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CHEMISTRY
ISSN: 2053-2296

4-[Bis(4-hydr­­oxy-3,5-di­methyl­phenyl)­methyl]pyridinium chloride and bromide

aDepartment of Chemistry, Indian Institute of Technology, Guwahati 781 039, Assam, India, and bDepartment of Chemistry, University of Durham, South Road, Durham DH1 3LE, England
*Correspondence e-mail: a.s.batsanov@durham.ac.uk

(Received 18 January 2005; accepted 15 March 2005; online 30 April 2005)

The isostructural title salts, 4-[bis­(4-hydroxy-3,5-dimethyl­phenyl)­methyl]­pyridinium chloride and bromide, C22H24NO2+·Cl and C22H24NO2+·Br, exhibit extended hydrogen-bonded ribbons in the solid state. The halide ions form hydrogen bonds to the pyridinium NH+ group and to the phenol OH groups of the cation. These bonds are coplanar to within 0.1 Å and form a T configuration at the anion.

Comment

The coordination chemistry of anions is a fast-growing area of supramolecular chemistry (see, for example, Bianchi et al., 1997[Bianchi, A., Bowman-James, K. & Garcia-España, E. (1997). Editors. Supramolecular Chemistry of Anions. New York: Wiley-VCH.]; Schmidtchen & Berger, 1997[Schmidtchen, F. P. & Berger, M. (1997). Chem. Rev. 97, 1609-1646.]), both on account of the importance of anion binding, recognition and transport in many biochemical processes (Lehn, 1995[Lehn, J. M. (1995). Supramolecular Chemistry: Concepts and Perspectives. Weinheim: VCH.]; Beer, 1996[Beer, P. D. (1996). J. Chem. Soc. Chem. Commun. pp. 689-696.]; Pajewski et al., 2004[Pajewski, R., Ferdani, R., Schlesinger, P. H. & Gokel, G. W. (2004). Chem. Commun. pp. 160-161.], and references therein) and because anions can be

[Scheme 1]
used to direct the self-assembly of organic (and organo­metallic) mol­ecules in desired ways (Gale, 2000[Gale, P. A. (2000). Coord. Chem. Rev. 199, 181-233.], 2001[Gale, P. A. (2001). Coord. Chem. Rev. 213, 79-128.]; Sessler et al., 2003[Sessler, J. L. Camiolo, S. & Gale, P. A. (2003). Coord. Chem. Rev. 240, 17-55.]). Thus, the Cl anion has been successfully used to assemble double-helical motifs of various mol­ecules containing aromatic groups, with π-stacking within the helices (Hasenknopf et al., 1996[Hasenknopf, B., Lehn, J. M., Kniesel, B., Baum, G. & Fenske, D. (1996). Angew. Chem. Int. Ed. Engl. 35, 1838-1840.], 1997[Hasenknopf, B., Lehn, J. M., Boumediene, N., Dupont-Gervais, A., Van Dorsselar, A., Kniesel, B. & Fenske, D. (1997). J. Am. Chem. Soc. 119, 10956-10962.]). Indeed, halide anions can be particularly useful for such applications because of the high flexibility of their coordination (Ilioudis et al., 2000[Ilioudis, C. A., Hancock, K. S. B., Georganopoulou, D. G. & Steed, J. W. (2000). New J. Chem. 24, 787-798.]). In the present work, we have investigated the effects of Cl and Br ions on the assembly of 4-[bis&4-hydroxy-shy;(4-hydroxy-3,5-dimethyl­phenyl)­methyl]pyridine, L, a mol­ecule with a relatively rigid tripodal framework. To our knowledge, neither this mol­ecule nor any other with one pyridyl and two 4-hydroxyphenyl groups linked through a single C atom has been structurally characterized to date. Meanwhile, related ArCH(C6H4OH-p)2 (e.g. with Ar = C6H4Br-p) compounds have been used as ligands to obtain topologically chiral [2]catenane complexes of gold(I), whereby the unsymmetrical ArCH `hinge group' plays a crucial role in imposing chirality (McArdle et al., 2002[McArdle, C. P., Van, S., Jennings, M. C. & Puddephatt, R. J. (2002). J. Am. Chem. Soc. 124, 3959-3965.]).

Originally, we intended to prepare a copper(II) complex of L to serve as a building block for the construction of a supermolecule. However, crystallization from an aqueous solution containing equivalent quantities of HCl, L and CuCl2·2H2O unexpectedly yielded LH+·Cl, (I)[link]. This compound and its analogue LH+·Br, (II)[link], were also formed from an acidic solution of L and HCl (or HBr) in the presence of catalytic quantities of CuCl2·2H2O, but in the complete absence of the latter we could not obtain any crystals of the salts.

The crystals of (I)[link] and (II)[link] are isomorphous. The asymmetric unit comprises one halide anion and one LH+ cation (with N1 protonated), which adopts practically the same propeller-like conformation in both crystals; the pyridine ring and benzene rings bearing atoms O1 and O2 (Fig. 1[link]) are inclined to the C4/C14/C24 plane in the same sense by 53.9 (1), 42.6 (1) and 41.5 (1)°, respectively, in (I)[link] and by 55.0 (1), 39.7 (1) and 41.4 (1)°, respectively, in (II)[link].

The asymmetric unit contains three H atoms (two hydroxyl and one pyridinium) capable of forming strong hydrogen bonds, and three potential acceptors, viz. two O atoms and the halide anion. In fact, only the anion acts as the acceptor of all three such bonds (Table 5[link]), probably because the competitiveness of the O atoms as acceptors is severely diminished by the masking effect of the adjacent methyl groups. The anion and the three bonded H atoms are coplanar to within 0.1 Å. The configuration can be described as T-shaped rather than trigonal (Fig. 2[link]), which is relatively rare but not unknown (Ilioudis et al., 2000[Ilioudis, C. A., Hancock, K. S. B., Georganopoulou, D. G. & Steed, J. W. (2000). New J. Chem. 24, 787-798.]). Indeed, halide anions are known to behave as `spherical' acceptors without any clearly favoured coordination geometry, although some preference towards quasi-tetra­hedral and trigonal configurations can be discerned (Ilioudis et al., 2000[Ilioudis, C. A., Hancock, K. S. B., Georganopoulou, D. G. & Steed, J. W. (2000). New J. Chem. 24, 787-798.]).

These three strong hydrogen bonds link the cations into ribbons running parallel to the crystallographic b axis (Fig. 2[link]). Besides these, the anion participates in three weak inter­actions (Table 5[link]) with aromatic and methyl H atoms, with each of the six contacts involving a different cation. It is noteworthy that strong bonds in (II)[link] are longer than those in (I)[link], roughly in line with the increase of the ionic radius of Br (1.96 Å; Shannon & Prewitt, 1969[Shannon, R. D. & Prewitt, C. T. (1969). Acta Cryst. B25, 925-946.]) compared with Cl (1.81 Å), but the weak bonds lengthen much less or even contract on going from (I)[link] to (II)[link]. The difference can be explained by the higher polarizability of the Br anion and hence higher (C)H⋯X dispersion inter­actions in (II)[link], while this difference is less relevant for the strong hydrogen bonds, which have larger contributions of (time-independent) ion–dipole inter­actions. The weak hydrogen bonds are roughly normal to the T-plane of the strong hydrogen bonds, while the wide angle φ1 is occupied by pyridine atom C2 of another cation, generated by inversion at (1 − x, 2 − y, −z). The corresponding distances [Cl⋯C2 = 3.382 (2) Å and Br⋯C2 = 3.458 (1) Å] are both shorter than the sums of the van der Waals radii (3.53 and 3.65 Å, respectively; Rowland & Taylor, 1996[Rowland, R. S. & Taylor, R. (1996). J. Phys. Chem. 100, 7384-7391.]).

Thus, through this system of hydrogen bonds, the halide anions are decisive in directing the packing of the LH+ cations. However, the resulting structure is ribbon-like rather than helical. Substitution of a Br anion for Cl affects different types of hydrogen bonds selectively. Also noteworthy is the ability of copper(II) chloride to facilitate the crystallization of (I)[link] and (II)[link] without itself being incorporated into the structure. This effect may be useful as a method for controlling mol­ecular self-assembly. Therefore, we intend a further study of its mechanism and possible applications.

[Figure 1]
Figure 1
The cations and anions in the structures of (a) (I)[link] and (b) (II)[link], showing the atomic numbering schemes. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2]
Figure 2
The system of strong hydrogen bonds in structures (I)[link] (X = Cl) and (II)[link] (X = Br). The H⋯X⋯H angles are φ1 = 170°, φ2 = 84° and φ3 = 104° in (I)[link], and φ1 = 73°, φ2 = 82° and φ3 = 105° in (II)[link]; s.u. values are ∼1°. The symmetry codes are as given in the tables.

Experimental

Compound L was synthesized by condensation of 2,6-dimethyl-phenol with pyridine-4-carbaldehyde. Specifically, pyridine-4-carbaldehyde (0.534 g, 5.0 mmol) and 2,6-dimethyl­phenol (1.221 g, 10 mmol) were dissolved in 1 M sulfuric acid (1.4 ml) mixed with methanol (10 ml). Trifloroacetic acid (1 ml) was then added. The mixture was heated at 353 K for 8 h, after which the solvents were removed under vacuum. The residue was dissolved in water (15 ml), extracted with ethyl acetate (15 ml) and dried over anhydrous Na2SO4. Removal of the solvents and subsequent column chromatography (silica gel 60–120 mesh; hexanes/ethyl acetate, 4:1) gave L as a white solid (yield: 1.43 g, 86%; m.p. 478 K). IR (KBr, ν, cm−1): 3385 (s), 3083 (s), 2914 (w), 2079 (w), 1634 (s), 1485 (s), 1147 (s), 1004 (s); 1H NMR (400 MHz, DMSO-d6,): δ 2.18 (s, 12H), 3.70 (s, 2H), 5.43 (s, 1H), 6.60 (s, 4H), 7.6 (d, 2H, J = 6.4 Hz), 6.7 (d, 2H, J = 6.4 Hz); 13C NMR (100 MHz, DMSO-d6): δ 17.4, 55.68, 125.18, 127.78, 129.25, 131.46, 141.63, 152.81, 166.53. Slow evaporation of a solution of L (0.332 g, 1 mmol) and HCl (0.3 ml, 11.5 M) in methanol in the presence of CuCl2·2H2O (0.085 g, 5 mol%) gave (I)[link] as a pale-yellow precipitate, which was recrystallized from methanol (m.p. 487 K). IR (KBr, ν, cm−1): 3375 (s), 2786 (s), 2034 (s), 1629 (s), 1481 (s), 1317 (s), 1194 (s), 1024 (w). Slow evaporation of a solution of L (0.333 g, 1 mmol) in methanol containing HBr (0.5 ml, 60%) and cupric bromide (0.012 g, 5 mol%) gave (II)[link] as pale-orange crystals (m.p. 492 K). IR (KBr, ν, cm−1): 3334 (s), 3228 (w), 2930 (s), 2022 (s), 1775 (s), 1629 (s), 1492 (s), 1190 (s), 1134 (w).

Compound (I)[link]

Crystal data
  • C22H24NO2+·Cl

  • Mr = 369.87

  • Monoclinic, P 21 /n

  • a = 8.6590 (2) Å

  • b = 14.3920 (17) Å

  • c = 15.7057 (12) Å

  • β = 102.519 (14)°

  • V = 1910.7 (3) Å3

  • Z = 4

  • Dx = 1.286 Mg m−3

  • Mo Kα radiation

  • Cell parameters from 4680 reflections

  • θ = 2.4–29.7°

  • μ = 0.22 mm−1

  • T = 120 (2) K

  • Tetragonal prism, yellow

  • 0.26 × 0.15 × 0.09 mm

Data collection
  • Bruker SMART 6000 CCD area-detector diffractometer

  • ω scans

  • Absorption correction: integration(XPREP in SHELXTL; Bruker, 2001[Bruker (2001). SMART (Version 5.625), SAINT (Version 6.02a) and SHELXTL (Version 6.12). Bruker AXS Inc., Madison, Wisconsin, USA.])Tmin = 0.953, Tmax = 0.984

  • 21 158 measured reflections

  • 4383 independent reflections

  • 3330 reflections with I > 2σ(I)

  • Rint = 0.058

  • θmax = 27.5°

  • h = −11 → 11

  • k = −18 → 18

  • l = −20 → 20

Refinement
  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.048

  • wR(F2) = 0.142

  • S = 1.05

  • 4383 reflections

  • 255 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • w = 1/[σ2(Fo2) + (0.0817P)2 + 0.4133P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max = 0.014

  • Δρmax = 0.65 e Å−3

  • Δρmin = −0.24 e Å−3

Table 1
Selected geometric parameters (Å, °) for (I)[link]

O1—C11 1.377 (2) 
O2—C21 1.374 (2)
N1—C2 1.338 (2)
N1—C6 1.340 (3)
C4—C7 1.514 (2)
C7—C24 1.529 (2)
C7—C14 1.533 (2)
C2—N1—C6 122.11 (17)
C4—C7—C24 112.16 (14)
C4—C7—C14 109.72 (14)
C24—C7—C14 115.71 (14)

Table 2
Hydrogen-bond geometry (Å, °) for (I)[link]

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯Cl 0.94 (3) 2.19 (3) 3.0371 (17) 150 (2)
O1—HO1⋯Cli 0.81 (2) 2.36 (3) 3.0732 (15) 147 (2)
O2—HO2⋯Clii 0.84 (3) 2.45 (3) 3.1990 (15) 148 (2)
C7—H7⋯Cliv 1.00 2.99 3.9568 (19) 162
C17—H171⋯Clv 0.98 3.02 3.956 (2) 160
C18—H181⋯Clvi 0.98 3.11 3.802 (2) 129
Symmetry codes: (i) [-x+{\script{5\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) x, y-1, z; (iii) -x+1, -y+2, -z; (iv) [-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (v) [x+{\script{1\over 2}}, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]; (vi) -x+2, -y+2, -z.

Compound (II)[link]

Crystal data
  • C22H24NO2+·Br

  • Mr = 414.33

  • Monoclinic, P 21 /n

  • a = 8.7217 (4) Å

  • b = 14.7461 (6) Å

  • c = 15.4836 (6) Å

  • β = 101.59 (1)°

  • V = 1950.73 (14) Å3

  • Z = 4

  • Dx = 1.411 Mg m−3

  • Mo Kα radiation

  • Cell parameters from 5710 reflections

  • θ = 2.8–30.5°

  • μ = 2.12 mm−1

  • T = 120 (2) K

  • Tetragonal prism, pale orange

  • 0.32 × 0.22 × 0.12 mm

Data collection
  • Bruker APEX CCD area-detector diffractometer

  • ω scans

  • Absorption correction: multi-scan(SADABS; Bruker, 2003[Bruker (2003). SAINT (Version 6.45a) and SADABS (Version 2.10). Bruker AXS Inc., Madison, Wisconsin, USA.])Tmin = 0.803, Tmax = 1.000

  • 21 226 measured reflections

  • 5943 independent reflections

  • 5263 reflections with I > 2σ(I)

  • Rint = 0.017

  • θmax = 30.5°

  • h = −12 → 12

  • k = −20 → 21

  • l = −21 → 22

Refinement
  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.027

  • wR(F2) = 0.070

  • S = 1.05

  • 5942 reflections

  • 256 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • w = 1/[σ2(Fo2) + (0.0502P)2 + 0.4161P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max = 0.002

  • Δρmax = 0.90 e Å−3

  • Δρmin = −0.23 e Å−3

Table 3
Selected geometric parameters (Å, °) for (II)[link]

O1—C11 1.3718 (14)
O2—C21 1.3746 (15)
N1—C2 1.3377 (18)
N1—C6 1.340 (2)
C4—C7 1.5139 (17)
C7—C24 1.5270 (17)
C7—C14 1.5293 (16)
C2—N1—C6 122.65 (12)
C4—C7—C24 111.83 (10)
C4—C7—C14 109.97 (10)
C24—C7—C14 116.38 (10)

Table 4
Hydrogen-bond geometry (Å, °) for (II)[link]

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯Br 0.84 (3) 2.46 (3) 3.2090 (11) 150 (2)
O1—HO1⋯Bri 0.83 (2) 2.47 (2) 3.1984 (10) 148 (2)
O2—HO2⋯Brii 0.80 (2) 2.70 (2) 3.3745 (10) 143 (2)
C7—H7⋯Briv 1.00 2.92 3.8791 (12) 161
C17—H171⋯Brv 0.98 3.05 3.9690 (15) 157
C18—H181⋯Brvi 0.98 3.13 3.8243 (15) 129
Symmetry codes: (i) [-x+{\script{5\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) x, y-1, z; (iii) -x+1, -y+2, -z; (iv) [-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (v) [x+{\script{1\over 2}}, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]; (vi) -x+2, -y+2, -z.

Table 5
Corrected hydrogen-bond distances (Å) and angles (°) in (I)[link] and (II)[link]

Calculated for idealized bond lengths N—H = 1.01 Å, O—H = 0.97 Å and C—H = 1.08 Å, as determined by neutron diffraction (Allen et al., 1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]). X = Cl in (I)[link] and Br in (II)[link].

D—H⋯X D⋯Cl H⋯Cl D—H⋯Cl D⋯Br H⋯Br D—H⋯Br
N1—H1⋯X 3.037 (2) 2.13 (3) 149 (2) 3.209 (1) 2.33 (3) 145 (2)
O1—HO1⋯Xi 3.073 (2) 2.23 (3) 145 (2) 3.198 (1) 2.35 (2) 146 (2)
O2—HO2⋯Xii 3.199 (2) 2.35 (3) 147 (2) 3.375 (1) 2.61 (2) 136 (2)
C7—H7⋯Xiv 3.957 (2) 2.92 162 3.879 (1) 2.84 161 (2)
C17—H171⋯Xv 3.956 (2) 2.93 159 3.969 (1) 2.97 155 (2)
C18—H181⋯Xvi 3.802 (2) 3.05 127 3.824 (1) 3.05 130 (2)
Symmetry codes: (i) [-x+{\script{5\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) x, y-1, z; (iv) [-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (v) [x+{\script{1\over 2}}, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]; (vi) -x+2, -y+2, -z.

All H atoms were located in a difference Fourier synthesis. Methyl groups were treated as rigid bodies rotating around the C—C bonds, with fixed C—H distances of 0.98 Å and a common (refined) Uiso(H) value for each group. H atoms bonded to O and N atoms were refined in the isotropic approximation. The remaining H atoms were treated as riding on their parent C atoms, with Csp2—H = 0.95 Å and C7—H = 1.00 Å, and Uiso(H) = 1.2Ueq(C).

For both compounds, data collection: SMART (Bruker, 2001[Bruker (2001). SMART (Version 5.625), SAINT (Version 6.02a) and SHELXTL (Version 6.12). Bruker AXS Inc., Madison, Wisconsin, USA.]). Cell refinement: SMART for (I)[link]; SAINT (Bruker, 2003[Bruker (2003). SAINT (Version 6.45a) and SADABS (Version 2.10). Bruker AXS Inc., Madison, Wisconsin, USA.]) for (II)[link]. Data reduction: SAINT (Bruker, 2001[Bruker (2001). SMART (Version 5.625), SAINT (Version 6.02a) and SHELXTL (Version 6.12). Bruker AXS Inc., Madison, Wisconsin, USA.]) for (I)[link]; SAINT (Bruker, 2003[Bruker (2003). SAINT (Version 6.45a) and SADABS (Version 2.10). Bruker AXS Inc., Madison, Wisconsin, USA.]) for (II)[link]. For both compounds, program(s) used to solve structure: SHELXTL (Bruker, 2001[Bruker (2001). SMART (Version 5.625), SAINT (Version 6.02a) and SHELXTL (Version 6.12). Bruker AXS Inc., Madison, Wisconsin, USA.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

The coordination chemistry of anions is a fast-growing area of supramolecular chemistry (see, for example, Bianchi et al., 1997; Schmidtchen & Berger, 1997), both on account of the importance of anion binding, recognition and transport in many biochemical processes (Lehn, 1995; Beer, 1996; Pajewski et al., 2004, and references therein) and because anions can be used to direct the self-assembly of organic (and organometallic) molecules in desired ways (Gale, 2000, 2001; Sessler et al., 2003). Thus, the Cl anion has been successfully used to assemble double-helical motifs of various molecules containing aromatic groups, with π-stacking within the helices (Hasenknopf et al., 1996, 1997). Indeed, halide anions can be particularly useful for such applications because of the high flexibility of their coordination (Ilioudis et al., 2004). In the present work, we have investigated the effects of Cl and Br ions on the assembly of 4-[bis(3,5-dimethyl-4-hydroxyphenyl)methyl]pyridine, L, a molecule with a relatively rigid tripodal framework. To our knowledge, neither this molecule nor any other with two p-phenol and one pyridyl groups linked through a single C atom has been structurally characterized to date. Meanwhile, related compounds ArCH(C6H4OH-p)2 (e.g. with Ar = C6H4Br-p) have been used as ligands to obtain topologically chiral [2]catenane complexes of gold(I), whereby the unsymmetrical `hinge group' ArCH plays a crucial role in imposing chirality (McArdle et al., 2002).

Originally, we intended to prepare a copper(II) complex of L to serve as a building block for a supermolecule. However, crystallization from an aqueous solution containing equivalent quantities of HCl, L and CuCl2·2H2O unexpectedly yielded LH+Cl, (I). This compound and its analogue LH+Br, (II), were also formed from an acidic solution of L and HCl (or HBr) in the presence of catalytic quantities of CuCl2·2H2O, but in the complete absence of the latter we could not obtain any crystals of the salts.

The crystals of (I) and (II) are isomorphous. The asymmetric unit comprises one halide anion and one LH+ cation (with N1 protonated), which adopts practically the same propeller-like conformation; the pyridine ring and benzene rings A and B Please define (Fig. 1) are inclined to the C4/C14/C24 plane in the same sense, by 53.9 (1), 42.6 (1) and 41.5 (1)°, respectively, in (I) and by 55.0 (1), 39.7 (1) and 41.4 (1)°, respectively, in (II).

The asymmetric unit contains three H atoms (two hydroxyl and one pyridinium) capable of forming strong hydrogen bonds, and three potential acceptors, viz. two O atoms and the halide anion. In fact, only the anion acts as the acceptor of all three such bonds (Table 5), probably because competitiveness of the O atoms as acceptors is severely diminished by the masking effect of the adjacent methyl groups. The anion and the three bonded H atoms are coplanar to within 0.1 Å. The configuration can be described as T-shaped rather than trigonal (Fig. 2), which is relatively rare but not unknown (Ilioudis et al., 2000). Indeed, halide anions are known to behave as `spherical' acceptors without any clearly favoured coordination geometry, although some preference towards quasi-tetrahedral and trigonal configurations can be discerned (Ilioudis et al., 2000).

These three strong hydrogen bonds link the cations into ribbons running parallel to the crystallographic b axis (Fig. 2). Besides these, the anion participates in three weak interactions (Table 5) with aromatic and methyl H atoms, with each of the six contacts involving a different cation. It is noteworthy that strong bonds in (II) are longer than those in (I), roughly in line with the increase of the ionic radius of Br (1.96 Å; Shannon & Prewitt, 1969) compared with Cl (1.81 Å), but the weak bonds lengthen much less or even contract on going from (I) to (II). The difference can be explained by the higher polarizability of the Br anion and hence higher (C)H···X dispersion interactions in (II), while this difference is less relevant for the strong hydrogen bonds, which have larger contributions of (time-independent) ion–dipole interactions. The weak hydrogen bonds are roughly normal to the T-plane of the strong ones, while the wide angle ϕ1 is occupied by the pyridine ring atom C2 of another cation, generated by inversion (1 − x, 2 − y, −z). The corresponding distances, Cl···C2 3.382 (2) and Br···C2 3.458 (1) Å, are both shorter than the sums of the van der Waals radii (3.53 and 3.65 Å, respectively; Rowland & Taylor, 1996).

Thus, through this system of hydrogen bonds, the halide anions are decisive in directing the packing of the LH+ cations. However, the resulting structure is ribbon-like rather than helical. Substitution of a Br anion for Cl affects different types of hydrogen bonds selectively. Also noteworthy is the ability of copper(II) chloride to facilitate the crystallization of (I) and (II) without itself being incorporated into the structure. This effect may be useful as a method for controlling molecular self-assembly. Therefore, we intend a further study of its mechanism and possible applications.

Experimental top

Compound L was synthesized by condensation of 2,6-dimethyl-phenol with pyridine-4-carboxaldehyde. Pyridine-4-carboxaldehyde (0.534 g, 5.0 mmol) and 2,6-dimethylphenol (1.221 g, 10 mmol) were dissolved in 1 M sulfuric acid (1.4 ml) mixed with methanol (10 ml). Trifloroacetic acid (1 ml) was then added. The mixture was heated at 353 K for 8 h, after which the solvents were removed under vacuum. The residue was dissolved in water (15 ml), extracted with ethyl acetate (15 ml) and dried over anhydrous Na2SO4. Removal of the solvents and subsequent column chromatography (silica gel 60–120 mesh; hexanes/ethyl acetate, 4:1) gave L as a white solid (yield: 1.43 g, 86%; m.p. 478 K). Spectroscopic analysis: IR (KBr, ν, cm−1): 3385 (s), 3083 (s), 2914 (w), 2079 (w), 1634 (s), 1485 (s), 1147 (s), 1004 (s); 1H NMR (400 MHz, DMSO-d6, δ, p.p.m.): 2.18 (s, 12H), 3.70 (s, 2H), 5.43 (s, 1H), 6.60 (s, 4H), 7.6 (d, 2H, J = 6.4 Hz), 6.7 (d, 2H, J = 6.4 Hz); 13C NMR (100 MHz, DMSO-d6, δ, p.p.m.): 17.4, 55.68, 125.18, 127.78, 129.25, 131.46, 141.63, 152.81, 166.53. Slow evaporation of a solution of L (0.332 g, 1 mmol) and HCl (0.3 ml, 11.5 M) in methanol in the presence of CuCl2·2H2O (0.085 g, 5 mol%) gave (I) as a pale-yellow precipitate, which was recrystallized from methanol (m.p. 487 K). IR (KBr, ν, cm−1): 3375 (s), 2786 (s), 2034 (s), 1629 (s), 1481 (s), 1317 (s), 1194 (s), 1024 (w). Slow evaporation of a solution of L (0.333 g, 1 mmol) in methanol containing HBr (0.5 ml, 60%) and cupric bromide (0.012 g, 5mol%) gave (II) as pale-orange crystals (m.p. 492 K). IR (KBr, ν, cm−1): 3334 (s), 3228 (w), 2930 (s), 2022 (s), 1775 (s), 1629 (s), 1492 (s), 1190 (s), 1134 (w).

Refinement top

All H atoms were located in a difference Fourier synthesis. Methyl groups were treated as rigid bodies rotating around the C—C bonds, with fixed C—H distances of 0.98 Å and a common (refined) Uiso(H) for each group. The H atoms bonded to O and N were refined in the isotropic approximation. The remaining H atoms were treated as riding on their parent C atoms, with Csp2—H = 0.95 Å and C7—H = 1.00 Å, and with Uiso(H) = 1.2Ueq(C).

Computing details top

For both compounds, data collection: SMART (Bruker, 2001). Cell refinement: SMART for (I); SAINT (Bruker, 2003) for (II). Data reduction: SAINT (Bruker, 2001) for (I); SAINT for (II). For both compounds, program(s) used to solve structure: SHELXTL (Bruker, 2001); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Figures top
[Figure 1] Fig. 1. The cations and anions in the structures of (a) (I) and (b) (II), showing the atomic numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. The system of strong hydrogen bonds in structures (I) (X = Cl) and (II) (X = Br). The H···X···H angles are ϕ1 170, ϕ2 84 and ϕ3 104° in (I), and ϕ1 173, ϕ2 82 and ϕ3 105° in (II); s.u.s are ~1°. From the Coeditor: Please consider defining the shading used to identify the atom types.
(I) 4-[bis(4-hydroxy-3,5-dimethylphenyl)methyl]pyridinium chloride top
Crystal data top
C22H24NO2+·ClF(000) = 784
Mr = 369.87Dx = 1.286 Mg m3
Monoclinic, P21/nMelting point: 487 K
Hall symbol: -P 2ynMo Kα radiation, λ = 0.71073 Å
a = 8.6590 (2) ÅCell parameters from 4680 reflections
b = 14.3920 (17) Åθ = 2.4–29.7°
c = 15.7057 (12) ŵ = 0.22 mm1
β = 102.519 (14)°T = 120 K
V = 1910.7 (3) Å3Tetragonal prism, yellow
Z = 40.26 × 0.15 × 0.09 mm
Data collection top
Bruker SMART 6000 CCD area-detector
diffractometer
4383 independent reflections
Radiation source: fine-focus sealed tube3330 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.058
Detector resolution: 5.6 pixels mm-1θmax = 27.5°, θmin = 1.9°
ω scansh = 1111
Absorption correction: integration
(XPREP in SHELXTL; Bruker, 2001)
k = 1818
Tmin = 0.953, Tmax = 0.984l = 2020
21158 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.048Hydrogen site location: difference Fourier map
wR(F2) = 0.142H atoms treated by a mixture of independent and constrained refinement
S = 1.05 w = 1/[σ2(Fo2) + (0.0817P)2 + 0.4133P]
where P = (Fo2 + 2Fc2)/3
4383 reflections(Δ/σ)max = 0.014
255 parametersΔρmax = 0.65 e Å3
0 restraintsΔρmin = 0.24 e Å3
Crystal data top
C22H24NO2+·ClV = 1910.7 (3) Å3
Mr = 369.87Z = 4
Monoclinic, P21/nMo Kα radiation
a = 8.6590 (2) ŵ = 0.22 mm1
b = 14.3920 (17) ÅT = 120 K
c = 15.7057 (12) Å0.26 × 0.15 × 0.09 mm
β = 102.519 (14)°
Data collection top
Bruker SMART 6000 CCD area-detector
diffractometer
4383 independent reflections
Absorption correction: integration
(XPREP in SHELXTL; Bruker, 2001)
3330 reflections with I > 2σ(I)
Tmin = 0.953, Tmax = 0.984Rint = 0.058
21158 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0480 restraints
wR(F2) = 0.142H atoms treated by a mixture of independent and constrained refinement
S = 1.05Δρmax = 0.65 e Å3
4383 reflectionsΔρmin = 0.24 e Å3
255 parameters
Special details top

Experimental. The data collection nominally covered full sphere of reciprocal space, by a combination of 3 sets of ω scans; each set at different ϕ angles and each scan (5 sec exposure) covering 0.3° in ω. Crystal to detector distance 4.86 cm.

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. Methyl groups were refined as rigid rotating bodies with a common refined U for three H atoms, H atoms bound to O or N - All H-atom parameters refined, other H atoms - riding (H-atom parameters constrained).

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cl0.67927 (5)1.10752 (3)0.04967 (3)0.02800 (15)
O11.54504 (15)0.67658 (10)0.30663 (9)0.0266 (3)
H011.587 (3)0.6452 (16)0.3478 (16)0.034 (6)*
O20.58085 (17)0.32211 (10)0.04137 (9)0.0304 (3)
H020.641 (3)0.276 (2)0.0410 (18)0.056 (8)*
N10.70051 (18)0.89947 (11)0.08251 (12)0.0267 (4)
H10.667 (3)0.9558 (18)0.0540 (16)0.041 (7)*
C20.6963 (2)0.82318 (13)0.03341 (13)0.0264 (4)
H20.65680.82640.02790.032*
C30.7495 (2)0.73993 (12)0.07229 (12)0.0236 (4)
H30.74690.68560.03770.028*
C40.80714 (19)0.73532 (12)0.16210 (12)0.0206 (4)
C50.8070 (2)0.81678 (13)0.21036 (13)0.0257 (4)
H50.84350.81570.27190.031*
C60.7545 (2)0.89790 (13)0.16917 (13)0.0277 (4)
H60.75610.95350.20200.033*
C70.8733 (2)0.64730 (12)0.20894 (11)0.0215 (4)
H70.83800.64700.26550.026*
C111.38339 (19)0.66520 (13)0.28506 (11)0.0221 (4)
C121.3035 (2)0.59837 (12)0.32347 (12)0.0237 (4)
C131.1390 (2)0.59376 (12)0.29654 (12)0.0235 (4)
H131.08300.54920.32270.028*
C141.0544 (2)0.65237 (12)0.23259 (11)0.0215 (4)
C151.1390 (2)0.71711 (13)0.19534 (12)0.0221 (4)
H151.08330.75710.15100.027*
C161.3033 (2)0.72516 (13)0.22110 (12)0.0240 (4)
C171.3927 (2)0.53286 (15)0.39161 (14)0.0350 (5)
H1711.31740.49700.41690.046 (4)*
H1721.46220.56860.43760.046 (4)*
H1731.45640.49030.36460.046 (4)*
C181.3910 (2)0.79781 (15)0.18157 (15)0.0343 (5)
H1811.31520.83600.14080.055 (4)*
H1821.46350.76750.15030.055 (4)*
H1831.45140.83730.22790.055 (4)*
C210.6598 (2)0.39988 (12)0.07845 (12)0.0228 (4)
C220.8205 (2)0.41535 (12)0.08192 (12)0.0228 (4)
C230.8903 (2)0.49566 (12)0.12383 (11)0.0222 (4)
H230.99990.50650.12760.027*
C240.8034 (2)0.55992 (12)0.16001 (11)0.0210 (4)
C250.6415 (2)0.54374 (12)0.15194 (11)0.0221 (4)
H250.58010.58870.17410.026*
C260.5681 (2)0.46459 (12)0.11279 (12)0.0224 (4)
C270.9156 (2)0.34865 (14)0.04012 (14)0.0312 (4)
H2710.91730.28760.06800.071 (5)*
H2721.02410.37190.04740.071 (5)*
H2730.86750.34300.02220.071 (5)*
C280.3949 (2)0.44674 (14)0.10888 (13)0.0280 (4)
H2810.35390.49410.14300.038 (4)*
H2820.38200.38510.13300.038 (4)*
H2830.33620.44940.04810.038 (4)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl0.0247 (2)0.0210 (2)0.0341 (3)0.00200 (16)0.00290 (19)0.00081 (17)
O10.0167 (6)0.0340 (8)0.0270 (7)0.0015 (5)0.0004 (5)0.0030 (6)
O20.0286 (7)0.0195 (7)0.0394 (8)0.0014 (6)0.0010 (6)0.0047 (6)
N10.0199 (7)0.0197 (8)0.0385 (9)0.0008 (6)0.0015 (7)0.0012 (7)
C20.0221 (9)0.0249 (9)0.0296 (10)0.0015 (7)0.0003 (7)0.0008 (7)
C30.0213 (9)0.0219 (9)0.0268 (9)0.0015 (7)0.0035 (7)0.0042 (7)
C40.0135 (7)0.0229 (9)0.0254 (9)0.0022 (6)0.0041 (6)0.0019 (7)
C50.0227 (9)0.0271 (10)0.0266 (9)0.0016 (7)0.0039 (7)0.0055 (7)
C60.0226 (9)0.0231 (9)0.0365 (11)0.0010 (7)0.0047 (8)0.0085 (8)
C70.0183 (8)0.0245 (9)0.0207 (8)0.0011 (7)0.0021 (7)0.0017 (7)
C110.0164 (8)0.0273 (9)0.0219 (9)0.0002 (7)0.0021 (7)0.0036 (7)
C120.0228 (9)0.0258 (9)0.0210 (9)0.0007 (7)0.0017 (7)0.0002 (7)
C130.0209 (8)0.0236 (9)0.0249 (9)0.0026 (7)0.0027 (7)0.0007 (7)
C140.0195 (8)0.0227 (9)0.0210 (9)0.0004 (7)0.0014 (7)0.0028 (7)
C150.0200 (8)0.0240 (9)0.0215 (8)0.0019 (7)0.0026 (7)0.0016 (7)
C160.0205 (8)0.0270 (9)0.0244 (9)0.0007 (7)0.0049 (7)0.0003 (7)
C170.0254 (10)0.0381 (12)0.0390 (12)0.0003 (8)0.0015 (8)0.0140 (9)
C180.0228 (9)0.0394 (12)0.0412 (12)0.0007 (8)0.0079 (8)0.0130 (9)
C210.0270 (9)0.0176 (8)0.0209 (9)0.0020 (7)0.0008 (7)0.0016 (7)
C220.0253 (9)0.0218 (9)0.0213 (9)0.0025 (7)0.0049 (7)0.0031 (7)
C230.0196 (8)0.0230 (9)0.0231 (9)0.0001 (7)0.0031 (7)0.0022 (7)
C240.0209 (8)0.0210 (9)0.0198 (8)0.0005 (7)0.0014 (7)0.0033 (7)
C250.0220 (9)0.0212 (9)0.0221 (9)0.0019 (7)0.0027 (7)0.0002 (7)
C260.0206 (8)0.0222 (9)0.0224 (9)0.0004 (7)0.0004 (7)0.0043 (7)
C270.0329 (10)0.0259 (10)0.0358 (11)0.0023 (8)0.0095 (9)0.0041 (8)
C280.0221 (9)0.0275 (10)0.0326 (10)0.0039 (7)0.0021 (8)0.0013 (8)
Geometric parameters (Å, º) top
O1—C111.377 (2)C15—C161.397 (2)
O1—H010.81 (2)C15—H150.9500
O2—C211.374 (2)C16—C181.503 (3)
O2—H020.84 (3)C17—H1710.9800
N1—C21.338 (2)C17—H1720.9800
N1—C61.340 (3)C17—H1730.9800
N1—H10.94 (3)C18—H1810.9800
C2—C31.378 (3)C18—H1820.9800
C2—H20.9500C18—H1830.9800
C3—C41.392 (3)C21—C221.398 (3)
C3—H30.9500C21—C261.405 (3)
C4—C51.396 (2)C22—C231.401 (2)
C4—C71.514 (2)C22—C271.505 (3)
C5—C61.364 (3)C23—C241.389 (2)
C5—H50.9500C23—H230.9500
C6—H60.9500C24—C251.399 (2)
C7—C241.529 (2)C25—C261.382 (2)
C7—C141.533 (2)C25—H250.9500
C7—H71.0000C26—C281.510 (2)
C11—C161.390 (3)C27—H2710.9800
C11—C121.396 (3)C27—H2720.9800
C12—C131.397 (2)C27—H2730.9800
C12—C171.507 (3)C28—H2810.9800
C13—C141.392 (2)C28—H2820.9800
C13—H130.9500C28—H2830.9800
C14—C151.390 (2)
C11—O1—H01112.5 (17)C15—C16—C18120.79 (16)
C21—O2—H02112.7 (19)C12—C17—H171109.5
C2—N1—C6122.11 (17)C12—C17—H172109.5
C2—N1—H1117.7 (15)H171—C17—H172109.5
C6—N1—H1120.1 (15)C12—C17—H173109.5
N1—C2—C3119.58 (18)H171—C17—H173109.5
N1—C2—H2120.2H172—C17—H173109.5
C3—C2—H2120.2C16—C18—H181109.5
C2—C3—C4120.16 (17)C16—C18—H182109.5
C2—C3—H3119.9H181—C18—H182109.5
C4—C3—H3119.9C16—C18—H183109.5
C3—C4—C5117.89 (17)H181—C18—H183109.5
C3—C4—C7123.17 (16)H182—C18—H183109.5
C5—C4—C7118.92 (16)O2—C21—C22123.08 (17)
C6—C5—C4120.04 (18)O2—C21—C26115.59 (16)
C6—C5—H5120.0C22—C21—C26121.33 (16)
C4—C5—H5120.0C21—C22—C23118.31 (16)
N1—C6—C5120.21 (17)C21—C22—C27121.03 (16)
N1—C6—H6119.9C23—C22—C27120.65 (16)
C5—C6—H6119.9C24—C23—C22121.62 (16)
C4—C7—C24112.16 (14)C24—C23—H23119.2
C4—C7—C14109.72 (14)C22—C23—H23119.2
C24—C7—C14115.71 (14)C23—C24—C25118.24 (16)
C4—C7—H7106.2C23—C24—C7124.22 (15)
C24—C7—H7106.2C25—C24—C7117.53 (15)
C14—C7—H7106.2C26—C25—C24122.19 (17)
O1—C11—C16115.17 (16)C26—C25—H25118.9
O1—C11—C12123.25 (16)C24—C25—H25118.9
C16—C11—C12121.57 (16)C25—C26—C21118.23 (16)
C13—C12—C11118.05 (16)C25—C26—C28121.04 (16)
C13—C12—C17121.14 (17)C21—C26—C28120.72 (16)
C11—C12—C17120.81 (16)C22—C27—H271109.5
C14—C13—C12122.14 (17)C22—C27—H272109.5
C14—C13—H13118.9H271—C27—H272109.5
C12—C13—H13118.9C22—C27—H273109.5
C15—C14—C13117.87 (16)H271—C27—H273109.5
C15—C14—C7122.30 (15)H272—C27—H273109.5
C13—C14—C7119.75 (16)C26—C28—H281109.5
C14—C15—C16122.00 (16)C26—C28—H282109.5
C14—C15—H15119.0H281—C28—H282109.5
C16—C15—H15119.0C26—C28—H283109.5
C11—C16—C15118.36 (16)H281—C28—H283109.5
C11—C16—C18120.84 (16)H282—C28—H283109.5
C5—C4—C7—C1474.99 (19)C4—C7—C24—C2565.1 (2)
C4—C7—C14—C1515.3 (2)C13—C14—C7—C2470.4 (2)
C3—C4—C7—C2426.7 (2)C14—C7—C24—C2311.6 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···Cl0.94 (3)2.19 (3)3.0371 (17)150 (2)
O1—H01···Cli0.81 (2)2.36 (3)3.0732 (15)147 (2)
O2—H02···Clii0.84 (3)2.45 (3)3.1990 (15)148 (2)
C2—H2···Cliii0.953.013.3813 (19)105
C7—H7···Cliv1.002.993.9568 (19)162
C17—H171···Clv0.983.023.956 (2)160
C18—H181···Clvi0.983.113.802 (2)129
Symmetry codes: (i) x+5/2, y1/2, z+1/2; (ii) x, y1, z; (iii) x+1, y+2, z; (iv) x+3/2, y1/2, z+1/2; (v) x+1/2, y+3/2, z+1/2; (vi) x+2, y+2, z.
(II) 4-[bis(4-hydroxy-3,5-dimethylphenyl)methyl]pyridinium bromide top
Crystal data top
C22H24NO2+·BrF(000) = 856
Mr = 414.33Dx = 1.411 Mg m3
Monoclinic, P21/nMelting point: 492 K
Hall symbol: -P 2ynMo Kα radiation, λ = 0.71073 Å
a = 8.7217 (4) ÅCell parameters from 5710 reflections
b = 14.7461 (6) Åθ = 2.8–30.5°
c = 15.4836 (6) ŵ = 2.12 mm1
β = 101.59 (1)°T = 120 K
V = 1950.73 (14) Å3Tetragonal prism, pale orange
Z = 40.32 × 0.22 × 0.12 mm
Data collection top
Bruker APEX CCD area-detector
diffractometer
5943 independent reflections
Radiation source: 60W microfocus Bede Microsource with glass polycapillary optics5263 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.017
Detector resolution: 8 pixels mm-1θmax = 30.5°, θmin = 1.9°
ω scansh = 1212
Absorption correction: multi-scan
(SADABS; Bruker, 2003)
k = 2021
Tmin = 0.803, Tmax = 1.000l = 2122
21226 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.027Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.070H atoms treated by a mixture of independent and constrained refinement
S = 1.05 w = 1/[σ2(Fo2) + (0.0502P)2 + 0.4161P]
where P = (Fo2 + 2Fc2)/3
5942 reflections(Δ/σ)max = 0.002
256 parametersΔρmax = 0.90 e Å3
0 restraintsΔρmin = 0.23 e Å3
Crystal data top
C22H24NO2+·BrV = 1950.73 (14) Å3
Mr = 414.33Z = 4
Monoclinic, P21/nMo Kα radiation
a = 8.7217 (4) ŵ = 2.12 mm1
b = 14.7461 (6) ÅT = 120 K
c = 15.4836 (6) Å0.32 × 0.22 × 0.12 mm
β = 101.59 (1)°
Data collection top
Bruker APEX CCD area-detector
diffractometer
5943 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2003)
5263 reflections with I > 2σ(I)
Tmin = 0.803, Tmax = 1.000Rint = 0.017
21226 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0270 restraints
wR(F2) = 0.070H atoms treated by a mixture of independent and constrained refinement
S = 1.05Δρmax = 0.90 e Å3
5942 reflectionsΔρmin = 0.23 e Å3
256 parameters
Special details top

Experimental. The data collection nominally covered full sphere of reciprocal space, by a combination of 3 sets of ω scans; each set at different ϕ angles and each scan covering 0.3° in ω.

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. Methyl groups were refined as rigid rotating bodies with a common refined U for three H atoms, H atoms bound to O or N - All H-atom parameters refined, other H atoms - riding (H-atom parameters constrained).

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Br0.676256 (14)1.104801 (8)0.049778 (8)0.01935 (5)
O11.53558 (11)0.67884 (7)0.30619 (6)0.02138 (18)
H011.580 (2)0.6448 (14)0.3461 (13)0.031 (5)*
O20.58366 (13)0.32722 (7)0.04327 (7)0.0261 (2)
H020.644 (3)0.2868 (17)0.0411 (14)0.043 (6)*
N10.69909 (14)0.88983 (8)0.08199 (9)0.0229 (2)
H10.666 (2)0.9386 (18)0.0574 (14)0.041 (6)*
C20.69750 (15)0.81554 (9)0.03223 (9)0.0222 (2)
H20.66020.81860.02970.027*
C30.75057 (15)0.73441 (8)0.07182 (8)0.0190 (2)
H30.74970.68130.03700.026 (4)*
C40.80539 (13)0.73026 (8)0.16255 (8)0.0159 (2)
C50.80231 (15)0.80967 (9)0.21150 (9)0.0208 (2)
H50.83710.80870.27370.025*
C60.74897 (16)0.88898 (9)0.16968 (10)0.0231 (3)
H60.74740.94310.20280.028*
C70.87305 (13)0.64491 (8)0.20970 (8)0.0156 (2)
H70.83820.64470.26740.019*
C111.37668 (14)0.66615 (8)0.28433 (8)0.0167 (2)
C121.29883 (15)0.59747 (8)0.32041 (8)0.0184 (2)
C131.13635 (15)0.59164 (8)0.29451 (8)0.0186 (2)
H131.08190.54620.31980.022*
C141.05168 (14)0.65102 (8)0.23220 (8)0.0161 (2)
C151.13420 (14)0.71704 (9)0.19643 (8)0.0187 (2)
H151.07850.75710.15310.022*
C161.29571 (14)0.72639 (9)0.22197 (8)0.0191 (2)
C171.38861 (17)0.53198 (11)0.38671 (11)0.0302 (3)
H1711.31490.49320.40990.048 (4)*
H1721.45290.56590.43520.048 (4)*
H1731.45630.49420.35810.048 (4)*
C181.38276 (16)0.79933 (11)0.18407 (11)0.0309 (3)
H1811.30840.83620.14260.049 (4)*
H1821.45840.77150.15310.049 (4)*
H1831.43830.83790.23180.049 (4)*
C210.66121 (16)0.40333 (8)0.08027 (9)0.0183 (2)
C220.82030 (15)0.41792 (9)0.08246 (8)0.0189 (2)
C230.89009 (14)0.49652 (8)0.12421 (8)0.0178 (2)
H230.99850.50680.12720.021*
C240.80389 (14)0.55947 (8)0.16128 (8)0.0164 (2)
C250.64388 (14)0.54369 (8)0.15516 (8)0.0176 (2)
H250.58340.58730.17870.021*
C260.57090 (14)0.46625 (8)0.11571 (8)0.0180 (2)
C270.91482 (18)0.35192 (10)0.04044 (10)0.0270 (3)
H2710.91650.29290.06970.052 (4)*
H2721.02210.37460.04650.052 (4)*
H2730.86740.34530.02220.052 (4)*
C280.39958 (16)0.44905 (10)0.11277 (10)0.0244 (3)
H2810.35830.49600.14660.042 (3)*
H2820.38660.38940.13830.042 (3)*
H2830.34250.45050.05140.042 (3)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br0.01843 (7)0.01508 (7)0.02192 (7)0.00139 (4)0.00220 (5)0.00117 (4)
O10.0133 (4)0.0265 (5)0.0230 (4)0.0004 (3)0.0006 (3)0.0047 (4)
O20.0260 (5)0.0150 (4)0.0343 (5)0.0018 (4)0.0008 (4)0.0052 (4)
N10.0177 (5)0.0153 (5)0.0335 (6)0.0017 (4)0.0002 (4)0.0020 (4)
C20.0202 (6)0.0201 (6)0.0243 (6)0.0005 (5)0.0004 (5)0.0017 (5)
C30.0192 (5)0.0162 (5)0.0201 (5)0.0009 (4)0.0007 (4)0.0022 (4)
C40.0124 (5)0.0152 (5)0.0194 (5)0.0001 (4)0.0014 (4)0.0021 (4)
C50.0193 (5)0.0198 (6)0.0224 (6)0.0004 (4)0.0017 (4)0.0066 (5)
C60.0191 (6)0.0173 (6)0.0322 (7)0.0003 (4)0.0034 (5)0.0076 (5)
C70.0144 (5)0.0158 (5)0.0161 (5)0.0005 (4)0.0019 (4)0.0007 (4)
C110.0139 (5)0.0195 (5)0.0162 (5)0.0006 (4)0.0019 (4)0.0009 (4)
C120.0168 (5)0.0189 (5)0.0181 (5)0.0011 (4)0.0001 (4)0.0020 (4)
C130.0178 (5)0.0176 (5)0.0194 (5)0.0013 (4)0.0013 (4)0.0021 (4)
C140.0142 (5)0.0174 (5)0.0157 (5)0.0009 (4)0.0005 (4)0.0015 (4)
C150.0163 (5)0.0207 (6)0.0183 (5)0.0020 (4)0.0016 (4)0.0037 (4)
C160.0167 (5)0.0212 (6)0.0196 (5)0.0004 (4)0.0043 (4)0.0041 (4)
C170.0209 (6)0.0313 (7)0.0359 (7)0.0012 (5)0.0002 (6)0.0162 (6)
C180.0187 (6)0.0355 (8)0.0382 (8)0.0009 (5)0.0047 (6)0.0184 (6)
C210.0224 (6)0.0131 (5)0.0175 (5)0.0018 (4)0.0006 (4)0.0014 (4)
C220.0219 (6)0.0162 (5)0.0184 (5)0.0026 (4)0.0034 (4)0.0012 (4)
C230.0171 (5)0.0175 (5)0.0184 (5)0.0006 (4)0.0029 (4)0.0018 (4)
C240.0173 (5)0.0143 (5)0.0166 (5)0.0000 (4)0.0009 (4)0.0012 (4)
C250.0169 (5)0.0164 (5)0.0187 (5)0.0008 (4)0.0014 (4)0.0000 (4)
C260.0177 (5)0.0170 (5)0.0178 (5)0.0007 (4)0.0000 (4)0.0024 (4)
C270.0301 (7)0.0212 (6)0.0314 (7)0.0037 (5)0.0099 (6)0.0048 (5)
C280.0182 (6)0.0236 (6)0.0304 (7)0.0036 (5)0.0024 (5)0.0011 (5)
Geometric parameters (Å, º) top
O1—C111.3718 (14)C15—C161.3914 (17)
O1—H010.83 (2)C15—H150.9500
O2—C211.3746 (15)C16—C181.5022 (18)
O2—H020.80 (2)C17—H1710.9800
N1—C21.3377 (18)C17—H1720.9800
N1—C61.340 (2)C17—H1730.9800
N1—H10.84 (3)C18—H1810.9800
C2—C31.3810 (18)C18—H1820.9800
C2—H20.9500C18—H1830.9800
C3—C41.3913 (17)C21—C221.3978 (18)
C3—H30.9500C21—C261.3986 (18)
C4—C51.3981 (17)C22—C231.4048 (17)
C4—C71.5139 (17)C22—C271.5053 (18)
C5—C61.3720 (19)C23—C241.3892 (17)
C5—H50.9500C23—H230.9500
C6—H60.9500C24—C251.3991 (17)
C7—C241.5270 (17)C25—C261.3878 (17)
C7—C141.5293 (16)C25—H250.9500
C7—H71.0000C26—C281.5072 (18)
C11—C161.3950 (17)C27—H2710.9800
C11—C121.3969 (17)C27—H2720.9800
C12—C131.3958 (17)C27—H2730.9800
C12—C171.5088 (18)C28—H2810.9800
C13—C141.3988 (17)C28—H2820.9800
C13—H130.9500C28—H2830.9800
C14—C151.3903 (17)
C11—O1—H01113.5 (14)C11—C16—C18120.06 (11)
C21—O2—H02110.5 (16)C12—C17—H171109.5
C2—N1—C6122.65 (12)C12—C17—H172109.5
C2—N1—H1118.6 (15)H171—C17—H172109.5
C6—N1—H1118.8 (15)C12—C17—H173109.5
N1—C2—C3119.34 (13)H171—C17—H173109.5
N1—C2—H2120.3H172—C17—H173109.5
C3—C2—H2120.3C16—C18—H181109.5
C2—C3—C4120.19 (12)C16—C18—H182109.5
C2—C3—H3119.9H181—C18—H182109.5
C4—C3—H3119.9C16—C18—H183109.5
C3—C4—C5118.06 (11)H181—C18—H183109.5
C3—C4—C7123.03 (11)H182—C18—H183109.5
C5—C4—C7118.88 (11)O2—C21—C22122.60 (12)
C6—C5—C4119.98 (12)O2—C21—C26115.88 (12)
C6—C5—H5120.0C22—C21—C26121.53 (11)
C4—C5—H5120.0C21—C22—C23118.32 (12)
N1—C6—C5119.77 (12)C21—C22—C27121.14 (12)
N1—C6—H6120.1C23—C22—C27120.53 (12)
C5—C6—H6120.1C24—C23—C22121.40 (12)
C4—C7—C24111.83 (10)C24—C23—H23119.3
C4—C7—C14109.97 (10)C22—C23—H23119.3
C24—C7—C14116.38 (10)C23—C24—C25118.43 (11)
C4—C7—H7106.0C23—C24—C7124.13 (11)
C24—C7—H7106.0C25—C24—C7117.44 (10)
C14—C7—H7106.0C26—C25—C24121.99 (11)
O1—C11—C16115.46 (11)C26—C25—H25119.0
O1—C11—C12123.25 (11)C24—C25—H25119.0
C16—C11—C12121.29 (11)C25—C26—C21118.29 (11)
C13—C12—C11118.48 (11)C25—C26—C28121.07 (12)
C13—C12—C17120.94 (12)C21—C26—C28120.63 (11)
C11—C12—C17120.57 (11)C22—C27—H271109.5
C12—C13—C14121.63 (12)C22—C27—H272109.5
C12—C13—H13119.2H271—C27—H272109.5
C14—C13—H13119.2C22—C27—H273109.5
C15—C14—C13118.00 (11)H271—C27—H273109.5
C15—C14—C7122.39 (11)H272—C27—H273109.5
C13—C14—C7119.52 (11)C26—C28—H281109.5
C14—C15—C16122.12 (11)C26—C28—H282109.5
C14—C15—H15118.9H281—C28—H282109.5
C16—C15—H15118.9C26—C28—H283109.5
C15—C16—C11118.46 (11)H281—C28—H283109.5
C15—C16—C18121.48 (12)H282—C28—H283109.5
C5—C4—C7—C1475.36 (14)C4—C7—C24—C2564.67 (14)
C4—C7—C14—C1512.64 (16)C13—C14—C7—C2467.76 (15)
C3—C4—C7—C2428.52 (16)C14—C7—C24—C2311.40 (17)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···Br0.84 (3)2.46 (3)3.2090 (11)149.8 (19)
O1—H01···Bri0.83 (2)2.47 (2)3.1984 (10)147.5 (18)
O2—H02···Brii0.80 (2)2.70 (2)3.3745 (10)143 (2)
C2—H2···Briii0.953.103.4576 (13)104
C7—H7···Briv1.002.923.8791 (12)161
C17—H171···Brv0.983.053.9690 (15)157
C18—H181···Brvi0.983.133.8243 (15)129
Symmetry codes: (i) x+5/2, y1/2, z+1/2; (ii) x, y1, z; (iii) x+1, y+2, z; (iv) x+3/2, y1/2, z+1/2; (v) x+1/2, y+3/2, z+1/2; (vi) x+2, y+2, z.

Experimental details

(I)(II)
Crystal data
Chemical formulaC22H24NO2+·ClC22H24NO2+·Br
Mr369.87414.33
Crystal system, space groupMonoclinic, P21/nMonoclinic, P21/n
Temperature (K)120120
a, b, c (Å)8.6590 (2), 14.3920 (17), 15.7057 (12)8.7217 (4), 14.7461 (6), 15.4836 (6)
α, β, γ (°)90, 102.519 (14), 9090, 101.59 (1), 90
V3)1910.7 (3)1950.73 (14)
Z44
Radiation typeMo KαMo Kα
µ (mm1)0.222.12
Crystal size (mm)0.26 × 0.15 × 0.090.32 × 0.22 × 0.12
Data collection
DiffractometerBruker SMART 6000 CCD area-detector
diffractometer
Bruker APEX CCD area-detector
diffractometer
Absorption correctionIntegration
(XPREP in SHELXTL; Bruker, 2001)
Multi-scan
(SADABS; Bruker, 2003)
Tmin, Tmax0.953, 0.9840.803, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
21158, 4383, 3330 21226, 5943, 5263
Rint0.0580.017
(sin θ/λ)max1)0.6500.714
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.048, 0.142, 1.05 0.027, 0.070, 1.05
No. of reflections43835942
No. of parameters255256
H-atom treatmentH atoms treated by a mixture of independent and constrained refinementH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.65, 0.240.90, 0.23

Computer programs: SMART (Bruker, 2001), SMART, SAINT (Bruker, 2003), SAINT (Bruker, 2001), SAINT, SHELXTL (Bruker, 2001), SHELXTL.

Selected geometric parameters (Å, º) for (I) top
O1—C111.377 (2)N1—C61.340 (3)
O1—H010.81 (2)N1—H10.94 (3)
O2—C211.374 (2)C4—C71.514 (2)
O2—H020.84 (3)C7—C241.529 (2)
N1—C21.338 (2)C7—C141.533 (2)
C2—N1—C6122.11 (17)C4—C7—C14109.72 (14)
C4—C7—C24112.16 (14)C24—C7—C14115.71 (14)
Hydrogen-bond geometry (Å, º) for (I) top
D—H···AD—HH···AD···AD—H···A
N1—H1···Cl0.94 (3)2.19 (3)3.0371 (17)150 (2)
O1—H01···Cli0.81 (2)2.36 (3)3.0732 (15)147 (2)
O2—H02···Clii0.84 (3)2.45 (3)3.1990 (15)148 (2)
C2—H2···Cliii0.953.013.3813 (19)105
C7—H7···Cliv1.002.993.9568 (19)162
C17—H171···Clv0.983.023.956 (2)160
C18—H181···Clvi0.983.113.802 (2)129
Symmetry codes: (i) x+5/2, y1/2, z+1/2; (ii) x, y1, z; (iii) x+1, y+2, z; (iv) x+3/2, y1/2, z+1/2; (v) x+1/2, y+3/2, z+1/2; (vi) x+2, y+2, z.
Selected geometric parameters (Å, º) for (II) top
O1—C111.3718 (14)N1—C61.340 (2)
O1—H010.83 (2)N1—H10.84 (3)
O2—C211.3746 (15)C4—C71.5139 (17)
O2—H020.80 (2)C7—C241.5270 (17)
N1—C21.3377 (18)C7—C141.5293 (16)
C2—N1—C6122.65 (12)C4—C7—C14109.97 (10)
C4—C7—C24111.83 (10)C24—C7—C14116.38 (10)
Hydrogen-bond geometry (Å, º) for (II) top
D—H···AD—HH···AD···AD—H···A
N1—H1···Br0.84 (3)2.46 (3)3.2090 (11)149.8 (19)
O1—H01···Bri0.83 (2)2.47 (2)3.1984 (10)147.5 (18)
O2—H02···Brii0.80 (2)2.70 (2)3.3745 (10)143 (2)
C2—H2···Briii0.953.103.4576 (13)104
C7—H7···Briv1.002.923.8791 (12)161
C17—H171···Brv0.983.053.9690 (15)157
C18—H181···Brvi0.983.133.8243 (15)129
Symmetry codes: (i) x+5/2, y1/2, z+1/2; (ii) x, y1, z; (iii) x+1, y+2, z; (iv) x+3/2, y1/2, z+1/2; (v) x+1/2, y+3/2, z+1/2; (vi) x+2, y+2, z.
Corrected hydrogen-bond distances (Å) and angles (°) in (I) and (II) top
Calculated for idealized bond lengths N—H 1.01, O—H 0.97 and C—H 1.08 Å, as determined by neutron diffraction (Allen et al., 1987). X = Cl in (I) and Br in (II).
D—H···XD···ClH···ClD-H-ClD···BrH···BrD-H-Br
N1—H1···X3.037 (2)2.13 (3)149 (2)3.209 (1)2.33 (3)145 (2)
O1—H01···Xi3.073 (2)2.23 (3)145 (2)3.198 (1)2.35 (2)146 (2)
O2—H02···Xii3.199 (2)2.35 (3)147 (2)3.375 (1)2.61 (2)136 (2)
C7—H7···Xiii3.957 (2)2.921623.879 (1)2.84161 (2)
C17—H171···Xiv3.956 (2)2.931593.969 (1)2.97155 (2)
C18—H181···Xv3.802 (2)3.051273.824 (1)3.05130 (2)
Symmetry codes: (i) 5/2 − x, y − 1/2, 1/2 − z, (ii) x, y − 1, z, (iii) 3/2 − x, y − 1/2, 1/2 − z, (iv) x + 1/2, 3/2 − y, z + 1/2, (v) 2 − x, 2 − y, −z.
 

Acknowledgements

The authors thank the Council of Scientific and Industrial Research, New Delhi, India, for financial support (RSS) and Dr R. Kataky, Department of Chemistry, University of Durham, for helpful advice.

References

First citationAllen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1–19.  CrossRef Web of Science Google Scholar
First citationBeer, P. D. (1996). J. Chem. Soc. Chem. Commun. pp. 689–696.  CrossRef Google Scholar
First citationBianchi, A., Bowman-James, K. & Garcia-España, E. (1997). Editors. Supramolecular Chemistry of Anions. New York: Wiley–VCH.  Google Scholar
First citationBruker (2001). SMART (Version 5.625), SAINT (Version 6.02a) and SHELXTL (Version 6.12). Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationBruker (2003). SAINT (Version 6.45a) and SADABS (Version 2.10). Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationGale, P. A. (2000). Coord. Chem. Rev. 199, 181–233.  Web of Science CrossRef CAS Google Scholar
First citationGale, P. A. (2001). Coord. Chem. Rev. 213, 79–128.  Web of Science CrossRef CAS Google Scholar
First citationHasenknopf, B., Lehn, J. M., Boumediene, N., Dupont-Gervais, A., Van Dorsselar, A., Kniesel, B. & Fenske, D. (1997). J. Am. Chem. Soc. 119, 10956–10962.  CSD CrossRef CAS Web of Science Google Scholar
First citationHasenknopf, B., Lehn, J. M., Kniesel, B., Baum, G. & Fenske, D. (1996). Angew. Chem. Int. Ed. Engl. 35, 1838–1840.  CSD CrossRef CAS Web of Science Google Scholar
First citationIlioudis, C. A., Hancock, K. S. B., Georganopoulou, D. G. & Steed, J. W. (2000). New J. Chem. 24, 787–798.  Web of Science CSD CrossRef CAS Google Scholar
First citationLehn, J. M. (1995). Supramolecular Chemistry: Concepts and Perspectives. Weinheim: VCH.  Google Scholar
First citationMcArdle, C. P., Van, S., Jennings, M. C. & Puddephatt, R. J. (2002). J. Am. Chem. Soc. 124, 3959–3965.  Web of Science CSD CrossRef PubMed CAS Google Scholar
First citationPajewski, R., Ferdani, R., Schlesinger, P. H. & Gokel, G. W. (2004). Chem. Commun. pp. 160–161.  Web of Science CrossRef Google Scholar
First citationRowland, R. S. & Taylor, R. (1996). J. Phys. Chem. 100, 7384–7391.  CrossRef CAS Web of Science Google Scholar
First citationSchmidtchen, F. P. & Berger, M. (1997). Chem. Rev. 97, 1609–1646.  CrossRef PubMed CAS Web of Science Google Scholar
First citationSessler, J. L. Camiolo, S. & Gale, P. A. (2003). Coord. Chem. Rev. 240, 17–55.  Web of Science CrossRef CAS Google Scholar
First citationShannon, R. D. & Prewitt, C. T. (1969). Acta Cryst. B25, 925–946.  CrossRef CAS IUCr Journals Web of Science Google Scholar

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