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Acta Crystallogr Sect E Struct Rep Online. 2008 November 1; 64(Pt 11): o2221.
Published online 2008 October 31. doi:  10.1107/S160053680803448X
PMCID: PMC2959675

tert-Butyl N-benzyl-N-[4-(4-fluoro­benzoyl­meth­yl)-2-pyrid­yl]carbamate

Abstract

In the crystal structure of the title compound, C25H25FN2O3, the pyridine ring makes dihedral angles of 75.1 (3), 39.4 (3) and 74.6 (3)° with the phenyl ring, the carbamate plane and the 4-fluoro­phenyl ring, respectively. The phenyl ring makes dihedral angles of 77.2 (3) and 23.6 (3)° with the carbamate plane and the 4-fluoro­phenyl ring, respectively. The 4-fluoro­phenyl ring is perpendicular to the carbamate plane, the dihedral angle between them being 89.5 (3)°.

Related literature

For preparation of the title compound, see: Koch et al. (2008a [triangle]). For applications of the vicinal 4-fluoro­phen­yl/pyridin-4-yl pharmacophore in p38 MAP kinase inhibitors, see, for example: Koch et al. (2008a [triangle]); for thia­zolopyridines, see: Miwatashi et al. (2005 [triangle]); for pyrazolopyridines, see: Stevens et al. (2005 [triangle]). For a related structure, see: Koch, et al. (2008b [triangle]).

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Object name is e-64-o2221-scheme1.jpg

Experimental

Crystal data

  • C25H25FN2O3
  • M r = 420.47
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-64-o2221-efi1.jpg
  • a = 38.054 (7) Å
  • b = 7.9320 (6) Å
  • c = 14.589 (3) Å
  • β = 102.142 (8)°
  • V = 4305.1 (11) Å3
  • Z = 8
  • Cu Kα radiation
  • μ = 0.75 mm−1
  • T = 193 (2) K
  • 0.35 × 0.30 × 0.18 mm

Data collection

  • Enraf–Nonius CAD-4 diffractometer
  • Absorption correction: none
  • 4272 measured reflections
  • 4091 independent reflections
  • 2192 reflections with I > 2σ(I)
  • R int = 0.076
  • 3 standard reflections frequency: 60 min intensity decay: 3%

Refinement

  • R[F 2 > 2σ(F 2)] = 0.110
  • wR(F 2) = 0.339
  • S = 1.10
  • 4091 reflections
  • 283 parameters
  • H-atom parameters constrained
  • Δρmax = 0.48 e Å−3
  • Δρmin = −0.64 e Å−3

Data collection: CAD-4 Software (Enraf–Nonius, 1989 [triangle]); cell refinement: CAD-4 Software; data reduction: CORINC (Dräger & Gattow, 1971 [triangle]); program(s) used to solve structure: SIR97 (Altomare et al., 1999 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: PLATON (Spek, 2003 [triangle]); software used to prepare material for publication: PLATON.

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053680803448X/si2118sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S160053680803448X/si2118Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors thank the EU for financial support via the Framework Project 6 ‘MACROCEPT’, part of the EU–Craft Program.

supplementary crystallographic information

Comment

The title compound, (I), was obtained as an intermediate in the synthesis of 2-alkylsulfanyl-5-(2-aminopyridin-4-yl)-4-(4-fluorophenyl)imidazoles as potent p38 MAP kinase inhibitors (Koch et al. 2008a).

The vicinal 4-fluorophenyl/pyridin-4-yl system is a pharmacophore in different p38 MAP kinase inhibitors, like the imidazolopyridines (Koch et al. 2008a,b) and related pyridine compounds (Miwatashi et al. 2005), (Stevens et al. 2005).

In the crystal structure of the title compound I, Fig. 1, the pyridine ring makes dihedral angles of 75.1 (3)°, 39.4 (3)° and 74.6 (3)° to the phenyl ring (C1–C6), the carbamate plane and the 4-fluorophenyl ring (C18–C23), respectively. The phenyl ring (C1–C6) makes dihedral angles of 77.2 (3)° and 23.6 (3)° to the carbamate plane and the 4-fluorophenyl ring (C18–C23), respectively. The 4-fluorophenyl ring (C18–C23) is perpendicular to the carbamate acid plane, the dihedral angle between them is 89.5 (3)°.

The 4-fluorophenyl group is rotating away from the pyridine ring system compared to the recently published crystal structure of methyl 4-(5-(4-fluorophenyl)-4-(pyridin-4-yl)-1H-imidazol-2-ylthio)butanoate (Koch et al. 2008b).

Experimental

tert-Butyl N-benzyl-N-(4-methylpyridin-2-yl)carbamate (6.27 g, 21.0 mmol) and ethyl 4-fluorobenzoate (3.89 g, 23.1 mmol) were dissolved in dry THF (60 ml) under argon atmosphere. The solution was cooled to 273 K and NaHMDS (21.0 ml, 42.0 mmol, 2 M in THF) was added dropwise. The mixture was allowed to stir at this temperature for 1 h and additional 2.5 h at room temperature. The reaction was quenched with saturated NH4Cl solution, EtOAc was added and the mixture was extracted twice with water. The organic layer was dried (sodium sulfate) and concentrated in vacuo. The crude product was purified by flash chromatography (silica gel, petroleum ether/ethylacetate 5–1 to 3–1) to yield 5.40 g (61%) of I as colourless crystals (Koch et al. 2008a).

Refinement

Hydrogen atoms attached to carbons were placed at calculated positions with C—H = 0.95 Å (aromatic) or 0.98–0.99 Å (sp3 C-atom). All H atoms were refined in the riding-model approximation with isotropic displacement parameters (set at 1.2–1.5 times of the Ueq of the parent atom).

Figures

Fig. 1.
View of compound I. Displacement ellipsoids are drawn at the 50% probability level. H atoms are depicted as circles of arbitrary size.

Crystal data

C25H25FN2O3F(000) = 1776
Mr = 420.47Dx = 1.297 Mg m3
Monoclinic, C2/cCu Kα radiation, λ = 1.54178 Å
Hall symbol: -C 2ycCell parameters from 25 reflections
a = 38.054 (7) Åθ = 15–28°
b = 7.9320 (6) ŵ = 0.75 mm1
c = 14.589 (3) ÅT = 193 K
β = 102.142 (8)°Plate, colourless
V = 4305.1 (11) Å30.35 × 0.30 × 0.18 mm
Z = 8

Data collection

Enraf–Nonius CAD-4 diffractometerRint = 0.076
Radiation source: rotating anodeθmax = 70.1°, θmin = 2.4°
graphiteh = −46→45
ω/2θ scansk = −9→0
4272 measured reflectionsl = 0→17
4091 independent reflections3 standard reflections every 60 min
2192 reflections with I > 2σ(I) intensity decay: 3%

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.110Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.339H-atom parameters constrained
S = 1.10w = 1/[σ2(Fo2) + (0.182P)2] where P = (Fo2 + 2Fc2)/3
4091 reflections(Δ/σ)max < 0.001
283 parametersΔρmax = 0.48 e Å3
0 restraintsΔρmin = −0.64 e Å3

Special details

Experimental. No absorption correction was applied because of irregular crystal shape and low crystal quality. The crystal diffracted only very weak (less the 55% observed reflections).
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. 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)

xyzUiso*/Ueq
C10.30976 (15)0.4803 (7)0.3672 (4)0.0242 (12)
C20.33725 (17)0.5800 (8)0.4143 (4)0.0324 (14)
H20.36120.53830.42690.039*
C30.33038 (19)0.7421 (8)0.4438 (5)0.0406 (16)
H30.34950.80940.47730.049*
C40.2957 (2)0.8035 (9)0.4240 (5)0.0422 (17)
H40.29090.91370.44370.051*
C50.26812 (18)0.7057 (9)0.3759 (4)0.0386 (16)
H50.24430.74860.36190.046*
C60.27507 (16)0.5439 (8)0.3476 (4)0.0297 (13)
H60.25590.47640.31460.036*
C70.31548 (15)0.3018 (8)0.3346 (4)0.0265 (13)
H7A0.29450.23250.34060.032*
H7B0.31630.30580.26720.032*
N80.34806 (12)0.2177 (6)0.3852 (3)0.0273 (11)
C90.37651 (15)0.1822 (7)0.3379 (4)0.0241 (12)
N100.38074 (14)0.3047 (6)0.2779 (3)0.0326 (12)
C110.40604 (19)0.2738 (9)0.2270 (5)0.0440 (18)
H110.40970.35820.18380.053*
C120.42649 (17)0.1328 (9)0.2326 (4)0.0389 (16)
H120.44330.11780.19340.047*
C130.42200 (15)0.0098 (8)0.2982 (4)0.0268 (13)
C140.39684 (15)0.0377 (7)0.3519 (4)0.0240 (12)
H140.3936−0.04180.39810.029*
C150.44316 (16)−0.1512 (8)0.3080 (4)0.0297 (13)
H15A0.4419−0.19960.24480.036*
H15B0.4319−0.23280.34430.036*
C160.48232 (17)−0.1287 (8)0.3558 (5)0.0341 (15)
O170.49559 (13)0.0077 (6)0.3700 (5)0.0666 (18)
C180.50420 (15)−0.2837 (8)0.3851 (4)0.0268 (13)
C190.49111 (16)−0.4454 (8)0.3620 (4)0.0279 (13)
H190.4676−0.45970.32490.034*
C200.51188 (18)−0.5852 (8)0.3923 (4)0.0337 (15)
H200.5030−0.69570.37660.040*
C210.54570 (18)−0.5608 (8)0.4458 (4)0.0332 (14)
C220.55982 (19)−0.4035 (9)0.4691 (5)0.0413 (17)
H220.5835−0.39070.50540.050*
C230.53868 (16)−0.2635 (8)0.4385 (4)0.0325 (14)
H230.5479−0.15350.45410.039*
F240.56589 (11)−0.6962 (5)0.4773 (3)0.0487 (11)
C250.35189 (15)0.1753 (7)0.4796 (3)0.0213 (12)
O260.37827 (11)0.1119 (5)0.5264 (3)0.0299 (10)
O270.32169 (10)0.2188 (5)0.5079 (2)0.0260 (9)
C280.32262 (16)0.2339 (8)0.6097 (3)0.0307 (14)
C290.32429 (19)0.0591 (10)0.6534 (4)0.0440 (18)
H29A0.3033−0.00630.62270.066*
H29B0.32450.06930.72040.066*
H29C0.34620.00180.64510.066*
C300.3536 (2)0.3456 (11)0.6559 (5)0.053 (2)
H30A0.37630.29530.64820.080*
H30B0.35370.35660.72280.080*
H30C0.35090.45730.62650.080*
C310.28696 (18)0.3212 (10)0.6091 (4)0.0443 (18)
H31A0.28610.42840.57520.066*
H31B0.28470.34280.67370.066*
H31C0.26720.24880.57790.066*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.032 (3)0.026 (3)0.018 (3)−0.006 (2)0.012 (2)0.000 (2)
C20.034 (3)0.027 (3)0.039 (3)−0.003 (3)0.014 (3)0.006 (3)
C30.052 (4)0.029 (4)0.042 (4)−0.015 (3)0.013 (3)−0.005 (3)
C40.061 (5)0.028 (4)0.042 (4)0.010 (3)0.021 (3)−0.005 (3)
C50.039 (4)0.045 (4)0.034 (3)0.010 (3)0.014 (3)0.005 (3)
C60.035 (3)0.033 (3)0.023 (3)0.004 (3)0.009 (2)0.002 (3)
C70.031 (3)0.036 (3)0.013 (2)0.002 (3)0.006 (2)−0.001 (2)
N80.029 (3)0.037 (3)0.018 (2)0.003 (2)0.0098 (19)0.002 (2)
C90.027 (3)0.027 (3)0.019 (2)−0.002 (2)0.006 (2)0.002 (2)
N100.044 (3)0.029 (3)0.027 (3)0.007 (2)0.015 (2)0.009 (2)
C110.054 (4)0.046 (4)0.040 (4)0.013 (3)0.031 (3)0.021 (3)
C120.042 (4)0.049 (4)0.035 (3)0.012 (3)0.028 (3)0.011 (3)
C130.029 (3)0.029 (3)0.022 (3)−0.001 (3)0.005 (2)−0.003 (2)
C140.032 (3)0.025 (3)0.015 (2)−0.003 (2)0.006 (2)0.001 (2)
C150.037 (3)0.030 (3)0.026 (3)0.003 (3)0.015 (2)0.000 (3)
C160.036 (3)0.028 (3)0.040 (3)0.000 (3)0.011 (3)0.012 (3)
O170.042 (3)0.028 (3)0.118 (5)−0.006 (2)−0.011 (3)0.009 (3)
C180.027 (3)0.030 (3)0.027 (3)−0.001 (2)0.013 (2)0.003 (3)
C190.031 (3)0.032 (3)0.023 (3)0.000 (3)0.011 (2)−0.004 (3)
C200.051 (4)0.022 (3)0.033 (3)0.002 (3)0.020 (3)−0.001 (3)
C210.042 (4)0.035 (4)0.026 (3)0.014 (3)0.016 (3)0.004 (3)
C220.035 (4)0.050 (5)0.039 (4)0.006 (3)0.008 (3)0.009 (3)
C230.037 (3)0.030 (3)0.033 (3)−0.001 (3)0.013 (3)0.005 (3)
F240.062 (3)0.040 (2)0.045 (2)0.022 (2)0.015 (2)0.0098 (19)
C250.031 (3)0.021 (3)0.014 (2)−0.007 (2)0.008 (2)−0.004 (2)
O260.032 (2)0.040 (3)0.0165 (19)0.0031 (19)0.0030 (16)0.0027 (18)
O270.033 (2)0.032 (2)0.0157 (18)−0.0009 (18)0.0114 (16)−0.0026 (17)
C280.042 (3)0.043 (4)0.009 (2)−0.005 (3)0.011 (2)−0.007 (2)
C290.042 (4)0.070 (5)0.022 (3)−0.001 (4)0.010 (3)0.013 (3)
C300.055 (5)0.071 (6)0.035 (4)−0.017 (4)0.012 (3)−0.023 (4)
C310.053 (4)0.059 (5)0.025 (3)0.002 (4)0.019 (3)−0.003 (3)

Geometric parameters (Å, °)

C1—C21.374 (8)O27—C281.484 (6)
C1—C61.385 (8)C28—C301.515 (9)
C1—C71.525 (8)C28—C291.521 (9)
C2—C31.398 (9)C28—C311.522 (9)
C3—C41.378 (10)C2—H20.9500
C4—C51.375 (10)C3—H30.9500
C5—C61.391 (9)C4—H40.9500
C7—N81.464 (7)C5—H50.9500
N8—C251.396 (6)C6—H60.9500
N8—C91.429 (7)C7—H7A0.9900
C9—N101.340 (7)C7—H7B0.9900
C9—C141.374 (8)C11—H110.9500
N10—C111.356 (7)C12—H120.9500
C11—C121.355 (9)C14—H140.9500
C12—C131.403 (8)C15—H15A0.9900
C13—C141.376 (7)C15—H15B0.9900
C13—C151.500 (8)C19—H190.9500
C15—C161.517 (9)C20—H200.9500
C16—O171.194 (8)C22—H220.9500
C16—C181.496 (8)C23—H230.9500
C18—C231.387 (8)C29—H29A0.9800
C18—C191.391 (8)C29—H29B0.9800
C19—C201.380 (8)C29—H29C0.9800
C20—C211.371 (9)C30—H30A0.9800
C21—F241.344 (7)C30—H30B0.9800
C21—C221.373 (10)C30—H30C0.9800
C22—C231.389 (9)C31—H31A0.9800
C25—O261.199 (7)C31—H31B0.9800
C25—O271.345 (6)C31—H31C0.9800
C2—C1—C6119.1 (6)C4—C3—H3120.00
C2—C1—C7123.2 (5)C3—C4—H4120.00
C6—C1—C7117.8 (5)C5—C4—H4120.00
C1—C2—C3120.7 (6)C4—C5—H5120.00
C4—C3—C2119.6 (6)C6—C5—H5120.00
C5—C4—C3120.2 (6)C1—C6—H6120.00
C4—C5—C6120.0 (6)C5—C6—H6120.00
C1—C6—C5120.5 (6)N8—C7—H7A108.00
N8—C7—C1115.3 (5)N8—C7—H7B108.00
C25—N8—C9119.8 (5)C1—C7—H7A109.00
C25—N8—C7120.7 (4)C1—C7—H7B108.00
C9—N8—C7119.5 (4)H7A—C7—H7B107.00
N10—C9—C14124.1 (5)N10—C11—H11117.00
N10—C9—N8112.3 (5)C12—C11—H11117.00
C14—C9—N8123.5 (5)C11—C12—H12121.00
C9—N10—C11115.0 (5)C13—C12—H12121.00
C12—C11—N10125.5 (6)C9—C14—H14120.00
C11—C12—C13117.7 (5)C13—C14—H14120.00
C14—C13—C12118.4 (5)C13—C15—H15A109.00
C14—C13—C15120.5 (5)C13—C15—H15B109.00
C12—C13—C15121.1 (5)C16—C15—H15A109.00
C9—C14—C13119.1 (5)C16—C15—H15B109.00
C13—C15—C16113.6 (5)H15A—C15—H15B108.00
O17—C16—C18120.4 (6)C18—C19—H19120.00
O17—C16—C15121.7 (6)C20—C19—H19120.00
C18—C16—C15118.0 (5)C19—C20—H20121.00
C23—C18—C19119.4 (6)C21—C20—H20121.00
C23—C18—C16118.0 (6)C21—C22—H22121.00
C19—C18—C16122.6 (5)C23—C22—H22121.00
C20—C19—C18120.8 (6)C18—C23—H23120.00
C21—C20—C19118.4 (6)C22—C23—H23120.00
F24—C21—C20118.9 (6)C28—C29—H29A109.00
F24—C21—C22118.4 (6)C28—C29—H29B109.00
C20—C21—C22122.7 (6)C28—C29—H29C109.00
C21—C22—C23118.5 (6)H29A—C29—H29B110.00
C18—C23—C22120.3 (6)H29A—C29—H29C109.00
O26—C25—O27126.9 (5)H29B—C29—H29C109.00
O26—C25—N8124.3 (5)C28—C30—H30A109.00
O27—C25—N8108.8 (5)C28—C30—H30B110.00
C25—O27—C28119.0 (4)C28—C30—H30C109.00
O27—C28—C30110.2 (5)H30A—C30—H30B109.00
O27—C28—C29109.6 (5)H30A—C30—H30C109.00
C30—C28—C29112.8 (6)H30B—C30—H30C109.00
O27—C28—C31101.4 (5)C28—C31—H31A109.00
C30—C28—C31110.2 (6)C28—C31—H31B109.00
C29—C28—C31112.1 (5)C28—C31—H31C109.00
C1—C2—H2120.00H31A—C31—H31B109.00
C3—C2—H2120.00H31A—C31—H31C109.00
C2—C3—H3120.00H31B—C31—H31C110.00
C6—C1—C2—C31.3 (8)C12—C13—C15—C1673.5 (7)
C7—C1—C2—C3−179.1 (5)C13—C15—C16—O17−11.2 (9)
C1—C2—C3—C4−1.1 (9)C13—C15—C16—C18168.9 (5)
C2—C3—C4—C50.2 (10)O17—C16—C18—C237.5 (9)
C3—C4—C5—C60.5 (10)C15—C16—C18—C23−172.6 (5)
C2—C1—C6—C5−0.6 (8)O17—C16—C18—C19−173.4 (7)
C7—C1—C6—C5179.8 (5)C15—C16—C18—C196.5 (8)
C4—C5—C6—C1−0.3 (9)C23—C18—C19—C200.6 (8)
C2—C1—C7—N822.7 (7)C16—C18—C19—C20−178.4 (5)
C6—C1—C7—N8−157.7 (5)C18—C19—C20—C210.0 (8)
C1—C7—N8—C2566.5 (7)C19—C20—C21—F24178.7 (5)
C1—C7—N8—C9−112.1 (5)C19—C20—C21—C22−0.9 (9)
C25—N8—C9—N10−141.6 (5)F24—C21—C22—C23−178.5 (5)
C7—N8—C9—N1037.1 (7)C20—C21—C22—C231.1 (10)
C25—N8—C9—C1439.1 (8)C19—C18—C23—C22−0.5 (9)
C7—N8—C9—C14−142.3 (6)C16—C18—C23—C22178.6 (6)
C14—C9—N10—C112.8 (9)C21—C22—C23—C18−0.4 (9)
N8—C9—N10—C11−176.5 (6)C9—N8—C25—O261.4 (9)
C9—N10—C11—C120.0 (11)C7—N8—C25—O26−177.2 (6)
N10—C11—C12—C13−1.9 (12)C9—N8—C25—O27−179.2 (5)
C11—C12—C13—C141.0 (10)C7—N8—C25—O272.2 (7)
C11—C12—C13—C15179.1 (6)O26—C25—O27—C2817.1 (8)
N10—C9—C14—C13−3.7 (9)N8—C25—O27—C28−162.3 (5)
N8—C9—C14—C13175.5 (5)C25—O27—C28—C3051.0 (7)
C12—C13—C14—C91.6 (8)C25—O27—C28—C29−73.6 (6)
C15—C13—C14—C9−176.5 (5)C25—O27—C28—C31167.7 (5)
C14—C13—C15—C16−108.4 (6)

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: SI2118).

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