coordinates for calc-flagged ....         H1
PLAT166_ALERT_4_C S.U's Given on Coordinates for calc-flagged ....         H2
PLAT166_ALERT_4_C S.U's Given on Coordinates for calc-flagged ....         H3
PLAT166_ALERT_4_C S.U's Given on Coordinates for calc-flagged ....         H4
PLAT166_ALERT_4_C S.U's Given on Coordinates for calc-flagged ....         H5
PLAT166_ALERT_4_C S.U's Given on Coordinates for calc-flagged ....         H6
PLAT166_ALERT_4_C S.U's Given on Coordinates for calc-flagged ....         H7

Alert level G
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K

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

   2 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
   4 ALERT type 3 Indicator that the structure quality may be low
   7 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

The molecular structure of the title compound, (III), is presented in Fig. 2. The geometric parameters of the hydrogen bonds are summarized in Table 1. The molecular packing is shown in Figs. 2 and 3.

The structure of its monohydrate was determined some years ago (Kashino et al., 1991). The unit-cell volume of (III) is 642.5 (3) ų, whereas for the hydrate it is 746.7 (2) ų. In (III), there are two N—H···O and one O—H···O intermolecular hydrogen bonds. In the monohydrate, there are two N—H···O, two O(water)—H···O and one O—H···O(water) intermolecular hydrogen bonds.

The crystal structures of 2-hydroxybenzamide (salicylamide), (I) (Sasada et al., 1964; Pertlik, 1990), and 3-hydroxybenzamide, (II) (Katsube et al., 1966), have also been determined previously.

Related literature

For related literature, see: Kashino et al. (1991); Katsube et al. (1966); Pertlik (1990); Sasada et al. (1964); Etter (1990).

S2. Experimental

A commercial sample of 4-hydroxybenzamide (Sigma-Aldrich Co. Ltd, St. Louis, USA) was used. Crystals of (III) were grown by slow evaporation of an acetone solution.

S3. Refinement

The crystals were of poor quality and weakly diffracting, which accounts for the low fraction of measured reflections. The H atoms were placed in idealized locations, with C—H = 0.96 (2)–0.99 (2) Å, O—H = 0.90 (3) Å and N—H = 0.90 (3)–0.93 (3) Å, and refined as riding, with U_iso(H) = 1.2U_eq(C,N) or 1.5U_eq(O,C-methyl).

Computing details

Data collection: CrystalClear (Rigaku/MSC, 2005); cell refinement: CrystalClear; data reduction: CrystalStructure (Rigaku/MSC, 2005); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003); molecular graphics: ORTEX (McArdle, 1993) and ORTEPIII (Burnett & Johnson, (1996); software used to prepare material for publication: CrystalStructure.

Figures

	Fig. 1. Chemical schemes for compounds (I), (II) and (III).
	Fig. 2. The molecular structure of (III), with the atomic numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 3. Projection of the molecular packing of (III) along the a axis. Dashed lines indicate hydrogen bonds.
	Fig. 4. Projection of the molecular packing of (III) along the b axis. Dashed lines indicate hydrogen bonds.

4-Hydroxybenzamide

Crystal data

C7H7NO2	F(000) = 288.00
Mr = 137.14	Dx = 1.418 Mg m^−3
Monoclinic, P21/c	Melting point: 433.1 K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71070 Å
a = 4.5828 (15) Å	Cell parameters from 1110 reflections
b = 8.825 (3) Å	θ = 2.6–30.1°
c = 15.888 (5) Å	µ = 0.11 mm^−1
β = 90.770 (7)°	T = 293 K
V = 642.5 (3) Å^3	Prism, colourless
Z = 4	0.30 × 0.20 × 0.20 mm

Data collection

Rigaku Saturn CCD area-detector diffractometer	871 reflections with F^2 > 2σ(F^2)
Detector resolution: 7.31 pixels mm^-1	Rint = 0.031
ω scans	θmax = 30.6°
Absorption correction: multi-scan (Jacobson, 1998)	h = −6→6
Tmin = 0.905, Tmax = 0.979	k = −12→12
5970 measured reflections	l = −22→16
1754 independent reflections

Refinement

Refinement on F	All H-atom parameters refined
R[F^2 > 2σ(F^2)] = 0.047	w = 1/[σ^2(Fo^2) + (0.0492P)^2 + 0.3454P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.044	(Δ/σ)max = 0.115
S = 5.41	Δρmax = 0.32 e Å^−3
871 reflections	Δρmin = −0.15 e Å^−3
119 parameters

Special details

Geometry. ENTER SPECIAL DETAILS OF THE MOLECULAR GEOMETRY

Refinement. Refinement using reflections with F² > 2.0 σ(F²). The weighted R-factor(wR), goodness of fit (S) and R-factor (gt) are based on F, with F set to zero for negative F. The threshold expression of F² > 2.0 σ(F²) is used only for calculating R-factor (gt).

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1	0.7483 (4)	0.1346 (2)	0.30494 (11)	0.0527 (5)
O2	1.0947 (5)	0.2443 (2)	−0.07333 (11)	0.0543 (6)
N3	0.4860 (5)	0.3475 (3)	0.28422 (14)	0.0492 (7)
C4	0.6686 (5)	0.2409 (3)	0.25753 (13)	0.0398 (7)
C5	0.7782 (5)	0.2489 (3)	0.16993 (12)	0.0357 (6)
C6	0.9893 (6)	0.1458 (3)	0.14555 (16)	0.0431 (7)
C7	0.9875 (6)	0.2478 (3)	0.00638 (14)	0.0400 (7)
C8	1.0950 (6)	0.1447 (3)	0.06454 (16)	0.0461 (8)
C9	0.6756 (6)	0.3535 (3)	0.11146 (16)	0.0456 (7)
C10	0.7795 (6)	0.3522 (3)	0.02972 (16)	0.0460 (8)
H1	0.406 (6)	0.334 (3)	0.3373 (18)	0.054 (8)*
H2	0.421 (6)	0.422 (3)	0.250 (2)	0.065 (10)*
H3	0.527 (6)	0.429 (3)	0.1269 (18)	0.054 (8)*
H4	0.704 (6)	0.422 (3)	−0.0127 (19)	0.067 (9)*
H5	0.989 (8)	0.304 (4)	−0.108 (2)	0.098 (15)*
H6	1.243 (7)	0.075 (3)	0.048 (2)	0.074 (10)*
H7	1.054 (6)	0.073 (3)	0.1873 (18)	0.057 (9)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0770 (15)	0.0490 (11)	0.0321 (8)	−0.0021 (11)	0.0042 (9)	0.0073 (9)
O2	0.0657 (14)	0.0658 (15)	0.0316 (9)	0.0105 (13)	0.0122 (9)	0.0015 (10)
N3	0.0632 (17)	0.0505 (16)	0.0343 (11)	0.0026 (14)	0.0132 (11)	0.0018 (12)
C4	0.0483 (16)	0.0407 (15)	0.0303 (11)	−0.0099 (15)	0.0013 (11)	−0.0005 (12)
C5	0.0420 (14)	0.0366 (14)	0.0285 (10)	−0.0048 (12)	0.0025 (10)	−0.0003 (10)
C6	0.0502 (16)	0.0447 (16)	0.0344 (12)	0.0017 (14)	0.0017 (11)	0.0031 (12)
C7	0.0449 (14)	0.0446 (16)	0.0305 (10)	−0.0048 (14)	0.0056 (10)	−0.0039 (12)
C8	0.0506 (17)	0.0485 (17)	0.0392 (13)	0.0070 (15)	0.0058 (12)	−0.0009 (13)
C9	0.0532 (17)	0.0488 (17)	0.0352 (12)	0.0103 (16)	0.0105 (11)	0.0039 (13)
C10	0.0555 (18)	0.0517 (18)	0.0310 (12)	0.0065 (16)	0.0071 (11)	0.0088 (13)

Geometric parameters (Å, º)

O1—C4	1.254 (3)	C9—C10	1.389 (3)
O2—C7	1.365 (3)	O2—H5	0.90 (3)
N3—C4	1.333 (3)	N3—H1	0.93 (3)
C4—C5	1.488 (3)	N3—H2	0.90 (3)
C5—C6	1.387 (4)	C6—H7	0.96 (2)
C5—C9	1.387 (3)	C8—H6	0.96 (3)
C6—C8	1.381 (3)	C9—H3	0.99 (2)
C7—C8	1.383 (4)	C10—H4	0.97 (3)
C7—C10	1.380 (4)
O1—C4—N3	121.1 (2)	C7—O2—H5	111 (2)
O1—C4—C5	119.9 (2)	C4—N3—H1	116.8 (18)
N3—C4—C5	119.0 (2)	C4—N3—H2	122 (2)
C4—C5—C6	118.4 (2)	H1—N3—H2	121 (2)
C4—C5—C9	122.9 (2)	C5—C6—H7	116.9 (17)
C6—C5—C9	118.7 (2)	C8—C6—H7	121.8 (17)
C5—C6—C8	121.3 (2)	C6—C8—H6	121.2 (19)
O2—C7—C8	118.4 (2)	C7—C8—H6	119.4 (19)
O2—C7—C10	121.5 (2)	C5—C9—H3	120.8 (16)
C8—C7—C10	120.1 (2)	C10—C9—H3	119.0 (16)
C6—C8—C7	119.4 (2)	C7—C10—H4	118.6 (18)
C5—C9—C10	120.2 (2)	C9—C10—H4	121.2 (18)
C7—C10—C9	120.2 (2)
O1—C4—C5—C6	−6.2 (4)	C9—C5—C6—C8	−0.8 (4)
O1—C4—C5—C9	172.9 (2)	C5—C6—C8—C7	−0.3 (4)
N3—C4—C5—C6	173.9 (2)	O2—C7—C8—C6	−179.8 (2)
N3—C4—C5—C9	−7.0 (4)	O2—C7—C10—C9	−179.7 (2)
C4—C5—C6—C8	178.4 (2)	C8—C7—C10—C9	−0.5 (4)
C4—C5—C9—C10	−177.9 (2)	C10—C7—C8—C6	0.9 (4)
C6—C5—C9—C10	1.2 (4)	C5—C9—C10—C7	−0.6 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H5···O1^i	0.90 (3)	1.84 (3)	2.706 (2)	161 (2)
N3—H1···O2^ii	0.93 (3)	2.14 (3)	3.017 (3)	156 (2)
N3—H2···O1^iii	0.90 (3)	2.21 (3)	3.088 (3)	166 (2)

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