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

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ISSN: 2056-9890

N-(7-Methyl-1,8-naphthyridin-2-yl)acetamide–acetic acid (1/1)

aCollege of Chemistry and Chemical Engineering, Yunnan Normal University, Kunming 650500, People's Republic of China, bSchool of Computer Science and Technology, Harbin Institute of Technology, Harbin 150001, People's Republic of China, and cSchool of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia
*Correspondence e-mail: chishaoming@gmail.com

(Received 19 February 2013; accepted 23 February 2013; online 6 March 2013)

In the title adduct, C11H11N3O·C2H4O2, all non-H atoms of the acetamide mol­ecule are roughly coplanar, with an r.m.s. deviation of 0.0720 Å. The dihedral angle between the ring plane and the acetamide group is 8.5 (2)°. In the crystal, O—H⋯N and N—H⋯O hydrogen bonds link the acetamide and acetic acid mol­ecules.

Related literature

For the synthesis of 7-amino-2-methyl-1,8-naphthyridine, see: Brown (1965[Brown, E. V. (1965). J. Org. Chem. 30, 1607-1610.]); Henry & Hammond (1977[Henry, R. A. & Hammond, P. R. (1977). J. Heterocycl. Chem. pp. 1109-1114.]). For the coordination modes of 1,8-naphthyridine ligands, see: Zong et al. (2004[Zong, R. F., Naud, F., Segal, C., Burke, J., Wu, F. Y. & Thummel, R. (2004). Inorg. Chem. 43, 6195-6202.]); Zúñiga et al. (2011[Zúñiga, C., Moya, S. A., Fuentealba, M., Aranda, B. & Aguirre, P. (2011). Inorg. Chem. Commun. 14, 964-967.]); Li et al. (2011[Li, Z. X., Li, C., Mu, W. H., Xiong, S. X. & Fu, W. F. (2011). Inorg. Chim. Acta, 379, 7-15.]); Gan et al. (2011[Gan, X., Chi, S. M., Mu, W. H., Yao, J. C., Quan, L., Li, C., Bian, Z. Y., Chen, Y. & Fu, W. F. (2011). Dalton Trans. 40, 7365-7374.]). For their biological activity, see: Sivakumar et al. (2011[Sivakumar, P., Iyer, G. & Doble, M. (2011). Med. Chem. Res. pp. 1-8.]); Roma et al. (2000[Roma, G., Braccio, M. D., Grossi, G., Mattioli, F. & Ghia, M. (2000). Eur. J. Med. Chem. 35, 1021-1026.]); Badawneh et al. (2001[Badawneh, M., Ferrarini, P. L., Calderone, V., Manera, C., Martinotti, E., Mori, C., Saccomanni, G. & Testai, L. (2001). Eur. J. Med. Chem. 36, 925-934.]); Nagasawa et al. (2011[Nagasawa, J. Y., Song, J., Chen, H., Kim, H. W., Blazel, J., Ouk, S., Groschel, B., Borges, V., Ong, V., Yeh, L. T., Girardet, J. L., Vernier, J. M., Raney, A. K. & Pinkerton, A. B. (2011). Bioorg. Med. Chem. Lett. 21, 760-763.]); Capozzi et al. (2012[Capozzi, A., Mantuano, E., Matarrese, P., Saccomanni, G., Manera, C., Mattei, V., Gambardella, L., Malorni, W., Sorice, M. & Misasi, R. (2012). Anticancer Agents Med. Chem. 12, 653-662.]).

[Scheme 1]

Experimental

Crystal data
  • C11H11N3O·C2H4O2

  • Mr = 261.28

  • Triclinic, [P \overline 1]

  • a = 8.3628 (17) Å

  • b = 9.0904 (18) Å

  • c = 9.5093 (19) Å

  • α = 71.30 (3)°

  • β = 76.43 (3)°

  • γ = 78.64 (3)°

  • V = 659.8 (2) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 293 K

  • 0.15 × 0.10 × 0.07 mm

Data collection
  • Rigaku R-AXIS RAPID diffractometer

  • Absorption correction: multi-scan (ABSCOR; Higashi, 1995[Higashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.986, Tmax = 0.993

  • 5757 measured reflections

  • 2591 independent reflections

  • 1014 reflections with I > 2σ(I)

  • Rint = 0.058

Refinement
  • R[F2 > 2σ(F2)] = 0.047

  • wR(F2) = 0.160

  • S = 0.91

  • 2591 reflections

  • 172 parameters

  • H-atom parameters constrained

  • Δρmax = 0.21 e Å−3

  • Δρmin = −0.20 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O3—H3A⋯N2i 0.82 1.96 2.774 (3) 173
N1—H1A⋯O2ii 0.86 2.07 2.931 (3) 178
Symmetry codes: (i) x+1, y-1, z; (ii) x-1, y+1, z.

Data collection: PROCESS-AUTO (Rigaku, 1998[Rigaku (1998). PROCESS-AUTO. Rigaku Corporation, Tokyo, Japan.]); cell refinement: PROCESS-AUTO; data reduction: CrystalStructure (Rigaku/MSC, 2006[Rigaku/MSC (2006). CrystalStructure. Rigaku/MSC, The Woodlands, Texas, USA.]); 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: DIAMOND (Brandenburg, 1999[Brandenburg, K. (1999). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

The structure and chemical properties of the 1,8-naphthyridine ring system are interesting to both synthetic and pharmaceutical organic chemists. They can act as monodendate, chelating bidendate and dinuclear bridging ligands(Zong et al., 2004; Zúñiga et al., 2011; Li et al., 2011; Gan et al., 2011). They have also found use as anti-bacterial(Sivakumar et al., 2011), anti-inflammatory(Roma et al., 2000), anti-hypertensive(Badawneh et al., 2001) and anti-cancer drugs(Nagasawa et al., 2011; Capozzi et al., 2012). Herein we report the synthesis and structure of the title co-crystal, C11H11N3O.C2H4O2.

The structure of the title complex is shown in Fig. 1 and Fig. 2 and the hydrogen-bond geometry is given in Table. 1. The planes defined by 7-acetamino-2–methyl-1,8-naphthyridine and acetic acid have root mean square (r.m.s.) deviations of 0.0720 Å and 0.0014 Å and the angle between the planes is 8.66 (19) °. There are two, O—H···N and N—H···O, intermolecular hydrogen bonds between 7-acetamino-2-methyl-1,8-naphthyridine and acetic acid, which link the molecules to form layered units. The O(3)···N(2) and N(1)···O(2) distances are 2.782 (4) and 2.941 (4) Å and the angles O(3)—H(3A)···N(2) and N(1)—H(1A)···O(2) are 173.1 (4)° and 178.0 (2)°. The complementarity of the hydrogen-bonding interactions make the hydrogen-bonded units stable. The stability of these units may explain the difficulty in separating the two components via chromatography. The distances between the adjacent parallel planes are 2.960 (4) and 3.349 (4) Å. The weak C—H···N contacts have a H···N distance of 2.666 (3) Å.

Related literature top

For the synthesis of 7-amino-2-methyl-1,8-naphthyridine, see: Brown (1965); Henry & Hammond (1977). For the coordination modes of 1,8-naphthyridine ligands, see: Zong et al. (2004); Zúñiga et al. (2011); Li et al. (2011); Gan et al. (2011). For their biological activity, see: Sivakumar et al. (2011); Roma et al. (2000); Badawneh et al. (2001); Nagasawa et al. (2011); Capozzi et al. (2012).

Experimental top

7-amino-2-methyl-1,8-naphthyridine(Brown, 1965; Henry & Hammond, 1977)(4.00 g, 0.025 mol) was added to an acetic anhydride (15 ml) solution in an atmosphere of nitrogen. The mixture was stirred at room temperature for 1 h. Followed by slow cooling to room temperature which gave flaky straw-colored crystals. Yield: 3.97 g (78%). In the co-crystal complex, the acetic acid component is formed from the reagent (acetic anhydride) used.

Refinement top

H atoms were placed in calculated positions. The H atoms were constrained to an ideal geometry (C—H =0.96 Å, N—H =0.86 Å and O—H = 0.85 Å) and refined as riding atoms with Uiso(H) = 1.2Ueq(C) or 1.5Ueq(methyl C), Uiso(H) = 1.2Ueq(N) and Uiso(H) = 1.5Ueq(O).

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: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title complex with atom labels and 30% probability displacement ellipsoids.
[Figure 2] Fig. 2. A view of the crystal packing. Hydrogen bonds are shown as black dashed lines, while weak contacts as blue ones.
N-(7-Methyl-1,8-naphthyridin-2-yl)acetamide–acetic acid (1/1) top
Crystal data top
C11H11N3O·C2H4O2Z = 2
Mr = 261.28F(000) = 276
Triclinic, P1Dx = 1.315 Mg m3
a = 8.3628 (17) ÅMo Kα radiation, λ = 0.71073 Å
b = 9.0904 (18) ÅCell parameters from 25 reflections
c = 9.5093 (19) Åθ = 3.1–26.0°
α = 71.30 (3)°µ = 0.10 mm1
β = 76.43 (3)°T = 293 K
γ = 78.64 (3)°Flaky, yellow
V = 659.8 (2) Å30.15 × 0.10 × 0.07 mm
Data collection top
Rigaku R-AXIS RAPID
diffractometer
2591 independent reflections
Radiation source: fine-focus sealed tube1014 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.058
ω scansθmax = 26.0°, θmin = 3.1°
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
h = 1010
Tmin = 0.986, Tmax = 0.993k = 1110
5757 measured reflectionsl = 1111
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)] = 0.047Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.160H-atom parameters constrained
S = 0.91 w = 1/[σ2(Fo2) + (0.0724P)2]
where P = (Fo2 + 2Fc2)/3
2591 reflections(Δ/σ)max < 0.001
172 parametersΔρmax = 0.21 e Å3
0 restraintsΔρmin = 0.20 e Å3
Crystal data top
C11H11N3O·C2H4O2γ = 78.64 (3)°
Mr = 261.28V = 659.8 (2) Å3
Triclinic, P1Z = 2
a = 8.3628 (17) ÅMo Kα radiation
b = 9.0904 (18) ŵ = 0.10 mm1
c = 9.5093 (19) ÅT = 293 K
α = 71.30 (3)°0.15 × 0.10 × 0.07 mm
β = 76.43 (3)°
Data collection top
Rigaku R-AXIS RAPID
diffractometer
2591 independent reflections
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
1014 reflections with I > 2σ(I)
Tmin = 0.986, Tmax = 0.993Rint = 0.058
5757 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0470 restraints
wR(F2) = 0.160H-atom parameters constrained
S = 0.91Δρmax = 0.21 e Å3
2591 reflectionsΔρmin = 0.20 e Å3
172 parameters
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*/Ueq
N20.0316 (3)0.2121 (2)0.5279 (2)0.0452 (6)
N30.2361 (3)0.1068 (3)0.3663 (3)0.0504 (7)
O30.9707 (3)0.5868 (2)0.2515 (2)0.0681 (7)
H3A0.98220.64170.33660.102*
C60.1937 (4)0.0352 (3)0.6338 (3)0.0449 (8)
C100.1549 (4)0.0928 (3)0.5099 (3)0.0462 (8)
C30.0509 (4)0.2067 (3)0.6651 (3)0.0476 (8)
C40.0218 (4)0.0819 (3)0.7965 (3)0.0551 (9)
H4A0.08380.08180.89150.066*
O20.7624 (3)0.4612 (2)0.3776 (3)0.0735 (8)
C50.1006 (4)0.0375 (3)0.7772 (3)0.0541 (9)
H5A0.12230.12130.86030.065*
N10.1743 (3)0.3336 (3)0.6728 (3)0.0537 (8)
H1A0.19480.39490.58720.064*
O10.2586 (3)0.2989 (3)0.9261 (2)0.0799 (8)
C70.3229 (4)0.1511 (3)0.6026 (4)0.0559 (9)
H7A0.35330.23690.68080.067*
C120.8447 (4)0.4767 (3)0.2609 (4)0.0577 (9)
C80.4028 (4)0.1383 (3)0.4598 (4)0.0564 (9)
H8A0.48780.21530.43840.068*
C10.3839 (4)0.5235 (3)0.7581 (3)0.0659 (10)
H1B0.44530.54630.84920.099*
H1C0.45940.51170.70160.099*
H1D0.32150.60790.69840.099*
C90.3559 (4)0.0064 (3)0.3426 (3)0.0504 (8)
C110.4429 (5)0.0117 (4)0.1835 (4)0.0734 (11)
H11A0.39590.10730.11910.110*
H11B0.43020.07540.15260.110*
H11C0.55870.01500.17610.110*
C20.2675 (4)0.3748 (3)0.7971 (4)0.0549 (9)
C130.8161 (5)0.3725 (4)0.1088 (4)0.0802 (12)
H13A0.72300.29390.12090.120*
H13B0.79380.43390.05190.120*
H13C0.91310.32290.05610.120*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N20.0466 (16)0.0427 (13)0.0422 (14)0.0025 (11)0.0123 (12)0.0088 (10)
N30.0497 (17)0.0534 (14)0.0479 (15)0.0011 (13)0.0106 (13)0.0165 (11)
O30.0696 (17)0.0648 (13)0.0544 (14)0.0067 (12)0.0116 (12)0.0051 (10)
C60.049 (2)0.0403 (15)0.0454 (17)0.0008 (14)0.0183 (15)0.0089 (13)
C100.046 (2)0.0418 (16)0.0518 (19)0.0017 (14)0.0195 (16)0.0124 (14)
C30.050 (2)0.0474 (16)0.0463 (18)0.0025 (14)0.0161 (15)0.0150 (13)
C40.069 (2)0.0499 (16)0.0403 (16)0.0040 (16)0.0168 (16)0.0073 (13)
O20.0814 (19)0.0733 (15)0.0530 (15)0.0150 (13)0.0145 (14)0.0142 (12)
C50.063 (2)0.0435 (16)0.0499 (19)0.0003 (15)0.0160 (17)0.0061 (13)
N10.0588 (19)0.0493 (13)0.0455 (14)0.0120 (13)0.0159 (13)0.0103 (11)
O10.093 (2)0.0765 (15)0.0464 (14)0.0227 (14)0.0069 (12)0.0092 (11)
C70.055 (2)0.0464 (17)0.063 (2)0.0073 (15)0.0226 (17)0.0115 (14)
C120.061 (2)0.0537 (18)0.052 (2)0.0009 (17)0.0167 (18)0.0058 (15)
C80.054 (2)0.0514 (17)0.065 (2)0.0060 (16)0.0167 (18)0.0213 (15)
C10.062 (2)0.0562 (19)0.063 (2)0.0124 (17)0.0070 (18)0.0096 (16)
C90.047 (2)0.0543 (18)0.0519 (19)0.0030 (15)0.0084 (16)0.0209 (15)
C110.068 (3)0.079 (2)0.070 (2)0.007 (2)0.007 (2)0.0303 (18)
C20.052 (2)0.0570 (18)0.0480 (19)0.0035 (16)0.0085 (16)0.0122 (15)
C130.083 (3)0.076 (2)0.064 (2)0.000 (2)0.024 (2)0.0049 (18)
Geometric parameters (Å, º) top
N2—C31.315 (3)O1—C21.211 (3)
N2—C101.365 (3)C7—C81.344 (4)
N3—C91.322 (3)C7—H7A0.9300
N3—C101.353 (3)C12—C131.497 (4)
O3—C121.310 (3)C8—C91.413 (4)
O3—H3A0.8200C8—H8A0.9300
C6—C51.399 (4)C1—C21.498 (4)
C6—C71.402 (4)C1—H1B0.9600
C6—C101.414 (3)C1—H1C0.9600
C3—N11.397 (3)C1—H1D0.9600
C3—C41.426 (4)C9—C111.489 (4)
C4—C51.364 (4)C11—H11A0.9600
C4—H4A0.9300C11—H11B0.9600
O2—C121.195 (3)C11—H11C0.9600
C5—H5A0.9300C13—H13A0.9600
N1—C21.371 (3)C13—H13B0.9600
N1—H1A0.8600C13—H13C0.9600
C3—N2—C10118.3 (2)C7—C8—C9119.2 (3)
C9—N3—C10117.6 (2)C7—C8—H8A120.4
C12—O3—H3A109.5C9—C8—H8A120.4
C5—C6—C7125.0 (3)C2—C1—H1B109.5
C5—C6—C10118.0 (2)C2—C1—H1C109.5
C7—C6—C10117.0 (3)H1B—C1—H1C109.5
N3—C10—N2115.3 (2)C2—C1—H1D109.5
N3—C10—C6123.0 (2)H1B—C1—H1D109.5
N2—C10—C6121.7 (3)H1C—C1—H1D109.5
N2—C3—N1114.4 (2)N3—C9—C8123.1 (3)
N2—C3—C4124.0 (2)N3—C9—C11116.5 (3)
N1—C3—C4121.7 (3)C8—C9—C11120.4 (3)
C5—C4—C3117.3 (3)C9—C11—H11A109.5
C5—C4—H4A121.3C9—C11—H11B109.5
C3—C4—H4A121.3H11A—C11—H11B109.5
C4—C5—C6120.7 (3)C9—C11—H11C109.5
C4—C5—H5A119.7H11A—C11—H11C109.5
C6—C5—H5A119.7H11B—C11—H11C109.5
C2—N1—C3129.4 (2)O1—C2—N1124.0 (3)
C2—N1—H1A115.3O1—C2—C1122.8 (3)
C3—N1—H1A115.3N1—C2—C1113.3 (3)
C8—C7—C6120.1 (3)C12—C13—H13A109.5
C8—C7—H7A120.0C12—C13—H13B109.5
C6—C7—H7A120.0H13A—C13—H13B109.5
O2—C12—O3123.8 (3)C12—C13—H13C109.5
O2—C12—C13123.9 (3)H13A—C13—H13C109.5
O3—C12—C13112.2 (3)H13B—C13—H13C109.5
C9—N3—C10—N2179.5 (3)C7—C6—C5—C4179.3 (3)
C9—N3—C10—C60.7 (4)C10—C6—C5—C41.1 (5)
C3—N2—C10—N3179.2 (3)N2—C3—N1—C2170.8 (3)
C3—N2—C10—C60.6 (4)C4—C3—N1—C210.3 (5)
C5—C6—C10—N3179.7 (3)C5—C6—C7—C8179.0 (3)
C7—C6—C10—N30.0 (4)C10—C6—C7—C80.6 (5)
C5—C6—C10—N20.6 (4)C6—C7—C8—C90.6 (5)
C7—C6—C10—N2179.8 (3)C10—N3—C9—C80.7 (4)
C10—N2—C3—N1179.9 (3)C10—N3—C9—C11179.8 (3)
C10—N2—C3—C41.3 (5)C7—C8—C9—N30.0 (5)
N2—C3—C4—C50.8 (5)C7—C8—C9—C11179.5 (3)
N1—C3—C4—C5179.5 (3)C3—N1—C2—O12.5 (5)
C3—C4—C5—C60.5 (5)C3—N1—C2—C1177.9 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3A···N2i0.821.962.774 (3)173
N1—H1A···O2ii0.862.072.931 (3)178
Symmetry codes: (i) x+1, y1, z; (ii) x1, y+1, z.

Experimental details

Crystal data
Chemical formulaC11H11N3O·C2H4O2
Mr261.28
Crystal system, space groupTriclinic, P1
Temperature (K)293
a, b, c (Å)8.3628 (17), 9.0904 (18), 9.5093 (19)
α, β, γ (°)71.30 (3), 76.43 (3), 78.64 (3)
V3)659.8 (2)
Z2
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.15 × 0.10 × 0.07
Data collection
DiffractometerRigaku R-AXIS RAPID
diffractometer
Absorption correctionMulti-scan
(ABSCOR; Higashi, 1995)
Tmin, Tmax0.986, 0.993
No. of measured, independent and
observed [I > 2σ(I)] reflections
5757, 2591, 1014
Rint0.058
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.047, 0.160, 0.91
No. of reflections2591
No. of parameters172
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.21, 0.20

Computer programs: PROCESS-AUTO (Rigaku, 1998), CrystalStructure (Rigaku/MSC, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3A···N2i0.821.962.774 (3)173.1
N1—H1A···O2ii0.862.072.931 (3)178.2
Symmetry codes: (i) x+1, y1, z; (ii) x1, y+1, z.
 

Acknowledgements

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

References

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