catena-Poly[[bis­(dimethyl­formamide-κO)cadmium(II)]-di-μ₂-dicyanamido-κ⁴N¹:N⁵]

In the title compound, [Cd(C₂N₃)₂(C₃H₇NO)₂], the Cd²⁺ ion lies on an inversion center and adopts an octa­hedral coordination geometry, in which four N atoms from four different dicyanamide ligands lie in the equatorial plane and two dimethyl­formamide O atoms occupy the axial positions. The Cd atoms are connected by two dicyanamide ligands, resulting in a neutral chain propagating parallel to [010].

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](N-C) = 0.004 Å
• R factor = 0.022
• wR factor = 0.058
• Data-to-parameter ratio = 14.5

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low .......       0.98
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for         N3
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        Cd1
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C1
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          3
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600         20
PLAT913_ALERT_3_C Missing # of Very Strong Reflections in FCF ....          2
PLAT048_ALERT_1_C MoietyFormula Not Given ........................          ?
PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L=  0.600          8

Alert level G
PLAT154_ALERT_1_G The su's on the Cell Angles are Equal  (x 10000)       3000 Deg.
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported   _diffrn_ambient_temperature        293 K
PLAT380_ALERT_4_G Check Incorrectly? Oriented X(sp2)-Methyl Moiety         C5

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   9 ALERT level C = Check and explain
   4 ALERT level G = General alerts; check

   4 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 ALERT type 2 Indicator that the structure model may be wrong or deficient
   4 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

The designed syntheses of metal-organic compounds have attracted great attention in recent years because of not only their intriguing variety of architectures and topologies (Eddaoudi et al., 2001; Zhang et al., 2008) but also their potential applications (Banerjee et al., 2008; Zhang et al., 2007). Dicyanamide acting as flexible bridging ligands can construct metal-organic compounds with various structures (Jensen et al., 1999; Zhang, 2009). The one-dimensional neutral compounds {Cd[N(CN)₂]₂(dmf)₂}_n are constructed by this bridging ligands through diffusion reactions. In this paper, the crystal structure of the title compound, (I), is presented.

As illustrated in Fig. 1, Cd²⁺ which lies on an inversion center, adopts an octahedral coordination geometry, where four N atoms from four different dicyanamide ligands lies in equatorial plane and two O atoms from dmf occupy the axial positions. Every two neighboring Cd atoms connected by two dicyanamide ligands, gives rise to a one-dimensional neutral chain.

Related literature

For architectures and topologies of metal-organic compounds, see: Eddaoudi et al. (2001); Zhang et al. (2008). For their potential applications, see: Banerjee et al. (2008); Zhang et al. (2007). For metal-organic compounds including dicyanamide ligands, see: Jensen et al. (1999); Zhang (2009).

S2. Experimental

Cd(NO₃)₂.4 H₂O (123.2 mg, 0.4 mmol) was added into 2 ml dmf with thorough stirring for 5 minutes. After filtration, the filtrate was carefully laid on the surface with the solution of NaN(CN)₂ (89.1 mg, 1 mmol) in 1 ml dmf and 6 ml CH₃CN. colorless block crystals were obtained after eight days. Yield: 199.3 mg in pure form, 51.0% based on Cd.

S3. Refinement

H atoms were positioned geometrically and refined with riding model, with U_iso = 1.5 and 1.2 U_eq for methyl and formyl H atoms, respectively. The C—H bonds are 0.96 Å in methyl and 0.93 Å in formyl.

Computing details

Data collection: CrystalClear (Rigaku, 2008); cell refinement: CrystalClear (Rigaku, 2008); data reduction: CrystalClear (Rigaku, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXT07 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures

Fig. 1. The molecular structure of the title compound, with atom labels and 30% probability displacement ellipsoids, all H atoms have been omitted (i -x + 1,-y + 1,-z; ii -x + 1,-y,-z).

catena-Poly[[bis(dimethylformamide-κO)cadmium(II)]- di-µ₂-dicyanamido-κ⁴N¹:N⁵]

Crystal data

[Cd(C2N3)2(C3H7NO)2]	Z = 1
Mr = 390.70	F(000) = 194
Triclinic, P1	Dx = 1.675 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 6.5325 (13) Å	Cell parameters from 1884 reflections
b = 7.6003 (15) Å	θ = 3.3–28.4°
c = 8.6051 (17) Å	µ = 1.43 mm^−1
α = 104.28 (3)°	T = 293 K
β = 106.90 (3)°	Block, colorless
γ = 97.05 (3)°	0.2 × 0.16 × 0.12 mm
V = 387.35 (17) Å^3

Data collection

Rigaku Saturn724+ diffractometer	1410 independent reflections
Radiation source: fine-focus sealed tube	1408 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.025
dtprofit.ref scans	θmax = 25.5°, θmin = 3.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −7→7
Tmin = 0.239, Tmax = 0.480	k = −7→9
3505 measured reflections	l = −9→10

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.022	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.058	H-atom parameters constrained
S = 1.10	w = 1/[σ^2(Fo^2) + (0.039P)^2 + 0.0503P] where P = (Fo^2 + 2Fc^2)/3
1410 reflections	(Δ/σ)max < 0.001
97 parameters	Δρmax = 0.44 e Å^−3
0 restraints	Δρmin = −0.36 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
Cd1	0.5000	0.5000	0.0000	0.04117 (11)
O1	0.7512 (3)	0.6362 (3)	0.2708 (2)	0.0572 (5)
N1	0.2979 (4)	0.3110 (3)	0.0987 (3)	0.0570 (6)
N2	0.2301 (6)	0.0218 (4)	0.1653 (4)	0.0781 (9)
N4	1.1012 (4)	0.7109 (3)	0.4447 (3)	0.0500 (5)
N3	0.6991 (4)	0.2758 (3)	−0.0440 (3)	0.0598 (6)
C1	0.2690 (4)	0.1705 (3)	0.1214 (3)	0.0449 (5)
C5	1.3277 (5)	0.6980 (6)	0.4658 (4)	0.0755 (9)
H5A	1.3381	0.6327	0.3586	0.113*
H5B	1.3766	0.6322	0.5470	0.113*
H5C	1.4177	0.8205	0.5059	0.113*
C4	1.0524 (7)	0.8062 (5)	0.5930 (4)	0.0728 (9)
H4A	0.8984	0.8039	0.5624	0.109*
H4B	1.1323	0.9326	0.6357	0.109*
H4C	1.0943	0.7454	0.6792	0.109*
C2	0.9476 (4)	0.6352 (4)	0.2975 (3)	0.0468 (6)
H2A	0.9885	0.5765	0.2063	0.056*
C3	0.7261 (4)	0.1317 (3)	−0.0954 (3)	0.0427 (5)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cd1	0.04194 (16)	0.03209 (15)	0.04955 (17)	0.01065 (10)	0.01353 (11)	0.01291 (10)
O1	0.0480 (11)	0.0673 (13)	0.0488 (9)	0.0118 (9)	0.0137 (8)	0.0076 (9)
N1	0.0607 (14)	0.0420 (12)	0.0744 (15)	0.0081 (10)	0.0296 (12)	0.0209 (11)
N2	0.136 (3)	0.0421 (13)	0.0862 (18)	0.0263 (15)	0.077 (2)	0.0210 (13)
N4	0.0533 (12)	0.0530 (12)	0.0389 (10)	0.0105 (10)	0.0105 (9)	0.0115 (9)
N3	0.0660 (15)	0.0466 (13)	0.0771 (15)	0.0271 (11)	0.0296 (12)	0.0221 (11)
C1	0.0469 (13)	0.0378 (13)	0.0505 (13)	0.0082 (10)	0.0217 (10)	0.0080 (10)
C5	0.0518 (17)	0.100 (3)	0.0616 (18)	0.0162 (17)	0.0065 (14)	0.0165 (17)
C4	0.093 (2)	0.076 (2)	0.0426 (14)	0.0225 (18)	0.0204 (15)	0.0069 (14)
C2	0.0495 (14)	0.0473 (14)	0.0397 (12)	0.0070 (11)	0.0134 (10)	0.0096 (10)
C3	0.0457 (13)	0.0391 (13)	0.0461 (12)	0.0110 (10)	0.0167 (10)	0.0150 (10)

Geometric parameters (Å, º)

Cd1—N3^i	2.291 (2)	N4—C4	1.446 (4)
Cd1—N3	2.291 (2)	N4—C5	1.456 (4)
Cd1—N1	2.306 (2)	N3—C3	1.132 (3)
Cd1—N1^i	2.306 (2)	C5—H5A	0.9600
Cd1—O1	2.316 (2)	C5—H5B	0.9600
Cd1—O1^i	2.316 (2)	C5—H5C	0.9600
O1—C2	1.237 (3)	C4—H4A	0.9600
N1—C1	1.136 (3)	C4—H4B	0.9600
N2—C3^ii	1.281 (4)	C4—H4C	0.9600
N2—C1	1.296 (4)	C2—H2A	0.9300
N4—C2	1.305 (3)	C3—N2^ii	1.281 (4)
N3^i—Cd1—N3	180.0	C4—N4—C5	117.7 (3)
N3^i—Cd1—N1	91.27 (9)	C3—N3—Cd1	156.3 (2)
N3—Cd1—N1	88.73 (9)	N1—C1—N2	172.2 (3)
N3^i—Cd1—N1^i	88.73 (9)	N4—C5—H5A	109.5
N3—Cd1—N1^i	91.27 (9)	N4—C5—H5B	109.5
N1—Cd1—N1^i	180.00 (11)	H5A—C5—H5B	109.5
N3^i—Cd1—O1	90.45 (9)	N4—C5—H5C	109.5
N3—Cd1—O1	89.55 (9)	H5A—C5—H5C	109.5
N1—Cd1—O1	91.26 (9)	H5B—C5—H5C	109.5
N1^i—Cd1—O1	88.74 (9)	N4—C4—H4A	109.5
N3^i—Cd1—O1^i	89.55 (9)	N4—C4—H4B	109.5
N3—Cd1—O1^i	90.45 (9)	H4A—C4—H4B	109.5
N1—Cd1—O1^i	88.74 (9)	N4—C4—H4C	109.5
N1^i—Cd1—O1^i	91.26 (9)	H4A—C4—H4C	109.5
O1—Cd1—O1^i	180.00 (11)	H4B—C4—H4C	109.5
C2—O1—Cd1	120.12 (16)	O1—C2—N4	124.5 (2)
C1—N1—Cd1	145.5 (2)	O1—C2—H2A	117.7
C3^ii—N2—C1	122.3 (2)	N4—C2—H2A	117.7
C2—N4—C4	121.4 (3)	N3—C3—N2^ii	172.2 (3)
C2—N4—C5	120.8 (2)

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