Methyl 2-hy­droxy-4-iodo­benzoate

The title compound forms a sheet structure of dimers exhibiting intra- and inter­molecular hydrogen bonds.

Abstract

The structure of the title compound, C₈H₇IO₃, at 90 K has monoclinic (P2₁/c) symmetry. The extended structure is layered and displays inter­molecular and intra­molecular hydrogen bonding arising from the same OH group.

Structure description

2-Hy­droxy­benzoic acid methyl ester (C₈H₈O₃), commonly known as methyl salicylate, and its derivatives have been shown to display biological effects such as anti-inflammatory, anti-fungal, and process signaling (Yoon et al., 2019 ▸; Li et al., 2016 ▸; Park et al., 2007 ▸). It can also be found in various foods (Duthie & Wood, 2011 ▸). The title compound, 2-hy­droxy-4-iodo­benzoic acid methyl ester (methyl 4-iodo­salicylate, C₈H₇IO₃) allows for an effective way of incorporating the said methyl salicylates within larger organic mol­ecules, using such methodologies as McClure protocols (Franchi et al., 2010 ▸; McClure et al., 2001 ▸), Stille (Yoon et al., 2019 ▸; Stille, 1986 ▸) and Suzuki–Miyaura reactions (Fracaroli et al., 2014 ▸; Miyaura et al., 1979 ▸), which take advantage of the iodine atom at the 4-position of the aromatic ring for the formation of carbon–carbon bonds. The iodine atom is also capable of forming supra­molecular synthons, which may be useful for crystal engineering (Desiraju, 1995 ▸; Cherukuvada et al., 2016 ▸; Mitchell et al., 2023 ▸).

At 90 K the title compound displays monoclinic (P2₁/c) symmetry with one mol­ecule in the asymmetric unit (Fig. 1 ▸). Inter­molecular hydrogen bonding inter­actions occur between the hy­droxy groups of one mol­ecule and the carbonyl oxygen atom of the methyl ester of an adjacent mol­ecule to form a centrosymmetric dimeric pair (Table 1 ▸, Fig. 2 ▸) with H⋯O = 2.53 (4) Å. An O3—H3⋯O2 intra­molecular hydrogen bond also exists with an H⋯O distance of 2.05 (4) Å. The C5⋯C8 [3.326 (3) Å] and O3⋯H1C (2.51 Å) inter­actions provide the only short contacts between the stacks of offset ( 02) parallel sheets, which make up the crystal (Fig. 3 ▸). These sheets, in turn, contain the inversion-generated hydrogen-bonded dimers (Fig. 2 ▸). The non-hydrogen atoms of the mol­ecule are essentially coplanar with no displacement from the mean mol­ecular plane greater than 0.132 Å (Fig. 4 ▸).

Figure 1.

The mol­ecular structure of the title compound showing 50% displacement ellipsoids. The intra­molecular hydrogen bond is indicated by a red dashed line.

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3⋯O2	0.70 (4)	2.05 (4)	2.670 (3)	149 (4)
O3—H3⋯O2i	0.70 (4)	2.53 (4)	3.087 (2)	139 (4)

Symmetry code: (i) .

Figure 2.

The dimer of title compound showing intra- and inter­molecular hydrogen bonds depicted with blue dashed lines with corresponding O⋯H distances for each O—H⋯O inter­action.

Figure 3.

Packing diagram viewed perpendicular to ( 02).

Figure 4.

Packing diagram viewed along b-axis and parallel to ( 02).

Crystallization

Methyl 4-iodo­salicylate (32.8 mg, 0.118 mmol) was added to a 20 ml scintillation vial to which benzene (∼2 ml) was added, and the vial shaken until the compound dissolved. The resulting solution was then left undisturbed, lightly capped, and in the dark for one week to allow for crystal formation while the solvent slowly evaporated.

Refinement

Crystal data, data collection, and structure refinement details are summarized in Table 2 ▸.

Table 2. Experimental details.

Crystal data
Chemical formula	C8H7IO3
M r	278.04
Crystal system, space group	Monoclinic, P21/c
Temperature (K)	90
a, b, c (Å)	4.3286 (8), 21.334 (4), 9.2941 (16)
β (°)	93.744 (4)
V (Å3)	856.4 (3)
Z	4
Radiation type	Mo Kα
μ (mm−1)	3.70
Crystal size (mm)	0.80 × 0.20 × 0.02
Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Krause et al., 2015 ▸)
T min, T max	0.564, 0.747
No. of measured, independent and observed [I > 2σ(I)] reflections	23320, 3651, 3315
R int	0.049
(sin θ/λ)max (Å−1)	0.809
Refinement
R[F 2 > 2σ(F 2)], wR(F 2), S	0.030, 0.057, 1.11
No. of reflections	3651
No. of parameters	114
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)	1.27, −1.92

Computer programs: APEX2 and SAINT V8.40B (Bruker, 2016 ▸), SHELXT2018/2 (Sheldrick, 2015a ▸), SHELXL2018/3 (Sheldrick, 2015b ▸) and OLEX2 (Dolomanov et al., 2009 ▸).

Supplementary Material

CCDC reference: 2352344

Additional supporting information: crystallographic information; 3D view; checkCIF report

full crystallographic data

Crystal data

C8H7IO3	F(000) = 528
Mr = 278.04	Dx = 2.156 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 4.3286 (8) Å	Cell parameters from 6811 reflections
b = 21.334 (4) Å	θ = 2.9–34.1°
c = 9.2941 (16) Å	µ = 3.70 mm−1
β = 93.744 (4)°	T = 90 K
V = 856.4 (3) Å3	Plate, pale yellow
Z = 4	0.80 × 0.20 × 0.02 mm

Data collection

Bruker APEXII CCD diffractometer	3315 reflections with I > 2σ(I)
φ and ω scans	Rint = 0.049
Absorption correction: multi-scan (SADABS; Krause et al., 2015)	θmax = 35.1°, θmin = 2.4°
Tmin = 0.564, Tmax = 0.747	h = −6→6
23320 measured reflections	k = −33→34
3651 independent reflections	l = −14→15

Refinement

Refinement on F2	Primary atom site location: dual
Least-squares matrix: full	Hydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.030	H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.057	w = 1/[σ2(Fo2) + 1.660P] where P = (Fo2 + 2Fc2)/3
S = 1.11	(Δ/σ)max = 0.001
3651 reflections	Δρmax = 1.27 e Å−3
114 parameters	Δρmin = −1.92 e Å−3
0 restraints

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Refinement. The O-bound H atom was located in a difference map and its position was freely refined. The C-bound H atoms were geometrically placed (C—H = 0.95–0.98 Å) and refined as riding atoms.

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

	x	y	z	Uiso*/Ueq
I1	0.05964 (3)	0.25795 (2)	0.54095 (2)	0.01430 (4)
O3	0.7859 (4)	0.39459 (9)	0.91310 (18)	0.0170 (3)
O1	0.4603 (4)	0.56516 (8)	0.72915 (18)	0.0180 (3)
O2	0.7790 (4)	0.51960 (9)	0.89865 (19)	0.0212 (4)
C6	0.2313 (5)	0.34266 (10)	0.6295 (2)	0.0127 (4)
C7	0.4516 (5)	0.34172 (10)	0.7453 (2)	0.0128 (4)
H7	0.522507	0.302965	0.785568	0.015*
C8	0.5675 (5)	0.39821 (10)	0.8018 (2)	0.0121 (3)
C1	0.5827 (6)	0.62513 (11)	0.7783 (3)	0.0203 (5)
H1A	0.499780	0.658300	0.713823	0.030*
H1B	0.809060	0.624553	0.777897	0.030*
H1C	0.522278	0.633151	0.876394	0.030*
C5	0.1189 (5)	0.39860 (11)	0.5688 (2)	0.0161 (4)
H5	−0.033554	0.398522	0.490504	0.019*
C3	0.4577 (5)	0.45534 (10)	0.7425 (2)	0.0123 (4)
C2	0.5823 (5)	0.51534 (11)	0.7990 (2)	0.0144 (4)
C4	0.2359 (5)	0.45406 (10)	0.6259 (2)	0.0156 (4)
H4	0.163744	0.492573	0.584857	0.019*
H3	0.836 (8)	0.4252 (17)	0.929 (4)	0.025 (9)*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
I1	0.01408 (6)	0.01099 (7)	0.01764 (7)	−0.00031 (5)	−0.00056 (4)	−0.00134 (5)
O3	0.0173 (8)	0.0173 (8)	0.0153 (7)	0.0008 (6)	−0.0061 (6)	−0.0004 (6)
O1	0.0241 (8)	0.0104 (7)	0.0188 (8)	−0.0031 (6)	−0.0048 (6)	0.0007 (6)
O2	0.0210 (8)	0.0204 (9)	0.0211 (8)	−0.0015 (6)	−0.0083 (6)	−0.0031 (6)
C6	0.0114 (8)	0.0128 (9)	0.0138 (9)	−0.0012 (7)	0.0009 (7)	−0.0017 (7)
C7	0.0128 (9)	0.0120 (9)	0.0136 (9)	0.0008 (7)	0.0011 (7)	0.0006 (7)
C8	0.0103 (8)	0.0155 (9)	0.0105 (8)	0.0020 (7)	0.0003 (6)	0.0010 (7)
C1	0.0282 (12)	0.0114 (10)	0.0211 (11)	−0.0062 (8)	0.0005 (9)	−0.0021 (8)
C5	0.0178 (10)	0.0137 (10)	0.0158 (9)	−0.0004 (7)	−0.0061 (7)	0.0005 (7)
C3	0.0132 (9)	0.0108 (9)	0.0128 (9)	0.0003 (7)	−0.0010 (7)	0.0004 (7)
C2	0.0140 (9)	0.0152 (10)	0.0138 (9)	−0.0006 (7)	0.0007 (7)	−0.0011 (7)
C4	0.0179 (10)	0.0104 (9)	0.0177 (10)	0.0002 (7)	−0.0053 (8)	0.0012 (7)

Geometric parameters (Å, º)

I1—C6	2.101 (2)	C8—C3	1.407 (3)
O3—C8	1.357 (3)	C1—H1A	0.9800
O3—H3	0.70 (4)	C1—H1B	0.9800
O1—C1	1.447 (3)	C1—H1C	0.9800
O1—C2	1.336 (3)	C5—H5	0.9500
O2—C2	1.220 (3)	C5—C4	1.379 (3)
C6—C7	1.391 (3)	C3—C2	1.472 (3)
C6—C5	1.394 (3)	C3—C4	1.400 (3)
C7—H7	0.9500	C4—H4	0.9500
C7—C8	1.395 (3)
C8—O3—H3	107 (3)	H1A—C1—H1C	109.5
C2—O1—C1	115.15 (18)	H1B—C1—H1C	109.5
C7—C6—I1	119.85 (16)	C6—C5—H5	121.0
C7—C6—C5	121.9 (2)	C4—C5—C6	118.0 (2)
C5—C6—I1	118.20 (15)	C4—C5—H5	121.0
C6—C7—H7	120.3	C8—C3—C2	120.44 (19)
C6—C7—C8	119.4 (2)	C4—C3—C8	118.89 (19)
C8—C7—H7	120.3	C4—C3—C2	120.63 (19)
O3—C8—C7	116.94 (19)	O1—C2—C3	113.23 (18)
O3—C8—C3	123.3 (2)	O2—C2—O1	122.9 (2)
C7—C8—C3	119.80 (19)	O2—C2—C3	123.8 (2)
O1—C1—H1A	109.5	C5—C4—C3	122.0 (2)
O1—C1—H1B	109.5	C5—C4—H4	119.0
O1—C1—H1C	109.5	C3—C4—H4	119.0
H1A—C1—H1B	109.5
I1—C6—C7—C8	178.99 (15)	C8—C3—C2—O1	178.4 (2)
I1—C6—C5—C4	−179.01 (17)	C8—C3—C2—O2	−1.0 (3)
O3—C8—C3—C2	1.0 (3)	C8—C3—C4—C5	0.9 (3)
O3—C8—C3—C4	178.8 (2)	C1—O1—C2—O2	1.2 (3)
C6—C7—C8—O3	−178.90 (19)	C1—O1—C2—C3	−178.26 (19)
C6—C7—C8—C3	0.9 (3)	C5—C6—C7—C8	−0.8 (3)
C6—C5—C4—C3	−0.9 (4)	C2—C3—C4—C5	178.8 (2)
C7—C6—C5—C4	0.8 (3)	C4—C3—C2—O1	0.6 (3)
C7—C8—C3—C2	−178.8 (2)	C4—C3—C2—O2	−178.8 (2)
C7—C8—C3—C4	−0.9 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O2	0.70 (4)	2.05 (4)	2.670 (3)	149 (4)
O3—H3···O2i	0.70 (4)	2.53 (4)	3.087 (2)	139 (4)

Symmetry code: (i) −x+2, −y+1, −z+2.

Funding Statement

Funding for this research was provided by: National Science Foundation (award No. DMR-2003932).