Synthesis, crystal structure and Hirshfeld surface analysis of tetra-aqua-bis-(isonicotinamide-κN1)cobalt(II) succinate.

The reaction of CoCl2 with succinic acid and isonicotinamide in basic solution produces the title complex [Co(C6H6N2O)2(H2O)4](C4H4O4). The cobalt(II) ion of the complex cation and the succinate anion are each located on an inversion centre. The CoII ion is octa-hedrally coordinated by four O atoms of water mol-ecules and two N atoms of isonicotinamide mol-ecules. The two ions are linked via Owater-H⋯Osuccinate hydrogen bonds, forming chains propagating along [001]. In the crystal, these hydrogen-bonded chains are linked into a three-dimensional framework by further O-H⋯O hydrogen bonds and N-H⋯O hydrogen bonds. The framework is reinforced by C-H⋯O hydrogen bonds. Hirshfeld surface analysis and two-dimensional fingerprint plots have been used to analyse the inter-molecular inter-actions present in the crystal.

Chemical context

Metal carboxyl­ates have attracted intense attention because of their inter­esting framework topologies. Among metal carboxyl­ates, succinate dianions (succ) have good conformational freedom and they possess some desirable features such as being a versatile ligand because of the four electron-donor oxygen atoms they carry, and their ability to link inorganic moieties. Metal succinates are one of the best di­carboxyl­ate-based moieties that display an inter­esting structural variety. Di­carb­oxy­lic acids such as succinic acid and amides have been particularly useful in creating many supra­molecular structures between isonicotinamide and a variety of carb­oxy­lic acid mol­ecules (Vishweshwar et al., 2003 ▸; Aakeröy et al., 2002 ▸). Di­carb­oxy­lic acid ligands have been utilized frequently in the synthesis of various metal carboxyl­ates. For this reason they have been investigated widely, both experimentally and computationally. We describe herein the synthesis, structural features and Hirshfeld surface analysis of a new tetra­aqua­bis­(isonicotinamide-κN)cobalt(II) succinate complex.

Structural commentary

The mol­ecular structure of the title complex is illustrated in Fig. 1 ▸. The cobalt(II) ion is coordinated octa­hedrally by four O atoms of water mol­ecules and two Npyridine atoms of isonicotinamide mol­ecules. The values of the Co—Owater and Co—Npyridine bond lengths and the bond angles involving atom Co1 (Table 1 ▸) are close to those reported for similar cobalt(II) complexes (Gao et al., 2006 ▸; Liu et al., 2012 ▸). The C—O bond lengths in the deprotonated carb­oxy­lic groups of the succinate dianion are almost the same, viz. 1.247 (3) Å for C7—O1 and 1.257 (3) Å for C7—O2, indicating delocalization of charge. Each O atom of the succinate dianion is linked to an H atom of a water mol­ecule via O—H⋯O hydrogen bonds, so forming chains along the c-axis direction (Table 2 ▸ and Figs. 1 ▸ and 2 ▸).

Figure 1

The mol­ecular structure of the title complex, with the atom labelling. Displacement ellipsoids are drawn at the 30% probability level. [Symmetry codes: (v) −x + 1, −y + 1, −z + 2; (vi) −x + 1, −y + 1, − z + 1.]

Table 1

Selected geometric parameters (Å, °)

Co1—O3	2.1134 (15)	Co1—N2	2.1540 (16)
Co1—O4	2.0795 (16)
O4—Co1—N2i	92.15 (7)	O3—Co1—N2i	88.85 (6)
O4—Co1—N2	87.85 (6)	O4i—Co1—O3	88.82 (7)
O3—Co1—N2	91.15 (6)	O4—Co1—O3	91.18 (7)

Symmetry code: (i) .

Table 2

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3B⋯O1	0.79 (4)	1.97 (4)	2.756 (3)	176 (3)
O4—H4A⋯O2	0.77 (3)	1.88 (3)	2.651 (2)	174 (3)
O3—H3A⋯O2ii	0.81 (3)	1.92 (3)	2.729 (2)	175 (3)
O4—H4B⋯O5iii	0.83 (4)	1.97 (4)	2.801 (2)	174 (3)
N1—H1A⋯O5iv	0.92 (4)	2.34 (4)	3.227 (3)	160 (3)
N1—H1B⋯O1v	0.87 (4)	2.14 (4)	2.966 (3)	160 (3)
C5—H5⋯O2ii	0.93	2.41	3.307 (3)	161
C6—H6⋯O5iv	0.93	2.31	3.223 (3)	167

Symmetry codes: (ii) ; (iii) ; (iv) ; (v) .

Figure 2

A view along the b axis of the crystal packing of the title complex. Dashed lines indicate the hydrogen bonds (see Table 2 ▸).

Supra­molecular features

In the crystal, the chains formed by O—H⋯O hydrogen bonds involving the succinate anions and the complex cations are linked by further O—H⋯O and N—H⋯O hydrogen bonds, forming a three-dimensional supra­molecular architecture (Table 2 ▸ and Fig. 2 ▸). Within the framework, C—H⋯O hydrogen bonds are also present (Table 2 ▸).

Hirshfeld surface analysis

CrystalExplorer17.5 (Turner et al., 2017 ▸) was used to analyse the inter­actions in the crystal. The mol­ecular Hirshfeld surfaces were obtained using a standard (high) surface resolution with the three-dimensional d norm surfaces mapped over a fixed colour scale of −0.728 (red) to 1.428 (blue). The red spots in the d norm surface (Fig. 3 ▸), indicate the regions of donor–acceptor inter­actions given in Table 2 ▸.

Figure 3

d norm mapped on the Hirshfeld surfaces to visualize the intra­molecular and inter­molecular inter­actions of the title complex.

The view of the three-dimensional Hirshfeld surface of the title compound plotted over electrostatic potential energy in the range −0.366 to 0.236 a.u. using the STO-3G basis set at the Hartree–Fock level of theory is given in Fig. 4 ▸. The C—H⋯O, N—H⋯O and O—H⋯O hydrogen-bond donors and acceptors are shown as blue and red areas around the related atoms with positive (hydrogen-bond donors) and negative (hydrogen-bond acceptors) electrostatic potentials, respectively.

Figure 4

A view of the three-dimensional Hirshfeld surface of the title complex, plotted over the electrostatic potential energy.

The fingerprint plot for the title complex is presented in Fig. 5 ▸. The contribution from the O⋯H/H⋯O contacts, corresponding to C—H⋯O, N—H⋯O and O—H⋯O inter­actions, is represented by a pair of sharp spikes characteristic of a strong hydrogen-bonding inter­action (43%) (Fig. 6 ▸ a). The H⋯H inter­actions appear in the middle of the scattered points in the two-dimensional fingerprint plots with an overall Hirshfeld surface of 39.8% (Fig. 6 ▸ b). The contribution of the other inter­molecular contacts to the Hirshfeld surfaces is C⋯H/H⋯C (8.4%) (Fig. 6 ▸ c). The C⋯C/C⋯C contacts with 3.8% contribution appear as points of low density (Fig. 6 ▸ d).

Figure 5

The fingerprint plot of the title compound.

Figure 6

(a) H⋯O/O⋯H, (b) H⋯H/H⋯H, (c) H⋯C/C⋯H and (d) C⋯C/C⋯C contacts in the title complex, showing the percentages of contacts contributing to the total Hirshfeld surface area.

Database survey

A search of the Cambridge Structural Database (CSD, version 5.39, update May 2018; Groom et al., 2016 ▸) revealed the structures of five similar tetra­aqua­bis­(isonicotinamide-κN 1)cobalt(II) complexes with different counter-anions. They include p-formyl­benzoate dihydrate (HUCPIF; Hökelek et al., 2009 ▸), bis­(3-hy­droxy­benzoate) tetra­hydrate (LAMMOD; Zaman et al., 2012 ▸), disaccharinate sesquihydrate (LEHHUC; Uçar et al., 2006 ▸), bis­(thio­phene-2,5-di­carboxyl­ate) dihydrate (NETQOU; Liu et al., 2012 ▸) and terephthalate dihydrate (SETHIJ; Gao et al., 2006 ▸). In all five complexes the cation possesses inversion symmetry with the cobalt ion being located on a centre of symmetry. The Co—Owater bond lengths vary from ca 2.057 to 2.115 Å, while the Co—Npyridine bond lengths vary from ca 2.131 to 2.169 Å. In the title complex, the cation also possesses inversion symmetry and the Co—Owater bond lengths [2.079 (2) and 2.113 (2) Å] and the Co—Npyridine bond length [2.154 (2) Å] fall within these limits. In addition, there are several precedents for succinic acid and isonicotin­amides, including the structures of bis­(isonico­tin­amide) succinic acid (Aakeröy et al., 2002 ▸), succinic acid N,N′-octane-1,8-diyldiisonicotinamide (Aakeröy et al., 2014 ▸), succinic acid bis­(isonicotinamide) (Vishweshwar et al., 2003 ▸) and catena-[(μ4-succinato)(μ2-succinato)bis­(μ2-4-pyridyl­isonicotin­amide)­dizinc] (Uebler et al., 2013 ▸).

Synthesis and crystallization

An aqueous solution of succinic acid (25 mmol, 3 g) was added to a solution of NaOH (50 mmol, 2 g) under stirring. An aqueous solution of CoCl2·6H2O (25 mmol, 5.95 g) was added and the reaction mixture stirred for 30 min at room temperature. The pink mixture obtained was filtered and left to dry. The pink crystalline material (0.86 mmol, 0.20 g) obtained was dissolved in water and added to a aqueous solution of isonicotinamide (1.71 mmol, 0.21 g). The resulting suspension was filtered and the filtrate allowed to stand. Red prismatic crystals were obtained from the filtrate in five weeks.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 3 ▸. The water and NH2 H atoms were located from difference-Fourier maps and freely refined. The C-bound H atoms were positioned geometrically and refined using a riding model: C—H = 0.93-0.97 Å with U iso(H) = 1.2U eq(C).

Table 3

Experimental details

Crystal data
Chemical formula	[Co(C6H6N2O)2(H2O)4](C4H4O4)
M r	491.32
Crystal system, space group	Monoclinic, P21/c
Temperature (K)	296
a, b, c (Å)	9.6757 (8), 10.0381 (8), 11.4947 (10)
β (°)	112.489 (6)
V (Å3)	1031.53 (15)
Z	2
Radiation type	Mo Kα
μ (mm−1)	0.89
Crystal size (mm)	0.68 × 0.49 × 0.37
Data collection
Diffractometer	Stoe IPDS 2
Absorption correction	Integration (X-RED32; Stoe & Cie, 2002 ▸)
T min, T max	0.664, 0.770
No. of measured, independent and observed [I > 2σ(I)] reflections	5748, 2125, 1709
R int	0.033
(sin θ/λ)max (Å−1)	0.628
Refinement
R[F 2 > 2σ(F 2)], wR(F 2), S	0.034, 0.087, 1.02
No. of reflections	2125
No. of parameters	166
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)	0.28, −0.38

Computer programs: X-AREA and X-RED32 (Stoe & Cie, 2002 ▸), SHELXS97 (Sheldrick, 2008 ▸), SHELXL2017 (Sheldrick, 2015 ▸), ORTEP-3 for Windows (Farrugia, 2012 ▸), Mercury (Macrae et al., 2008 ▸) and PLATON (Spek, 2009 ▸).

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S2056989018008861/su5446sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S2056989018008861/su5446Isup2.hkl

CCDC reference: 1842712

Additional supporting information: crystallographic information; 3D view; checkCIF report

[Co(C6H6N2O)2(H2O)4](C4H4O4)	F(000) = 510
Mr = 491.32	Dx = 1.582 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 9.6757 (8) Å	Cell parameters from 8789 reflections
b = 10.0381 (8) Å	θ = 3.1–30.2°
c = 11.4947 (10) Å	µ = 0.89 mm−1
β = 112.489 (6)°	T = 296 K
V = 1031.53 (15) Å3	Prism, red
Z = 2	0.68 × 0.49 × 0.37 mm

Stoe IPDS 2 diffractometer	2125 independent reflections
Radiation source: sealed X-ray tube, 12 x 0.4 mm long-fine focus	1709 reflections with I > 2σ(I)
Detector resolution: 6.67 pixels mm-1	Rint = 0.033
rotation method scans	θmax = 26.5°, θmin = 4.0°
Absorption correction: integration (X-RED32; Stoe & Cie, 2002)	h = −12→12
Tmin = 0.664, Tmax = 0.770	k = −12→12
5748 measured reflections	l = −14→10

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)] = 0.034	Hydrogen site location: mixed
wR(F2) = 0.087	H atoms treated by a mixture of independent and constrained refinement
S = 1.02	w = 1/[σ2(Fo2) + (0.0544P)2 + 0.0723P] where P = (Fo2 + 2Fc2)/3
2125 reflections	(Δ/σ)max < 0.001
166 parameters	Δρmax = 0.28 e Å−3
0 restraints	Δρmin = −0.38 e Å−3

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.

	x	y	z	Uiso*/Ueq
Co1	0.500000	0.500000	1.000000	0.02416 (13)
O3	0.40225 (19)	0.64528 (17)	0.85930 (16)	0.0323 (3)
O4	0.39411 (19)	0.34772 (15)	0.87503 (16)	0.0314 (3)
O2	0.44508 (19)	0.36520 (15)	0.66478 (15)	0.0372 (4)
O5	1.08679 (19)	0.30825 (16)	0.80841 (18)	0.0450 (4)
O1	0.2865 (2)	0.53407 (16)	0.62211 (16)	0.0413 (4)
N2	0.68645 (19)	0.47784 (15)	0.94294 (17)	0.0284 (4)
N1	1.0405 (3)	0.5081 (3)	0.7144 (3)	0.0523 (6)
C1	1.0166 (2)	0.4142 (2)	0.7847 (2)	0.0340 (5)
C2	0.9000 (2)	0.4398 (2)	0.8388 (2)	0.0291 (4)
C5	0.7381 (2)	0.5790 (2)	0.8958 (2)	0.0336 (5)
H5	0.700517	0.663743	0.898389	0.040*
C7	0.3809 (2)	0.4648 (2)	0.6004 (2)	0.0296 (4)
C3	0.8494 (3)	0.3354 (2)	0.8895 (2)	0.0348 (5)
H3	0.886482	0.249919	0.889455	0.042*
C6	0.8434 (2)	0.5649 (2)	0.8438 (2)	0.0343 (5)
H6	0.876190	0.638596	0.812443	0.041*
C4	0.7441 (3)	0.3579 (2)	0.9399 (2)	0.0353 (5)
H4	0.711309	0.286121	0.973646	0.042*
C8	0.4207 (3)	0.5013 (3)	0.4888 (3)	0.0535 (7)
H8A	0.368960	0.440472	0.420345	0.064*
H8B	0.382876	0.590118	0.461003	0.064*
H1A	0.982 (4)	0.584 (4)	0.697 (4)	0.083 (12)*
H1B	1.107 (4)	0.495 (3)	0.683 (4)	0.076 (11)*
H4A	0.403 (3)	0.355 (3)	0.812 (3)	0.035 (7)*
H3A	0.449 (3)	0.711 (3)	0.857 (3)	0.049 (8)*
H3B	0.373 (4)	0.612 (3)	0.792 (3)	0.055 (9)*
H4B	0.304 (4)	0.330 (3)	0.858 (3)	0.065 (10)*

	U11	U22	U33	U12	U13	U23
Co1	0.0267 (2)	0.02335 (19)	0.0296 (2)	−0.00065 (15)	0.01885 (15)	0.00042 (15)
O3	0.0388 (9)	0.0293 (8)	0.0331 (9)	−0.0031 (7)	0.0184 (7)	0.0019 (7)
O4	0.0343 (9)	0.0338 (8)	0.0335 (9)	−0.0035 (6)	0.0211 (7)	−0.0022 (6)
O2	0.0519 (10)	0.0311 (7)	0.0413 (9)	0.0079 (7)	0.0319 (8)	0.0046 (6)
O5	0.0432 (9)	0.0380 (9)	0.0700 (12)	−0.0002 (7)	0.0399 (9)	−0.0086 (8)
O1	0.0469 (9)	0.0431 (9)	0.0443 (10)	0.0117 (7)	0.0291 (8)	0.0043 (7)
N2	0.0296 (8)	0.0264 (9)	0.0373 (9)	−0.0010 (6)	0.0217 (7)	−0.0014 (7)
N1	0.0506 (12)	0.0602 (14)	0.0686 (15)	0.0086 (12)	0.0479 (12)	0.0121 (12)
C1	0.0285 (11)	0.0403 (12)	0.0406 (12)	−0.0040 (9)	0.0214 (10)	−0.0073 (9)
C2	0.0257 (10)	0.0333 (10)	0.0336 (11)	−0.0011 (8)	0.0174 (9)	−0.0032 (8)
C5	0.0368 (12)	0.0252 (10)	0.0475 (13)	0.0038 (8)	0.0260 (10)	0.0045 (9)
C7	0.0323 (10)	0.0304 (10)	0.0309 (11)	−0.0036 (8)	0.0175 (9)	−0.0010 (8)
C3	0.0368 (12)	0.0258 (10)	0.0515 (13)	−0.0003 (8)	0.0276 (10)	−0.0027 (9)
C6	0.0349 (11)	0.0320 (11)	0.0450 (13)	0.0004 (9)	0.0253 (10)	0.0076 (9)
C4	0.0400 (12)	0.0262 (10)	0.0516 (14)	−0.0018 (9)	0.0307 (11)	0.0014 (9)
C8	0.0439 (14)	0.0825 (19)	0.0455 (14)	0.0135 (14)	0.0298 (12)	0.0250 (14)

Co1—O4i	2.0794 (16)	N1—H1A	0.92 (4)
Co1—O3	2.1134 (15)	N1—H1B	0.87 (4)
Co1—O4	2.0795 (16)	C1—C2	1.504 (3)
Co1—N2i	2.1540 (16)	C2—C3	1.377 (3)
Co1—O3i	2.1134 (15)	C2—C6	1.381 (3)
Co1—N2	2.1540 (16)	C5—C6	1.372 (3)
O3—H3A	0.81 (3)	C5—H5	0.9300
O3—H3B	0.79 (4)	C7—C8	1.519 (3)
O4—H4A	0.77 (3)	C3—C4	1.370 (3)
O4—H4B	0.83 (4)	C3—H3	0.9300
O2—C7	1.257 (3)	C6—H6	0.9300
O5—C1	1.235 (3)	C4—H4	0.9300
O1—C7	1.247 (3)	C8—C8ii	1.456 (5)
N2—C4	1.333 (3)	C8—H8A	0.9700
N2—C5	1.334 (3)	C8—H8B	0.9700
N1—C1	1.317 (3)
O3—Co1—O3i	180	O5—C1—N1	122.8 (2)
O4i—Co1—O4	180	O5—C1—C2	119.4 (2)
N2i—Co1—N2	180	N1—C1—C2	117.8 (2)
O4i—Co1—O3	88.82 (7)	C3—C2—C6	117.62 (18)
O4—Co1—O3	91.18 (7)	C3—C2—C1	119.32 (18)
O4i—Co1—O3i	91.18 (7)	C6—C2—C1	123.03 (19)
O4—Co1—O3i	88.82 (7)	N2—C5—C6	123.66 (19)
O4i—Co1—N2i	87.85 (6)	N2—C5—H5	118.2
O4—Co1—N2i	92.15 (7)	C6—C5—H5	118.2
O3—Co1—N2i	88.85 (6)	O1—C7—O2	124.09 (19)
O3i—Co1—N2i	91.15 (6)	O1—C7—C8	118.4 (2)
O4i—Co1—N2	92.15 (7)	O2—C7—C8	117.47 (19)
O4—Co1—N2	87.85 (6)	C4—C3—C2	119.73 (19)
O3—Co1—N2	91.15 (6)	C4—C3—H3	120.1
O3i—Co1—N2	88.85 (6)	C2—C3—H3	120.1
Co1—O3—H3A	120 (2)	C5—C6—C2	118.99 (19)
Co1—O3—H3B	110 (2)	C5—C6—H6	120.5
H3A—O3—H3B	108 (3)	C2—C6—H6	120.5
Co1—O4—H4A	112 (2)	N2—C4—C3	123.14 (19)
Co1—O4—H4B	121 (2)	N2—C4—H4	118.4
H4A—O4—H4B	106 (3)	C3—C4—H4	118.4
C4—N2—C5	116.83 (17)	C8ii—C8—C7	115.9 (3)
C4—N2—Co1	120.60 (13)	C8ii—C8—H8A	108.3
C5—N2—Co1	122.14 (13)	C7—C8—H8A	108.3
C1—N1—H1A	119 (3)	C8ii—C8—H8B	108.3
C1—N1—H1B	119 (2)	C7—C8—H8B	108.3
H1A—N1—H1B	122 (3)	H8A—C8—H8B	107.4
O5—C1—C2—C3	−14.5 (3)	N2—C5—C6—C2	0.2 (4)
N1—C1—C2—C3	166.3 (2)	C3—C2—C6—C5	−1.4 (3)
O5—C1—C2—C6	163.5 (2)	C1—C2—C6—C5	−179.5 (2)
N1—C1—C2—C6	−15.7 (3)	C5—N2—C4—C3	−1.2 (4)
C4—N2—C5—C6	1.1 (4)	Co1—N2—C4—C3	171.39 (19)
Co1—N2—C5—C6	−171.37 (19)	C2—C3—C4—N2	0.0 (4)
C6—C2—C3—C4	1.4 (4)	O1—C7—C8—C8ii	136.1 (3)
C1—C2—C3—C4	179.5 (2)	O2—C7—C8—C8ii	−44.5 (5)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3B···O1	0.79 (4)	1.97 (4)	2.756 (3)	176 (3)
O4—H4A···O2	0.77 (3)	1.88 (3)	2.651 (2)	174 (3)
O3—H3A···O2iii	0.81 (3)	1.92 (3)	2.729 (2)	175 (3)
O4—H4B···O5iv	0.83 (4)	1.97 (4)	2.801 (2)	174 (3)
N1—H1A···O5v	0.92 (4)	2.34 (4)	3.227 (3)	160 (3)
N1—H1B···O1vi	0.87 (4)	2.14 (4)	2.966 (3)	160 (3)
C5—H5···O2iii	0.93	2.41	3.307 (3)	161
C6—H6···O5v	0.93	2.31	3.223 (3)	167