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Acta Cryst. (2008). E64, m54-m55    [ doi:10.1107/S160053680706271X ]

Bis(7-amino-2,4-dimethyl-1,8-naphthyridine)dinitratocadmium(II)

S.-W. Jin, Q.-J. Zhao, X.-G. Qian, R.-X. Chen and Y.-F. Shi

Abstract top

In the title compound, [Cd(NO3)2(C10H11N3)2], two naphthyridine ring systems are coordinated to the Cd ion through the two N atoms in a bidentate chelating mode, whereas the remaining coordination sites are occupied by two O atoms from two different nitrate groups to complete the octahedral geometry. Intermoleular N-H...O hydrogen bonds link the molecules to form a one-dimensionnal sheet parallel to the ac plane. Weak slipped [pi]-[pi] stacking involving the naphthyridine ring systems stabilizes the structure.

Comment top

Molecular structures and chemical properties of transition metal complexes of 1,8-naphthyridine (napy) and its derivatives have received much attention(Kukrek et al., 2006; Che et al., 2001), because the ligands can link to metals with several coordination modes such as monodentate, chelating bidentate, and dinuclear bridging binding fashion (Gavrilova & Bosnich, 2004). 5,7-dimethyl-1,8-naphthyridin-2-amine (L) is a potentially tridentate ligand and is capable of linking two to four metal atoms together to form metal aggregates (Oskui et al., 1999; Mintert & Sheldrick, 1995a; Oskui & Sheldrick, 1999; Mintert & Sheldrick, 1995b). The coordination chemistry of 5,7-dimethyl-1,8-naphthyridine-2-amine has not been well studied before although a series of transiton metal complex (M(L)2Cl2) were once described in a US patent (Bayer, 1979). As an extension of our study on naphthyridine coordination chemistry(Jin et al., 2007), herein the title complex [Cd(L)2(NO3)2] is reported.

In the title compound, two naphthyridine are coordinated to the Cd ion through two nitrogen atoms in bidentate chelating mode whereas the remaining coordination sites are occupied by two oxygen atoms from two different nitrates (Fig. 1). The two nitrate ligands display a dissymetric chelating mode with Cd—O distances of 2.357 (4) and 2.718 (4). The remaining distances are within the usual range. The two naphthyridine rings were almost perpendicular to each other making dihedral angle of 80.22 (7)°. The two chelating Cd—O—N—O group make dihedral angle of 81.21 (12)°.

Intermoleular N—H···O hydrogen bonds link the molecules to form a one dimensionnal sheet parallel to the a axis (Table 1, Fig. 2). Weak slippest π-π stackings involving the naphthyridine rings stabilize the structure (Table 2).

Related literature top

For related literature, see: Bayer (1979); Che et al. (2001); Gavrilova & Bosnich (2004); Jin et al. (2007); Kukrek et al. (2006); Mintert & Sheldrick (1995a,b); Oskui & Sheldrick (1999); Oskui, Mintert & Sheldrick (1999).

Experimental top

All reagents and solvents were used as obtained without further purification. The CHN elemental analyses were performed on a Perkin-Elmer model 2400 elemental analyzer. A solution of cadmium nitrate tetrahydrate (31.4 mg, 0.1 mmol) in methanol (3 ml) was added to L (52.2 mg, 0.3 mmol) in methanol (10 ml) to give a colorless solution. The methanol solution was filtered. The solution was left standing at room temperature for several days, colorless block crystals were isolated. Yield: 41 mg, 70.3%. Anal. Calcd. for C20H22CdN8O6: C, 41.18; H, 3.77; N, 19.22. Found: C, 41.14; H, 3.72; N, 19.18.

Refinement top

All H atoms attached to C atoms and N atom were fixed geometrically and treated as riding with C—H = 0.93 Å (aromatic) or 0.96 Å (methyl) and N—H = 0.86 Å with Uiso(H) = 1.2Ueq(Caromatic or N) or Uiso(H) = 1.5Ueq(Cmethyl).

Computing details top

Data collection: SMART (Bruker, 1999); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).

Figures top
[Figure 1] Fig. 1. Molecular view of the title compound, showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms have been omitted for clarity.
[Figure 2] Fig. 2. Partial packing view showing the N—H···O hydrogen bonds. Hydrogen bonds are shown as dashed lines. H atoms not involved in hydrogen bondings have been omitted for clarity.
Dinitratobis(7-amino-2,4-dimethyl-1,8-naphthyridine)cadmium(II) top
Crystal data top
[Cd(NO3)2(C10H11N3)2]Z = 2
Mr = 582.86F000 = 588
Triclinic, P1Dx = 1.641 Mg m−3
Hall symbol: -P 1Mo Kα radiation
λ = 0.71073 Å
a = 9.308 (2) ÅCell parameters from 2793 reflections
b = 9.584 (2) Åθ = 2.4–26.1º
c = 15.067 (4) ŵ = 0.98 mm−1
α = 95.497 (3)ºT = 298 (2) K
β = 95.224 (3)ºBlock, colorless
γ = 116.865 (3)º0.45 × 0.37 × 0.31 mm
V = 1179.8 (5) Å3
Data collection top
Bruker SMART
diffractometer		4101 independent reflections
Radiation source: fine-focus sealed tube3346 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.019
T = 298(2) Kθmax = 25.0º
φ and ω scansθmin = 2.4º
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −11→6
Tmin = 0.667, Tmax = 0.751k = −11→11
6136 measured reflectionsl = −17→17
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.035H-atom parameters constrained
wR(F2) = 0.081  w = 1/[σ2(Fo2) + (0.037P)2 + 0.1524P]
where P = (Fo2 + 2Fc2)/3
S = 1.09(Δ/σ)max = 0.004
4101 reflectionsΔρmax = 0.67 e Å−3
320 parametersΔρmin = −0.36 e Å−3
Primary atom site location: structure-invariant direct methodsExtinction correction: none
Crystal data top
[Cd(NO3)2(C10H11N3)2]γ = 116.865 (3)º
Mr = 582.86V = 1179.8 (5) Å3
Triclinic, P1Z = 2
a = 9.308 (2) ÅMo Kα
b = 9.584 (2) ŵ = 0.98 mm−1
c = 15.067 (4) ÅT = 298 (2) K
α = 95.497 (3)º0.45 × 0.37 × 0.31 mm
β = 95.224 (3)º
Data collection top
Bruker SMART
diffractometer		4101 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		3346 reflections with I > 2σ(I)
Tmin = 0.667, Tmax = 0.751Rint = 0.019
6136 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.035320 parameters
wR(F2) = 0.081H-atom parameters constrained
S = 1.09Δρmax = 0.67 e Å−3
4101 reflectionsΔρmin = −0.36 e Å−3
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
Cd10.32533 (3)0.63678 (3)0.248895 (17)0.04168 (11)
N10.3847 (3)0.7270 (3)0.41178 (18)0.0381 (7)
N20.5294 (3)0.6210 (3)0.34613 (18)0.0385 (7)
N30.6662 (4)0.5103 (4)0.2720 (2)0.0624 (10)
H3A0.60260.49430.22280.075*
H3B0.74180.48200.27190.075*
N40.5509 (4)0.8962 (4)0.2110 (2)0.0448 (7)
N50.2822 (4)0.8123 (3)0.17237 (18)0.0407 (7)
N60.0057 (4)0.7107 (4)0.1316 (2)0.0616 (9)
H6A−0.00970.63480.16190.074*
H6B−0.07630.71520.10340.074*
N70.2627 (5)0.4197 (4)0.0808 (2)0.0568 (9)
N80.0220 (4)0.4282 (4)0.3115 (2)0.0459 (8)
O10.1458 (4)0.4451 (4)0.0924 (2)0.0826 (10)
O20.3852 (4)0.4845 (4)0.1406 (2)0.0784 (10)
O30.2607 (4)0.3373 (4)0.0126 (2)0.0803 (10)
O40.1344 (3)0.3951 (3)0.29808 (18)0.0550 (7)
O50.0207 (4)0.5429 (4)0.27969 (18)0.0622 (8)
O6−0.0832 (5)0.3513 (4)0.3543 (2)0.0927 (11)
C10.5092 (4)0.6900 (4)0.4236 (2)0.0342 (8)
C20.6476 (4)0.5792 (4)0.3489 (2)0.0395 (8)
C30.7515 (4)0.6041 (4)0.4305 (2)0.0447 (9)
H30.83230.57220.43110.054*
C40.7316 (4)0.6744 (4)0.5071 (2)0.0427 (9)
H40.80130.69390.56030.051*
C50.6056 (4)0.7189 (4)0.5074 (2)0.0361 (8)
C60.5702 (4)0.7900 (4)0.5826 (2)0.0403 (8)
C70.4400 (5)0.8216 (4)0.5692 (2)0.0449 (9)
H70.41160.86520.61810.054*
C80.3495 (4)0.7898 (4)0.4836 (2)0.0386 (8)
C90.6701 (5)0.8290 (5)0.6740 (2)0.0586 (11)
H9A0.62250.86770.71770.088*
H9B0.77910.90880.67240.088*
H9C0.67250.73560.69020.088*
C100.2099 (5)0.8259 (5)0.4700 (3)0.0533 (10)
H10A0.18510.82940.40730.080*
H10B0.23830.92660.50470.080*
H10C0.11650.74510.48930.080*
C110.4365 (5)0.9236 (4)0.1670 (2)0.0406 (8)
C120.1564 (5)0.8210 (5)0.1283 (2)0.0470 (9)
C130.1818 (6)0.9478 (5)0.0788 (3)0.0560 (11)
H130.09280.95390.04960.067*
C140.3334 (6)1.0585 (5)0.0741 (3)0.0571 (11)
H140.34891.14100.04190.069*
C150.4704 (5)1.0502 (4)0.1182 (2)0.0466 (9)
C160.6348 (6)1.1545 (5)0.1155 (3)0.0545 (11)
C170.7501 (6)1.1242 (5)0.1602 (3)0.0623 (12)
H170.85981.19080.15920.075*
C180.7068 (5)0.9956 (5)0.2072 (3)0.0554 (10)
C190.6828 (6)1.2936 (5)0.0644 (3)0.0732 (14)
H19A0.79921.34790.06800.110*
H19B0.64611.36480.09040.110*
H19C0.63361.25610.00230.110*
C200.8329 (5)0.9635 (6)0.2569 (4)0.0837 (15)
H20A0.81940.96300.31930.126*
H20B0.93961.04460.25210.126*
H20C0.82060.86240.23130.126*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cd10.03665 (17)0.05040 (19)0.03889 (17)0.02133 (13)−0.00124 (11)0.01172 (12)
N10.0334 (16)0.0441 (18)0.0397 (17)0.0198 (15)0.0055 (13)0.0101 (14)
N20.0343 (16)0.0515 (19)0.0318 (16)0.0219 (15)0.0033 (13)0.0070 (13)
N30.056 (2)0.103 (3)0.0426 (19)0.053 (2)0.0011 (16)−0.0061 (19)
N40.0439 (19)0.0461 (19)0.0428 (18)0.0198 (17)0.0060 (15)0.0060 (14)
N50.0465 (19)0.0442 (18)0.0313 (16)0.0218 (16)0.0004 (14)0.0064 (13)
N60.047 (2)0.072 (3)0.064 (2)0.026 (2)−0.0057 (17)0.0254 (19)
N70.076 (3)0.057 (2)0.041 (2)0.037 (2)−0.0073 (19)0.0058 (17)
N80.0391 (18)0.054 (2)0.0418 (18)0.0183 (17)0.0073 (15)0.0091 (16)
O10.083 (2)0.101 (3)0.081 (2)0.061 (2)0.0066 (19)0.0053 (19)
O20.073 (2)0.100 (3)0.0541 (19)0.044 (2)−0.0205 (16)−0.0151 (17)
O30.111 (3)0.096 (3)0.0524 (19)0.077 (2)−0.0252 (18)−0.0190 (17)
O40.0460 (16)0.0676 (19)0.0608 (18)0.0351 (15)0.0044 (13)0.0099 (14)
O50.072 (2)0.071 (2)0.0607 (18)0.0446 (18)0.0102 (15)0.0249 (16)
O60.089 (3)0.092 (3)0.100 (3)0.032 (2)0.060 (2)0.037 (2)
C10.0311 (18)0.0372 (19)0.0331 (19)0.0152 (16)0.0029 (15)0.0069 (15)
C20.033 (2)0.048 (2)0.039 (2)0.0206 (18)0.0045 (16)0.0052 (17)
C30.034 (2)0.055 (2)0.049 (2)0.0253 (19)−0.0001 (17)0.0072 (19)
C40.035 (2)0.050 (2)0.039 (2)0.0176 (18)−0.0038 (16)0.0045 (17)
C50.0343 (19)0.0355 (19)0.0347 (19)0.0139 (17)0.0013 (15)0.0042 (15)
C60.041 (2)0.039 (2)0.037 (2)0.0156 (18)0.0013 (16)0.0029 (16)
C70.048 (2)0.042 (2)0.043 (2)0.0206 (19)0.0096 (18)0.0027 (17)
C80.0327 (19)0.034 (2)0.048 (2)0.0130 (16)0.0113 (17)0.0103 (17)
C90.062 (3)0.076 (3)0.037 (2)0.036 (2)−0.0058 (19)−0.006 (2)
C100.046 (2)0.059 (3)0.067 (3)0.032 (2)0.014 (2)0.014 (2)
C110.050 (2)0.037 (2)0.0300 (19)0.0172 (19)0.0063 (17)−0.0007 (15)
C120.057 (3)0.052 (2)0.035 (2)0.029 (2)0.0013 (18)0.0076 (18)
C130.069 (3)0.062 (3)0.046 (2)0.038 (3)0.003 (2)0.015 (2)
C140.090 (4)0.051 (3)0.041 (2)0.040 (3)0.013 (2)0.0157 (19)
C150.067 (3)0.038 (2)0.034 (2)0.023 (2)0.0129 (19)0.0019 (17)
C160.075 (3)0.040 (2)0.036 (2)0.016 (2)0.014 (2)−0.0011 (18)
C170.059 (3)0.053 (3)0.060 (3)0.013 (2)0.018 (2)0.002 (2)
C180.044 (2)0.056 (3)0.059 (3)0.019 (2)0.007 (2)0.000 (2)
C190.097 (4)0.043 (3)0.057 (3)0.011 (3)0.028 (3)0.009 (2)
C200.047 (3)0.082 (4)0.118 (4)0.027 (3)0.008 (3)0.020 (3)
Geometric parameters (Å, °) top
Cd1—N52.284 (3)C4—H40.9300
Cd1—O22.355 (3)C5—C61.408 (5)
Cd1—N22.361 (3)C6—C71.379 (5)
Cd1—O42.433 (3)C6—C91.501 (5)
Cd1—N12.448 (3)C7—C81.400 (5)
Cd1—N42.586 (3)C7—H70.9300
N1—C81.326 (4)C8—C101.490 (5)
N1—C11.359 (4)C9—H9A0.9600
N2—C21.328 (4)C9—H9B0.9600
N2—C11.356 (4)C9—H9C0.9600
N3—C21.343 (4)C10—H10A0.9600
N3—H3A0.8600C10—H10B0.9600
N3—H3B0.8600C10—H10C0.9600
N4—C181.339 (5)C11—C151.406 (5)
N4—C111.342 (5)C12—C131.427 (5)
N5—C121.333 (4)C13—C141.342 (6)
N5—C111.364 (5)C13—H130.9300
N6—C121.330 (5)C14—C151.422 (6)
N6—H6A0.8600C14—H140.9300
N6—H6B0.8600C15—C161.406 (6)
N7—O31.229 (4)C16—C171.370 (6)
N7—O11.241 (4)C16—C191.514 (5)
N7—O21.250 (4)C17—C181.398 (6)
N8—O61.213 (4)C17—H170.9300
N8—O51.246 (4)C18—C201.498 (6)
N8—O41.250 (4)C19—H19A0.9600
C1—C51.405 (4)C19—H19B0.9600
C2—C31.423 (5)C19—H19C0.9600
C3—C41.351 (5)C20—H20A0.9600
C3—H30.9300C20—H20B0.9600
C4—C51.418 (5)C20—H20C0.9600
N5—Cd1—O2104.91 (11)C7—C6—C9121.4 (3)
N5—Cd1—N2140.76 (11)C5—C6—C9121.2 (3)
O2—Cd1—N284.14 (10)C6—C7—C8121.6 (3)
N5—Cd1—O4130.94 (10)C6—C7—H7119.2
O2—Cd1—O489.68 (11)C8—C7—H7119.2
N2—Cd1—O486.30 (9)N1—C8—C7121.4 (3)
N5—Cd1—N1111.10 (9)N1—C8—C10117.6 (3)
O2—Cd1—N1139.39 (10)C7—C8—C10121.0 (3)
N2—Cd1—N156.05 (9)C6—C9—H9A109.5
O4—Cd1—N180.82 (9)C6—C9—H9B109.5
N5—Cd1—N454.63 (10)H9A—C9—H9B109.5
O2—Cd1—N491.13 (11)C6—C9—H9C109.5
N2—Cd1—N487.67 (10)H9A—C9—H9C109.5
O4—Cd1—N4173.80 (9)H9B—C9—H9C109.5
N1—Cd1—N494.61 (9)C8—C10—H10A109.5
C8—N1—C1118.2 (3)C8—C10—H10B109.5
C8—N1—Cd1148.2 (2)H10A—C10—H10B109.5
C1—N1—Cd193.59 (19)C8—C10—H10C109.5
C2—N2—C1118.5 (3)H10A—C10—H10C109.5
C2—N2—Cd1143.8 (2)H10B—C10—H10C109.5
C1—N2—Cd197.6 (2)N4—C11—N5112.6 (3)
C2—N3—H3A120.0N4—C11—C15124.2 (4)
C2—N3—H3B120.0N5—C11—C15123.2 (3)
H3A—N3—H3B120.0N6—C12—N5119.3 (3)
C18—N4—C11117.4 (3)N6—C12—C13120.0 (4)
C18—N4—Cd1152.3 (3)N5—C12—C13120.7 (4)
C11—N4—Cd189.8 (2)C14—C13—C12120.4 (4)
C12—N5—C11119.0 (3)C14—C13—H13119.8
C12—N5—Cd1137.6 (3)C12—C13—H13119.8
C11—N5—Cd1102.9 (2)C13—C14—C15120.3 (4)
C12—N6—H6A120.0C13—C14—H14119.8
C12—N6—H6B120.0C15—C14—H14119.8
H6A—N6—H6B120.0C11—C15—C16117.8 (4)
O3—N7—O1121.8 (4)C11—C15—C14116.3 (4)
O3—N7—O2120.9 (4)C16—C15—C14125.9 (4)
O1—N7—O2117.3 (3)C17—C16—C15117.4 (4)
O6—N8—O5120.6 (3)C17—C16—C19121.2 (4)
O6—N8—O4121.3 (4)C15—C16—C19121.5 (4)
O5—N8—O4118.1 (3)C16—C17—C18121.5 (4)
N7—O2—Cd1105.8 (3)C16—C17—H17119.2
N8—O4—Cd1100.6 (2)C18—C17—H17119.2
N2—C1—N1112.7 (3)N4—C18—C17121.8 (4)
N2—C1—C5123.7 (3)N4—C18—C20116.7 (4)
N1—C1—C5123.5 (3)C17—C18—C20121.6 (4)
N2—C2—N3118.1 (3)C16—C19—H19A109.5
N2—C2—C3121.8 (3)C16—C19—H19B109.5
N3—C2—C3120.1 (3)H19A—C19—H19B109.5
C4—C3—C2119.3 (3)C16—C19—H19C109.5
C4—C3—H3120.4H19A—C19—H19C109.5
C2—C3—H3120.4H19B—C19—H19C109.5
C3—C4—C5120.7 (3)C18—C20—H20A109.5
C3—C4—H4119.7C18—C20—H20B109.5
C5—C4—H4119.7H20A—C20—H20B109.5
C1—C5—C6117.8 (3)C18—C20—H20C109.5
C1—C5—C4116.0 (3)H20A—C20—H20C109.5
C6—C5—C4126.2 (3)H20B—C20—H20C109.5
C7—C6—C5117.4 (3)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N3—H3A···O20.862.233.033 (4)155
N3—H3B···O5i0.862.383.161 (4)151
N6—H6A···O50.862.112.902 (4)153
N6—H6B···O3ii0.862.182.979 (4)154
Symmetry codes: (i) x+1, y, z; (ii) −x, −y+1, −z.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N3—H3A···O20.862.233.033 (4)155
N3—H3B···O5i0.862.383.161 (4)151
N6—H6A···O50.862.112.902 (4)153
N6—H6B···O3ii0.862.182.979 (4)154
Symmetry codes: (i) x+1, y, z; (ii) −x, −y+1, −z.
Table 2
Main π–π interactions (Å, °) in (I).
α is the dihedral angle between the planes, DCC is the length of the CC vector (centroid to centroid),
τ is the angle(s) subtended by the plane normal(s) to CC (offset angle).
Cg1 is the centroid of ring N1/C1/C5–C8,
Cg2 is the centroid of ring N2/C1/C5–C2.
Symmetry code: (iii) -x+1, -y+1, -z+1. top
Centroid 1Centroid 2αDCCτ
Cg1Cg2iii1.323.862 (2)26.0
Cg2Cg2iii0.03.823 (2)24.5
Acknowledgements top

The authors thank the Zhejiang Forestry University Science Foundation for financial support.

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