Synthesis, crystal structure and study of the crystal packing in the complex bis­(4-amino­pyridine-κN¹)di­chlorido­cobalt(II)

Despite the large number of reported crystalline structures of coordination complexes bearing pyridines as ligands, the relevance of π–π inter­actions among these hereroaromatic systems in the stabilization of their supra­molecular structures and properties is not very well documented in the recent literature. The title compound, [CoCl₂(C₅H₆N₂)₂], was obtained as bright-blue crystals suitable for single-crystal X-ray diffraction analysis from the reaction of 4-amino­pyridine with cobalt(II) chloride in ethanol. The new complex was fully characterized by a variety of spectroscopic techniques and single-crystal X-ray diffraction. The crystal structure showed a tetra­hedral complex stabilized mainly by bidimensional motifs constructed by π–π inter­actions with large horizontal displacements between the 4-amino­pyridine units, and N—H...Cl hydrogen bonds. Other short contacts, such as C—H...Cl inter­actions, complete the three-dimensional arrangement. The supra­molecular investigation was extended by statistical studies using the Cambridge Structural Database and a Hirshfeld surface analysis.

Computing details

Data collection: CrysAlis PRO (Agilent, 2013); cell refinement: CrysAlis PRO (Agilent, 2013); data reduction: CrysAlis PRO (Agilent, 2013); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009) and PLATON (Spek, 2009).

Bis(4-aminopyridine-κN¹)dichloridocobalt(II)

Crystal data

[CoCl2(C5H6N2)2]	F(000) = 638
Mr = 316.98	Dx = 1.603 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 8.9262 (9) Å	Cell parameters from 655 reflections
b = 9.9679 (10) Å	θ = 4.3–23.4°
c = 14.9683 (13) Å	µ = 1.66 mm^−1
β = 101.825 (10)°	T = 293 K
V = 1303.6 (2) Å^3	Prism, blue
Z = 4	0.63 × 0.12 × 0.05 mm

Data collection

Xcalibur, Eos, Gemini diffractometer	1515 independent reflections
Radiation source: Enhance (Mo) X-ray Source	790 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.099
Detector resolution: 16.1158 pixels mm^-1	θmax = 28.8°, θmin = 3.8°
ω scans	h = −11→12
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2013)	k = −11→12
Tmin = 0.349, Tmax = 1.000	l = −19→20
4351 measured reflections

Refinement

Refinement on F^2	0 restraints
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.062	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.143	w = 1/[σ^2(Fo^2) + (0.0291P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.01	(Δ/σ)max < 0.001
1515 reflections	Δρmax = 0.48 e Å^−3
81 parameters	Δρmin = −0.37 e Å^−3

Special details

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq	Occ. (<1)
Co1	0.5000	0.57032 (10)	0.7500	0.0445 (4)	0.973 (5)
Cl1	0.28833 (18)	0.43946 (15)	0.71750 (9)	0.0653 (7)	0.977 (6)
N1	0.5120 (5)	0.6761 (4)	0.6377 (3)	0.0492 (12)
N2	0.4901 (7)	0.8335 (4)	0.3784 (3)	0.0805 (18)
H2A	0.5401	0.7964	0.3416	0.097*
H2B	0.4343	0.9029	0.3612	0.097*
C5	0.4266 (6)	0.7858 (5)	0.6082 (4)	0.0510 (14)
H5	0.3705	0.8250	0.6473	0.061*
C1	0.5911 (7)	0.6233 (5)	0.5793 (4)	0.0603 (17)
H1	0.6527	0.5492	0.5983	0.072*
C2	0.5866 (8)	0.6718 (6)	0.4937 (4)	0.0663 (18)
H2	0.6430	0.6298	0.4559	0.080*
C3	0.4990 (7)	0.7829 (5)	0.4627 (3)	0.0559 (15)
C4	0.4186 (6)	0.8418 (5)	0.5245 (3)	0.0537 (15)
H4	0.3604	0.9187	0.5081	0.064*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Co1	0.0407 (7)	0.0566 (8)	0.0380 (6)	0.000	0.0122 (4)	0.000
Cl1	0.0595 (11)	0.0848 (12)	0.0534 (9)	−0.0247 (9)	0.0156 (7)	−0.0028 (7)
N1	0.053 (3)	0.051 (3)	0.048 (2)	−0.009 (2)	0.021 (2)	−0.007 (2)
N2	0.127 (5)	0.067 (3)	0.047 (3)	0.005 (3)	0.019 (3)	0.009 (2)
C5	0.043 (3)	0.055 (3)	0.059 (3)	−0.005 (3)	0.021 (3)	−0.007 (3)
C1	0.074 (4)	0.055 (4)	0.060 (3)	0.007 (3)	0.034 (3)	0.005 (3)
C2	0.093 (5)	0.055 (4)	0.061 (4)	0.000 (3)	0.041 (4)	−0.006 (3)
C3	0.070 (4)	0.055 (3)	0.045 (3)	−0.018 (3)	0.017 (3)	−0.002 (3)
C4	0.052 (4)	0.054 (3)	0.054 (3)	0.001 (3)	0.007 (3)	0.005 (3)

Geometric parameters (Å, º)

Co1—Cl1^i	2.2652 (15)	C5—H5	0.9300
Co1—Cl1	2.2653 (15)	C5—C4	1.360 (7)
Co1—N1	2.006 (4)	C1—H1	0.9300
Co1—N1^i	2.006 (4)	C1—C2	1.363 (7)
N1—C5	1.354 (6)	C2—H2	0.9300
N1—C1	1.339 (6)	C2—C3	1.380 (7)
N2—H2A	0.8600	C3—C4	1.410 (7)
N2—H2B	0.8600	C4—H4	0.9300
N2—C3	1.346 (6)
Cl1^i—Co1—Cl1	109.68 (9)	C4—C5—H5	118.3
N1—Co1—Cl1^i	107.29 (13)	N1—C1—H1	118.1
N1—Co1—Cl1	107.96 (13)	N1—C1—C2	123.8 (5)
N1^i—Co1—Cl1^i	107.96 (13)	C2—C1—H1	118.1
N1^i—Co1—Cl1	107.29 (14)	C1—C2—H2	119.8
N1—Co1—N1^i	116.6 (2)	C1—C2—C3	120.4 (5)
C5—N1—Co1	125.1 (3)	C3—C2—H2	119.8
C1—N1—Co1	117.8 (4)	N2—C3—C2	122.4 (5)
C1—N1—C5	116.2 (4)	N2—C3—C4	121.3 (6)
H2A—N2—H2B	120.0	C2—C3—C4	116.3 (5)
C3—N2—H2A	120.0	C5—C4—C3	119.8 (5)
C3—N2—H2B	120.0	C5—C4—H4	120.1
N1—C5—H5	118.3	C3—C4—H4	120.1
N1—C5—C4	123.4 (5)
Co1—N1—C5—C4	−168.6 (4)	C5—N1—C1—C2	−1.5 (9)
Co1—N1—C1—C2	168.0 (5)	C1—N1—C5—C4	0.1 (8)
N1—C5—C4—C3	1.7 (8)	C1—C2—C3—N2	−179.4 (5)
N1—C1—C2—C3	1.0 (10)	C1—C2—C3—C4	0.9 (9)
N2—C3—C4—C5	178.1 (5)	C2—C3—C4—C5	−2.1 (8)

Symmetry code: (i) −x+1, y, −z+3/2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5···Cl1^ii	0.93 (1)	2.93 (1)	3.644 (6)	176 (1)
C2—H2···Cl1^iii	0.93 (1)	2.87 (1)	3.727 (6)	154 (1)
N2—H2b···Cl1^iv	0.86 (1)	2.62 (1)	3.447 (6)	163 (1)

Symmetry codes: (ii) −x+1/2, y+1/2, −z+3/2; (iii) −x+1, −y+1, −z+1; (iv) −x+1/2, −y+3/2, −z+1.