organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 66| Part 7| July 2010| Pages o1843-o1844

2-Amino-4-methyl­pyridinium 3-chloro­benzoate

aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
*Correspondence e-mail: hkfun@usm.my

(Received 18 June 2010; accepted 23 June 2010; online 26 June 2010)

In the title salt, C6H9N2+·C7H4ClO2, the 2-amino-4-methyl­pyridinium cation is almost planar, with a maximum deviation of 0.010 (1) Å. In the crystal, the protonated N atom and the 2-amino group of the cation are hydrogen bonded to the carboxyl­ate O atoms of the anion via a pair of N—H⋯O hydrogen bonds, forming an R22(8) ring motif. The ion pairs are further connected via N—H⋯O and C—H⋯O hydrogen bonds, forming a two-dimensional network parallel to the bc plane.

Related literature

For details of non-covalent inter­actions, see: Remenar et al. (2003[Remenar, J. F., Morissette, S. L., Peterson, M. L., Moulton, B., MacPhee, J. M., GuzmaÅ, H. R. & Almarsson, O. È. (2003). J. Am. Chem. Soc. 125, 8456-8457.]); Aakeroÿ et al. (2001[Aakeroÿ, C. B., Beatty, A. M. & Helfrich, B. A. (2001). Angew. Chem. Int. Ed. 40, 3240-3242.]); Sokolov et al. (2006[Sokolov, A. N., FrisïcïcÅ, T. & MacGillivray, L. R. (2006). J. Am. Chem. Soc. 128, 2806-2807.]). For related structures, see: Kvick & Noordik (1977[Kvick, Å. & Noordik, J. (1977). Acta Cryst. B33, 2862-2866.]); Shen et al. (2008[Shen, H., Nie, J.-J. & Xu, D.-J. (2008). Acta Cryst. E64, o1129.]); Hemamalini & Fun (2010a[Hemamalini, M. & Fun, H.-K. (2010a). Acta Cryst. E66, o335.],b[Hemamalini, M. & Fun, H.-K. (2010b). Acta Cryst. E66, o781-o782.]). For details of hydrogen bonding, see: Jeffrey & Saenger (1991[Jeffrey, G. A. & Saenger, W. (1991). Hydrogen Bonding in Biological Structures. Berlin: Springer.]); Jeffrey (1997[Jeffrey, G. A. (1997). An Introduction to Hydrogen Bonding. Oxford University Press.]); Scheiner (1997[Scheiner, S. (1997). Hydrogen Bonding. A Theoretical Perspective. Oxford University Press.]). For hydrogen-bond motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]). For bond-length data, see: 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.]). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986[Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105-107.]).

[Scheme 1]

Experimental

Crystal data
  • C6H9N2+·C7H4ClO2

  • Mr = 264.70

  • Monoclinic, P 21

  • a = 7.9930 (6) Å

  • b = 6.8608 (5) Å

  • c = 11.2148 (9) Å

  • β = 93.526 (2)°

  • V = 613.84 (8) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.31 mm−1

  • T = 100 K

  • 0.28 × 0.17 × 0.10 mm

Data collection
  • Bruker APEXII DUO CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.919, Tmax = 0.971

  • 9325 measured reflections

  • 4207 independent reflections

  • 4076 reflections with I > 2σ(I)

  • Rint = 0.019

Refinement
  • R[F2 > 2σ(F2)] = 0.029

  • wR(F2) = 0.117

  • S = 1.22

  • 4207 reflections

  • 164 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.64 e Å−3

  • Δρmin = −0.54 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1860 Friedel pairs

  • Flack parameter: −0.01 (4)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1A⋯O1i 0.86 1.83 2.6921 (16) 175
N2—H2B⋯O2i 0.86 1.93 2.786 (2) 177
N2—H2C⋯O2ii 0.86 1.96 2.8146 (14) 173
C5—H5A⋯O1iii 0.93 2.50 3.1707 (13) 129
Symmetry codes: (i) x, y+1, z; (ii) [-x+1, y+{\script{1\over 2}}, -z+2]; (iii) [-x+1, y+{\script{1\over 2}}, -z+1].

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Recently, much attention has been devoted to the design and synthesis of supramolecular architectures assembled via various weak noncovalent interactions, such as hydrogen bonds, π···π stacking and C—H···π interactions (Remenar et al., 2003; Aakeroÿ et al., 2001; Sokolov et al., 2006). 2-Aminopyridine and its derivatives are used in the manufacture of pharmaceuticals, hair dyes and other dyes. They are often involved in hydrogen-bond interactions (Jeffrey & Saenger, 1991; Jeffrey, 1997; Scheiner, 1997). The crystal structures of 2-amino-4-methyl pyridine (Kvick & Noordik, 1977) and 2-amino-4-methylpyridinium 4-aminobenzoate (Shen et al., 2008) have been reported. We have recently reported the crystal structures of 2-amino-4-methylpyridinium 4-nitrobenzoate (Hemamalini & Fun, 2010a) and 2-Amino-4-methylpyridinium trifluoroacetate (Hemamalini & Fun, 2010b) from our laboratory. In continuation of our studies of pyridinium derivatives, the crystal structure determination of the title salt has been undertaken.

The asymmetric unit of the title compound, (Fig 1), contains a protonated 2-amino-4-methylpyridinium cation and a 3-chlorobenzoate anion. The 2-amino-4-methylpyridinium cation is planar, with a maximum deviation of 0.010 (1) Å for atom C1. The protonated N1 atom has lead to a slight increase in the C1—N1—C5 angle to 121.66 (11)°, compared to the corresponding angle of 117.3 (1)° in neutral 2-amino-4-methylpyridine (Kvick & Noordik, 1977). The bond lengths (Allen et al., 1987) and angles are normal.

In the crystal packing, (Fig. 2), the protonated N atom and 2-amino group (N2) is hydrogen-bonded to the carboxylate oxygen atoms (O1 and O2) via a pair of N—H···O hydrogen bonds leading to the formation of a R22(8) ring (Bernstein et al., 1995). Furthermore, these motifs are connected via N2—H2C···O2 and C5—H5A···O1 hydrogen bonds to form two-dimensional networks parallel to the bc-plane.

Related literature top

For details of non-covalent interactions, see: Remenar et al. (2003); Aakeroÿ et al. (2001); Sokolov et al. (2006). For related structures, see: Kvick & Noordik (1977); Shen et al. (2008); Hemamalini & Fun (2010a,b). For details of hydrogen bonding, see: Jeffrey & Saenger (1991); Jeffrey (1997); Scheiner (1997). For hydrogen-bond motifs, see: Bernstein et al. (1995). For bond-length data, see: Allen et al. (1987). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).

Experimental top

A hot methanol solution (20 ml) of 2-amino-4-methylpyridine (54 mg, Aldrich) and 3-chlorobenzoic acid (78 mg, Merck) were mixed and warmed over a heating magnetic-stirrer hotplate for a few minutes. The resulting solution was allowed to cool slowly at room temperature and colourless needles of (I) appeared after a few days.

Refinement top

All hydrogen atoms were positioned geometrically [C–H = 0.93 or 0.96 Å] and were refined using a riding model, with Uiso(H) = 1.2 or 1.5 Ueq(C). A rotating group model was used for the methyl group. 1860 Friedel pairs were used to determine the absolute configuration.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008; molecular graphics: SHELXTL (Sheldrick, 2008; software used to prepare material for publication: SHELXTL (Sheldrick, 2008 and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of (I). Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. The crystal packing of (I), showing hydrogen-bonded (dashed lines) 2D networks parallel to the bc-plane.
2-Amino-4-methylpyridinium 3-chlorobenzoate top
Crystal data top
C6H9N2+·C7H4ClO2F(000) = 276
Mr = 264.70Dx = 1.432 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ybCell parameters from 6601 reflections
a = 7.9930 (6) Åθ = 3.9–35.1°
b = 6.8608 (5) ŵ = 0.31 mm1
c = 11.2148 (9) ÅT = 100 K
β = 93.526 (2)°Needle, colourless
V = 613.84 (8) Å30.28 × 0.17 × 0.10 mm
Z = 2
Data collection top
Bruker APEXII DUO CCD
diffractometer
4207 independent reflections
Radiation source: fine-focus sealed tube4076 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.019
ϕ and ω scansθmax = 32.5°, θmin = 3.9°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 1212
Tmin = 0.919, Tmax = 0.971k = 1010
9325 measured reflectionsl = 1616
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.029H-atom parameters constrained
wR(F2) = 0.117 w = 1/[σ2(Fo2) + (0.0801P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.22(Δ/σ)max < 0.001
4207 reflectionsΔρmax = 0.64 e Å3
164 parametersΔρmin = 0.54 e Å3
1 restraintAbsolute structure: Flack (1983), 1860 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.01 (4)
Crystal data top
C6H9N2+·C7H4ClO2V = 613.84 (8) Å3
Mr = 264.70Z = 2
Monoclinic, P21Mo Kα radiation
a = 7.9930 (6) ŵ = 0.31 mm1
b = 6.8608 (5) ÅT = 100 K
c = 11.2148 (9) Å0.28 × 0.17 × 0.10 mm
β = 93.526 (2)°
Data collection top
Bruker APEXII DUO CCD
diffractometer
4207 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
4076 reflections with I > 2σ(I)
Tmin = 0.919, Tmax = 0.971Rint = 0.019
9325 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.029H-atom parameters constrained
wR(F2) = 0.117Δρmax = 0.64 e Å3
S = 1.22Δρmin = 0.54 e Å3
4207 reflectionsAbsolute structure: Flack (1983), 1860 Friedel pairs
164 parametersAbsolute structure parameter: 0.01 (4)
1 restraint
Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cl10.03584 (4)1.13218 (6)0.91629 (3)0.02460 (10)
O10.36548 (12)0.41445 (16)0.66474 (7)0.01744 (18)
O20.36855 (12)0.47553 (16)0.86099 (7)0.01876 (19)
C70.18473 (15)0.7570 (2)0.61091 (10)0.0158 (2)
H7A0.21310.67820.54780.019*
C80.09543 (15)0.9288 (2)0.58796 (11)0.0197 (2)
H8A0.06540.96480.50960.024*
C90.05103 (16)1.0466 (2)0.68188 (12)0.0195 (2)
H9A0.00781.16180.66710.023*
C100.09626 (15)0.9890 (2)0.79852 (10)0.0159 (2)
C110.18604 (14)0.8195 (2)0.82290 (10)0.0148 (2)
H11A0.21550.78380.90140.018*
C120.23182 (14)0.70259 (19)0.72825 (10)0.01258 (19)
C130.32902 (14)0.51628 (19)0.75345 (10)0.0131 (2)
N10.53373 (13)1.07928 (17)0.70756 (8)0.01350 (18)
H1A0.47861.18630.69790.016*
N20.53701 (13)1.1268 (3)0.91147 (8)0.0185 (2)
H2B0.48371.23440.89860.022*
H2C0.56381.09020.98350.022*
C10.57797 (14)1.01721 (19)0.82012 (10)0.0133 (2)
C20.66378 (14)0.8378 (2)0.83484 (10)0.0144 (2)
H2A0.69360.79190.91120.017*
C30.70348 (14)0.73057 (19)0.73661 (10)0.0141 (2)
C40.65921 (14)0.8046 (2)0.62099 (10)0.0152 (2)
H4A0.68780.73640.55350.018*
C50.57458 (14)0.9762 (2)0.60956 (9)0.0143 (2)
H5A0.54411.02390.53370.017*
C60.79035 (16)0.5371 (2)0.75110 (12)0.0195 (2)
H6A0.90160.54720.72390.029*
H6B0.72860.44040.70480.029*
H6C0.79640.50020.83380.029*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.02597 (15)0.02386 (18)0.02371 (15)0.00755 (12)0.00058 (10)0.00950 (12)
O10.0271 (4)0.0139 (4)0.0114 (3)0.0054 (3)0.0016 (3)0.0014 (3)
O20.0299 (4)0.0157 (5)0.0104 (3)0.0044 (4)0.0002 (3)0.0000 (3)
C70.0166 (4)0.0184 (6)0.0123 (4)0.0012 (4)0.0013 (3)0.0016 (4)
C80.0203 (5)0.0227 (7)0.0160 (5)0.0047 (5)0.0006 (4)0.0050 (5)
C90.0189 (5)0.0184 (7)0.0213 (5)0.0041 (4)0.0007 (4)0.0019 (5)
C100.0147 (4)0.0158 (6)0.0173 (4)0.0005 (4)0.0016 (3)0.0023 (4)
C110.0159 (4)0.0148 (6)0.0135 (4)0.0000 (4)0.0007 (3)0.0009 (4)
C120.0131 (4)0.0126 (5)0.0121 (4)0.0009 (4)0.0013 (3)0.0007 (4)
C130.0175 (4)0.0108 (5)0.0109 (4)0.0016 (4)0.0013 (3)0.0000 (4)
N10.0177 (4)0.0123 (5)0.0106 (4)0.0005 (3)0.0009 (3)0.0017 (3)
N20.0292 (5)0.0162 (5)0.0100 (4)0.0049 (4)0.0009 (3)0.0003 (4)
C10.0164 (4)0.0130 (5)0.0104 (4)0.0015 (4)0.0017 (3)0.0018 (4)
C20.0175 (4)0.0135 (6)0.0123 (4)0.0005 (4)0.0012 (3)0.0027 (4)
C30.0138 (4)0.0133 (6)0.0152 (4)0.0010 (4)0.0016 (3)0.0007 (4)
C40.0161 (4)0.0164 (6)0.0130 (4)0.0008 (4)0.0012 (3)0.0014 (4)
C50.0169 (4)0.0161 (6)0.0099 (4)0.0021 (4)0.0012 (3)0.0001 (4)
C60.0199 (5)0.0158 (6)0.0228 (5)0.0032 (4)0.0024 (4)0.0010 (4)
Geometric parameters (Å, º) top
Cl1—C101.7383 (13)N1—H1A0.8600
O1—C131.2643 (14)N2—C11.3280 (18)
O2—C131.2593 (14)N2—H2B0.8600
C7—C81.3934 (19)N2—H2C0.8600
C7—C121.3972 (16)C1—C21.4138 (18)
C7—H7A0.9300C2—C31.3779 (16)
C8—C91.3909 (19)C2—H2A0.9300
C8—H8A0.9300C3—C41.4170 (16)
C9—C101.3927 (17)C3—C61.5019 (19)
C9—H9A0.9300C4—C51.3599 (18)
C10—C111.3849 (19)C4—H4A0.9300
C11—C121.3968 (17)C5—H5A0.9300
C11—H11A0.9300C6—H6A0.9600
C12—C131.5134 (18)C6—H6B0.9600
N1—C11.3582 (14)C6—H6C0.9600
N1—C51.3636 (15)
C8—C7—C12120.35 (12)C1—N2—H2B120.0
C8—C7—H7A119.8C1—N2—H2C120.0
C12—C7—H7A119.8H2B—N2—H2C120.0
C9—C8—C7120.21 (11)N2—C1—N1118.49 (12)
C9—C8—H8A119.9N2—C1—C2122.93 (11)
C7—C8—H8A119.9N1—C1—C2118.57 (11)
C8—C9—C10118.87 (12)C3—C2—C1120.36 (10)
C8—C9—H9A120.6C3—C2—H2A119.8
C10—C9—H9A120.6C1—C2—H2A119.8
C11—C10—C9121.68 (12)C2—C3—C4118.91 (11)
C11—C10—Cl1119.30 (9)C2—C3—C6120.86 (11)
C9—C10—Cl1119.01 (10)C4—C3—C6120.22 (11)
C10—C11—C12119.26 (11)C5—C4—C3119.42 (11)
C10—C11—H11A120.4C5—C4—H4A120.3
C12—C11—H11A120.4C3—C4—H4A120.3
C11—C12—C7119.63 (12)C4—C5—N1121.04 (11)
C11—C12—C13119.90 (10)C4—C5—H5A119.5
C7—C12—C13120.47 (11)N1—C5—H5A119.5
O2—C13—O1125.07 (12)C3—C6—H6A109.5
O2—C13—C12117.52 (10)C3—C6—H6B109.5
O1—C13—C12117.41 (10)H6A—C6—H6B109.5
C1—N1—C5121.66 (11)C3—C6—H6C109.5
C1—N1—H1A119.2H6A—C6—H6C109.5
C5—N1—H1A119.2H6B—C6—H6C109.5
C12—C7—C8—C90.62 (19)C11—C12—C13—O1179.10 (11)
C7—C8—C9—C100.5 (2)C7—C12—C13—O10.27 (16)
C8—C9—C10—C110.9 (2)C5—N1—C1—N2178.68 (11)
C8—C9—C10—Cl1178.18 (10)C5—N1—C1—C22.06 (17)
C9—C10—C11—C120.32 (18)N2—C1—C2—C3179.79 (12)
Cl1—C10—C11—C12178.81 (9)N1—C1—C2—C30.98 (17)
C10—C11—C12—C70.79 (17)C1—C2—C3—C40.97 (17)
C10—C11—C12—C13179.62 (10)C1—C2—C3—C6178.29 (10)
C8—C7—C12—C111.26 (18)C2—C3—C4—C51.91 (17)
C8—C7—C12—C13179.91 (11)C6—C3—C4—C5177.35 (11)
C11—C12—C13—O21.50 (17)C3—C4—C5—N10.90 (17)
C7—C12—C13—O2179.67 (11)C1—N1—C5—C41.13 (17)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O1i0.861.832.6921 (16)175
N2—H2B···O2i0.861.932.786 (2)177
N2—H2C···O2ii0.861.962.8146 (14)173
C5—H5A···O1iii0.932.503.1707 (13)129
Symmetry codes: (i) x, y+1, z; (ii) x+1, y+1/2, z+2; (iii) x+1, y+1/2, z+1.

Experimental details

Crystal data
Chemical formulaC6H9N2+·C7H4ClO2
Mr264.70
Crystal system, space groupMonoclinic, P21
Temperature (K)100
a, b, c (Å)7.9930 (6), 6.8608 (5), 11.2148 (9)
β (°) 93.526 (2)
V3)613.84 (8)
Z2
Radiation typeMo Kα
µ (mm1)0.31
Crystal size (mm)0.28 × 0.17 × 0.10
Data collection
DiffractometerBruker APEXII DUO CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.919, 0.971
No. of measured, independent and
observed [I > 2σ(I)] reflections
9325, 4207, 4076
Rint0.019
(sin θ/λ)max1)0.756
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.029, 0.117, 1.22
No. of reflections4207
No. of parameters164
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.64, 0.54
Absolute structureFlack (1983), 1860 Friedel pairs
Absolute structure parameter0.01 (4)

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008), SHELXTL (Sheldrick, 2008 and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O1i0.861.832.6921 (16)175
N2—H2B···O2i0.861.932.786 (2)177
N2—H2C···O2ii0.861.962.8146 (14)173
C5—H5A···O1iii0.932.503.1707 (13)129
Symmetry codes: (i) x, y+1, z; (ii) x+1, y+1/2, z+2; (iii) x+1, y+1/2, z+1.
 

Footnotes

Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

MH and HKF thank the Malaysian Government and Universiti Sains Malaysia for the Research University Golden Goose grant No. 1001/PFIZIK/811012. MH also thanks Universiti Sains Malaysia for a post-doctoral research fellowship.

References

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Volume 66| Part 7| July 2010| Pages o1843-o1844
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