2,4-Dibromo­naphthalen-1-ol

In the essentially planar (r.m.s. deviation = 0.023 Å) title compound, C₁₀H₆Br₂O, an intra­molecular O—H...Br hydrogen bond generates an S(5) ring. In the crystal, mol­ecules are linked by an ...O—H...O—H...O— C(2) chain extending along [100], which involves the same H atom that participates in the intra­molecular hydrogen bond. Aromatic π–π inter­actions [centroid–centroid separation = 3.737 (4) Å] help to consolidate the packing.

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](C-C) = 0.009 Å
• R factor = 0.042
• wR factor = 0.089
• Data-to-parameter ratio = 18.8

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT341_ALERT_3_C Low Bond Precision on  C-C Bonds ...............     0.0085 Ang
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          2
PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L=  0.600         11

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           27.90
           From the CIF: _reflns_number_total               2239
           Count of symmetry unique reflns         1376
           Completeness (_total/calc)            162.72%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured       863
           Fraction of Friedel pairs measured     0.627
           Are heavy atom types Z>Si present        yes
PLAT005_ALERT_5_G No _iucr_refine_instructions_details in CIF ....          ?
PLAT431_ALERT_2_G Short Inter HL..A Contact  Br1    ..  Br2     ..       3.54 Ang.

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   3 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   3 ALERT level G = General information/check it is not something unexpected

   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
   2 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

The crystal structure of 2-bromonaphthalene (Chanh, et al., 1973) has been published which is related to the title compound (Fig. 1).

The molecule of the title compound is planar with r.m.s. deviation of 0.0234 Å. The Br2 atom has maximum deviation from the mean plane and its value is 0.0574 (27) Å. There exists an intra-molecular hydrogen bond of O—H···Br type (Table 1, Fig. 1) and complete S(5) ring motif (Bernstein et al., 1995). The molecules are stabilized in the form of polymeric chains due to intermolecular H-bonding of O—H···O type (Table 1, Fig. 2). Due to these hydrogen bonds a chain of ···O—H···O—H···O— exists. The π–π interactions between the benzene rings (C1—C6) and (C1/C6—C10) of the naphthalen group at a distance of 3.737 (4) Å help to consolidate the packing.

Related literature

For a related crystal structure, see: Chanh et al. (1973): For graph-set notation, see: Bernstein et al. (1995).

S2. Experimental

Bromine (2.9 ml, 9.2 g, 30 mmol, 2 eq) was added as drops to an ice-chilled solution of α,β-unsaturated-1-tetralone (2.2 g, 15 mmol, 1 eq) in CHCl₃ (50 ml) and was stirred for 1 h. Et₃N (3 ml, 2.2 g, 22 mmol, 1.5 eq) was added to the reaction mixture followed by 2 h stirring at room temperature. After the commencement of reaction, the reaction mixture was neutralized with aq HCl (15 ml). The organic layer was washed with H₂O (3 × 25 ml), dried over anhydrous Na₂SO₄ and concentrated under reduced pressure to afford the colorless needles of (I).

Yield: 2.4 g, 52%, m.p. 499 K.

S3. Refinement

The H-atoms were positioned geometrically with (O–H = 0.82, C–H = 0.93 Å) and refined as riding with U_iso(H) = xU_eq(C, O), where x = 1.5 for hydroxy and x = 1.2 for aryl H-atoms.

Computing details

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures

	Fig. 1. View of the title compound with displacement ellipsoids drawn at the 50% probability level. The dotted line indicates the intramolecular H-bond.
	Fig. 2. The partial packing of (I), which shows that molecules form polymeric chains.

2,4-Dibromonaphthalen-1-ol

Crystal data

C10H6Br2O	F(000) = 576
Mr = 301.97	Dx = 2.099 Mg m^−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 1410 reflections
a = 4.1225 (3) Å	θ = 2.8–27.9°
b = 14.4441 (11) Å	µ = 8.44 mm^−1
c = 16.0490 (14) Å	T = 296 K
V = 955.65 (13) Å^3	Needle, colorless
Z = 4	0.32 × 0.14 × 0.12 mm

Data collection

Bruker Kappa APEXII CCD diffractometer	2239 independent reflections
Radiation source: fine-focus sealed tube	1410 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.045
Detector resolution: 7.60 pixels mm^-1	θmax = 27.9°, θmin = 2.8°
ω scans	h = −5→5
Absorption correction: multi-scan (SADABS; Bruker, 2005)	k = −15→19
Tmin = 0.254, Tmax = 0.365	l = −20→20
5060 measured reflections

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)] = 0.042	H-atom parameters constrained
wR(F^2) = 0.089	w = 1/[σ^2(Fo^2) + (0.0309P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 0.96	(Δ/σ)max < 0.001
2239 reflections	Δρmax = 0.47 e Å^−3
119 parameters	Δρmin = −0.41 e Å^−3
0 restraints	Absolute structure: Flack (1983), 863 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.01 (3)

Special details

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su'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
Br1	0.45967 (15)	0.18900 (4)	0.18041 (4)	0.0493 (2)
Br2	1.06884 (18)	−0.15734 (4)	0.19773 (5)	0.0624 (3)
O1	0.6998 (11)	0.1798 (3)	−0.0029 (3)	0.0463 (16)
C1	0.9478 (14)	0.0326 (3)	0.0024 (3)	0.0333 (17)
C2	0.7730 (14)	0.1034 (4)	0.0449 (4)	0.0343 (19)
C3	0.6882 (14)	0.0934 (4)	0.1244 (4)	0.036 (2)
C4	0.7718 (13)	0.0149 (4)	0.1698 (4)	0.039 (2)
C5	0.9399 (15)	−0.0536 (4)	0.1318 (4)	0.0417 (19)
C6	1.0379 (14)	−0.0490 (4)	0.0474 (3)	0.0377 (19)
C7	1.2132 (16)	−0.1172 (4)	0.0024 (5)	0.048 (3)
C8	1.2958 (16)	−0.1080 (5)	−0.0777 (4)	0.058 (3)
C9	1.2149 (16)	−0.0287 (5)	−0.1202 (5)	0.059 (3)
C10	1.0428 (15)	0.0408 (4)	−0.0816 (3)	0.045 (2)
H1	0.57717	0.21391	0.02304	0.0692*
H4	0.71293	0.00947	0.22552	0.0471*
H7	1.27375	−0.17112	0.03010	0.0583*
H8	1.40791	−0.15515	−0.10460	0.0694*
H9	1.27695	−0.02190	−0.17559	0.0702*
H10	0.98850	0.09384	−0.11132	0.0537*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Br1	0.0513 (4)	0.0432 (3)	0.0535 (4)	−0.0002 (3)	0.0022 (4)	−0.0087 (3)
Br2	0.0679 (5)	0.0465 (4)	0.0727 (5)	0.0007 (3)	−0.0084 (4)	0.0200 (4)
O1	0.049 (3)	0.034 (2)	0.056 (3)	0.002 (2)	0.002 (2)	0.007 (2)
C1	0.030 (3)	0.036 (3)	0.034 (3)	−0.005 (3)	−0.008 (3)	−0.005 (3)
C2	0.034 (3)	0.030 (3)	0.039 (4)	−0.008 (3)	−0.009 (3)	0.003 (3)
C3	0.033 (3)	0.036 (4)	0.038 (4)	−0.008 (3)	0.000 (3)	−0.006 (3)
C4	0.041 (4)	0.039 (3)	0.038 (4)	−0.008 (3)	−0.006 (3)	0.005 (3)
C5	0.039 (3)	0.037 (3)	0.049 (4)	−0.006 (3)	−0.014 (3)	0.008 (3)
C6	0.033 (3)	0.031 (3)	0.049 (4)	−0.007 (3)	−0.012 (3)	−0.002 (3)
C7	0.047 (4)	0.042 (4)	0.056 (5)	0.004 (3)	−0.017 (4)	−0.012 (4)
C8	0.052 (4)	0.063 (5)	0.059 (6)	0.011 (4)	−0.004 (4)	−0.026 (5)
C9	0.052 (5)	0.081 (6)	0.043 (5)	−0.001 (4)	0.003 (4)	−0.006 (4)
C10	0.042 (4)	0.049 (3)	0.044 (4)	−0.002 (3)	−0.012 (3)	0.001 (3)

Geometric parameters (Å, º)

Br1—C3	1.898 (6)	C5—C6	1.415 (8)
Br2—C5	1.910 (6)	C6—C7	1.419 (9)
O1—C2	1.377 (7)	C7—C8	1.337 (10)
O1—H1	0.8200	C8—C9	1.374 (10)
C1—C2	1.425 (8)	C9—C10	1.377 (9)
C1—C10	1.409 (7)	C4—H4	0.9300
C1—C6	1.431 (7)	C7—H7	0.9300
C2—C3	1.331 (9)	C8—H8	0.9300
C3—C4	1.391 (8)	C9—H9	0.9300
C4—C5	1.353 (8)	C10—H10	0.9300
C2—O1—H1	110.00	C1—C6—C5	116.6 (5)
C2—C1—C6	118.7 (5)	C6—C7—C8	123.4 (6)
C2—C1—C10	122.6 (5)	C7—C8—C9	119.9 (7)
C6—C1—C10	118.7 (5)	C8—C9—C10	120.6 (7)
O1—C2—C1	114.8 (5)	C1—C10—C9	120.8 (5)
O1—C2—C3	124.3 (5)	C3—C4—H4	121.00
C1—C2—C3	120.9 (5)	C5—C4—H4	120.00
Br1—C3—C4	117.9 (5)	C6—C7—H7	118.00
C2—C3—C4	121.7 (6)	C8—C7—H7	118.00
Br1—C3—C2	120.4 (5)	C7—C8—H8	120.00
C3—C4—C5	119.1 (6)	C9—C8—H8	120.00
Br2—C5—C6	119.2 (4)	C8—C9—H9	120.00
C4—C5—C6	122.9 (6)	C10—C9—H9	120.00
Br2—C5—C4	117.8 (5)	C1—C10—H10	120.00
C1—C6—C7	116.6 (5)	C9—C10—H10	120.00
C5—C6—C7	126.9 (6)
C6—C1—C2—O1	179.3 (5)	Br1—C3—C4—C5	−178.8 (4)
C6—C1—C2—C3	−1.5 (8)	C2—C3—C4—C5	−0.9 (9)
C10—C1—C2—O1	1.0 (8)	C3—C4—C5—Br2	176.9 (4)
C10—C1—C2—C3	−179.8 (6)	C3—C4—C5—C6	0.5 (9)
C2—C1—C6—C5	1.0 (8)	Br2—C5—C6—C1	−176.9 (4)
C2—C1—C6—C7	−179.7 (5)	Br2—C5—C6—C7	3.8 (9)
C10—C1—C6—C5	179.4 (5)	C4—C5—C6—C1	−0.5 (9)
C10—C1—C6—C7	−1.3 (8)	C4—C5—C6—C7	−179.8 (6)
C2—C1—C10—C9	179.2 (6)	C1—C6—C7—C8	0.4 (9)
C6—C1—C10—C9	0.9 (9)	C5—C6—C7—C8	179.6 (6)
O1—C2—C3—Br1	−1.5 (8)	C6—C7—C8—C9	1.0 (10)
O1—C2—C3—C4	−179.4 (5)	C7—C8—C9—C10	−1.5 (10)
C1—C2—C3—Br1	179.3 (4)	C8—C9—C10—C1	0.5 (10)
C1—C2—C3—C4	1.4 (9)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···Br1	0.82	2.60	3.107 (5)	122
O1—H1···O1^i	0.82	2.21	2.893 (6)	141

Symmetry code: (i) x−1/2, −y+1/2, −z.