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ISSN: 2414-3146

1,1-Di­fluoro-3-phenyl-9-(pyridin-2-yl)-1H-1λ4,11λ4-1,3,5,2-oxadi­aza­borinino[3,4-a][1,8]naphthyridine

CROSSMARK_Color_square_no_text.svg

aCollege of Chemistry and Chemical Engineering, Yunnan Normal University, Kunming 650500, People's Republic of China
*Correspondence e-mail: chishaoming@gmail.com

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 21 June 2016; accepted 11 July 2016; online 22 July 2016)

In the title compound, C20H13BF2N4O, the central fused three-ring oxadi­aza­borininona­phthyridine system is planar (r.m.s. deviation of 0.03 Å). The phenyl ring lies in the plane of this ring system, making a dihedral angle of 0.61 (14)°, and is inclined to the pyridine ring by 9.02 (19)°. In the crystal, mol­ecules are connected by C—H⋯F hydrogen bonds, forming chains propagating along the b-axis direction. The chains are linked by offset ππ inter­actions [inter­centroid distance = 3.4550 (13) Å], forming a three-dimensional supra­molecular architecture.

3D view (loading...)
[Scheme 3D1]
Chemical scheme
[Scheme 1]

Structure description

Over the past decade, BF2 complexes have been known to be fluorescent dyes with high fluorescence quantum yields (Zheng et al., 2015[Zheng, J., Huang, F., Li, Y. J., Xu, T. W., Xu, H., Jia, J. H., Ye, Q. & Gao, J. R. (2015). Dyes Pigments, 113, 502-509.]), sharp fluorescence peaks (Du et al., 2014[Du, M. L., Hu, C. Y., Wang, L. F., Li, C., Han, Y. Y., Gan, X., Chen, Y., Mu, W. H., Huang, M. L. & Fu, W. F. (2014). Dalton Trans. 43, 13924-13931.]), high extinction coefficients (Kubota et al., 2010[Kubota, Y., Tsuzuki, T., Funabiki, K., Ebihara, M. & Matsui, M. (2010). Org. Lett. 12, 4010-4013.]) and high chemical stability (Li et al., 2010[Li, H. J., Fu, W. F., Li, L., Gan, X., Mu, W. H., Chen, W. Q., Duan, X. M. & Song, H. B. (2010). Org. Lett. 12, 2924-2927.]). They are widely applied as sensors (Gonçalves, 2009[Gonçalves, M. S. T. (2009). Chem. Rev. 109, 190-212.]; Kobayashi et al., 2010[Kobayashi, H., Ogawa, M., Alford, R., Choyke, P. L. & Urano, Y. (2010). Chem. Rev. 110, 2620-2640.]; Tachikawa et al., 2010[Tachikawa, T., Wang, N., Yamashita, S., Cui, S.-C. & Majima, T. (2010). Angew. Chem. Int. Ed. 49, 8593-8597.]), photodynamic therapy agents (Lovell et al., 2010[Lovell, J. F., Liu, T. W. B., Chen, J. & Zheng, G. (2010). Chem. Rev. 110, 2839-2857.]; Ozlem & Akkaya, 2009[Ozlem, S. & Akkaya, E. U. (2009). J. Am. Chem. Soc. 131, 48-49.]), photo-electric materials (Gomez-Duran et al., 2010[Gómez-Durán, C. F. A., García-Moreno, I., Costela, A., Martin, V., Sastre, R., Bañuelos, J., López Arbeloa, F., López Arbeloa, I. & Peña-Cabrera, E. (2010). Chem. Commun. 46, 5103-5105.]; Lovell et al., 2010[Lovell, J. F., Liu, T. W. B., Chen, J. & Zheng, G. (2010). Chem. Rev. 110, 2839-2857.]; Ortiz et al., 2010[Ortiz, M. J., Garcia-Moreno, I., Agarrabeitia, A. R., Duran-Sampedro, G., Costela, A., Sastre, R., López Arbeloa, F., Bañuelos Prieto, J. & López Arbeloa, I. (2010). Phys. Chem. Chem. Phys. 12, 7804-7811.]; Ozlem & Akkaya, 2008[Ozlem, S. & Akkaya, E. U. (2009). J. Am. Chem. Soc. 131, 48-49.]) and light-harvesting materials (Erten-Ela et al., 2008[Erten-Ela, S., Yilmaz, M. D., Icli, B., Dede, Y., Icli, S. & Akkaya, E. U. (2008). Org. Lett. 10, 3299-3302.]; Rousseau et al., 2009[Rousseau, T., Cravino, A., Bura, T., Ulrich, G., Ziessel, R. & Roncali, J. (2009). J. Mater. Chem. 19, 2298-2300.]). 1,8-Naphthyridines have attracted inter­est due to their diverse coordination modes and have been used as ion probes (Liu et al., 2014[Liu, X. J., Chen, M. X., Liu, Z. P., Yu, M. M., Wei, L. H. & Li, Z. X. (2014). Tetrahedron, 70, 658-663.]), as luminescent materials (Li et al., 2014[Li, Z., Lv, X., Chen, Y. & Fu, W.-F. (2014). Dyes Pigments, 105, 157-162.]) and in biochemistry (Zhao et al., 2014[Zhao, X. Z., Smith, S. J., Métifiot, M., Marchand, C., Boyer, P. L., Pommier, Y., Hughes, S. H. & Burke, T. R. (2014). J. Med. Chem. 57, 6885-6885.]). The above observations prompted us to synthesize the title compound, which is a novel BF2 complex based on a 1,8-naphthyridine derivative, and we report herein on its crystal structure.

The mol­ecular structure of the title compound is shown in Fig. 1[link]. It contains naphthyridine, pyridyl and phenyl rings. The naphthyridine ring system is fused with a di­fluoro­roxadi­aza­borinino unit. The fused oxadi­aza­borininona­phthyridine ring system is planar (r.m.s. deviation of 0.03 Å). The phenyl ring (C1–C6) lies in the plane of this ring system, making a dihedral angle of 0.61 (14)°, and is inclined to the pyridine ring (N4/C16–C20) by 9.02 (19)°.

[Figure 1]
Figure 1
The mol­ecular structure of the title compound, showing the atom labelling. Displacement ellipsoids are drawn at the 50% probability level

In the crystal, mol­ecules are linked by C—H⋯F hydrogen bonds, forming chains along the b-axis direction (Fig. 2[link] and Table 1[link]). The chains are linked via offset ππ inter­actions [Cg2⋯Cg5i = 3.519 (2) Å, inter­planar distance = 3.4550 (13) Å, slippage = 0.629 Å; Cg2 and Cg5 are the centroids of rings N2/C8–C11/C15 and C1–C6, respectively; symmetry code: (i) x − [{1\over 2}], −y + [{1\over 2}], z − [{1\over 2}]], forming a three-dimensional supra­molecular architecture (Fig. 3[link]).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C10—H10⋯F2i 0.93 2.47 3.353 (4) 160
Symmetry code: (i) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{3\over 2}}].
[Figure 2]
Figure 2
A view along the a axis of the crystal packing of the title compound. Hydrogen bonds are shown as dashed lines (Table 1[link]).
[Figure 3]
Figure 3
A view along the c axis of the crystal packing of the title compound. Hydrogen bonds are shown as dashed lines (Table 1[link]) and, of the H atoms, only H10 is shown for clarity.

Owing to the shortage of BF2 complexes based on 1,8-naphthyridine derivatives, there are few examples of similar compounds in the literature. A search of the Cambridge Structural Database (Version 5.37, November 2015; Groom et al., 2016[Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171-179.]) revealed the structure of one very similar compound viz. 1,1-di­fluoro-7,9-dimethyl-3-phenyl-1H-[1,3,5,2]oxadi­aza­borinino-[3,4-a][1,8] naphthyridin-11-ium-1-uide (Wu et al., 2012[Wu, Y. Y., Chen, Y., Gou, G. Z., Mu, W. H., Lv, X. J., Du, M. L. & Fu, W. F. (2012). Org. Lett. 14, 5226-5229.]).

Synthesis and crystallization

BF3·OEt2 (2 ml, 16 mmol) was added dropwise to an ice-cooled solution of 2,6-lutidine (1 ml) and N-[7-(pyridin-2-yl)-1,8-naphthyridin-2-yl]benzamide (0.326 g,1 mmol) in anhydrous CH2Cl2 (80 ml) under a nitro­gen atmosphere. After the mixture was stirred for 24 h at room temperature, the reaction was quenched by 20 ml distilled water. The aqueous layer was extracted with CH2Cl2 (3 × 100 ml), the organic layer was dried with Na2SO4 and the solvent was removed under reduced pressure. The residue was purified by silica gel chromatography using CH2Cl2 as eluent to give the pure product as a bright-yellow powder (yield 0.184 g, 50%). Crystals of the title compound were obtained from the CH2Cl2 solution by slow evaporation of the solvent at room temperature.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2[link].

Table 2
Experimental details

Crystal data
Chemical formula C20H13BF2N4O
Mr 374.15
Crystal system, space group Monoclinic, P21/n
Temperature (K) 293
a, b, c (Å) 10.144 (2), 16.276 (3), 10.491 (2)
β (°) 101.27 (3)
V3) 1698.8 (6)
Z 4
Radiation type Mo Kα
μ (mm−1) 0.11
Crystal size (mm) 0.28 × 0.26 × 0.24
 
Data collection
Diffractometer Rigaku R-AXIS RAPID
Absorption correction Multi-scan (ABSCOR; Higashi, 1995[Higashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan.])
Tmin, Tmax 0.970, 0.975
No. of measured, independent and observed [I > 2σ(I)] reflections 14275, 3328, 1795
Rint 0.058
(sin θ/λ)max−1) 0.617
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.069, 0.233, 1.05
No. of reflections 3328
No. of parameters 253
No. of restraints 4
H-atom treatment H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.45, −0.36
Computer programs: PROCESS-AUTO (Rigaku, 1998[Rigaku (1998). PROCESS-AUTO. Rigaku Corporation, Tokyo, Japan.]), CrystalStructure (Rigaku/MSC, 2006[Rigaku/MSC (2006). CrystalStructure. Rigaku/MSC, The Woodlands, Texas, USA.]), SHELXS97 and SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Structural data


Computing details top

Data collection: PROCESS-AUTO (Rigaku, 1998); cell refinement: PROCESS-AUTO (Rigaku, 1998); data reduction: CrystalStructure (Rigaku/MSC, 2006); 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: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

1,1-Difluoro-3-phenyl-9-(pyridin-2-yl)-1H-1λ4,11λ4-1,3,5,2-oxadiazaborinino[3,4-a][1,8]naphthyridine top
Crystal data top
C20H13BF2N4OF(000) = 768
Mr = 374.15Dx = 1.463 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 3328 reflections
a = 10.144 (2) Åθ = 3.1–26.0°
b = 16.276 (3) ŵ = 0.11 mm1
c = 10.491 (2) ÅT = 293 K
β = 101.27 (3)°Blcok, yellow
V = 1698.8 (6) Å30.28 × 0.26 × 0.24 mm
Z = 4
Data collection top
Rigaku R-AXIS RAPID
diffractometer
3328 independent reflections
Radiation source: fine-focus sealed tube1795 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.058
ω scansθmax = 26.0°, θmin = 3.1°
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
h = 1212
Tmin = 0.970, Tmax = 0.975k = 2020
14275 measured reflectionsl = 1212
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)] = 0.069Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.233H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.1317P)2 + 0.0306P]
where P = (Fo2 + 2Fc2)/3
3328 reflections(Δ/σ)max < 0.001
253 parametersΔρmax = 0.45 e Å3
4 restraintsΔρmin = 0.36 e Å3
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*/Ueq
B10.3307 (4)0.1319 (2)0.8391 (4)0.0577 (10)
F10.27253 (19)0.09215 (12)0.9281 (2)0.0773 (7)
F20.3042 (2)0.09408 (11)0.7184 (2)0.0786 (7)
N10.5098 (3)0.27104 (16)0.9010 (3)0.0570 (7)
N20.2844 (3)0.22483 (15)0.8257 (2)0.0504 (7)
N30.0659 (3)0.17947 (15)0.7507 (3)0.0535 (7)
N40.0920 (3)0.0434 (2)0.6740 (4)0.0949 (12)
O10.4774 (2)0.13081 (12)0.8848 (3)0.0672 (7)
C10.7405 (3)0.0970 (2)0.9777 (4)0.0613 (9)
H10.67900.05430.95770.074*
C20.8750 (4)0.0794 (2)1.0225 (4)0.0719 (11)
H20.90420.02521.03260.086*
C30.9666 (4)0.1439 (3)1.0526 (4)0.0727 (11)
H31.05720.13241.08190.087*
C40.9246 (4)0.2231 (3)1.0396 (4)0.0715 (11)
H40.98650.26551.06050.086*
C50.7901 (3)0.2411 (2)0.9953 (3)0.0621 (9)
H50.76180.29550.98760.075*
C60.6967 (3)0.17794 (19)0.9622 (3)0.0531 (8)
C70.5527 (3)0.19527 (19)0.9122 (3)0.0552 (8)
C80.3758 (4)0.28545 (19)0.8567 (3)0.0549 (8)
C90.3336 (4)0.36894 (19)0.8446 (4)0.0636 (9)
H90.39620.41060.86870.076*
C100.2031 (4)0.3884 (2)0.7983 (3)0.0640 (10)
H100.17710.44320.78950.077*
C110.1074 (3)0.32651 (18)0.7638 (3)0.0546 (8)
C120.0303 (4)0.3392 (2)0.7114 (3)0.0659 (10)
H120.06280.39240.69570.079*
C130.1156 (4)0.2745 (2)0.6837 (3)0.0646 (10)
H130.20670.28280.65160.077*
C140.0629 (3)0.1947 (2)0.7048 (3)0.0563 (9)
C150.1487 (3)0.24382 (18)0.7802 (3)0.0496 (8)
C160.1497 (3)0.1216 (2)0.6737 (3)0.0572 (8)
C170.2834 (3)0.1330 (2)0.6458 (3)0.0524 (8)
H170.32030.18530.64560.063*
C180.3609 (4)0.0675 (3)0.6185 (4)0.0758 (11)
H180.45350.07530.60160.091*
C190.3142 (4)0.0101 (3)0.6137 (4)0.0780 (12)
H190.37310.05380.59100.094*
C200.1784 (4)0.0228 (2)0.6429 (5)0.0837 (12)
H200.14400.07570.64190.100*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
B10.057 (2)0.0370 (19)0.076 (3)0.0016 (17)0.004 (2)0.0001 (18)
F10.0656 (13)0.0590 (12)0.1045 (17)0.0053 (10)0.0094 (12)0.0308 (11)
F20.0820 (14)0.0531 (12)0.0938 (16)0.0081 (10)0.0004 (12)0.0231 (11)
N10.0582 (17)0.0447 (15)0.0673 (18)0.0051 (13)0.0103 (14)0.0005 (13)
N20.0567 (16)0.0411 (14)0.0544 (16)0.0004 (12)0.0133 (13)0.0007 (11)
N30.0548 (16)0.0471 (16)0.0562 (17)0.0044 (13)0.0046 (13)0.0014 (12)
N40.087 (2)0.0626 (16)0.127 (3)0.0002 (13)0.003 (2)0.010 (2)
O10.0544 (14)0.0393 (12)0.1033 (19)0.0023 (10)0.0044 (13)0.0031 (12)
C10.055 (2)0.057 (2)0.072 (2)0.0048 (16)0.0136 (17)0.0061 (17)
C20.064 (2)0.069 (2)0.082 (3)0.0039 (19)0.013 (2)0.001 (2)
C30.054 (2)0.088 (3)0.078 (3)0.003 (2)0.0167 (18)0.002 (2)
C40.063 (2)0.079 (3)0.073 (3)0.023 (2)0.0134 (19)0.004 (2)
C50.062 (2)0.058 (2)0.065 (2)0.0068 (17)0.0100 (17)0.0013 (17)
C60.057 (2)0.0548 (19)0.0487 (19)0.0083 (16)0.0122 (15)0.0020 (15)
C70.064 (2)0.0468 (18)0.055 (2)0.0083 (16)0.0139 (16)0.0018 (15)
C80.072 (2)0.0411 (17)0.054 (2)0.0048 (16)0.0174 (17)0.0001 (14)
C90.081 (2)0.0392 (17)0.074 (2)0.0091 (17)0.026 (2)0.0030 (16)
C100.085 (3)0.0416 (17)0.070 (2)0.0082 (18)0.026 (2)0.0065 (16)
C110.070 (2)0.0410 (17)0.054 (2)0.0042 (16)0.0153 (17)0.0020 (14)
C120.079 (3)0.053 (2)0.067 (2)0.0212 (19)0.0168 (19)0.0050 (17)
C130.064 (2)0.064 (2)0.064 (2)0.0207 (19)0.0080 (18)0.0035 (18)
C140.062 (2)0.0571 (19)0.050 (2)0.0088 (17)0.0111 (16)0.0020 (15)
C150.0597 (19)0.0423 (17)0.0487 (18)0.0033 (15)0.0153 (15)0.0007 (14)
C160.0476 (13)0.0684 (17)0.0537 (19)0.0024 (15)0.0051 (14)0.0013 (16)
C170.0486 (13)0.0595 (18)0.0468 (18)0.0159 (12)0.0034 (14)0.0014 (14)
C180.053 (2)0.092 (3)0.078 (3)0.0055 (17)0.0013 (18)0.007 (2)
C190.064 (3)0.078 (3)0.085 (3)0.011 (2)0.003 (2)0.001 (2)
C200.072 (3)0.062 (2)0.110 (3)0.0032 (16)0.001 (2)0.001 (2)
Geometric parameters (Å, º) top
B1—F11.362 (5)C3—C41.355 (6)
B1—F21.386 (5)C4—C51.384 (5)
B1—O11.472 (5)C5—C61.395 (4)
B1—N21.582 (4)C6—C71.480 (5)
N1—C71.306 (4)C8—C91.423 (5)
N1—C81.368 (4)C9—C101.356 (5)
N2—C81.350 (4)C10—C111.396 (5)
N2—C151.400 (4)C11—C151.410 (4)
N3—C141.325 (4)C11—C121.413 (5)
N3—C151.341 (4)C12—C131.358 (5)
N4—C201.387 (5)C13—C141.405 (5)
N4—C161.400 (5)C14—C161.478 (5)
O1—C71.296 (4)C16—C171.344 (4)
C1—C21.383 (5)C17—C181.322 (5)
C1—C61.390 (5)C18—C191.353 (5)
C2—C31.396 (5)C19—C201.367 (5)
F1—B1—F2112.6 (3)N2—C8—N1123.2 (3)
F1—B1—O1108.5 (3)N2—C8—C9119.7 (3)
F2—B1—O1107.2 (3)N1—C8—C9117.1 (3)
F1—B1—N2110.7 (3)C10—C9—C8120.7 (3)
F2—B1—N2110.0 (3)C9—C10—C11120.4 (3)
O1—B1—N2107.7 (3)C10—C11—C15118.8 (3)
C7—N1—C8119.0 (3)C10—C11—C12125.4 (3)
C8—N2—C15120.3 (3)C15—C11—C12115.8 (3)
C8—N2—B1120.0 (3)C13—C12—C11120.7 (3)
C15—N2—B1119.7 (3)C12—C13—C14118.5 (3)
C14—N3—C15117.8 (3)N3—C14—C13123.2 (3)
C20—N4—C16117.4 (3)N3—C14—C16115.6 (3)
C7—O1—B1125.2 (3)C13—C14—C16121.2 (3)
C2—C1—C6120.4 (3)N3—C15—N2115.9 (3)
C1—C2—C3119.4 (4)N3—C15—C11124.0 (3)
C4—C3—C2120.6 (4)N2—C15—C11120.1 (3)
C3—C4—C5120.3 (4)C17—C16—N4122.0 (3)
C4—C5—C6120.3 (3)C17—C16—C14118.0 (3)
C1—C6—C5118.9 (3)N4—C16—C14120.0 (3)
C1—C6—C7119.5 (3)C18—C17—C16117.9 (3)
C5—C6—C7121.5 (3)C17—C18—C19124.2 (4)
O1—C7—N1125.0 (3)C18—C19—C20118.5 (4)
O1—C7—C6115.0 (3)C19—C20—N4119.9 (4)
N1—C7—C6120.0 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C10—H10···F2i0.932.473.353 (4)160
Symmetry code: (i) x+1/2, y+1/2, z+3/2.
 

Acknowledgements

Support from the `Spring Sunshine' Plan of Ministry of Education of China (grant No. Z2011125) and the National Natural Science Foundation of China (grant No. 21262049).

References

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