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

Gou, G.-Z.; Ma, R.; Zhou, Q.-D.; Chi, S.-M.

doi:10.1107/S1600536813005242

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 69| Part 4| April 2013| Page o489

doi:10.1107/S1600536813005242

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

Gao-Zhang Gou,^a Rui Ma,^b Qing-Di Zhou ^c and Shao-Ming Chi ^a ^*

^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 ); 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

Crystal data

C₁₁H₁₁N₃O·C₂H₄O₂
M_r = 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 ) T_min = 0.986, T_max = 0.993
5757 measured reflections
2591 independent reflections
1014 reflections with I > 2σ(I)
R_int = 0.058

Refinement

R[F² > 2σ(F²)] = 0.047
wR(F²) = 0.160
S = 0.91
2591 reflections
172 parameters
H-atom parameters constrained
Δρ_max = 0.21 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	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 ); cell refinement: PROCESS-AUTO; 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.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536813005242/qm2092sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813005242/qm2092Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536813005242/qm2092Isup3.cml

checkCIF report

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.

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

	Fig. 1. The molecular structure of the title complex with atom labels and 30% probability displacement ellipsoids.
	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·C₂H₄O₂	Z = 2
M_r = 261.28	F(000) = 276
Triclinic, P1	D_x = 1.315 Mg m⁻³
a = 8.3628 (17) Å	Mo Kα radiation, λ = 0.71073 Å
b = 9.0904 (18) Å	Cell parameters from 25 reflections
c = 9.5093 (19) Å	θ = 3.1–26.0°
α = 71.30 (3)°	µ = 0.10 mm⁻¹
β = 76.43 (3)°	T = 293 K
γ = 78.64 (3)°	Flaky, yellow
V = 659.8 (2) Å³	0.15 × 0.10 × 0.07 mm

Data collection top

Rigaku R-AXIS RAPID diffractometer	2591 independent reflections
Radiation source: fine-focus sealed tube	1014 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.058
ω scans	θ_max = 26.0°, θ_min = 3.1°
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	h = −10→10
T_min = 0.986, T_max = 0.993	k = −11→10
5757 measured reflections	l = −11→11

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.047	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.160	H-atom parameters constrained
S = 0.91	w = 1/[σ²(F_o²) + (0.0724P)²] where P = (F_o² + 2F_c²)/3
2591 reflections	(Δ/σ)_max < 0.001
172 parameters	Δρ_max = 0.21 e Å⁻³
0 restraints	Δρ_min = −0.20 e Å⁻³

Crystal data top

C₁₁H₁₁N₃O·C₂H₄O₂	γ = 78.64 (3)°
M_r = 261.28	V = 659.8 (2) Å³
Triclinic, P1	Z = 2
a = 8.3628 (17) Å	Mo Kα radiation
b = 9.0904 (18) Å	µ = 0.10 mm⁻¹
c = 9.5093 (19) Å	T = 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)
T_min = 0.986, T_max = 0.993	R_int = 0.058
5757 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.047	0 restraints
wR(F²) = 0.160	H-atom parameters constrained
S = 0.91	Δρ_max = 0.21 e Å⁻³
2591 reflections	Δρ_min = −0.20 e Å⁻³
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

	x	y	z	U_iso*/U_eq
N2	0.0316 (3)	0.2121 (2)	0.5279 (2)	0.0452 (6)
N3	0.2361 (3)	0.1068 (3)	0.3663 (3)	0.0504 (7)
O3	0.9707 (3)	−0.5868 (2)	0.2515 (2)	0.0681 (7)
H3A	0.9822	−0.6417	0.3366	0.102*
C6	0.1937 (4)	−0.0352 (3)	0.6338 (3)	0.0449 (8)
C10	0.1549 (4)	0.0928 (3)	0.5099 (3)	0.0462 (8)
C3	−0.0509 (4)	0.2067 (3)	0.6651 (3)	0.0476 (8)
C4	−0.0218 (4)	0.0819 (3)	0.7965 (3)	0.0551 (9)
H4A	−0.0838	0.0818	0.8915	0.066*
O2	0.7624 (3)	−0.4612 (2)	0.3776 (3)	0.0735 (8)
C5	0.1006 (4)	−0.0375 (3)	0.7772 (3)	0.0541 (9)
H5A	0.1223	−0.1213	0.8603	0.065*
N1	−0.1743 (3)	0.3336 (3)	0.6728 (3)	0.0537 (8)
H1A	−0.1948	0.3949	0.5872	0.064*
O1	−0.2586 (3)	0.2989 (3)	0.9261 (2)	0.0799 (8)
C7	0.3229 (4)	−0.1511 (3)	0.6026 (4)	0.0559 (9)
H7A	0.3533	−0.2369	0.6808	0.067*
C12	0.8447 (4)	−0.4767 (3)	0.2609 (4)	0.0577 (9)
C8	0.4028 (4)	−0.1383 (3)	0.4598 (4)	0.0564 (9)
H8A	0.4878	−0.2153	0.4384	0.068*
C1	−0.3839 (4)	0.5235 (3)	0.7581 (3)	0.0659 (10)
H1B	−0.4453	0.5463	0.8492	0.099*
H1C	−0.4594	0.5117	0.7016	0.099*
H1D	−0.3215	0.6079	0.6984	0.099*
C9	0.3559 (4)	−0.0064 (3)	0.3426 (3)	0.0504 (8)
C11	0.4429 (5)	0.0117 (4)	0.1835 (4)	0.0734 (11)
H11A	0.3959	0.1073	0.1191	0.110*
H11B	0.4302	−0.0754	0.1526	0.110*
H11C	0.5587	0.0150	0.1761	0.110*
C2	−0.2675 (4)	0.3748 (3)	0.7971 (4)	0.0549 (9)
C13	0.8161 (5)	−0.3725 (4)	0.1088 (4)	0.0802 (12)
H13A	0.7230	−0.2939	0.1209	0.120*
H13B	0.7938	−0.4339	0.0519	0.120*
H13C	0.9131	−0.3229	0.0561	0.120*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N2	0.0466 (16)	0.0427 (13)	0.0422 (14)	0.0025 (11)	−0.0123 (12)	−0.0088 (10)
N3	0.0497 (17)	0.0534 (14)	0.0479 (15)	−0.0011 (13)	−0.0106 (13)	−0.0165 (11)
O3	0.0696 (17)	0.0648 (13)	0.0544 (14)	0.0067 (12)	−0.0116 (12)	−0.0051 (10)
C6	0.049 (2)	0.0403 (15)	0.0454 (17)	0.0008 (14)	−0.0183 (15)	−0.0089 (13)
C10	0.046 (2)	0.0418 (16)	0.0518 (19)	0.0017 (14)	−0.0195 (16)	−0.0124 (14)
C3	0.050 (2)	0.0474 (16)	0.0463 (18)	0.0025 (14)	−0.0161 (15)	−0.0150 (13)
C4	0.069 (2)	0.0499 (16)	0.0403 (16)	0.0040 (16)	−0.0168 (16)	−0.0073 (13)
O2	0.0814 (19)	0.0733 (15)	0.0530 (15)	0.0150 (13)	−0.0145 (14)	−0.0142 (12)
C5	0.063 (2)	0.0435 (16)	0.0499 (19)	0.0003 (15)	−0.0160 (17)	−0.0061 (13)
N1	0.0588 (19)	0.0493 (13)	0.0455 (14)	0.0120 (13)	−0.0159 (13)	−0.0103 (11)
O1	0.093 (2)	0.0765 (15)	0.0464 (14)	0.0227 (14)	−0.0069 (12)	−0.0092 (11)
C7	0.055 (2)	0.0464 (17)	0.063 (2)	0.0073 (15)	−0.0226 (17)	−0.0115 (14)
C12	0.061 (2)	0.0537 (18)	0.052 (2)	−0.0009 (17)	−0.0167 (18)	−0.0058 (15)
C8	0.054 (2)	0.0514 (17)	0.065 (2)	0.0060 (16)	−0.0167 (18)	−0.0213 (15)
C1	0.062 (2)	0.0562 (19)	0.063 (2)	0.0124 (17)	−0.0070 (18)	−0.0096 (16)
C9	0.047 (2)	0.0543 (18)	0.0519 (19)	−0.0030 (15)	−0.0084 (16)	−0.0209 (15)
C11	0.068 (3)	0.079 (2)	0.070 (2)	0.007 (2)	−0.007 (2)	−0.0303 (18)
C2	0.052 (2)	0.0570 (18)	0.0480 (19)	0.0035 (16)	−0.0085 (16)	−0.0122 (15)
C13	0.083 (3)	0.076 (2)	0.064 (2)	0.000 (2)	−0.024 (2)	0.0049 (18)

Geometric parameters (Å, º) top

N2—C3	1.315 (3)	O1—C2	1.211 (3)
N2—C10	1.365 (3)	C7—C8	1.344 (4)
N3—C9	1.322 (3)	C7—H7A	0.9300
N3—C10	1.353 (3)	C12—C13	1.497 (4)
O3—C12	1.310 (3)	C8—C9	1.413 (4)
O3—H3A	0.8200	C8—H8A	0.9300
C6—C5	1.399 (4)	C1—C2	1.498 (4)
C6—C7	1.402 (4)	C1—H1B	0.9600
C6—C10	1.414 (3)	C1—H1C	0.9600
C3—N1	1.397 (3)	C1—H1D	0.9600
C3—C4	1.426 (4)	C9—C11	1.489 (4)
C4—C5	1.364 (4)	C11—H11A	0.9600
C4—H4A	0.9300	C11—H11B	0.9600
O2—C12	1.195 (3)	C11—H11C	0.9600
C5—H5A	0.9300	C13—H13A	0.9600
N1—C2	1.371 (3)	C13—H13B	0.9600
N1—H1A	0.8600	C13—H13C	0.9600

C3—N2—C10	118.3 (2)	C7—C8—C9	119.2 (3)
C9—N3—C10	117.6 (2)	C7—C8—H8A	120.4
C12—O3—H3A	109.5	C9—C8—H8A	120.4
C5—C6—C7	125.0 (3)	C2—C1—H1B	109.5
C5—C6—C10	118.0 (2)	C2—C1—H1C	109.5
C7—C6—C10	117.0 (3)	H1B—C1—H1C	109.5
N3—C10—N2	115.3 (2)	C2—C1—H1D	109.5
N3—C10—C6	123.0 (2)	H1B—C1—H1D	109.5
N2—C10—C6	121.7 (3)	H1C—C1—H1D	109.5
N2—C3—N1	114.4 (2)	N3—C9—C8	123.1 (3)
N2—C3—C4	124.0 (2)	N3—C9—C11	116.5 (3)
N1—C3—C4	121.7 (3)	C8—C9—C11	120.4 (3)
C5—C4—C3	117.3 (3)	C9—C11—H11A	109.5
C5—C4—H4A	121.3	C9—C11—H11B	109.5
C3—C4—H4A	121.3	H11A—C11—H11B	109.5
C4—C5—C6	120.7 (3)	C9—C11—H11C	109.5
C4—C5—H5A	119.7	H11A—C11—H11C	109.5
C6—C5—H5A	119.7	H11B—C11—H11C	109.5
C2—N1—C3	129.4 (2)	O1—C2—N1	124.0 (3)
C2—N1—H1A	115.3	O1—C2—C1	122.8 (3)
C3—N1—H1A	115.3	N1—C2—C1	113.3 (3)
C8—C7—C6	120.1 (3)	C12—C13—H13A	109.5
C8—C7—H7A	120.0	C12—C13—H13B	109.5
C6—C7—H7A	120.0	H13A—C13—H13B	109.5
O2—C12—O3	123.8 (3)	C12—C13—H13C	109.5
O2—C12—C13	123.9 (3)	H13A—C13—H13C	109.5
O3—C12—C13	112.2 (3)	H13B—C13—H13C	109.5

C9—N3—C10—N2	−179.5 (3)	C7—C6—C5—C4	179.3 (3)
C9—N3—C10—C6	0.7 (4)	C10—C6—C5—C4	−1.1 (5)
C3—N2—C10—N3	−179.2 (3)	N2—C3—N1—C2	−170.8 (3)
C3—N2—C10—C6	0.6 (4)	C4—C3—N1—C2	10.3 (5)
C5—C6—C10—N3	−179.7 (3)	C5—C6—C7—C8	179.0 (3)
C7—C6—C10—N3	0.0 (4)	C10—C6—C7—C8	−0.6 (5)
C5—C6—C10—N2	0.6 (4)	C6—C7—C8—C9	0.6 (5)
C7—C6—C10—N2	−179.8 (3)	C10—N3—C9—C8	−0.7 (4)
C10—N2—C3—N1	179.9 (3)	C10—N3—C9—C11	179.8 (3)
C10—N2—C3—C4	−1.3 (5)	C7—C8—C9—N3	0.0 (5)
N2—C3—C4—C5	0.8 (5)	C7—C8—C9—C11	179.5 (3)
N1—C3—C4—C5	179.5 (3)	C3—N1—C2—O1	−2.5 (5)
C3—C4—C5—C6	0.5 (5)	C3—N1—C2—C1	177.9 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	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.

Experimental details

Crystal data
Chemical formula	C₁₁H₁₁N₃O·C₂H₄O₂
M_r	261.28
Crystal system, space group	Triclinic, 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)
V (Å³)	659.8 (2)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.15 × 0.10 × 0.07

Data collection
Diffractometer	Rigaku R-AXIS RAPID diffractometer
Absorption correction	Multi-scan (ABSCOR; Higashi, 1995)
T_min, T_max	0.986, 0.993
No. of measured, independent and observed [I > 2σ(I)] reflections	5757, 2591, 1014
R_int	0.058
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.047, 0.160, 0.91
No. of reflections	2591
No. of parameters	172
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	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···A	D—H	H···A	D···A	D—H···A
O3—H3A···N2ⁱ	0.82	1.96	2.774 (3)	173.1
N1—H1A···O2ⁱⁱ	0.86	2.07	2.931 (3)	178.2

Symmetry codes: (i) x+1, y−1, z; (ii) x−1, 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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