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

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ISSN: 2056-9890

2,7-Di­bromo-9,9-bis­­[(pyridin-1-ium-4-yl)meth­yl]fluorene dinitrate

aMicroscale Science Institute, Weifang University, Weifang 261061, People's Republic of China, and bNew Materials and Function Coordination Chemistry Laboratory, Qingdao University of Science and Technology, Qingdao 266042, People's Republic of China
*Correspondence e-mail: ffjian2008@163.com

(Received 13 November 2009; accepted 21 December 2009; online 9 January 2010)

In the title compound, C25H20Br2N22+·2NO3, the cation lies on a twofold rotation axis which imposes disorder of the dibromo­fluorene unit. In addition, the unique nitrate anion is disordered over two general sites of equal occupancy. The crystal structure is stabilized by inter­molecular N—H⋯O hydrogen bonds.

Related literature

For applications of bipyridine derivatives, see: Varughese & Pedireddi (2005[Varughese, S. & Pedireddi, V. R. (2005). Chem. Commun. pp. 1824-1836.], 2006[Varughese, S. & Pedireddi, V. R. (2006). Chem. Eur. J. 12, 1597-1600.]); Pedireddi & Lekshmi (2004[Pedireddi, V. R. & Lekshmi, N. S. (2004). Tetrahedron Lett. 45, 1903-1905.]); Friscic & MacGillivray (2005[Friscic, T. & MacGillivray, L. R. (2005). Chem. Commun. pp. 5748-5750.]).

[Scheme 1]

Experimental

Crystal data
  • C25H20Br2N22+·2NO3

  • Mr = 632.27

  • Orthorhombic, F d d 2

  • a = 14.874 (3) Å

  • b = 33.592 (7) Å

  • c = 10.720 (2) Å

  • V = 5356.2 (18) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 3.07 mm−1

  • T = 293 K

  • 0.25 × 0.20 × 0.18 mm

Data collection
  • Bruker SMART CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.514, Tmax = 0.608

  • 12890 measured reflections

  • 3053 independent reflections

  • 1355 reflections with I > 2σ(I)

  • Rint = 0.065

Refinement
  • R[F2 > 2σ(F2)] = 0.041

  • wR(F2) = 0.114

  • S = 0.91

  • 3053 reflections

  • 238 parameters

  • 77 restraints

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

  • Δρmax = 0.20 e Å−3

  • Δρmin = −0.18 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1443 Friedel pairs

  • Flack parameter: 0.002 (14)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1N⋯O2i 0.87 (5) 1.85 (5) 2.72 (2) 170 (4)
N1—H1N⋯O2Ai 0.87 (5) 1.92 (5) 2.73 (2) 154 (4)
Symmetry code: (i) [-x+{\script{3\over 2}}, -y+1, z+{\script{1\over 2}}].

Data collection: SMART (Bruker, 1997[Bruker (1997). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 1997[Bruker (1997). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Supporting information


Comment top

Bipyridine compounds have been studied as spacer molecules both in organic and organic-inorganic hybrid complexes (Varughese & Pedireddi, 2005,2006) Their ability to form intermolecular hydrogen bonds is of particular interest (Pedireddi & Lekshmi, 2004; Friscic & MacGillivray, 2005). We present herein the crystal structure of the titlecompound. The asymmetric unit of the title compund is shown in Fig. 1. The cation moleclue lies on a twofold rotation axis about which the dibromofluorene moiety is disordered. Atom C1 lies on the twofold rotation axis. In addtion, the unique nitrate anion is disodered over two general sites with equall occupancies. The crystal structure is stabilized by intermoecular N-H···O hydrogen bonds.

Related literature top

For applications of bipyridine derivatives, see: Varughese & Pedireddi (2005, 2006); Pedireddi & Lekshmi (2004); Friscic & MacGillivray (2005).

Experimental top

To a warm solution of 2,7-dibromo-9,9-(4-pyridyl-methyl)fluorene [2.55 g, 5.0 mmol] in EtOH (50 ml), HNO3(10.0 mmol) was added dropwise with stirring. The mixture turned clear yellow. 1 h later, the yellow solution was filtered, and the filtrate was evaporated at room temperature in air. Three days later, crystals suitable for an X-ray structure determination were obtained.

Refinement top

H atoms were fixed geometrically and allowed to ride on their attached atoms, with C—H distances = 0.93-0.97 Å, and with Uiso=1.2Ueq(C). The H atom bonded to N1 was refined independently with an isotropic displacement parameter. The occupancies of the disorder components of the nitrate anion were intially refined but then fixed at 0.50:0.50.

Structure description top

Bipyridine compounds have been studied as spacer molecules both in organic and organic-inorganic hybrid complexes (Varughese & Pedireddi, 2005,2006) Their ability to form intermolecular hydrogen bonds is of particular interest (Pedireddi & Lekshmi, 2004; Friscic & MacGillivray, 2005). We present herein the crystal structure of the titlecompound. The asymmetric unit of the title compund is shown in Fig. 1. The cation moleclue lies on a twofold rotation axis about which the dibromofluorene moiety is disordered. Atom C1 lies on the twofold rotation axis. In addtion, the unique nitrate anion is disodered over two general sites with equall occupancies. The crystal structure is stabilized by intermoecular N-H···O hydrogen bonds.

For applications of bipyridine derivatives, see: Varughese & Pedireddi (2005, 2006); Pedireddi & Lekshmi (2004); Friscic & MacGillivray (2005).

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound showing 30% probability displacement ellipsoids. The disorder is not shown but thinner bonds show the areas where disorder occurs.
2,7-Dibromo-9,9-bis[(pyridin-1-ium-4-yl)methyl]fluorene dinitrate top
Crystal data top
C25H20Br2N22+·2NO3F(000) = 2528
Mr = 632.27Dx = 1.568 Mg m3
Orthorhombic, Fdd2Mo Kα radiation, λ = 0.71073 Å
Hall symbol: F 2 -2dCell parameters from 2016 reflections
a = 14.874 (3) Åθ = 3.3–27.9°
b = 33.592 (7) ŵ = 3.07 mm1
c = 10.720 (2) ÅT = 293 K
V = 5356.2 (18) Å3Block, yellow
Z = 80.25 × 0.20 × 0.18 mm
Data collection top
Bruker SMART CCD
diffractometer
3053 independent reflections
Radiation source: fine-focus sealed tube1355 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.065
φ scans and ω scans with κ offsetsθmax = 27.5°, θmin = 3.0°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 1819
Tmin = 0.514, Tmax = 0.608k = 4342
12890 measured reflectionsl = 1313
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)] = 0.041H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.114 w = 1/[σ2(Fo2) + (0.0494P)2]
where P = (Fo2 + 2Fc2)/3
S = 0.91(Δ/σ)max < 0.001
3053 reflectionsΔρmax = 0.20 e Å3
238 parametersΔρmin = 0.18 e Å3
77 restraintsAbsolute structure: Flack (1983), 1443 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.002 (14)
Crystal data top
C25H20Br2N22+·2NO3V = 5356.2 (18) Å3
Mr = 632.27Z = 8
Orthorhombic, Fdd2Mo Kα radiation
a = 14.874 (3) ŵ = 3.07 mm1
b = 33.592 (7) ÅT = 293 K
c = 10.720 (2) Å0.25 × 0.20 × 0.18 mm
Data collection top
Bruker SMART CCD
diffractometer
3053 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
1355 reflections with I > 2σ(I)
Tmin = 0.514, Tmax = 0.608Rint = 0.065
12890 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.041H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.114Δρmax = 0.20 e Å3
S = 0.91Δρmin = 0.18 e Å3
3053 reflectionsAbsolute structure: Flack (1983), 1443 Friedel pairs
238 parametersAbsolute structure parameter: 0.002 (14)
77 restraints
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.

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 > 2sigma(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*/UeqOcc. (<1)
Br10.5373 (4)0.34967 (12)1.0031 (6)0.177 (2)0.50
Br20.4644 (3)0.66079 (12)0.9441 (5)0.1266 (12)0.50
C10.50000.50000.8526 (6)0.0493 (14)
C20.5086 (13)0.4687 (4)0.9446 (10)0.074 (3)0.50
C30.5195 (12)0.4279 (4)0.9302 (8)0.082 (3)0.50
H3A0.52150.41680.85080.099*0.50
C40.5274 (9)0.4036 (3)1.0347 (11)0.085 (3)0.50
C50.5244 (7)0.4202 (2)1.1534 (9)0.086 (3)0.50
H5A0.52970.40391.22330.103*0.50
C60.5136 (7)0.4610 (3)1.1677 (9)0.085 (3)0.50
H6A0.51160.47211.24720.101*0.50
C70.5057 (10)0.4853 (2)1.0633 (12)0.074 (3)0.50
C80.4931 (10)0.5280 (2)1.0631 (10)0.066 (2)0.50
C90.4851 (7)0.5582 (2)1.1511 (8)0.075 (2)0.50
H9A0.48570.55211.23570.090*0.50
C100.4761 (7)0.5975 (2)1.1126 (8)0.077 (2)0.50
H10A0.47080.61771.17150.093*0.50
C110.4752 (8)0.6066 (3)0.9861 (8)0.067 (2)0.50
C120.4832 (11)0.5765 (3)0.8981 (7)0.063 (2)0.50
H12A0.48260.58260.81350.075*0.50
C130.4922 (12)0.5371 (3)0.9366 (9)0.058 (2)0.50
N10.8313 (2)0.53409 (10)0.9320 (5)0.0682 (11)
C140.58325 (19)0.50368 (11)0.7642 (5)0.0510 (9)
H14A0.59190.47850.72170.061*
H14B0.57050.52370.70130.061*
C150.6693 (2)0.51471 (10)0.8298 (4)0.0467 (9)
C160.7043 (2)0.55303 (12)0.8175 (6)0.0694 (14)
H16A0.67220.57240.77440.083*
C170.7869 (3)0.56209 (14)0.8696 (6)0.0766 (15)
H17A0.81110.58750.86100.092*
C180.8004 (2)0.49768 (12)0.9466 (6)0.0690 (13)
H18A0.83410.47900.99000.083*
C190.7187 (2)0.48735 (11)0.8980 (5)0.0589 (11)
H19A0.69630.46180.91080.071*
O10.5248 (7)0.3942 (3)0.4656 (13)0.111 (4)0.50
O20.4986 (12)0.4542 (5)0.5171 (11)0.045 (3)0.50
O30.4155 (14)0.4101 (6)0.5905 (15)0.076 (4)0.50
N20.4807 (2)0.41997 (11)0.52359 (13)0.0733 (12)
O1A0.5534 (7)0.4013 (4)0.5514 (14)0.151 (7)0.50
O2A0.4890 (13)0.4546 (6)0.4700 (11)0.055 (3)0.50
O3A0.4017 (12)0.4069 (6)0.5454 (15)0.060 (3)0.50
H1N0.883 (3)0.5389 (11)0.968 (5)0.078 (13)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.170 (2)0.098 (2)0.262 (6)0.0198 (17)0.038 (3)0.097 (3)
Br20.1092 (12)0.0779 (15)0.193 (4)0.0056 (9)0.0114 (15)0.0480 (15)
C10.037 (2)0.063 (3)0.048 (4)0.002 (2)0.0000.000
C20.050 (5)0.108 (6)0.064 (5)0.002 (5)0.008 (5)0.028 (5)
C30.061 (5)0.113 (6)0.073 (6)0.001 (5)0.012 (5)0.034 (5)
C40.073 (5)0.111 (5)0.071 (6)0.003 (5)0.008 (5)0.041 (5)
C50.079 (5)0.109 (6)0.070 (5)0.002 (4)0.004 (4)0.034 (5)
C60.072 (4)0.114 (6)0.068 (5)0.005 (5)0.005 (4)0.030 (5)
C70.052 (4)0.111 (6)0.057 (5)0.001 (5)0.004 (4)0.032 (5)
C80.057 (4)0.094 (5)0.048 (5)0.007 (4)0.002 (4)0.023 (4)
C90.073 (4)0.097 (5)0.055 (5)0.000 (4)0.005 (4)0.025 (4)
C100.074 (4)0.098 (5)0.060 (5)0.001 (4)0.003 (4)0.021 (4)
C110.060 (4)0.085 (4)0.056 (5)0.001 (4)0.003 (4)0.028 (4)
C120.052 (4)0.078 (4)0.058 (5)0.001 (4)0.000 (4)0.019 (4)
C130.047 (4)0.079 (4)0.049 (5)0.002 (4)0.002 (4)0.018 (4)
N10.0453 (18)0.082 (3)0.078 (3)0.0047 (17)0.0146 (19)0.004 (2)
C140.0398 (15)0.064 (2)0.049 (3)0.0031 (16)0.0002 (16)0.0011 (19)
C150.0409 (17)0.0531 (19)0.046 (3)0.0005 (15)0.0012 (17)0.0044 (18)
C160.052 (2)0.059 (2)0.097 (4)0.0097 (17)0.015 (2)0.016 (2)
C170.057 (2)0.069 (3)0.104 (5)0.0135 (19)0.020 (2)0.004 (3)
C180.052 (2)0.073 (3)0.082 (4)0.0064 (18)0.016 (2)0.007 (3)
C190.049 (2)0.056 (2)0.072 (3)0.0011 (16)0.0079 (19)0.003 (2)
O10.090 (8)0.061 (4)0.182 (13)0.012 (5)0.057 (7)0.000 (7)
O20.055 (6)0.045 (4)0.036 (8)0.003 (3)0.001 (6)0.004 (6)
O30.085 (9)0.075 (5)0.068 (12)0.030 (5)0.023 (7)0.023 (8)
N20.061 (2)0.063 (3)0.096 (4)0.0058 (19)0.029 (2)0.002 (2)
O1A0.064 (5)0.102 (8)0.29 (2)0.016 (5)0.025 (8)0.086 (11)
O2A0.049 (4)0.072 (5)0.043 (9)0.002 (3)0.004 (6)0.012 (7)
O3A0.051 (5)0.078 (6)0.051 (9)0.013 (4)0.005 (5)0.018 (6)
Geometric parameters (Å, º) top
Br1—C41.849 (9)C11—C121.3900
Br2—C111.881 (9)C12—C131.3900
C1—C2i1.446 (9)C12—H12A0.9300
C1—C21.446 (9)N1—C181.316 (5)
C1—C131.543 (8)N1—C171.330 (5)
C1—C13i1.543 (9)N1—H1N0.87 (5)
C1—C14i1.564 (5)C14—C151.506 (5)
C1—C141.564 (5)C14—H14A0.9700
C2—C31.3900C14—H14B0.9700
C2—C71.3900C15—C191.386 (5)
C3—C41.3900C15—C161.395 (5)
C3—H3A0.9300C16—C171.384 (6)
C4—C51.3900C16—H16A0.9300
C5—C61.3900C17—H17A0.9300
C5—H5A0.9300C18—C191.366 (5)
C6—C71.3900C18—H18A0.9300
C6—H6A0.9300C19—H19A0.9300
C7—C81.447 (9)O1—N21.252 (11)
C8—C91.3900O2—N21.182 (19)
C8—C131.3900O3—N21.25 (2)
C9—C101.3900N2—O3A1.28 (2)
C9—H9A0.9300N2—O1A1.284 (11)
C10—C111.3900N2—O2A1.30 (2)
C10—H10A0.9300
C2i—C1—C294.1 (12)C11—C12—C13120.0
C2—C1—C13101.3 (5)C11—C12—H12A120.0
C2i—C1—C13i101.3 (6)C13—C12—H12A120.0
C13—C1—C13i108.6 (13)C12—C13—C8120.0
C2i—C1—C14i113.6 (7)C12—C13—C1127.0 (7)
C2—C1—C14i115.2 (7)C8—C13—C1112.9 (7)
C13—C1—C14i111.0 (7)C18—N1—C17122.9 (4)
C13i—C1—C14i110.4 (11)C18—N1—H1N115 (3)
C2i—C1—C14115.2 (7)C17—N1—H1N122 (3)
C2—C1—C14113.6 (7)C15—C14—C1114.1 (4)
C13—C1—C14110.4 (6)C15—C14—H14A108.7
C13i—C1—C14111.0 (11)C1—C14—H14A108.7
C14i—C1—C14105.4 (5)C15—C14—H14B108.7
C3—C2—C7120.0C1—C14—H14B108.7
C3—C2—C1130.7 (9)H14A—C14—H14B107.6
C7—C2—C1109.3 (9)C19—C15—C16117.6 (3)
C2—C3—C4120.0C19—C15—C14122.3 (3)
C2—C3—H3A120.0C16—C15—C14120.0 (3)
C4—C3—H3A120.0C17—C16—C15119.8 (4)
C3—C4—C5120.0C17—C16—H16A120.1
C3—C4—Br1115.7 (7)C15—C16—H16A120.1
C5—C4—Br1124.2 (7)N1—C17—C16119.2 (4)
C6—C5—C4120.0N1—C17—H17A120.4
C6—C5—H5A120.0C16—C17—H17A120.4
C4—C5—H5A120.0N1—C18—C19120.1 (4)
C7—C6—C5120.0N1—C18—H18A119.9
C7—C6—H6A120.0C19—C18—H18A119.9
C5—C6—H6A120.0C18—C19—C15120.3 (3)
C6—C7—C2120.0C18—C19—H19A119.8
C6—C7—C8126.5 (11)C15—C19—H19A119.8
C2—C7—C8113.5 (11)O2—N2—O3117.7 (13)
C9—C8—C13120.0O2—N2—O1121.8 (11)
C9—C8—C7137.2 (10)O3—N2—O1120.5 (11)
C13—C8—C7102.8 (10)O2—N2—O3A123.6 (14)
C10—C9—C8120.0O1—N2—O3A109.5 (9)
C10—C9—H9A120.0O2—N2—O1A107.4 (9)
C8—C9—H9A120.0O3—N2—O1A113.0 (11)
C9—C10—C11120.0O3A—N2—O1A124.4 (11)
C9—C10—H10A120.0O3—N2—O2A124.2 (15)
C11—C10—H10A120.0O1—N2—O2A110.5 (10)
C12—C11—C10120.0O3A—N2—O2A118.4 (13)
C12—C11—Br2123.4 (5)O1A—N2—O2A117.2 (11)
C10—C11—Br2116.6 (5)
Symmetry code: (i) x+1, y+1, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O2ii0.87 (5)1.85 (5)2.72 (2)170 (4)
N1—H1N···O2Aii0.87 (5)1.92 (5)2.73 (2)154 (4)
Symmetry code: (ii) x+3/2, y+1, z+1/2.

Experimental details

Crystal data
Chemical formulaC25H20Br2N22+·2NO3
Mr632.27
Crystal system, space groupOrthorhombic, Fdd2
Temperature (K)293
a, b, c (Å)14.874 (3), 33.592 (7), 10.720 (2)
V3)5356.2 (18)
Z8
Radiation typeMo Kα
µ (mm1)3.07
Crystal size (mm)0.25 × 0.20 × 0.18
Data collection
DiffractometerBruker SMART CCD
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.514, 0.608
No. of measured, independent and
observed [I > 2σ(I)] reflections
12890, 3053, 1355
Rint0.065
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.041, 0.114, 0.91
No. of reflections3053
No. of parameters238
No. of restraints77
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.20, 0.18
Absolute structureFlack (1983), 1443 Friedel pairs
Absolute structure parameter0.002 (14)

Computer programs: SMART (Bruker, 1997), SAINT (Bruker, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O2i0.87 (5)1.85 (5)2.72 (2)170 (4)
N1—H1N···O2Ai0.87 (5)1.92 (5)2.73 (2)154 (4)
Symmetry code: (i) x+3/2, y+1, z+1/2.
 

Acknowledgements

The authors would like to thank the National Natural Science Foundation of Shandong (Y2007B14, Y2008B29) and Weifang University for research grants.

References

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