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Acta Cryst. (2009). E65, o1471    [ doi:10.1107/S1600536809020261 ]

2-(4-tert-Butylphenyl)-1H-imidazo[4,5-f][1,10]phenanthroline sesquihydrate

C.-Y. Zheng and T.-Q. Sun

Abstract top

In the title compound, C23H20N4·1.5H2O, the mean planes of the imidazo[4,5-f][1,10]phenanthroline system and the benzene ring make a dihedral angle of 21.76 (2)°. One water O atom lies on a twofold rotation axis. The organic molecules and water molecules are linked via N-H...O, O-H...N and O-H...O hydrogen bonds. Weak intermolecular C-H...N hydrogen bonds and [pi]-[pi] stacking interactions between inversion-related phenanthroline rings complete the three-dimensional hydrogen-bonding network in the crystal structure. The stacking distance is short at 3.513 (2) Å and the perpendicular distance between the rings is 3.355 Å. The three methyl groups are disordered over two positions, with a site-occupancy ratio of 0.875 (14):0.125 (14).

Comment top

1,10-Phenanthroline and its derivatives are commonly used as ligands in metal complexes (Bian et al. 2002; Cardinaels et al. 2005; Liu et al. 2005; Wu et al. 1998). We report here the structure of the title compound (I) (Fig. 1), which was synthesized from [4,5-f]1,10-phenanthroline. The mean plane of the [4,5-f]1,10-phenanthroline moiety and the benzene ring (C14 - C19) make a dihedral angle of 21.76 (2) °. The water oxygen atom O2 occupies a twofold rotation axis, generating a symmetric four-centre hydrogen bond system that link two imidazo groups and two water molecules O1 via O—H···N and O—H···O bonds (Fig. 2). The other water molecules O1 link the two phenanthroline N-atoms through bifurcated O—H···N hydrogen bonds (Table 1). Intermolecular C—H···N hydrogen bonds and π—π stacking interactions (Janiak, 2000) between inversion related phenanthroline rings complete the hydrogen bonding network in the crystal structure. The short stacking distance Cgi—Cgj is 3.513 (2) Å, the perpendicular distance between the rings is 3.355 Å, and the dihedral angle between the rings is 2.48 °. Cg is the centroid of ring (N2, C5, C4, C12, C11, C10), a symmetry code for Cgj was given as (1 - y, 1 - x, 5/2 - z. The three methyl groups are disordered over two positions, with a site occupancy ratio of ca 7:1.

Related literature top

For 1,10-phenanthroline derivatives as ligands, see: Cardinaels et al. (2005); Liu et al. (2005). For the crystal structures of 1,10-phenanthroline derivatives, see: Bian et al. (2002); Wu et al. (1998). For aromatic π—π stacking interactions, see: Janiak (2000).

Experimental top

1,10-Phenanthroline-5,6-dione (0.84 g, 0.004 mol) and ammonium acetate (3.1 g, 0.04 mmol) were dissolved in 40 ml of hot glacial acetic acid. While the mixture was stirred, a solution of 4-tert-butylbenzaldehyde (0.65 g, 0.004 mmol) in 10 ml of glacial acetic acid was added dropwise to the mixture. The mixture was heated at 363 K for 3 h and was then poured in 200 ml of water. The solution was neutralized with ammonia to pH=8 and was then cooled to room temperature. The precipitate was filtered off and recrystallized from dillute ethanol solution to give the title compound (I). Crystals suitable for X-ray diffraction were grown by slow evaporation of the EtOH solutions at room temperature.

Refinement top

The methyl groups were found to be disordered over two orientations. The occupancies of the disordered positions C21/C21', C22/C22' and C23/C23' were refined to 0.875 (14)/0.125 (14). Suitable restraints were applied to the C—C distances involving the disordered atoms. The methyl H atoms were constrained to an ideal geometry with C—H distances of 0.96 Å and Uiso(H) = 1.5 Ueq(C), but each group was allowed to rotate freely about its C—C bond. Other H atoms were placed in geometrically idealized positions and constrained to ride on their parent C atoms, with C—H distances of 0.93 to 0.97 Å, and with Uiso(H) = 1.2 Ueq(C). All H atoms on N atoms were positioned geometrically and refined as riding atoms, with N—H = 0.86 Å and Uiso(H) = 1.2 Ueq(N). The H atoms of the waters were located in a Fourier map following isotropic refinement. In the absence of significant anomalous scattering effects, Friedel related intensity reflections were averaged.

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (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. View of the molecular structure of (I), showing the atomic numbering. Displacement ellipsoids are drawn at the 50% probability level. Hydrogen bonds are indicated by dashed lines. The three disordered methyl groups were omitted for clarity.
[Figure 2] Fig. 2. A section of the structure of (I) with intermolecular hydrogen bonds indicated as dashed lines.
2-(4-tert-Butylphenyl)-1H-imidazo[4,5-f][1,10] phenanthroline sesquihydrate top
Crystal data top
C23H20N4·1.5H2ODx = 1.257 Mg m−3
Mr = 379.46Mo Kα radiation, λ = 0.71073 Å
Tetragonal, P43212Cell parameters from 5405 reflections
Hall symbol: P4nw 2abwθ = 2.2–22.5°
a = 14.809 (4) ŵ = 0.08 mm−1
c = 18.281 (6) ÅT = 298 K
V = 4009.1 (19) Å3Block, yellow
Z = 80.16 × 0.13 × 0.10 mm
F(000) = 1608
Data collection top
Bruker SMART CCD area-detector
diffractometer		2508 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.054
graphiteθmax = 27.5°, θmin = 1.9°
φ and ω scansh = −19→19
46858 measured reflectionsk = −19→19
2670 independent reflectionsl = −23→23
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)] = 0.068Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.167H atoms treated by a mixture of independent and constrained refinement
S = 1.28 w = 1/[σ2(Fo2) + (0.0765P)2 + 0.9688P]
where P = (Fo2 + 2Fc2)/3
2670 reflections(Δ/σ)max < 0.001
304 parametersΔρmax = 0.30 e Å−3
53 restraintsΔρmin = −0.15 e Å−3
Crystal data top
C23H20N4·1.5H2OZ = 8
Mr = 379.46Mo Kα radiation
Tetragonal, P43212µ = 0.08 mm−1
a = 14.809 (4) ÅT = 298 K
c = 18.281 (6) Å0.16 × 0.13 × 0.10 mm
V = 4009.1 (19) Å3
Data collection top
Bruker SMART CCD area-detector
diffractometer		2508 reflections with I > 2σ(I)
46858 measured reflectionsRint = 0.054
2670 independent reflectionsθmax = 27.5°
Refinement top
R[F2 > 2σ(F2)] = 0.068H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.167Δρmax = 0.30 e Å−3
S = 1.28Δρmin = −0.15 e Å−3
2670 reflectionsAbsolute structure: ?
304 parametersFlack parameter: ?
53 restraintsRogers parameter: ?
Special details top

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) top
xyzUiso*/UeqOcc. (<1)
C10.7310 (2)0.4019 (2)1.19064 (17)0.0436 (7)
C20.6832 (2)0.3733 (2)1.12626 (16)0.0412 (7)
C30.6074 (2)0.4156 (2)1.10102 (16)0.0392 (7)
C40.5709 (2)0.4934 (2)1.13671 (16)0.0399 (7)
C50.6151 (2)0.5242 (2)1.20079 (17)0.0424 (7)
C60.6959 (2)0.4778 (2)1.22760 (17)0.0453 (8)
N10.7345 (2)0.5111 (2)1.28912 (17)0.0593 (9)
C70.8061 (3)0.4692 (3)1.3142 (2)0.0723 (13)
H70.83250.49151.35670.087*
C80.8453 (3)0.3944 (4)1.2822 (3)0.0760 (14)
H80.89610.36761.30270.091*
C90.8074 (3)0.3605 (3)1.2194 (2)0.0623 (10)
H90.83250.31041.19650.075*
N20.5840 (2)0.5952 (2)1.23928 (16)0.0505 (7)
C100.5114 (3)0.6373 (3)1.2156 (2)0.0538 (9)
H100.49010.68601.24280.065*
C110.4647 (3)0.6138 (3)1.1531 (2)0.0569 (9)
H110.41390.64601.13850.068*
C120.4950 (2)0.5420 (2)1.11298 (19)0.0504 (8)
H120.46540.52541.07020.060*
C130.6348 (2)0.3069 (2)1.02710 (16)0.0416 (7)
C140.6341 (2)0.2461 (2)0.96339 (16)0.0426 (7)
C150.5563 (2)0.2359 (2)0.92178 (18)0.0480 (8)
H150.50380.26570.93590.058*
C160.5553 (3)0.1825 (2)0.85987 (18)0.0500 (8)
H160.50200.17640.83350.060*
C170.6319 (3)0.1377 (2)0.83626 (18)0.0510 (9)
C180.7096 (3)0.1491 (3)0.8774 (2)0.0616 (11)
H180.76230.12020.86270.074*
C190.7112 (3)0.2021 (3)0.93992 (19)0.0566 (10)
H190.76460.20820.96630.068*
C200.6326 (3)0.0806 (3)0.76548 (19)0.0646 (11)
C210.5375 (4)0.0646 (6)0.7367 (4)0.110 (3)0.875 (14)
H21A0.54040.02910.69280.165*0.875 (14)
H21B0.50940.12160.72620.165*0.875 (14)
H21C0.50280.03310.77290.165*0.875 (14)
C220.6769 (8)−0.0099 (5)0.7785 (4)0.122 (4)0.875 (14)
H22A0.6722−0.04600.73510.183*0.875 (14)
H22B0.6472−0.04010.81820.183*0.875 (14)
H22C0.7394−0.00100.79040.183*0.875 (14)
C230.6840 (7)0.1327 (6)0.7075 (3)0.125 (4)0.875 (14)
H23A0.74100.15190.72690.188*0.875 (14)
H23B0.64950.18460.69290.188*0.875 (14)
H23C0.69400.09450.66580.188*0.875 (14)
C21'0.565 (3)0.003 (3)0.765 (3)0.13 (2)0.125 (14)
H21D0.5711−0.03030.71990.188*0.125 (14)
H21E0.50470.02680.76800.188*0.125 (14)
H21F0.5762−0.03620.80540.188*0.125 (14)
C22'0.7261 (17)0.040 (4)0.752 (3)0.099 (17)0.125 (14)
H22D0.7216−0.00800.71690.149*0.125 (14)
H22E0.74900.01540.79760.149*0.125 (14)
H22F0.76640.08530.73470.149*0.125 (14)
C23'0.612 (4)0.140 (3)0.6995 (18)0.12 (2)0.125 (14)
H23D0.63900.11460.65650.174*0.125 (14)
H23E0.63650.19960.70760.174*0.125 (14)
H23F0.54790.14460.69290.174*0.125 (14)
N30.70020 (19)0.30431 (19)1.07917 (14)0.0433 (6)
H30.734 (2)0.2580 (17)1.086 (2)0.052*
N40.57632 (19)0.37297 (18)1.03858 (13)0.0417 (6)
O10.8076 (2)0.1575 (2)1.11023 (13)0.0661 (9)
H1A0.852 (2)0.159 (4)1.0831 (19)0.099*
H1B0.824 (3)0.140 (4)1.1511 (13)0.099*
O20.38586 (17)0.38586 (17)1.00000.0487 (8)
H2A0.4347 (17)0.366 (3)1.014 (3)0.073*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0486 (18)0.0470 (18)0.0354 (14)−0.0038 (15)−0.0049 (13)0.0075 (13)
C20.0490 (18)0.0405 (16)0.0341 (14)−0.0017 (14)−0.0012 (13)0.0037 (12)
C30.0475 (17)0.0393 (15)0.0307 (13)−0.0020 (13)−0.0058 (12)0.0041 (12)
C40.0453 (17)0.0405 (16)0.0340 (14)−0.0022 (13)−0.0008 (13)0.0001 (12)
C50.0510 (18)0.0420 (17)0.0342 (14)−0.0069 (14)0.0002 (13)0.0027 (12)
C60.0514 (18)0.0490 (18)0.0355 (15)−0.0111 (15)−0.0054 (14)0.0018 (13)
N10.064 (2)0.069 (2)0.0451 (15)−0.0063 (17)−0.0158 (15)−0.0029 (15)
C70.079 (3)0.081 (3)0.057 (2)−0.006 (3)−0.031 (2)−0.004 (2)
C80.069 (3)0.086 (3)0.072 (3)0.010 (3)−0.031 (2)0.002 (3)
C90.062 (2)0.064 (2)0.061 (2)0.005 (2)−0.0200 (19)−0.0030 (19)
N20.0604 (18)0.0486 (16)0.0425 (14)−0.0071 (13)−0.0021 (14)−0.0057 (13)
C100.061 (2)0.0452 (18)0.0552 (19)−0.0009 (16)0.0023 (18)−0.0122 (17)
C110.060 (2)0.048 (2)0.062 (2)0.0087 (17)−0.0095 (18)−0.0069 (17)
C120.058 (2)0.0471 (18)0.0459 (17)0.0003 (16)−0.0133 (16)−0.0037 (15)
C130.0492 (17)0.0409 (16)0.0347 (14)0.0019 (14)−0.0003 (13)0.0050 (13)
C140.0523 (18)0.0408 (16)0.0349 (14)0.0042 (14)−0.0006 (14)0.0033 (13)
C150.0472 (19)0.0515 (19)0.0452 (16)0.0083 (15)0.0009 (15)−0.0064 (15)
C160.058 (2)0.051 (2)0.0408 (16)0.0000 (17)−0.0041 (16)−0.0042 (15)
C170.073 (2)0.0489 (19)0.0317 (14)0.0097 (17)0.0009 (16)−0.0007 (14)
C180.066 (2)0.074 (3)0.0446 (18)0.029 (2)−0.0004 (18)−0.0092 (18)
C190.056 (2)0.069 (2)0.0449 (18)0.0161 (19)−0.0064 (16)−0.0076 (17)
C200.090 (3)0.069 (3)0.0340 (17)0.016 (2)−0.0018 (19)−0.0102 (18)
C210.111 (5)0.131 (7)0.088 (5)−0.003 (5)−0.016 (4)−0.068 (5)
C220.194 (10)0.100 (6)0.072 (4)0.064 (6)−0.030 (5)−0.038 (4)
C230.169 (9)0.162 (8)0.044 (3)−0.053 (7)0.024 (4)−0.020 (4)
C21'0.13 (3)0.12 (3)0.13 (3)−0.006 (19)−0.007 (19)−0.019 (19)
C22'0.11 (2)0.10 (2)0.09 (2)0.019 (17)−0.012 (17)−0.026 (18)
C23'0.13 (3)0.11 (3)0.11 (2)0.003 (19)−0.011 (19)−0.014 (18)
N30.0484 (16)0.0451 (15)0.0363 (13)0.0073 (12)−0.0044 (12)0.0032 (12)
N40.0514 (15)0.0418 (14)0.0319 (11)0.0064 (12)−0.0039 (12)−0.0008 (11)
O10.0715 (19)0.086 (2)0.0412 (12)0.0343 (17)0.0099 (13)0.0085 (14)
O20.0519 (12)0.0519 (12)0.0422 (17)−0.0066 (17)0.0024 (11)−0.0024 (11)
Geometric parameters (Å, °) top
C1—C91.390 (5)C17—C181.384 (6)
C1—C61.411 (5)C17—C201.545 (5)
C1—C21.437 (4)C18—C191.387 (5)
C2—N31.360 (4)C18—H180.9300
C2—C31.366 (4)C19—H190.9300
C3—N41.383 (4)C20—C221.511 (6)
C3—C41.431 (5)C20—C231.516 (6)
C4—C121.403 (5)C20—C211.522 (6)
C4—C51.418 (4)C20—C21'1.524 (10)
C5—N21.346 (4)C20—C23'1.527 (10)
C5—C61.465 (5)C20—C22'1.532 (10)
C6—N11.354 (4)C21—H21A0.9600
N1—C71.312 (6)C21—H21B0.9600
C7—C81.381 (7)C21—H21C0.9600
C7—H70.9300C22—H22A0.9600
C8—C91.372 (6)C22—H22B0.9600
C8—H80.9300C22—H22C0.9600
C9—H90.9300C23—H23A0.9600
N2—C101.316 (5)C23—H23B0.9600
C10—C111.382 (5)C23—H23C0.9600
C10—H100.9300C21'—H21D0.9600
C11—C121.367 (5)C21'—H21E0.9600
C11—H110.9300C21'—H21F0.9600
C12—H120.9300C22'—H22D0.9600
C13—N41.323 (4)C22'—H22E0.9600
C13—N31.359 (4)C22'—H22F0.9600
C13—C141.472 (4)C23'—H23D0.9600
C14—C191.383 (5)C23'—H23E0.9600
C14—C151.389 (5)C23'—H23F0.9600
C15—C161.381 (5)N3—H30.86 (3)
C15—H150.9300O1—H1A0.83 (3)
C16—C171.383 (5)O1—H1B0.83 (3)
C16—H160.9300O2—H2A0.82 (3)
C9—C1—C6118.0 (3)C19—C18—H18119.0
C9—C1—C2125.5 (3)C14—C19—C18120.5 (4)
C6—C1—C2116.4 (3)C14—C19—H19119.7
N3—C2—C3106.4 (3)C18—C19—H19119.7
N3—C2—C1130.4 (3)C22—C20—C23110.0 (5)
C3—C2—C1123.2 (3)C22—C20—C21108.5 (5)
C2—C3—N4110.1 (3)C23—C20—C21107.6 (5)
C2—C3—C4121.7 (3)C23—C20—C21'135 (2)
N4—C3—C4128.2 (3)C22—C20—C23'136.5 (19)
C12—C4—C5117.4 (3)C21'—C20—C23'107.3 (10)
C12—C4—C3125.1 (3)C21—C20—C22'136.1 (18)
C5—C4—C3117.5 (3)C21'—C20—C22'107.1 (9)
N2—C5—C4121.7 (3)C23'—C20—C22'106.7 (9)
N2—C5—C6118.1 (3)C22—C20—C17110.9 (3)
C4—C5—C6120.2 (3)C23—C20—C17108.1 (4)
N1—C6—C1122.2 (3)C21—C20—C17111.7 (4)
N1—C6—C5116.9 (3)C21'—C20—C17115 (2)
C1—C6—C5121.0 (3)C23'—C20—C17110.1 (19)
C7—N1—C6117.4 (4)C22'—C20—C17110.7 (17)
N1—C7—C8124.8 (4)C20—C21—H21A109.5
N1—C7—H7117.6C20—C21—H21B109.5
C8—C7—H7117.6C20—C21—H21C109.5
C9—C8—C7118.5 (4)C20—C22—H22A109.5
C9—C8—H8120.8C20—C22—H22B109.5
C7—C8—H8120.8C20—C22—H22C109.5
C8—C9—C1119.2 (4)C20—C23—H23A109.5
C8—C9—H9120.4C20—C23—H23B109.5
C1—C9—H9120.4C20—C23—H23C109.5
C10—N2—C5118.5 (3)C20—C21'—H21D109.5
N2—C10—C11124.2 (3)C20—C21'—H21E109.5
N2—C10—H10117.9H21D—C21'—H21E109.5
C11—C10—H10117.9C20—C21'—H21F109.5
C12—C11—C10118.4 (4)H21D—C21'—H21F109.5
C12—C11—H11120.8H21E—C21'—H21F109.5
C10—C11—H11120.8C20—C22'—H22D109.5
C11—C12—C4119.7 (3)C20—C22'—H22E109.5
C11—C12—H12120.1H22D—C22'—H22E109.5
C4—C12—H12120.1C20—C22'—H22F109.5
N4—C13—N3112.1 (3)H22D—C22'—H22F109.5
N4—C13—C14125.0 (3)H22E—C22'—H22F109.5
N3—C13—C14122.8 (3)C20—C23'—H23D109.5
C19—C14—C15117.7 (3)C20—C23'—H23E109.5
C19—C14—C13121.8 (3)H23D—C23'—H23E109.5
C15—C14—C13120.4 (3)C20—C23'—H23F109.5
C16—C15—C14121.3 (3)H23D—C23'—H23F109.5
C16—C15—H15119.4H23E—C23'—H23F109.5
C14—C15—H15119.4C13—N3—C2106.9 (3)
C15—C16—C17121.5 (3)C13—N3—H3123 (3)
C15—C16—H16119.3C2—N3—H3128 (3)
C17—C16—H16119.3C13—N4—C3104.5 (3)
C16—C17—C18117.0 (3)C13—N4—H2A124.9 (13)
C16—C17—C20121.9 (4)C3—N4—H2A121.2 (13)
C18—C17—C20121.1 (3)H3—O1—H1A107 (4)
C17—C18—C19122.1 (4)H3—O1—H1B128 (4)
C17—C18—H18119.0H1A—O1—H1B109 (4)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O1—H1A···N1i0.83 (3)2.45 (3)3.193 (5)151 (5)
O1—H1A···N2i0.83 (3)2.19 (4)2.853 (4)137 (5)
O1—H1B···O2ii0.83 (3)2.07 (2)2.878 (3)168 (5)
O2—H2A···N40.82 (3)2.15 (2)2.914 (4)156 (5)
N3—H3···O10.86 (3)1.90 (3)2.754 (4)176 (4)
C12—H12···N4iii0.932.533.346 (4)147
Symmetry codes: (i) −y+3/2, x−1/2, z−1/4; (ii) y+1/2, −x+1/2, z+1/4; (iii) y, x, −z+2.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O1—H1A···N1i0.83 (3)2.45 (3)3.193 (5)151 (5)
O1—H1A···N2i0.83 (3)2.19 (4)2.853 (4)137 (5)
O1—H1B···O2ii0.83 (3)2.07 (2)2.878 (3)168 (5)
O2—H2A···N40.82 (3)2.15 (2)2.914 (4)156 (5)
N3—H3···O10.86 (3)1.90 (3)2.754 (4)176 (4)
C12—H12···N4iii0.932.533.346 (4)147
Symmetry codes: (i) −y+3/2, x−1/2, z−1/4; (ii) y+1/2, −x+1/2, z+1/4; (iii) y, x, −z+2.
Acknowledgements top

The authors are grateful to the Postgraduate Programme of Hubei Normal University for financial support under grant No. 2008D53.

references
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