Diaqua­bis­(4-meth­oxy­benzoato-κO)bis­(nicotinamide-κN¹)nickel(II) dihydrate

In the mononuclear title compound, [Ni(C₈H₇O₃)₂(C₆H₆N₂O)₂(H₂O)₂]·2H₂O, the Ni^II ion is located on a crystallographic inversion center. The asymmetric unit further contains one 4-meth­oxy­benzoate anion, one nicotinamide (NA) ligand and one coordinated and one uncoordinated water mol­ecule; all ligands are monodentate. The four O atoms in the equatorial plane around the Ni^II ion form a slightly distorted square-planar arrangement, while the slightly distorted octa­hedral coordination is completed by the two pyridine N atoms of the NA ligands in the axial positions. The dihedral angle between the carboxyl­ate group and the attached benzene ring is 7.2 (1)°, while the pyridine and benzene rings are oriented at a dihedral angle of 72.80 (4)°. An intra­molecular O—H...O hydrogen bond links the uncoordinated water mol­ecule to one of the carboxyl­ate groups. In the crystal structure, inter­molecular O—H...O, N—H...O and C—H...O hydrogen bonds link the mol­ecules into a three-dimensional network.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.026
• wR factor = 0.067
• Data-to-parameter ratio = 16.4

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Ni1    --  O5      ..       8.41 su
PLAT420_ALERT_2_C D-H Without Acceptor       N2     -   H21    ...          ?
PLAT042_ALERT_1_C Calc. and Reported MoietyFormula Strings  Differ          ?
PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L=  0.600         18

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

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

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S1. Comment

As a part of our ongoing investigation on transition metal complexes of nicotinamide (NA), one form of niacin (Krishnamachari, 1974), and/or the nicotinic acid derivative N,N-diethylnicotinamide (DENA), an important respiratory stimulant (Bigoli et al., 1972), the title compound was synthesized and its crystal structure is reported herein.

The title compound, (I), is a mononuclear complex, where the Ni^II ion is located on a crystallographic inversion center. The asymmetric unit contains one 4-methoxybenzoate (PMOB) anion, one nicotinamide (NA) ligand and one coordinated and one uncoordinated water molecules, all ligands are monodentate (Fig. 1). The crystal structures of some NA and/or DENA complexes of Cu^II, Co^II, Ni^II, Mn^II and Zn^II ions, [Cu(C₇H₅O₂)₂(C₁₀H₁₄N₂O)₂], (II) (Hökelek et al., 1996), [Co(C₆H₆N₂O)₂(C₇H₄NO₄)₂(H₂O)₂], (III) (Hökelek & Necefoğlu, 1998), [Ni(C₇H₄ClO₂)₂(C₆H₆N₂O)₂(H₂O)₂], (IV) (Hökelek et al., 2009a), [Ni(C₈H₇O₂)₂(C₆H₆N₂O)₂(H₂O)₂], (V) (Necefoğlu et al., 2010), [Mn(C₇H₄ClO₂)₂(C₁₀H₁₄N₂O)₂(H₂O)₂], (VI) (Hökelek et al., 2009b) and [Zn(C₇H₄BrO₂)₂(C₆H₆N₂O)₂(H₂O)₂], (VII) (Hökelek et al., 2009c) have also been reported. In (II), two benzoate ions are coordinated to the Cu atom as bidentate ligands, while in other structures all ligands being monodentate.

The four O atoms (O1, O5, and the symmetry-related atoms, O1', O5') in the equatorial plane around the Ni^II ion form a slightly distorted square-planar arrangement, while the slightly distorted octahedral coordination is completed by the two N atoms of the NA ligands (N1, N1') in the axial positions (Fig. 1). The near equality of the C1—O1 [1.2681 (15) Å] and C1—O2 [1.2644 (16) Å] bonds in the carboxylate group indicates a delocalized bonding arrangement, rather than localized single and double bonds. The average Ni—O bond length is 2.0633 (9) Å (Table 1), and the Ni^II ion is displaced out of the least-squares plane of the carboxylate group (O1/C1/O2) by 0.7794 (1) Å. The dihedral angle between the planar carboxylate group and the benzene ring A (C2—C7) is 7.2 (1)°, while that between rings A and B (N1/C9—C13) is 72.80 (4)°. An intramolecular O—H···O hydrogen bond (Table 2) links the uncoordinated water molecule to one of the carboxylate groups (Fig. 1).

In the crystal structure, intermolecular O—H···O, N—H···O and C—H···O hydrogen bonds (Table 2) link the molecules into a three-dimensional network.

Related literature

For niacin, see: Krishnamachari (1974). For N,N-diethylnicotinamide, see: Bigoli et al. (1972). For related structures, see: Hökelek et al. (1996,2009a,b,c); Hökelek & Necefoğlu (1998); Necefoğlu et al. (2010).

S2. Experimental

The title compound was prepared by the reaction of NiSO₄.6H₂O (2.63 g, 10 mmol) in H₂O (50 ml) and nicotinamide (2.44 g, 20 mmol) in H₂O (50 ml) with sodium 4-methoybenzoate (3.48 g, 20 mmol) in H₂O (100 ml). The mixture was filtered and set aside to crystallize at ambient temperature for one week, giving blue single crystals.

S3. Refinement

Atoms H21, H22 (for NH₂) and H51, H52, H61, H62 (for H₂O) were located in a difference Fourier map and refined isotropically. The remaining H atoms were positioned geometrically with C—H = 0.95 and 0.98 Å for aromatic and methyl H atoms and constrained to ride on their parent atoms, with U_iso(H) = xU_eq(C), where x = 1.5 for methyl H and x = 1.2 for aromatic H atoms.

Computing details

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures

Fig. 1. The molecular structure of the title compound with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. Primed atoms are generated by the symmetry operator: (') 2 - x, 1 - y, 1 -z. Dashed lines indicate the hydrogen-bonding.

Diaquabis(4-methoxybenzoato-κO)bis(nicotinamide-κN¹)nickel(II) dihydrate

Crystal data

[Ni(C8H7O3)2(C6H6N2O)2(H2O)2]·2H2O	Z = 1
Mr = 677.28	F(000) = 354
Triclinic, P1	Dx = 1.505 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.1279 (2) Å	Cell parameters from 7665 reflections
b = 9.7006 (2) Å	θ = 2.2–28.4°
c = 10.0636 (3) Å	µ = 0.72 mm^−1
α = 101.637 (3)°	T = 100 K
β = 91.634 (2)°	Block, blue
γ = 105.137 (3)°	0.35 × 0.26 × 0.19 mm
V = 747.42 (4) Å^3

Data collection

Bruker Kappa APEXII CCD area-detector diffractometer	3740 independent reflections
Radiation source: fine-focus sealed tube	3454 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.024
φ and ω scans	θmax = 28.4°, θmin = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −10→10
Tmin = 0.797, Tmax = 0.871	k = −12→12
13749 measured reflections	l = −13→13

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)] = 0.026	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.067	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0304P)^2 + 0.3607P] where P = (Fo^2 + 2Fc^2)/3
3740 reflections	(Δ/σ)max = 0.001
228 parameters	Δρmax = 0.41 e Å^−3
0 restraints	Δρmin = −0.32 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
Ni1	1.0000	0.5000	0.5000	0.01031 (7)
O1	0.84093 (11)	0.34709 (9)	0.34598 (9)	0.01344 (18)
O2	0.97158 (13)	0.37223 (10)	0.15603 (9)	0.0186 (2)
O3	0.51173 (13)	−0.29261 (10)	0.00777 (10)	0.0227 (2)
O4	1.23447 (12)	−0.12322 (10)	0.38559 (10)	0.01808 (19)
O5	0.84001 (12)	0.41637 (10)	0.63798 (10)	0.01381 (18)
H51	0.824 (2)	0.328 (2)	0.6383 (18)	0.026 (5)*
H52	0.880 (3)	0.466 (2)	0.710 (2)	0.033 (5)*
O6	1.09929 (14)	0.36688 (11)	−0.10135 (11)	0.0217 (2)
H61	1.060 (2)	0.3618 (18)	−0.0275 (19)	0.020*
H62	1.093 (2)	0.444 (2)	−0.1194 (17)	0.020*
N1	1.15013 (13)	0.35208 (11)	0.50331 (10)	0.0123 (2)
N2	1.00731 (15)	−0.08680 (12)	0.27740 (11)	0.0164 (2)
H21	0.955 (2)	−0.027 (2)	0.2615 (17)	0.021 (4)*
H22	0.976 (2)	−0.178 (2)	0.2312 (19)	0.028 (5)*
C1	0.86838 (16)	0.29893 (13)	0.22424 (12)	0.0132 (2)
C2	0.77440 (16)	0.14302 (13)	0.16204 (12)	0.0136 (2)
C3	0.65161 (17)	0.06356 (14)	0.23287 (13)	0.0166 (3)
H3	0.6270	0.1096	0.3197	0.020*
C4	0.56565 (17)	−0.08093 (14)	0.17828 (14)	0.0186 (3)
H4	0.4811	−0.1330	0.2268	0.022*
C5	0.60317 (17)	−0.15037 (14)	0.05176 (13)	0.0166 (3)
C6	0.72616 (18)	−0.07365 (14)	−0.01936 (13)	0.0193 (3)
H6	0.7531	−0.1207	−0.1049	0.023*
C7	0.80961 (18)	0.07279 (14)	0.03580 (13)	0.0178 (3)
H7	0.8920	0.1256	−0.0138	0.021*
C8	0.5467 (2)	−0.37024 (15)	−0.11975 (15)	0.0267 (3)
H8A	0.4740	−0.4712	−0.1386	0.040*
H8B	0.6672	−0.3705	−0.1161	0.040*
H8C	0.5229	−0.3223	−0.1922	0.040*
C9	1.30962 (17)	0.40473 (14)	0.56440 (13)	0.0165 (3)
H9	1.3474	0.5053	0.6080	0.020*
C10	1.42177 (17)	0.31926 (14)	0.56686 (14)	0.0191 (3)
H10	1.5328	0.3600	0.6130	0.023*
C11	1.36869 (17)	0.17315 (14)	0.50057 (13)	0.0156 (2)
H11	1.4428	0.1119	0.5007	0.019*
C12	1.20523 (16)	0.11758 (13)	0.43385 (12)	0.0124 (2)
C13	1.09960 (16)	0.21032 (13)	0.43965 (12)	0.0124 (2)
H13	0.9867	0.1717	0.3967	0.015*
C14	1.14890 (16)	−0.04076 (13)	0.36228 (12)	0.0132 (2)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ni1	0.01171 (11)	0.00792 (11)	0.01082 (11)	0.00341 (8)	−0.00027 (8)	0.00012 (8)
O1	0.0145 (4)	0.0117 (4)	0.0131 (4)	0.0045 (3)	−0.0005 (3)	−0.0006 (3)
O2	0.0262 (5)	0.0119 (4)	0.0144 (4)	0.0005 (4)	0.0021 (4)	0.0015 (3)
O3	0.0265 (5)	0.0112 (4)	0.0244 (5)	−0.0007 (4)	−0.0025 (4)	−0.0016 (4)
O4	0.0195 (5)	0.0117 (4)	0.0246 (5)	0.0068 (4)	0.0026 (4)	0.0039 (4)
O5	0.0164 (4)	0.0100 (4)	0.0140 (4)	0.0034 (3)	−0.0002 (3)	0.0007 (3)
O6	0.0344 (6)	0.0147 (5)	0.0164 (5)	0.0076 (4)	0.0037 (4)	0.0025 (4)
N1	0.0140 (5)	0.0108 (5)	0.0123 (5)	0.0044 (4)	0.0013 (4)	0.0018 (4)
N2	0.0217 (6)	0.0112 (5)	0.0167 (5)	0.0071 (4)	−0.0002 (4)	0.0010 (4)
C1	0.0146 (6)	0.0117 (5)	0.0137 (6)	0.0052 (4)	−0.0024 (4)	0.0017 (4)
C2	0.0151 (6)	0.0112 (5)	0.0135 (6)	0.0039 (4)	−0.0024 (5)	0.0007 (4)
C3	0.0175 (6)	0.0152 (6)	0.0157 (6)	0.0043 (5)	0.0021 (5)	0.0006 (5)
C4	0.0174 (6)	0.0152 (6)	0.0211 (6)	0.0011 (5)	0.0022 (5)	0.0033 (5)
C5	0.0173 (6)	0.0111 (6)	0.0190 (6)	0.0025 (5)	−0.0049 (5)	0.0006 (5)
C6	0.0261 (7)	0.0152 (6)	0.0136 (6)	0.0041 (5)	0.0007 (5)	−0.0018 (5)
C7	0.0223 (6)	0.0139 (6)	0.0144 (6)	0.0016 (5)	0.0019 (5)	0.0014 (5)
C8	0.0364 (8)	0.0146 (6)	0.0236 (7)	0.0044 (6)	−0.0065 (6)	−0.0038 (5)
C9	0.0165 (6)	0.0115 (6)	0.0195 (6)	0.0036 (5)	−0.0013 (5)	−0.0002 (5)
C10	0.0140 (6)	0.0169 (6)	0.0250 (7)	0.0046 (5)	−0.0031 (5)	0.0013 (5)
C11	0.0161 (6)	0.0150 (6)	0.0185 (6)	0.0085 (5)	0.0029 (5)	0.0043 (5)
C12	0.0158 (6)	0.0104 (5)	0.0120 (5)	0.0044 (4)	0.0041 (4)	0.0034 (4)
C13	0.0140 (6)	0.0116 (5)	0.0117 (5)	0.0036 (4)	0.0014 (4)	0.0028 (4)
C14	0.0169 (6)	0.0110 (5)	0.0129 (5)	0.0047 (4)	0.0061 (5)	0.0037 (4)

Geometric parameters (Å, º)

Ni1—O1	2.0569 (9)	C2—C7	1.3904 (18)
Ni1—O1^i	2.0569 (9)	C3—C4	1.3822 (18)
Ni1—O5	2.0697 (9)	C3—H3	0.95
Ni1—O5^i	2.0697 (9)	C4—C5	1.3970 (19)
Ni1—N1	2.1167 (10)	C4—H4	0.95
Ni1—N1^i	2.1167 (10)	C5—C6	1.3902 (19)
O1—C1	1.2681 (15)	C6—C7	1.3941 (18)
O2—C1	1.2644 (16)	C6—H6	0.95
O3—C5	1.3607 (15)	C7—H7	0.95
O3—C8	1.4274 (18)	C8—H8A	0.98
O4—C14	1.2392 (15)	C8—H8B	0.98
O5—H51	0.83 (2)	C8—H8C	0.98
O5—H52	0.79 (2)	C9—C10	1.3858 (18)
O6—H61	0.823 (18)	C9—H9	0.95
O6—H62	0.818 (18)	C10—C11	1.3867 (18)
N1—C9	1.3421 (16)	C10—H10	0.95
N1—C13	1.3434 (15)	C11—C12	1.3913 (18)
N2—C14	1.3324 (17)	C11—H11	0.95
N2—H21	0.839 (18)	C12—C13	1.3910 (17)
N2—H22	0.877 (19)	C12—C14	1.5017 (16)
C1—C2	1.5001 (17)	C13—H13	0.95
C2—C3	1.3995 (18)
O1^i—Ni1—O1	180.0	C3—C4—C5	119.95 (12)
O1—Ni1—O5	88.52 (4)	C3—C4—H4	120.0
O1^i—Ni1—O5	91.48 (4)	C5—C4—H4	120.0
O1—Ni1—O5^i	91.48 (4)	O3—C5—C4	115.16 (12)
O1^i—Ni1—O5^i	88.52 (4)	O3—C5—C6	124.95 (12)
O1—Ni1—N1	88.64 (4)	C6—C5—C4	119.89 (12)
O1^i—Ni1—N1	91.36 (4)	C5—C6—C7	119.52 (12)
O1—Ni1—N1^i	91.36 (4)	C5—C6—H6	120.2
O1^i—Ni1—N1^i	88.64 (4)	C7—C6—H6	120.2
O5—Ni1—O5^i	180.000 (1)	C2—C7—C6	121.20 (12)
O5—Ni1—N1	93.21 (4)	C2—C7—H7	119.4
O5^i—Ni1—N1	86.79 (4)	C6—C7—H7	119.4
O5—Ni1—N1^i	86.79 (4)	O3—C8—H8A	109.5
O5^i—Ni1—N1^i	93.21 (4)	O3—C8—H8B	109.5
N1—Ni1—N1^i	180.0	O3—C8—H8C	109.5
C1—O1—Ni1	130.22 (8)	H8A—C8—H8B	109.5
C5—O3—C8	117.74 (11)	H8A—C8—H8C	109.5
Ni1—O5—H51	117.6 (12)	H8B—C8—H8C	109.5
Ni1—O5—H52	104.9 (14)	N1—C9—C10	123.11 (12)
H51—O5—H52	111.1 (19)	N1—C9—H9	118.4
H62—O6—H61	108.0 (17)	C10—C9—H9	118.4
C9—N1—Ni1	118.24 (8)	C9—C10—C11	118.69 (12)
C9—N1—C13	117.80 (11)	C9—C10—H10	120.7
C13—N1—Ni1	123.79 (8)	C11—C10—H10	120.7
C14—N2—H21	120.0 (12)	C10—C11—C12	118.98 (11)
C14—N2—H22	119.6 (12)	C10—C11—H11	120.5
H21—N2—H22	120.1 (17)	C12—C11—H11	120.5
O1—C1—C2	116.29 (11)	C11—C12—C14	118.60 (11)
O2—C1—O1	124.22 (11)	C13—C12—C11	118.44 (11)
O2—C1—C2	119.46 (11)	C13—C12—C14	122.93 (11)
C3—C2—C1	120.07 (11)	N1—C13—C12	122.95 (11)
C7—C2—C1	121.44 (12)	N1—C13—H13	118.5
C7—C2—C3	118.47 (11)	C12—C13—H13	118.5
C2—C3—H3	119.5	O4—C14—N2	122.82 (12)
C4—C3—C2	120.95 (12)	O4—C14—C12	118.87 (11)
C4—C3—H3	119.5	N2—C14—C12	118.31 (11)
O5—Ni1—O1—C1	−160.75 (10)	C1—C2—C3—C4	−178.93 (12)
O5^i—Ni1—O1—C1	19.25 (10)	C7—C2—C3—C4	−0.71 (19)
N1—Ni1—O1—C1	−67.50 (10)	C1—C2—C7—C6	177.72 (12)
N1^i—Ni1—O1—C1	112.50 (10)	C3—C2—C7—C6	−0.5 (2)
O1—Ni1—N1—C9	162.56 (10)	C2—C3—C4—C5	1.2 (2)
O1^i—Ni1—N1—C9	−17.44 (10)	C8—O3—C5—C4	−178.85 (12)
O1—Ni1—N1—C13	−12.62 (10)	C8—O3—C5—C6	1.3 (2)
O1^i—Ni1—N1—C13	167.38 (10)	C3—C4—C5—O3	179.75 (12)
O5—Ni1—N1—C9	−109.01 (10)	C3—C4—C5—C6	−0.4 (2)
O5^i—Ni1—N1—C9	70.99 (10)	O3—C5—C6—C7	179.07 (13)
O5—Ni1—N1—C13	75.81 (10)	C4—C5—C6—C7	−0.7 (2)
O5^i—Ni1—N1—C13	−104.19 (10)	C5—C6—C7—C2	1.2 (2)
Ni1—O1—C1—O2	−29.75 (18)	N1—C9—C10—C11	1.5 (2)
Ni1—O1—C1—C2	148.20 (9)	C9—C10—C11—C12	0.1 (2)
Ni1—N1—C9—C10	−176.80 (10)	C10—C11—C12—C13	−1.78 (19)
C13—N1—C9—C10	−1.33 (19)	C10—C11—C12—C14	179.97 (11)
Ni1—N1—C13—C12	174.71 (9)	C11—C12—C13—N1	2.04 (18)
C9—N1—C13—C12	−0.49 (18)	C14—C12—C13—N1	−179.79 (11)
O1—C1—C2—C3	6.12 (17)	C11—C12—C14—O4	13.48 (17)
O1—C1—C2—C7	−172.05 (12)	C11—C12—C14—N2	−167.30 (12)
O2—C1—C2—C3	−175.83 (11)	C13—C12—C14—O4	−164.68 (12)
O2—C1—C2—C7	6.00 (18)	C13—C12—C14—N2	14.53 (18)

Symmetry code: (i) −x+2, −y+1, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H22···O6^ii	0.88 (2)	1.96 (2)	2.8306 (16)	170 (2)
O5—H51···O4^iii	0.83 (2)	1.88 (2)	2.7074 (14)	171 (2)
O5—H52···O2^i	0.79 (2)	1.95 (2)	2.7040 (14)	159 (2)
O6—H61···O2	0.82 (2)	1.99 (2)	2.8136 (14)	174 (2)
O6—H62···O2^iv	0.82 (2)	2.08 (2)	2.8887 (15)	169 (2)
C9—H9···O1^i	0.95	2.35	2.9719 (16)	123
C10—H10···O5^v	0.95	2.41	3.2973 (17)	156

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