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

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ISSN: 2056-9890

N,N′-[4,4′-Methyl­enebis(4,1-phenyl­ene)]bis­­(2,6-di­fluoro­benzamide)

aSchool of Pharmaceutical Sciences, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, bVirginia Commonwealth University, Chemistry School, USA, Malaysia, and cX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
*Correspondence e-mail: hkfun@usm.my

(Received 21 June 2011; accepted 22 June 2011; online 30 June 2011)

The complete mol­ecule of the title compound, C27H18F4N2O2, is generated by crystallographic twofold symmetry, with one C atom lying on the rotation axis. The dihedral angle between fluoro-substituted phenyl ring and the adjacent benzene ring is 10.37 (5)°. In the crystal, mol­ecules are connected by N—H⋯O and C—H⋯F hydrogen bonds, resulting in supra­molecular chains propagating along the c direction.

Related literature

For applications of benzamide derivatives, see: Ashwood et al. (1990[Ashwood, V. A., Cassidy, F., Coldwell, M. C., Evans, J. M., Hamilton, T. C., Howlett, D. R., Smith, D. M. & Stemp, G. (1990). J. Med. Chem. 33, 2667-2672.]); Kees et al. (1989[Kees, K. L., Cheeseman, R. S., Prozialeck, D. H. & Steiner, K. E. (1989). J. Med. Chem. 32, 11-13.]); Ragavan et al. (2010[Ragavan, R. V., Vijayakumar, V. & Suchetha Kumari, N. (2010). Eur. J. Med. Chem. 43, 1173-1180.]); Carmellino et al. (1994[Carmellino, M. L., Pagani, G., Pregnolato, M., Terreni, M. & Pastoni, F. (1994). Eur. J. Med. Chem. 29, 743-751.]); Rauko et al. (2001[Rauko, P., Novotny, L., Dovinova, I., Hunakova, L., Szekeres, T. & Jayaram, H. N. (2001). Eur. J. Pharm. Sci. 12, 387-394.]). For a related structure, see: Cronin et al. (2000[Cronin, L., Adams, D. A., Nightingale, D. J. & Clark, J. H. (2000). Acta Cryst. C56, 244-245.]). 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
  • C27H18F4N2O2

  • Mr = 478.43

  • Monoclinic, C 2/c

  • a = 42.0478 (10) Å

  • b = 5.2980 (1) Å

  • c = 9.5643 (2) Å

  • β = 92.522 (2)°

  • V = 2128.57 (8) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.12 mm−1

  • T = 100 K

  • 0.48 × 0.38 × 0.05 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 = 0.946, Tmax = 0.994

  • 26445 measured reflections

  • 3871 independent reflections

  • 3172 reflections with I > 2σ(I)

  • Rint = 0.031

Refinement
  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.114

  • S = 1.06

  • 3871 reflections

  • 163 parameters

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

  • Δρmax = 0.43 e Å−3

  • Δρmin = −0.21 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1N1⋯O1i 0.841 (15) 2.078 (15) 2.8811 (11) 159.4 (14)
C9—H9A⋯F1ii 0.95 2.41 3.2318 (11) 145
Symmetry codes: (i) [x, -y+2, z-{\script{1\over 2}}]; (ii) [x, -y+2, z+{\script{1\over 2}}].

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

A number of benzamide derivatives were reported to possess anti-hypertensive (Ashwood et al., 1990), anti-diabetic (Kees et al., 1989), anti-bacterial (Ragavan et al., 2010), anti-fungal (Carmellino et al., 1994) and anti-cancer (Rauko et al., 2001) activities. As a part of our study on the synthesis of new fluorine- containing compounds with possible biological activities, we report here the crystal structure of the title compound, (I).

The asymmetric unit of the title compound, (Fig. 1), consists of a half molecule of N,N'-(4,4'-methylenebis(4,1-phenylene))bis (2,6-difluorobenzamide), which has a twofold symmetry and it adopts an E, E conformation. The dihedral angle between fluoro- substituted phenyl (C1–C6) rings and benzene (C8–13) ring is 10.37 (5)°. All bond lengths and angles are comparable to values observed in a closely related benzamide structure (Cronin et al., 2000).

In the crystal structure (Fig. 2), the adjacent molecules are connected via N1—H1N1..O1 and C9—H9A···F1 (Table 1) hydrogen bonds forming one-dimensional supramolecular chains along the c-axis.

Related literature top

For applications of benzamide derivatives, see: Ashwood et al. (1990); Kees et al. (1989); Ragavan et al. (2010); Carmellino et al. (1994); Rauko et al. (2001). For a related structure, see: Cronin et al. (2000). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).

Experimental top

In a round bottom flask, 25ml of tetrahydrofuran (THF) was mixed with 4,4'-diaminodiphenylmethane (0.01 mol,2 g) with stirring. Drops of 2,6-Difluorobenzylchloride (0.02 mol, 3.4 g ) which was dissolved in THF was then added. The mixture was refluxed for 30 min and the yellow precipitate formed was filtered and washed with alkaline water, then with toluene and further washed with dilute hydrochloric acid. The precipate was dissolved in methanol at room temperature yielding colourless plates of (I).

Refinement top

Atom H1N1 was located from a difference Fourier maps and refined freely [N–H = 0.842 (15) Å]. The remaining H atoms were positioned geometrically [C–H = 0.95–0.9601 Å] and were refined using a riding model, with Uiso(H) = 1.2 Ueq(C). The highest residual electron density peak is located at 0.61 Å from C6 and the deepest hole 0.64 Å located at from C1.

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 the title compound, showing 50% probability displacement ellipsoids.
[Figure 2] Fig. 2. A view of a one-dimensional supramolecular chain along the c-axis
N-{4-[4-(2,6-difluorobenzamido)benzyl]phenyl}-2,6-difluorobenzamide top
Crystal data top
C27H18F4N2O2F(000) = 984
Mr = 478.43Dx = 1.493 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 8910 reflections
a = 42.0478 (10) Åθ = 2.9–32.5°
b = 5.2980 (1) ŵ = 0.12 mm1
c = 9.5643 (2) ÅT = 100 K
β = 92.522 (2)°Plate, colourless
V = 2128.57 (8) Å30.48 × 0.38 × 0.05 mm
Z = 4
Data collection top
Bruker APEXII DUO CCD
diffractometer
3871 independent reflections
Radiation source: fine-focus sealed tube3172 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.031
ϕ and ω scansθmax = 32.6°, θmin = 1.9°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 6363
Tmin = 0.946, Tmax = 0.994k = 77
26445 measured reflectionsl = 1414
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)] = 0.040Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.114H atoms treated by a mixture of independent and constrained refinement
S = 1.06 w = 1/[σ2(Fo2) + (0.0569P)2 + 1.3081P]
where P = (Fo2 + 2Fc2)/3
3871 reflections(Δ/σ)max < 0.001
163 parametersΔρmax = 0.43 e Å3
0 restraintsΔρmin = 0.21 e Å3
Crystal data top
C27H18F4N2O2V = 2128.57 (8) Å3
Mr = 478.43Z = 4
Monoclinic, C2/cMo Kα radiation
a = 42.0478 (10) ŵ = 0.12 mm1
b = 5.2980 (1) ÅT = 100 K
c = 9.5643 (2) Å0.48 × 0.38 × 0.05 mm
β = 92.522 (2)°
Data collection top
Bruker APEXII DUO CCD
diffractometer
3871 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
3172 reflections with I > 2σ(I)
Tmin = 0.946, Tmax = 0.994Rint = 0.031
26445 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0400 restraints
wR(F2) = 0.114H atoms treated by a mixture of independent and constrained refinement
S = 1.06Δρmax = 0.43 e Å3
3871 reflectionsΔρmin = 0.21 e Å3
163 parameters
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
F10.131371 (14)0.52803 (12)0.04350 (6)0.02016 (14)
F20.201443 (15)1.06377 (13)0.30050 (7)0.02303 (15)
O10.136883 (18)0.97437 (15)0.36217 (7)0.02009 (16)
N10.113987 (19)1.00956 (16)0.14156 (8)0.01541 (16)
C10.16118 (2)0.60034 (18)0.08307 (9)0.01554 (17)
C20.18629 (3)0.4631 (2)0.03344 (10)0.01989 (19)
H2A0.18260.32190.02640.024*
C30.21695 (2)0.5379 (2)0.07365 (11)0.0223 (2)
H3A0.23460.44820.03980.027*
C40.22225 (2)0.7422 (2)0.16280 (11)0.0207 (2)
H4A0.24330.79410.18950.025*
C50.19617 (2)0.86802 (19)0.21155 (10)0.01656 (18)
C60.16482 (2)0.80494 (17)0.17353 (9)0.01396 (16)
C70.13715 (2)0.93935 (17)0.23513 (9)0.01430 (17)
C80.08569 (2)1.13880 (18)0.17534 (9)0.01475 (17)
C90.08638 (2)1.33660 (19)0.27115 (10)0.01791 (18)
H9A0.10581.38260.31890.021*
C100.05852 (2)1.46660 (19)0.29678 (10)0.01816 (18)
H10A0.05911.60040.36300.022*
C110.02971 (2)1.40427 (18)0.22709 (10)0.01674 (18)
C120.02942 (2)1.20383 (19)0.13243 (11)0.01962 (19)
H12A0.01001.15700.08520.024*
C130.05708 (2)1.07101 (19)0.10588 (10)0.01794 (18)
H13A0.05650.93520.04090.022*
C140.00001.5573 (3)0.25000.0213 (3)
H14A0.00401.66450.17020.026*
H1N10.1173 (3)0.984 (3)0.0566 (16)0.023 (4)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
F10.0186 (3)0.0209 (3)0.0208 (3)0.0022 (2)0.0022 (2)0.0022 (2)
F20.0207 (3)0.0257 (3)0.0225 (3)0.0035 (2)0.0013 (2)0.0072 (2)
O10.0220 (3)0.0272 (4)0.0112 (3)0.0051 (3)0.0022 (2)0.0005 (3)
N10.0144 (3)0.0210 (4)0.0110 (3)0.0032 (3)0.0022 (3)0.0003 (3)
C10.0159 (4)0.0180 (4)0.0127 (4)0.0003 (3)0.0000 (3)0.0020 (3)
C20.0249 (5)0.0197 (5)0.0151 (4)0.0056 (4)0.0019 (3)0.0017 (3)
C30.0201 (4)0.0269 (5)0.0202 (4)0.0078 (4)0.0043 (4)0.0006 (4)
C40.0148 (4)0.0268 (5)0.0205 (4)0.0026 (3)0.0012 (3)0.0017 (4)
C50.0168 (4)0.0189 (4)0.0139 (4)0.0001 (3)0.0001 (3)0.0001 (3)
C60.0146 (4)0.0161 (4)0.0112 (3)0.0008 (3)0.0011 (3)0.0009 (3)
C70.0150 (4)0.0151 (4)0.0130 (4)0.0003 (3)0.0022 (3)0.0010 (3)
C80.0137 (4)0.0176 (4)0.0132 (4)0.0012 (3)0.0024 (3)0.0011 (3)
C90.0151 (4)0.0220 (4)0.0166 (4)0.0002 (3)0.0003 (3)0.0031 (3)
C100.0166 (4)0.0194 (4)0.0186 (4)0.0005 (3)0.0023 (3)0.0036 (3)
C110.0139 (4)0.0158 (4)0.0208 (4)0.0000 (3)0.0042 (3)0.0014 (3)
C120.0145 (4)0.0198 (4)0.0244 (5)0.0008 (3)0.0001 (3)0.0023 (4)
C130.0166 (4)0.0185 (4)0.0187 (4)0.0000 (3)0.0004 (3)0.0032 (3)
C140.0140 (6)0.0159 (6)0.0343 (8)0.0000.0044 (5)0.000
Geometric parameters (Å, º) top
F1—C11.3489 (11)C6—C71.5058 (13)
F2—C51.3534 (11)C8—C91.3916 (13)
O1—C71.2297 (11)C8—C131.3954 (13)
N1—C71.3459 (12)C9—C101.3901 (13)
N1—C81.4222 (12)C9—H9A0.9500
N1—H1N10.842 (15)C10—C111.3963 (13)
C1—C21.3828 (13)C10—H10A0.9500
C1—C61.3911 (13)C11—C121.3952 (14)
C2—C31.3870 (15)C11—C141.5131 (12)
C2—H2A0.9500C12—C131.3922 (13)
C3—C41.3899 (15)C12—H12A0.9500
C3—H3A0.9500C13—H13A0.9500
C4—C51.3815 (13)C14—C11i1.5131 (12)
C4—H4A0.9500C14—H14A0.9601
C5—C61.3929 (12)
C7—N1—C8124.77 (8)N1—C7—C6114.80 (8)
C7—N1—H1N1116.8 (10)C9—C8—C13119.99 (9)
C8—N1—H1N1118.2 (10)C9—C8—N1121.25 (8)
F1—C1—C2117.93 (9)C13—C8—N1118.70 (8)
F1—C1—C6118.10 (8)C10—C9—C8119.73 (9)
C2—C1—C6123.96 (9)C10—C9—H9A120.1
C1—C2—C3117.96 (9)C8—C9—H9A120.1
C1—C2—H2A121.0C9—C10—C11121.26 (9)
C3—C2—H2A121.0C9—C10—H10A119.4
C2—C3—C4120.98 (9)C11—C10—H10A119.4
C2—C3—H3A119.5C12—C11—C10118.18 (9)
C4—C3—H3A119.5C12—C11—C14121.20 (8)
C5—C4—C3118.33 (9)C10—C11—C14120.57 (8)
C5—C4—H4A120.8C13—C12—C11121.31 (9)
C3—C4—H4A120.8C13—C12—H12A119.3
F2—C5—C4118.12 (8)C11—C12—H12A119.3
F2—C5—C6118.35 (8)C12—C13—C8119.51 (9)
C4—C5—C6123.53 (9)C12—C13—H13A120.2
C1—C6—C5115.22 (8)C8—C13—H13A120.2
C1—C6—C7123.11 (8)C11—C14—C11i115.22 (11)
C5—C6—C7121.53 (8)C11—C14—H14A108.5
O1—C7—N1125.27 (9)C11i—C14—H14A108.4
O1—C7—C6119.92 (8)
F1—C1—C2—C3179.76 (9)C5—C6—C7—O146.84 (13)
C6—C1—C2—C31.62 (15)C1—C6—C7—N150.49 (12)
C1—C2—C3—C40.95 (16)C5—C6—C7—N1133.95 (9)
C2—C3—C4—C50.57 (16)C7—N1—C8—C942.34 (14)
C3—C4—C5—F2178.73 (9)C7—N1—C8—C13140.39 (10)
C3—C4—C5—C61.60 (15)C13—C8—C9—C100.27 (15)
F1—C1—C6—C5179.29 (8)N1—C8—C9—C10176.96 (9)
C2—C1—C6—C50.68 (14)C8—C9—C10—C110.61 (15)
F1—C1—C6—C73.47 (13)C9—C10—C11—C121.22 (15)
C2—C1—C6—C7175.14 (9)C9—C10—C11—C14176.46 (9)
F2—C5—C6—C1179.35 (8)C10—C11—C12—C130.98 (15)
C4—C5—C6—C10.98 (14)C14—C11—C12—C13176.68 (9)
F2—C5—C6—C73.46 (13)C11—C12—C13—C80.14 (15)
C4—C5—C6—C7176.87 (9)C9—C8—C13—C120.50 (15)
C8—N1—C7—O10.91 (16)N1—C8—C13—C12176.80 (9)
C8—N1—C7—C6179.94 (8)C12—C11—C14—C11i47.96 (8)
C1—C6—C7—O1128.72 (10)C10—C11—C14—C11i134.43 (10)
Symmetry code: (i) x, y, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N1···O1ii0.841 (15)2.078 (15)2.8811 (11)159.4 (14)
C9—H9A···F1iii0.952.413.2318 (11)145
Symmetry codes: (ii) x, y+2, z1/2; (iii) x, y+2, z+1/2.

Experimental details

Crystal data
Chemical formulaC27H18F4N2O2
Mr478.43
Crystal system, space groupMonoclinic, C2/c
Temperature (K)100
a, b, c (Å)42.0478 (10), 5.2980 (1), 9.5643 (2)
β (°) 92.522 (2)
V3)2128.57 (8)
Z4
Radiation typeMo Kα
µ (mm1)0.12
Crystal size (mm)0.48 × 0.38 × 0.05
Data collection
DiffractometerBruker APEXII DUO CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.946, 0.994
No. of measured, independent and
observed [I > 2σ(I)] reflections
26445, 3871, 3172
Rint0.031
(sin θ/λ)max1)0.759
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.114, 1.06
No. of reflections3871
No. of parameters163
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.43, 0.21

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

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N1···O1i0.841 (15)2.078 (15)2.8811 (11)159.4 (14)
C9—H9A···F1ii0.952.413.2318 (11)145
Symmetry codes: (i) x, y+2, z1/2; (ii) x, y+2, z+1/2.
 

Footnotes

Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

NM gratefully acknowledges funding from Universiti Sains Malaysia under the University Research Grant (No. 1001/PFARMASI/821142). HKF and MH thank the Malaysian Government and Universiti Sains Malaysia for the Research University Grant No. 1001/PFIZIK/811160. MH also thanks Universiti Sains Malaysia for a post-doctoral research fellowship.

References

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