Crystal structure of 4′-bromo-2,5-dihy­droxy-2′,5′-dimeth­oxy-[1,1′-biphen­yl]-3,4-dicarbo­nitrile

Meany, J.E.; Kelley, S.P.; Rogers, R.D.; Woski, S.A.

doi:10.1107/S2056989016005715

research communications

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 72| Part 5| May 2016| Pages 667-670

doi:10.1107/S2056989016005715

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Crystal structure of 4′-bromo-2,5-dihydroxy-2′,5′-dimethoxy-[1,1′-biphenyl]-3,4-dicarbonitrile

Joseph E. Meany,^a Steven P. Kelley,^a Robin D. Rogers ^b and Stephen A. Woski ^a ^*

^aDepartment of Chemistry, The University of Alabama, Box 870336, Tuscaloosa, AL 35487-0336, USA, and ^bDepartment of Chemistry, McGill University, 801 Sherbrooke St. West, Montreal, Quebec, H3A 0B8, Canada
^*Correspondence e-mail: swoski@ua.edu

Edited by G. Smith, Queensland University of Technology, Australia (Received 25 February 2016; accepted 6 April 2016; online 12 April 2016)

In the crystal of the title substituted hemibiquinone derivative, C₁₆H₁₁BrN₂O₄ or [BrHBQH₂(CN)₂], the substituted benzene rings are rotated about the central C—C bond, forming a dihedral angle of 53.59 (7)°. The ring systems interact through an intramolecular O—H⋯O_methoxy hydrogen bond, which induces a geometry quite different from those in previously reported hemibiquinone structures. In the crystal, the molecules associate through an intermolecular O—H⋯N_nitrile hydrogen bond, forming chains which extend along [100] and are interlinked through very weak C—H⋯N hydrogen bonds, giving a overall two-dimensional structure lying parallel to (010).

Keywords: crystal structure; hemibiquinone; molecular rectifier.

CCDC reference: 1472611

1. Chemical context

Recently, a new class of molecules (hemibiquinones, HBQs) has been reported as potential molecular rectifiers (Meany et al., 2015 ). Biphenyl derivatives have garnered great attention as conductors of electricity (Venkataraman et al., 2006 ). The symmetric nature of the biphenyl and polyphenyl derivatives studied so far allows for reasonable conduction through the π orbitals. Biphenyl derivatives with one electron-rich and one electron-deficient ring may be able to preferentially bias the direction of electron flow through the molecule, thus acting as a molecular diode. The donor–bridge–acceptor model has long been accepted as a basis for the design of molecular rectifiers (Aviram & Ratner, 1974 ). The asymmetric biphenyl structure should allow for conductivity through each of the rings, while the dihedral angle between the two rings decreases orbital overlap and allows for partial isolation of the electron-rich donor and electron-poor acceptor moieties. The efficiency of conduction through a given molecule can be tuned depending on the torsion angle between the two rings.

As one of the series of molecules made for testing rectification through HBQs, the title compound, C₁₆H₁₁BrN₂O₄, [BrHBQH₂(CN)₂], (I) has been isolated as an intermediate in the preparation of an HBQ derivative which can self-assemble on a gold surface. We have developed a selective synthesis for this reduced hemibiquinone derivative that is scalable to gram quantities. Molecule (I) is predicted not to act as a molecular diode itself because both rings act as donor moieties. The oxidation of the hydroquinone ring of (I) would produce a potential rectifier.

Dicyano-functionalized hydroquinones are known for their ability to form hydrogen-bonded networks (Reddy et al., 1996 ) and charge-transfer complexes (Bock et al., 1996 ), sometimes both at once (Ghorai & Mani, 2014 ). They have also been used as rigid ligands in coordination polymers (Kuroda-Sowa et al., 1997 ). However, there are no crystal structures in which a dicyano-functionalized hydroquinone moiety has been appended to another aromatic ring. The present study affords an opportunity to investigate the mutual effects of these two functionalized ring systems on both the geometry of the molecule and its intermolecular interactions.

2. Structural commentary

In the title compound (Fig. 1), the benzene rings are twisted out of a common plane, forming a dihedral angle of 53.59 (7)°, which appears to optimize the 2.7576 (18) Å O3—H⋯O2 intramolecular hydrogen bond (Table 1). The rings are essentially planar although the O3—H group, which participates in the intramolecular hydrogen bond, is displaced slightly out of the plane. Also, the rings are not co-axial with the C4—C7 bond that bridges them. This can be seen in torsion angles involving three carbon atoms from one ring and the bridging carbon atom from the other, which deviate from linearity by ca 5° [C2—C3—C4—C7 = 173.88 (14)°, C6—C5—C4—C7 = −175.45 (14)°, C4—C7—C8—C9 = 174.94 (13)°, C4—C7—C12—C11 = −175.62 (13)°]. This bending of the molecule about its long axis may also be due to hydrogen bonding as it causes the methoxy group to approach the OH group more closely. The aromatic C—C bonds of both rings have a narrow range of distances [from 1.387 (2) to 1.412 (2) Å]. The C—C, C—O, C—N, and C N distances for the molecule are similar to the corresponding distances in 2,3,5,6-tetracyanohydroquinone (Bock et al., 1993 ). The C—C bond distances around the bromodimethoxybenzene ring are close to those in the other hemibiquinone molecules containing this ring (Meany et al., 2015, 2016 ). The C9—C10 bond in (I) [1.408 (2) Å] is longer than the corresponding C1—C6 bond in BrHBQBr (1.334 Å; Meany et al., 2015). The stronger polarization of (I) relative to the starting material should weaken the bond through repulsive effects. The Br1—C1 bond is slightly shorter in (I) [1.885 (1) Å] compared to the starting material [1.898 (4) Å] as well, also suggesting decreased electron density on the dimethoxybenzene ring due to increased polarization. The calculated dipole (B3LYP-DGDZVP) of BrHBQBr is only 1.33 D, compared to 6.17 D for (I).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3A⋯O2	0.72 (3)	2.11 (3)	2.7576 (18)	152 (3)
O4—H4A⋯N1ⁱ	0.79 (2)	2.03 (2)	2.8189 (18)	172 (2)
C2—H2A⋯N2ⁱⁱ	0.93	2.72	3.638 (2)	168
Symmetry codes: (i) x+1, y, z; (ii) $[-x-1, y-{\script{1\over 2}}, -z-{\script{1\over 2}}]$ .

Figure 1
The molecular structure of (I)

, showing the atom-numbering scheme. Displacement ellipsoids are displayed at the 50% probability level. The intramolecular O3—H⋯O2 hydrogen bond is shown as a dashed line.

As in the other reported hemibiquinone molecules (Meany et al., 2015), we seek to use and compare the inter-ring torsion angles in the crystals as a guide compared to gas-phase calculated values. The intramolecular hydrogen bond from the C8 phenol to the O2 methoxy group causes a greater torsion angle than that in the starting HBQ (Meany et al., 2015). In (I), the C5—C4—C7—C8 torsion angle is −126.5 (2)°, compared to −110.9 (5)° in HBQ. DFT (B3LYP-DGDZVP) calculations performed on the target molecule in the gas phase predict an angle of 48.85°. This significant discrepancy is due to packing interactions in the solid phase as well as the additional hydrogen bond. The hydrogen bond is indicated in Fig. 1, while the relative orientations of the rings can be seen in Fig. 2.

Figure 2
Ball-and-stick plot of (I)

, viewed down the C4—C7 bond.

The O3—H⋯O2 intramolecular hydrogen bond points toward the non-bonded electrons on O2 with a total bond angle of 152 (3)°. As a result of the influence of other short contacts and supramolecular interactions (see below), the phenolic C—O—H bond angles deviate when compared to the methoxy C—O—C bond angles: C8—O3—H is 108 (2)°, C11—O4—H is 112.3 (2)°, C3—O2—C14 is 117.9 (1)°, and C6—O1—C13 is 117.2 (1)°. As in other structures, the methoxy groups are aligned mostly in-plane with the benzene ring, C5— C6—O1—C13 being bent out of plane by −4.5 (2)° and C2—C3—O2—C14 bent out of plane by −1.3 (2)°. The C12—C11—O4—H phenol group is also nearly planar, being bent out of plane by 1.3°. However, the hydrogen-bonded phenol is unsurprisingly bent out of plane, C7—C8—O3—H = 38 (2)°. The methoxy methyl groups point away from the sterically restricting groups ortho to these positions.

3. Supramolecular features

Each molecule makes short (less than the sum of the van der Waals radii) contacts to six neighboring molecules (Fig. 3). As in previously reported HBQ structures, rings of like identity are all aligned in parallel planes. All short contacts are associated with Lewis acid–base interactions of some kind, and for each interaction there is one neighboring molecule that acts as a donor and second that acts as an acceptor. Two central molecules in the unit cell stack antiparallel to one another, the quinone rings shifted off-center from one another in the a-axis direction. Both nitrile groups are involved in intermolecular hydrogen-bonding interactions, the first one (O4—H⋯N1) strong, the second one (C2—H⋯N2) weaker but still highly directional. For details, see Table 1. These interactions link molecules along the crystallographic a- and b-axis directions, respectively, forming sheets parallel to (010) (Fig. 4). The quinone rings are aligned parallel to the bc plane diagonal.

Figure 3
Short (less than the sum of the van der Waals radii) contact environment around [BrHBQH₂(CN)₂]. Dashed green lines indicate short contacts. Axes are color coded: red = a axis, green = b axis and blue = c axis.

Figure 4
Hydrogen-bonded sheets along ab. Dashed green lines indicate short contacts. Axes are color coded: red = a axis, green = b axis and blue = c axis.

The remaining two molecules in the unit cell are oriented orthogonally to the central molecules. These molecules are antiparallel to each other, where the dimethoxybenzene rings stack with those of the central pair. Slightly repulsive π-interactions between molecules along b and stacking along c can be seen in Fig. 5. Intercentroid distances for the rings are longer than expected for close π–π interactions at 4.107 (1) Å. However, since the rings are slightly offset from one another, this is not the correct centroid to use. Instead, a close 3.598 (1) Å π-interaction between two intermolecular C9—C10 centroids exists. A centroid calculated for the C7—C8—C9—C11—C12 ring sits 3.574 (1) Å from a centroid for N1—C15—C9—C10—C16—N2, which may be explained by the electron-donating character of the hydroquinone as compared to the dinitrile substituents. The planes of the dimethoxybenzene rings are oriented parallel to the short diagonal of the ac plane.

Figure 5
Unit-cell packing of (I)

, viewed along the a axis. Short contacts show the long ring stacking along the c axis.

4. Synthesis and crystallization

2-Bromo-5-(4-bromo-2,5-dimethoxyphenyl)cyclohexa-2,5-diene-1,4-dione, BrHBQBr, (0.300 g, 0.744 mmol) was dissolved in 350 mL of acetonitrile. In a separate beaker, potassium cyanide (0.124 g, 1.90 mmol) was dissolved in 50 mL of H₂O. Upon pouring the aqueous solution into the organic solution, the mixture immediately changed from a vibrant red to a deep purple. After stirring for 1 h, 50 µL of concentrated HCl solution was added, changing the color of the mixture from purple to bright orange. The mixture was diluted with 50 mL of water and the acetonitrile was removed by rotary evaporation. A tan powder precipitated, which was recovered by filtration and washed with water to yield the crude product. This material was recrystallized from acetone giving 0.196 g (70.4%) of pure material as yellow–orange prisms. ¹H NMR (360 MHz, d₆-acetone) δ = 10.02 (s, 1H, ArOH), 8.75 (s, 1H, ArOH), 7.34 (s, 1H, ArH), 7.24 (s, 1H, ArH), 7.05 (s, 1H, ArH), 3.88 (s, 3H, OCH₃), 3.82 (s, 3H, OCH₃).

5. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. Hydroxyl hydrogen atoms were located from the difference map and their coordinates were refined while the thermal parameters were constrained to ride on the carrier atom with U_iso = 1.5U_eq(O). Hydrogen atoms bonded to carbon were placed in calculated positions with C—H = 0.93 Å (aromatic) or 0.96 Å (methyl) and their coordinates and thermal parameters were constrained to ride on the carrier atom, with U_iso = 1.5U_eq(aromatic C) or 1.5U_eq(methyl C).

Table 2
Experimental details

Crystal data
Chemical formula	C₁₆H₁₁BrN₂O₄
M_r	375.18
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	296
a, b, c (Å)	8.4726 (3), 23.7748 (8), 8.0833 (3)
β (°)	111.6985 (17)
V (Å³)	1512.88 (9)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	2.74
Crystal size (mm)	0.35 × 0.20 × 0.09

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2010 )
T_min, T_max	0.428, 0.747
No. of measured, independent and observed [I > 2σ(I)] reflections	65083, 6269, 4739
R_int	0.037
(sin θ/λ)_max (Å⁻¹)	0.796

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.035, 0.089, 1.03
No. of reflections	6269
No. of parameters	216
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.59, −0.26
Computer programs: APEX2 and SAINT (Bruker, 2010), SHELXS97 and SHELXTL (Sheldrick 2008 ) and SHELXL2014 (Sheldrick, 2015 ).

Supporting information

CCDC reference: 1472611

Crystal structure: contains datablock I. DOI: 10.1107/S2056989016005715/zs2361sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S2056989016005715/zs2361Isup2.hkl

Supporting information file. DOI: 10.1107/S2056989016005715/zs2361Isup3.cml

checkCIF report

Chemical context top

Recently, a new class of molecules (hemibiquinones, HBQs) has been reported as potential molecular rectifiers (Meany et al., 2015). Biphenyl derivatives have garnered great attention as conductors of electricity (Venkataraman et al., 2006). The symmetric nature of the biphenyl and polyphenyl derivatives studied so far allows for reasonable conduction through the π orbitals. Biphenyl derivatives with one electron-rich and one electron-deficient ring may be able to preferentially bias the direction of electron flow through the molecule, thus acting as a molecular diode. The donor–bridge–acceptor model has long been accepted as a basis for the design of molecular rectifiers (Aviram & Ratner, 1974). The asymmetric biphenyl structure should allow for conductivity through each of the rings, while the dihedral angle between the two rings decreases orbital overlap and allows for partial isolation of the electron-rich donor and electron-poor acceptor moieties. The efficiency of conduction through a given molecule can be tuned depending on the torsion angle between the two rings.

Dicyano-functionalized hydroquinones are known for their ability to form hydrogen-bonded networks (Reddy et al., 1996) and charge-transfer complexes (Bock et al., 1996), sometimes both at once (Ghorai & Mani, 2014). They have also been used as rigid ligands in coordination polymers (Kuroda-Sowa et al., 1997). However, there are no crystal structures in which a dicyano-functionalized hydroquinone moiety has been appended to another aromatic ring. The present study affords an opportunity to investigate the mutual effects of these two functionalized ring systems on both the geometry of the molecule and its intermolecular interactions.

Structural commentary top

In the title compound (Fig. 1), the benzene rings are twisted out of a common plane, forming a dihedral angle of 53.59 (7)°, which appears to optimize the 2.7576 (18) Å O3—H···O2 intramolecular hydrogen bond (Table 1). The rings are essentially planar although the O3—H group, which participates in the intramolecular hydrogen bond, is displaced slightly out of the plane. Also, the rings are not co-axial with the C4—C7 bond that bridges them. This can be seen in torsion angles involving three carbon atoms from one ring and the bridging carbon atom from the other, which deviate from linearity by ca 5° [C2—C3—C4—C7 = 173.88 (14)°, C6—C5—C4—C7 = -175.45 (14)°, C4—C7—C8—C9 = 174.94 (13)°, C4—C7—C12—C11 = -175.62 (13)°]. This bending of the molecule about its long axis may also be due to hydrogen bonding as it causes the methoxy group to approach the OH group more closely. The aromatic C—C bonds of both rings have a narrow range of distances [from 1.387 (2) to 1.412 (2) Å]. The C—C, C—O, C—N, and C≡N distances for the molecule are similar to the corresponding distances in 2,3,5,6-tetracyanohydroquinone (Bock et al., 1993). The C—C bond distances around the bromodimethoxybenzene ring are close to those in the other hemibiquinone molecules containing this ring (Meany et al., 2015, 2016). The C9—C10 bond in (I) [1.408 (2) Å] is longer than the corresponding C1—C6 bond in BrHBQBr (1.334 Å; Meany et al., 2015). The stronger polarization of (I) relative to the starting material should weaken the bond through repulsive effects. The Br1—C1 bond is slightly shorter in (I) [1.885 (1) Å] compared to the starting material [1.898 (4) Å] as well, also suggesting decreased electron density on the dimethoxybenzene ring due to increased polarization. The calculated dipole (B3LYP-DGDZVP) of BrHBQBr is only 1.33 D, compared to 6.17 D for (I) .

As in the other reported hemibiquinone molecules (Meany et al., 2015), we seek to use and compare the inter-ring torsion angles in the crystals as a guide compared to gas-phase calculated values. The intramolecular hydrogen bond from the C8 phenol to the O2 methoxy group causes a greater torsion angle than that in the starting HBQ (Meany et al., 2015). In (I), the C5—C4—C7—C8 torsion angle is -126.5 (2)°, compared to -110.9 (5)° in HBQ. DFT (B3LYP-DGDZVP) calculations performed on the target molecule in the gas phase predict an angle of 48.85°. This significant discrepancy is due to packing interactions in the solid phase as well as the additional hydrogen bond. The hydrogen bond is indicated in Fig. 1, while the relative orientations of the rings can be seen in Fig. 2.

The O3—H···O2 intramolecular hydrogen bond points toward the non-bonded electrons on O2 with a total bond angle of 152 (3)°. As a result of the influence of other short contacts and supramolecular interactions (see below), the phenolic C—O—H bond angles deviate when compared to the methoxy C—O—C bond angles: C8—O3—H is 108 (2)°, C11—O4—H is 112.3 (2)°, C3—O2—C14 is 117.9 (1)°, and C6—O1—C13 is 117.2 (1)°. As in other structures, the methoxy groups are aligned mostly in-plane with the benzene ring, C5— C6—O1—C13 being bent out of plane by -4.5 (2)° and C2—C3—O2—C14 bent out of plane by -1.3 (2)°. The C12—C11—O4—H phenol group is also nearly planar, being bent out of plane by 1.3°. However, the hydrogen-bonded phenol is unsurprisingly bent out of plane, C7—C8—O3—H = 38 (2)°. The methoxy methyl groups point away from the sterically restricting groups ortho to these positions.

Supramolecular features top

Each molecule makes short (less than the sum of the van der Waals radii) contacts to six neighboring molecules (Fig. 3). As in previously reported HBQ structures, rings of like identity are all aligned in parallel planes. All short contacts are associated with Lewis acid–base interactions of some kind, and for each interaction there is one neighboring molecule that acts as a donor and second that acts as an acceptor. Two central molecules in the unit cell stack antiparallel to one another, the quinone rings shifted off-center from one another in the a-axis direction. Both nitrile groups are involved in intermolecular hydrogen-bonding interactions, the first one (O4—H···N1) strong , the second one (C2—H···N2) weaker but still highly directional. For details, see Table 1. These interactions link molecules along the crystallographic a- and b-axis directions, respectively, forming sheets parallel to (010) (Fig. 4). The quinone rings are aligned parallel to the bc plane diagonal.

The remaining two molecules in the unit cell are oriented orthogonally to the central molecules. These molecules are antiparallel to each other, where the dimethoxybenzene rings stack with those of the central pair. Slightly repulsive π-interactions between molecules along b and stacking along c can be seen in Fig. 5. Intercentroid distances for the rings are longer than expected for close π interactions at 4.107 (1) Å. However, since the rings are slightly offset from one another, this is not the correct centroid to use. Instead, a close 3.598 (1) Å π-interaction between two intermolecular C9—C10 centroids exists. A centroid calculated for the C7—C8—C9—C11—C12 ring sits 3.574 (1) Å from a centroid for N1—C15—C9—C10—C16—N2, which may be explained by the electron-donating character of the hydroquinone as compared to the dinitrile substituents. The planes of the dimethoxybenzene rings are oriented parallel to the short diagonal of the ac plane.

Synthesis and crystallization top

Refinement top

Structure description top

Recently, a new class of molecules (hemibiquinones, HBQs) has been reported as potential molecular rectifiers (Meany et al., 2015). Biphenyl derivatives have garnered great attention as conductors of electricity (Venkataraman et al., 2006). The symmetric nature of the biphenyl and polyphenyl derivatives studied so far allows for reasonable conduction through the π orbitals. Biphenyl derivatives with one electron-rich and one electron-deficient ring may be able to preferentially bias the direction of electron flow through the molecule, thus acting as a molecular diode. The donor–bridge–acceptor model has long been accepted as a basis for the design of molecular rectifiers (Aviram & Ratner, 1974). The asymmetric biphenyl structure should allow for conductivity through each of the rings, while the dihedral angle between the two rings decreases orbital overlap and allows for partial isolation of the electron-rich donor and electron-poor acceptor moieties. The efficiency of conduction through a given molecule can be tuned depending on the torsion angle between the two rings.

Dicyano-functionalized hydroquinones are known for their ability to form hydrogen-bonded networks (Reddy et al., 1996) and charge-transfer complexes (Bock et al., 1996), sometimes both at once (Ghorai & Mani, 2014). They have also been used as rigid ligands in coordination polymers (Kuroda-Sowa et al., 1997). However, there are no crystal structures in which a dicyano-functionalized hydroquinone moiety has been appended to another aromatic ring. The present study affords an opportunity to investigate the mutual effects of these two functionalized ring systems on both the geometry of the molecule and its intermolecular interactions.

As in the other reported hemibiquinone molecules (Meany et al., 2015), we seek to use and compare the inter-ring torsion angles in the crystals as a guide compared to gas-phase calculated values. The intramolecular hydrogen bond from the C8 phenol to the O2 methoxy group causes a greater torsion angle than that in the starting HBQ (Meany et al., 2015). In (I), the C5—C4—C7—C8 torsion angle is -126.5 (2)°, compared to -110.9 (5)° in HBQ. DFT (B3LYP-DGDZVP) calculations performed on the target molecule in the gas phase predict an angle of 48.85°. This significant discrepancy is due to packing interactions in the solid phase as well as the additional hydrogen bond. The hydrogen bond is indicated in Fig. 1, while the relative orientations of the rings can be seen in Fig. 2.

Each molecule makes short (less than the sum of the van der Waals radii) contacts to six neighboring molecules (Fig. 3). As in previously reported HBQ structures, rings of like identity are all aligned in parallel planes. All short contacts are associated with Lewis acid–base interactions of some kind, and for each interaction there is one neighboring molecule that acts as a donor and second that acts as an acceptor. Two central molecules in the unit cell stack antiparallel to one another, the quinone rings shifted off-center from one another in the a-axis direction. Both nitrile groups are involved in intermolecular hydrogen-bonding interactions, the first one (O4—H···N1) strong , the second one (C2—H···N2) weaker but still highly directional. For details, see Table 1. These interactions link molecules along the crystallographic a- and b-axis directions, respectively, forming sheets parallel to (010) (Fig. 4). The quinone rings are aligned parallel to the bc plane diagonal.

The remaining two molecules in the unit cell are oriented orthogonally to the central molecules. These molecules are antiparallel to each other, where the dimethoxybenzene rings stack with those of the central pair. Slightly repulsive π-interactions between molecules along b and stacking along c can be seen in Fig. 5. Intercentroid distances for the rings are longer than expected for close π interactions at 4.107 (1) Å. However, since the rings are slightly offset from one another, this is not the correct centroid to use. Instead, a close 3.598 (1) Å π-interaction between two intermolecular C9—C10 centroids exists. A centroid calculated for the C7—C8—C9—C11—C12 ring sits 3.574 (1) Å from a centroid for N1—C15—C9—C10—C16—N2, which may be explained by the electron-donating character of the hydroquinone as compared to the dinitrile substituents. The planes of the dimethoxybenzene rings are oriented parallel to the short diagonal of the ac plane.

Synthesis and crystallization top

Refinement details top

Computing details top

Data collection: APEX2 (Bruker, 2010); cell refinement: SAINT (Bruker, 2010); data reduction: SAINT (Bruker, 2010); program(s) used to solve structure: SHELXS97 (Sheldrick 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of (I), showing the atom-numbering scheme. Displacement ellipsoids are displayed at the 50% probability level. The intramolecular O3—H···O2 hydrogen bond is shown as a dashed line.
	Fig. 2. Ball-and-stick plot of (I), viewed down the C4—C7 bond.
	Fig. 3. Short (less than the sum of the van der Waals radii) contact environment around [BrHBQH₂(CN)₂]. Dashed green lines indicate short contacts. Axes are color coded: red = a axis, green = b axis and blue = c axis.
	Fig. 4. Hydrogen-bonded sheets along ab. Dashed green lines indicate short contacts. Axes are color coded: red = a axis, green = b axis and blue = c axis.
	Fig. 5. Unit-cell packing of (I), viewed along the a axis. Short contacts show the long ring stacking along the c axis.

4'-Bromo-2,5-dihydroxy-2',5'-dimethoxy-[1,1'-biphenyl]-3,4-dicarbonitrile top

Crystal data top

C₁₆H₁₁BrN₂O₄	F(000) = 752
M_r = 375.18	D_x = 1.647 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 8.4726 (3) Å	Cell parameters from 9370 reflections
b = 23.7748 (8) Å	θ = 2.6–29.9°
c = 8.0833 (3) Å	µ = 2.74 mm⁻¹
β = 111.6985 (17)°	T = 296 K
V = 1512.88 (9) Å³	Tablet, yellow-orange
Z = 4	0.35 × 0.20 × 0.09 mm

Data collection top

Bruker APEXII CCD diffractometer	4739 reflections with I > 2σ(I)
φ and ω scans	R_int = 0.037
Absorption correction: multi-scan (SADABS; Bruker, 2010)	θ_max = 34.5°, θ_min = 1.7°
T_min = 0.428, T_max = 0.747	h = −13→13
65083 measured reflections	k = −37→37
6269 independent reflections	l = −12→12

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.035	Hydrogen site location: mixed
wR(F²) = 0.089	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ²(F_o²) + (0.0431P)² + 0.4609P] where P = (F_o² + 2F_c²)/3
6269 reflections	(Δ/σ)_max = 0.001
216 parameters	Δρ_max = 0.59 e Å⁻³
0 restraints	Δρ_min = −0.26 e Å⁻³

Crystal data top

C₁₆H₁₁BrN₂O₄	V = 1512.88 (9) Å³
M_r = 375.18	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 8.4726 (3) Å	µ = 2.74 mm⁻¹
b = 23.7748 (8) Å	T = 296 K
c = 8.0833 (3) Å	0.35 × 0.20 × 0.09 mm
β = 111.6985 (17)°

Data collection top

Bruker APEXII CCD diffractometer	6269 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2010)	4739 reflections with I > 2σ(I)
T_min = 0.428, T_max = 0.747	R_int = 0.037
65083 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.035	0 restraints
wR(F²) = 0.089	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	Δρ_max = 0.59 e Å⁻³
6269 reflections	Δρ_min = −0.26 e Å⁻³
216 parameters

Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Br1	0.00177 (2)	0.18718 (2)	0.27906 (3)	0.03808 (6)
O1	0.09291 (15)	0.30658 (4)	0.37344 (17)	0.0372 (3)
O2	−0.52102 (14)	0.29007 (5)	−0.19615 (17)	0.0400 (3)
O3	−0.65570 (14)	0.38022 (5)	−0.07840 (19)	0.0393 (3)
H3A	−0.639 (3)	0.3515 (11)	−0.093 (3)	0.059*
O4	−0.25442 (16)	0.52226 (5)	−0.2911 (2)	0.0502 (4)
H4A	−0.163 (3)	0.5103 (10)	−0.276 (3)	0.050*
N1	−0.92239 (18)	0.49008 (7)	−0.2525 (3)	0.0524 (4)
N2	−0.6248 (3)	0.59864 (7)	−0.3963 (3)	0.0594 (5)
C1	−0.12247 (17)	0.25158 (6)	0.1689 (2)	0.0269 (3)
C2	−0.27623 (17)	0.24472 (6)	0.0277 (2)	0.0290 (3)
H2A	−0.3187	0.2089	−0.0098	0.035*
C3	−0.36583 (17)	0.29233 (6)	−0.0569 (2)	0.0277 (3)
C4	−0.30049 (16)	0.34595 (5)	−0.00356 (19)	0.0258 (2)
C5	−0.14639 (17)	0.35126 (6)	0.1413 (2)	0.0276 (3)
H5A	−0.1032	0.3870	0.1789	0.033*
C6	−0.05661 (18)	0.30449 (6)	0.2301 (2)	0.0271 (3)
C7	−0.38125 (16)	0.39804 (5)	−0.09918 (19)	0.0258 (2)
C8	−0.55087 (16)	0.41297 (6)	−0.1289 (2)	0.0269 (3)
C9	−0.61363 (16)	0.46445 (6)	−0.20684 (19)	0.0270 (3)
C10	−0.51175 (16)	0.50206 (6)	−0.2583 (2)	0.0283 (3)
C11	−0.34649 (17)	0.48643 (6)	−0.2341 (2)	0.0312 (3)
C12	−0.28382 (17)	0.43499 (6)	−0.1544 (2)	0.0300 (3)
H12A	−0.1728	0.4251	−0.1377	0.036*
C13	0.1665 (2)	0.36036 (8)	0.4267 (3)	0.0523 (5)
H13A	0.2725	0.3563	0.5253	0.078*
H13B	0.0908	0.3832	0.4618	0.078*
H13C	0.1860	0.3780	0.3291	0.078*
C14	−0.5909 (2)	0.23599 (7)	−0.2582 (3)	0.0411 (4)
H14A	−0.6967	0.2403	−0.3568	0.062*
H14B	−0.6098	0.2161	−0.1638	0.062*
H14C	−0.5131	0.2151	−0.2957	0.062*
C15	−0.78630 (18)	0.47882 (7)	−0.2331 (2)	0.0346 (3)
C16	−0.5754 (2)	0.55568 (7)	−0.3358 (2)	0.0368 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.03661 (8)	0.02562 (8)	0.05028 (11)	0.00760 (5)	0.01403 (7)	0.01143 (6)
O1	0.0332 (5)	0.0295 (5)	0.0380 (6)	0.0005 (4)	0.0002 (5)	0.0032 (4)
O2	0.0303 (5)	0.0276 (5)	0.0480 (7)	−0.0015 (4)	−0.0019 (5)	−0.0029 (5)
O3	0.0287 (5)	0.0312 (5)	0.0611 (8)	−0.0015 (4)	0.0201 (5)	0.0066 (5)
O4	0.0361 (6)	0.0334 (6)	0.0905 (11)	0.0093 (5)	0.0344 (7)	0.0259 (6)
N1	0.0283 (7)	0.0508 (9)	0.0779 (12)	0.0084 (6)	0.0192 (7)	0.0051 (8)
N2	0.0674 (11)	0.0381 (8)	0.0724 (12)	0.0203 (8)	0.0255 (10)	0.0161 (8)
C1	0.0264 (6)	0.0219 (6)	0.0334 (7)	0.0039 (4)	0.0122 (5)	0.0046 (5)
C2	0.0286 (6)	0.0202 (6)	0.0380 (8)	0.0004 (4)	0.0120 (6)	0.0003 (5)
C3	0.0233 (5)	0.0233 (6)	0.0342 (7)	0.0003 (4)	0.0079 (5)	0.0003 (5)
C4	0.0238 (5)	0.0205 (5)	0.0325 (7)	0.0019 (4)	0.0098 (5)	0.0025 (5)
C5	0.0261 (6)	0.0208 (5)	0.0341 (7)	0.0007 (4)	0.0090 (5)	0.0009 (5)
C6	0.0254 (5)	0.0251 (6)	0.0296 (7)	0.0018 (5)	0.0088 (5)	0.0024 (5)
C7	0.0223 (5)	0.0206 (5)	0.0322 (7)	0.0021 (4)	0.0073 (5)	0.0005 (5)
C8	0.0211 (5)	0.0249 (6)	0.0330 (7)	−0.0002 (4)	0.0082 (5)	−0.0005 (5)
C9	0.0208 (5)	0.0251 (6)	0.0330 (7)	0.0031 (4)	0.0073 (5)	−0.0011 (5)
C10	0.0259 (6)	0.0229 (6)	0.0354 (8)	0.0052 (4)	0.0105 (5)	0.0035 (5)
C11	0.0262 (6)	0.0232 (6)	0.0462 (9)	0.0034 (5)	0.0158 (6)	0.0067 (6)
C12	0.0226 (5)	0.0243 (6)	0.0433 (8)	0.0044 (4)	0.0122 (5)	0.0060 (5)
C13	0.0467 (10)	0.0336 (8)	0.0546 (11)	−0.0069 (7)	−0.0069 (8)	−0.0022 (8)
C14	0.0353 (7)	0.0336 (8)	0.0483 (10)	−0.0086 (6)	0.0083 (7)	−0.0100 (7)
C15	0.0262 (6)	0.0302 (7)	0.0455 (9)	0.0038 (5)	0.0109 (6)	−0.0008 (6)
C16	0.0364 (8)	0.0297 (7)	0.0453 (9)	0.0088 (6)	0.0165 (7)	0.0063 (6)

Geometric parameters (Å, º) top

Br1—C1	1.8848 (13)	C5—C6	1.3878 (19)
O1—C6	1.3655 (18)	C5—H5A	0.9300
O1—C13	1.418 (2)	C7—C12	1.3876 (19)
O2—C3	1.3799 (17)	C7—C8	1.4120 (18)
O2—C14	1.4266 (19)	C8—C9	1.3892 (19)
O3—C8	1.3528 (17)	C9—C10	1.408 (2)
O3—H3A	0.72 (3)	C9—C15	1.4396 (19)
O4—C11	1.3464 (18)	C10—C11	1.3907 (18)
O4—H4A	0.79 (2)	C10—C16	1.434 (2)
N1—C15	1.137 (2)	C11—C12	1.3927 (19)
N2—C16	1.143 (2)	C12—H12A	0.9300
C1—C2	1.388 (2)	C13—H13A	0.9600
C1—C6	1.3909 (19)	C13—H13B	0.9600
C2—C3	1.3933 (19)	C13—H13C	0.9600
C2—H2A	0.9300	C14—H14A	0.9600
C3—C4	1.3933 (19)	C14—H14B	0.9600
C4—C5	1.4004 (19)	C14—H14C	0.9600
C4—C7	1.4860 (18)

C6—O1—C13	117.15 (12)	C9—C8—C7	119.57 (12)
C3—O2—C14	117.91 (12)	C8—C9—C10	121.32 (12)
C8—O3—H3A	108 (2)	C8—C9—C15	118.27 (13)
C11—O4—H4A	112.3 (17)	C10—C9—C15	120.41 (13)
C2—C1—C6	121.99 (12)	C11—C10—C9	118.94 (12)
C2—C1—Br1	118.91 (10)	C11—C10—C16	119.68 (13)
C6—C1—Br1	119.09 (10)	C9—C10—C16	121.38 (12)
C1—C2—C3	118.92 (12)	O4—C11—C10	117.60 (13)
C1—C2—H2A	120.5	O4—C11—C12	122.95 (12)
C3—C2—H2A	120.5	C10—C11—C12	119.45 (13)
O2—C3—C4	115.96 (12)	C7—C12—C11	122.30 (12)
O2—C3—C2	123.42 (13)	C7—C12—H12A	118.8
C4—C3—C2	120.62 (12)	C11—C12—H12A	118.8
C3—C4—C5	118.83 (12)	O1—C13—H13A	109.5
C3—C4—C7	123.21 (12)	O1—C13—H13B	109.5
C5—C4—C7	117.87 (12)	H13A—C13—H13B	109.5
C6—C5—C4	121.56 (13)	O1—C13—H13C	109.5
C6—C5—H5A	119.2	H13A—C13—H13C	109.5
C4—C5—H5A	119.2	H13B—C13—H13C	109.5
O1—C6—C5	124.67 (12)	O2—C14—H14A	109.5
O1—C6—C1	117.32 (12)	O2—C14—H14B	109.5
C5—C6—C1	118.01 (13)	H14A—C14—H14B	109.5
C12—C7—C8	118.37 (12)	O2—C14—H14C	109.5
C12—C7—C4	118.74 (11)	H14A—C14—H14C	109.5
C8—C7—C4	122.82 (12)	H14B—C14—H14C	109.5
O3—C8—C9	117.39 (12)	N1—C15—C9	179.5 (2)
O3—C8—C7	122.99 (13)	N2—C16—C10	179.4 (2)

C13—O1—C6—C1	175.14 (15)	C4—C5—C6—O1	−179.10 (15)
C13—O1—C6—C5	−4.5 (2)	C4—C5—C6—C1	1.2 (2)
C14—O2—C3—C2	−1.3 (2)	C4—C7—C8—O3	−2.4 (2)
C14—O2—C3—C4	178.48 (15)	C4—C7—C8—C9	174.94 (13)
Br1—C1—C2—C3	−178.26 (12)	C12—C7—C8—O3	−179.24 (14)
C6—C1—C2—C3	1.0 (2)	C12—C7—C8—C9	−1.9 (2)
Br1—C1—C6—O1	−2.8 (2)	C4—C7—C12—C11	−175.62 (13)
Br1—C1—C6—C5	176.93 (12)	C8—C7—C12—C11	1.4 (2)
C2—C1—C6—O1	177.95 (14)	O3—C8—C9—C10	177.94 (14)
C2—C1—C6—C5	−2.4 (2)	O3—C8—C9—C15	−1.7 (2)
C1—C2—C3—O2	−178.78 (14)	C7—C8—C9—C10	0.5 (2)
C1—C2—C3—C4	1.5 (2)	C7—C8—C9—C15	−179.13 (13)
O2—C3—C4—C5	177.70 (14)	C8—C9—C10—C11	1.6 (2)
O2—C3—C4—C7	−5.9 (2)	C8—C9—C10—C16	−178.84 (14)
C2—C3—C4—C5	−2.6 (2)	C15—C9—C10—C11	−178.81 (14)
C2—C3—C4—C7	173.88 (14)	C15—C9—C10—C16	0.8 (2)
C3—C4—C5—C6	1.2 (2)	C9—C10—C11—O4	177.38 (14)
C7—C4—C5—C6	−175.45 (14)	C9—C10—C11—C12	−2.1 (2)
C3—C4—C7—C8	57.1 (2)	C16—C10—C11—O4	−2.2 (2)
C3—C4—C7—C12	−126.09 (16)	C16—C10—C11—C12	178.27 (14)
C5—C4—C7—C8	−126.50 (16)	O4—C11—C12—C7	−178.82 (14)
C5—C4—C7—C12	50.37 (19)	C10—C11—C12—C7	0.7 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···O2	0.72 (3)	2.11 (3)	2.7576 (18)	152 (3)
O4—H4A···N1ⁱ	0.79 (2)	2.03 (2)	2.8189 (18)	172 (2)
C2—H2A···N2ⁱⁱ	0.93	2.72	3.638 (2)	168

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···O2	0.72 (3)	2.11 (3)	2.7576 (18)	152 (3)
O4—H4A···N1ⁱ	0.79 (2)	2.03 (2)	2.8189 (18)	172 (2)
C2—H2A···N2ⁱⁱ	0.93	2.72	3.638 (2)	168.2

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

Experimental details

Crystal data
Chemical formula	C₁₆H₁₁BrN₂O₄
M_r	375.18
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	296
a, b, c (Å)	8.4726 (3), 23.7748 (8), 8.0833 (3)
β (°)	111.6985 (17)
V (Å³)	1512.88 (9)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	2.74
Crystal size (mm)	0.35 × 0.20 × 0.09

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2010)
T_min, T_max	0.428, 0.747
No. of measured, independent and observed [I > 2σ(I)] reflections	65083, 6269, 4739
R_int	0.037
(sin θ/λ)_max (Å⁻¹)	0.796

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.035, 0.089, 1.03
No. of reflections	6269
No. of parameters	216
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.59, −0.26

Computer programs: APEX2 (Bruker, 2010), SAINT (Bruker, 2010), SHELXS97 (Sheldrick 2008), SHELXL2014 (Sheldrick, 2015), SHELXTL (Sheldrick, 2008).

Acknowledgements

This research was supported by the National Science Foundation (CHE-08–48206). One of us (JEM) is grateful to the Department of Education's Graduate Assistance in Areas of National Need (GAANN) Program for fellowship support. We appreciate the assistance of Professor David Dixon and Dr Edward Garner in performing DFT calculations.

References

Aviram, A. & Ratner, M. A. (1974). Chem. Phys. Lett. 29, 277–283. CrossRef CAS Web of Science Google Scholar
Bock, H., Seitz, W., Havlas, Z. & Bats, J. W. (1993). Angew. Chem. Int. Ed. Engl. 32, 411–414. CSD CrossRef Web of Science Google Scholar
Bock, H., Seitz, W., Sievert, M., Kleine, M. & Bats, J. W. (1996). Angew. Chem. Int. Ed. Engl. 35, 2244–2246. CSD CrossRef CAS Web of Science Google Scholar
Bruker (2010). APEX2, SAINT and SADABS. Bruker AXS, Inc., Madison, Wisconsin, USA. Google Scholar
Ghorai, D. & Mani, G. (2014). RSC Adv. 4, 45603–45611. Web of Science CSD CrossRef CAS Google Scholar
Kuroda-Sowa, T., Horino, T., Yamamoto, M., Ohno, Y., Maekawa, M. & Munakata, M. (1997). Inorg. Chem. 36, 6382–6389. Web of Science CSD CrossRef CAS Google Scholar
Meany, J. E., Gerlach, D. L., Papish, E. T. & Woski, S. A. (2016). Acta Cryst. E72, 600–603. CSD CrossRef IUCr Journals Google Scholar
Meany, J. E., Kelley, S. P., Metzger, R. M., Rogers, R. D. & Woski, S. A. (2015). Acta Cryst. E71, 1454–1456. Web of Science CSD CrossRef IUCr Journals Google Scholar
Reddy, D. S., Ovchinnikov, Y. E., Shishkin, O. V., Struchkov, Y. T. & Desiraju, G. T. (1996). J. Am. Chem. Soc. 118, 4085–4089. CSD CrossRef CAS Web of Science Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Sheldrick, G. M. (2015). Acta Cryst. C71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Venkataraman, L., Klare, J. E., Nuckolls, C., Hybertsen, M. S. & Steigerwald, M. L. (2006). Nature, 442, 904–907. Web of Science CrossRef PubMed CAS Google Scholar

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Volume 72| Part 5| May 2016| Pages 667-670

doi:10.1107/S2056989016005715

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research communications\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Crystal structure of 4′-bromo-2,5-dihy­dr­oxy-2′,5′-dimeth­­oxy-[1,1′-biphen­yl]-3,4-dicarbo­nitrile

1. Chemical context

2. Structural commentary

3. Supra­molecular features

4. Synthesis and crystallization

5. Refinement

Supporting information

Acknowledgements

References

research communications

Crystal structure of 4′-bromo-2,5-dihydroxy-2′,5′-dimethoxy-[1,1′-biphenyl]-3,4-dicarbonitrile

3. Supramolecular features