trans-Di­aqua­bis(2-pyridyl­ethanol-N,O)­nickel(II) disaccharinate

The title complex, [Ni(pyet)₂(H₂O)₂](sac)₂ (sac⁻ is the saccharinate anion, C₇H₄NO₃S⁻, and pyet is 2-pyridyl­ethanol, C₇H₉NO), is built of discrete sac⁻ and [Ni(H₂O)₂(pyet)₂]²⁺ ions. The Co²⁺ ion sits on a centre of symmetry and exhibits a distorted octahedral geometry, formed by two bidentate pyet and two water mol­ecules. The crystal structure is stabilized by hydrogen-bonding and weak aromatic π–π-stacking interactions between the planar sac⁻ ions, forming a three-dimensional network.

Key indicators

• Single-crystal X-ray study
• T = 133 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.032
• wR factor = 0.096
• Data-to-parameter ratio = 19.6

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

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S1. Comment

The structure of the title complex, (I), is shown in Fig. 1. The nickel(II) complex is isostructural with the corresponding cobalt(II) complex and consists of a complex cation, [Ni(H₂O)₂(pyet)₂]²⁺, and two saccharinate (sac) anions. The crystal is centrosymmetric and the Ni^II ion located at the centre of symmetry is coordinated by a pair of neutral 2-pyridylethanol (pyet) ligands and two water molecules having distorted octahedral geometry. The sac ions are not in the primary coordination sphere, being as a counter-ion. Two pyet ligands are chelated to the Ni^II ion through the N and hydroxyl O atoms, forming two symmetrically six-membered chelate rings. The two pyet ligands form the equatorial plane of the coordination octahedron, while two water molecules occupy the axial positions with a trans configuration.

The crystal packing is shown in Fig. 2. Packing of molecules in (I) is very similar to its corresponding cobalt(II) complex (Yilmaz et al., 2002). The discrete cations and anions are linked by hydrogen bonds, as well as π–π interactions. The parallel stacking of pairs of the sac ions results in weak π–π interactions (Cg···Cg > 4.0 Å). The H atoms of the water molecules (O4) and hydroxyl group (O3) of pyet form O—H···O hydrogen bonds with the sulfonyl (O1) and carbonyl (O21) O atoms of neighboring sac anions. Additionally, two weak C—H···O interactions between H atoms of the py ring and the carbonyl and sulfonyl O atoms of the adjacent sac ions occur. The ions are held together by hydrogen bonds and weak π–π interactions, creating a three-dimensional network.

S2. Experimental

Previously prepared [Ni(sac)₂(H₂O)₄]·2H₂O (1.0 mmol, 0.53 g) was dissolved in methanol (30 ml) at 303 K with stirring. Pyet (0.25 g, 2.0 mmol) was then added to the solution dropwise. The resulting solution was allowed to evaporate slowly for crystallization at room temperature. Suitable single crystals obtained within a week were collected by suction filtration, washed with acetone and dried in air.

S3. Refinement

H atoms of the hydroxyl group and water molecules were refined freely, while H atoms bonded to carbon were included using a riding model, starting from calculated positions.

Computing details

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP (Siemens, 1994); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. A molecular view of [Ni(H2O)2(pyet)2](sac)2 (40% displacement ellipsoids). [Symmetry code: (i) −x, 1 − y, −z.]
	Fig. 2. Packing diagram of [Ni(H2O)2(pyet)2](sac)2, showing the hydrogen-bonding scheme.

trans-Diaquabis(2-pyridylethanol-N,O)nickel(II) disaccharinate

Crystal data

[Ni(C7H9NO)2(H2O)2]·(C7H4NO3S)2	F(000) = 732
Mr = 705.39	Dx = 1.617 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
a = 8.8009 (6) Å	Cell parameters from 5714 reflections
b = 8.7664 (6) Å	θ = 2.2–30.5°
c = 19.0840 (14) Å	µ = 0.88 mm^−1
β = 100.262 (3)°	T = 133 K
V = 1448.82 (18) Å^3	Irregular, pale-blue
Z = 2	0.24 × 0.15 × 0.13 mm

Data collection

Bruker SMART 1000CCD diffractometer	4249 independent reflections
Radiation source: fine-focus sealed tube	3604 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.030
Detector resolution: 8.192 pixels mm^-1	θmax = 30.0°, θmin = 2.2°
ω and ψ scans	h = −12→12
Absorption correction: multi-scan (SADABS; Bruker, 1998)	k = −12→12
Tmin = 0.826, Tmax = 0.928	l = −26→26
25119 measured reflections

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)] = 0.032	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.096	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	w = 1/[σ^2(Fo^2) + (0.0635P)^2 + 0.2009P] where P = (Fo^2 + 2Fc^2)/3
4249 reflections	(Δ/σ)max = 0.001
217 parameters	Δρmax = 1.04 e Å^−3
0 restraints	Δρmin = −0.28 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
Ni	0.0000	0.5000	0.0000	0.01342 (8)
S1	0.54586 (4)	0.28708 (4)	0.132706 (18)	0.01640 (9)
N1	0.40479 (16)	0.29573 (15)	0.06600 (7)	0.0197 (3)
N2	0.02723 (14)	0.34582 (14)	0.08366 (6)	0.0157 (2)
O1	0.68479 (14)	0.35220 (13)	0.11455 (6)	0.0250 (3)
O2	0.50389 (15)	0.34895 (14)	0.19650 (6)	0.0254 (3)
O3	−0.03462 (14)	0.67465 (13)	0.06800 (6)	0.0191 (2)
H3	−0.105 (3)	0.731 (3)	0.0523 (14)	0.049 (8)*
O4	0.23567 (13)	0.54793 (13)	0.01537 (6)	0.0179 (2)
H4A	0.261 (3)	0.578 (3)	−0.0182 (12)	0.028 (6)*
H4B	0.290 (3)	0.473 (3)	0.0285 (13)	0.037 (7)*
O21	0.24888 (14)	0.13046 (14)	−0.00756 (6)	0.0252 (3)
C11	0.41984 (19)	−0.12674 (19)	0.07775 (9)	0.0236 (3)
H11	0.3404	−0.1667	0.0422	0.028*
C12	0.5172 (2)	−0.22303 (19)	0.12350 (9)	0.0261 (3)
H12	0.5043	−0.3304	0.1190	0.031*
C13	0.6332 (2)	−0.16376 (19)	0.17576 (9)	0.0246 (3)
H13	0.6983	−0.2317	0.2062	0.030*
C14	0.65568 (19)	−0.00735 (17)	0.18432 (9)	0.0202 (3)
H14	0.7344	0.0333	0.2200	0.024*
C15	0.55770 (17)	0.08643 (17)	0.13824 (8)	0.0166 (3)
C16	0.44254 (18)	0.02906 (17)	0.08569 (8)	0.0176 (3)
C21	0.35498 (18)	0.15554 (18)	0.04337 (8)	0.0189 (3)
C31	−0.01567 (19)	0.19835 (18)	0.06905 (9)	0.0212 (3)
H31	−0.0581	0.1721	0.0213	0.025*
C32	−0.0007 (2)	0.08472 (19)	0.12012 (10)	0.0266 (3)
H32	−0.0330	−0.0166	0.1076	0.032*
C33	0.0627 (2)	0.1215 (2)	0.19034 (10)	0.0291 (4)
H33	0.0763	0.0460	0.2266	0.035*
C34	0.1053 (2)	0.2722 (2)	0.20562 (9)	0.0251 (3)
H34	0.1492	0.3005	0.2530	0.030*
C35	0.08411 (18)	0.38188 (18)	0.15212 (8)	0.0193 (3)
C36	0.1156 (2)	0.54779 (19)	0.16934 (8)	0.0227 (3)
H36A	0.2032	0.5822	0.1471	0.027*
H36B	0.1460	0.5597	0.2215	0.027*
C37	−0.0239 (2)	0.64808 (19)	0.14314 (8)	0.0238 (3)
H37A	−0.1189	0.5972	0.1522	0.029*
H37B	−0.0131	0.7465	0.1690	0.029*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ni	0.01362 (13)	0.01412 (13)	0.01219 (13)	−0.00042 (9)	0.00140 (9)	0.00021 (8)
S1	0.01643 (17)	0.01530 (17)	0.01736 (17)	0.00079 (12)	0.00272 (13)	0.00033 (12)
N1	0.0195 (6)	0.0179 (6)	0.0204 (6)	0.0047 (5)	0.0003 (5)	0.0011 (5)
N2	0.0140 (5)	0.0180 (6)	0.0147 (5)	0.0003 (4)	0.0020 (4)	0.0009 (4)
O1	0.0203 (6)	0.0249 (6)	0.0301 (6)	−0.0034 (5)	0.0049 (5)	0.0066 (5)
O2	0.0298 (6)	0.0245 (6)	0.0222 (5)	0.0019 (5)	0.0054 (5)	−0.0062 (4)
O3	0.0220 (5)	0.0189 (5)	0.0150 (5)	0.0046 (4)	−0.0003 (4)	−0.0009 (4)
O4	0.0157 (5)	0.0178 (5)	0.0198 (5)	0.0002 (4)	0.0023 (4)	0.0037 (4)
O21	0.0213 (6)	0.0278 (6)	0.0236 (5)	0.0058 (5)	−0.0037 (5)	−0.0046 (5)
C11	0.0218 (8)	0.0200 (7)	0.0280 (8)	0.0007 (6)	0.0020 (6)	−0.0037 (6)
C12	0.0296 (9)	0.0159 (7)	0.0330 (8)	0.0013 (6)	0.0064 (7)	0.0006 (6)
C13	0.0254 (8)	0.0219 (7)	0.0267 (8)	0.0049 (6)	0.0049 (6)	0.0061 (6)
C14	0.0196 (7)	0.0214 (7)	0.0193 (7)	0.0020 (6)	0.0025 (6)	0.0025 (5)
C15	0.0162 (7)	0.0165 (6)	0.0176 (6)	0.0008 (5)	0.0043 (5)	0.0008 (5)
C16	0.0166 (7)	0.0178 (6)	0.0187 (6)	0.0022 (5)	0.0037 (5)	−0.0002 (5)
C21	0.0177 (7)	0.0213 (7)	0.0178 (6)	0.0049 (6)	0.0031 (5)	−0.0014 (5)
C31	0.0191 (7)	0.0209 (7)	0.0232 (7)	−0.0006 (6)	0.0030 (6)	0.0015 (6)
C32	0.0263 (8)	0.0190 (7)	0.0340 (9)	−0.0012 (6)	0.0038 (7)	0.0058 (6)
C33	0.0266 (9)	0.0274 (8)	0.0322 (9)	0.0000 (7)	0.0020 (7)	0.0086 (7)
C34	0.0246 (8)	0.0295 (8)	0.0206 (7)	0.0005 (6)	0.0024 (6)	0.0061 (6)
C35	0.0162 (7)	0.0224 (7)	0.0191 (7)	0.0010 (5)	0.0024 (5)	0.0017 (6)
C36	0.0256 (8)	0.0230 (7)	0.0177 (7)	−0.0012 (6)	−0.0007 (6)	0.0004 (6)
C37	0.0303 (9)	0.0214 (7)	0.0197 (7)	0.0037 (6)	0.0044 (6)	−0.0013 (6)

Geometric parameters (Å, º)

Ni—O3	2.0645 (11)	C13—C14	1.391 (2)
Ni—N2	2.0729 (12)	C13—H13	0.9500
Ni—O4	2.0851 (11)	C14—C15	1.387 (2)
S1—O2	1.4398 (12)	C14—H14	0.9500
S1—O1	1.4463 (12)	C15—C16	1.387 (2)
S1—N1	1.6138 (13)	C16—C21	1.501 (2)
S1—C15	1.7641 (15)	C31—C32	1.383 (2)
N1—C21	1.350 (2)	C31—H31	0.9500
N2—C35	1.3507 (19)	C32—C33	1.395 (3)
N2—C31	1.3616 (19)	C32—H32	0.9500
O3—C37	1.4391 (19)	C33—C34	1.390 (3)
O3—H3	0.81 (3)	C33—H33	0.9500
O4—H4A	0.76 (2)	C34—C35	1.391 (2)
O4—H4B	0.82 (3)	C34—H34	0.9500
O21—C21	1.2417 (18)	C35—C36	1.506 (2)
C11—C16	1.385 (2)	C36—C37	1.520 (2)
C11—C12	1.394 (2)	C36—H36A	0.9900
C11—H11	0.9500	C36—H36B	0.9900
C12—C13	1.394 (2)	C37—H37A	0.9900
C12—H12	0.9500	C37—H37B	0.9900
O3^i—Ni—O3	180.00	C14—C15—C16	122.37 (14)
O3—Ni—N2^i	89.48 (5)	C14—C15—S1	130.73 (12)
O3—Ni—N2	90.52 (5)	C16—C15—S1	106.89 (11)
N2^i—Ni—N2	180.00	C11—C16—C15	120.62 (14)
O3^i—Ni—O4	89.05 (5)	C11—C16—C21	128.27 (14)
O3—Ni—O4	90.95 (5)	C15—C16—C21	111.11 (13)
N2^i—Ni—O4	87.28 (5)	O21—C21—N1	124.60 (14)
N2—Ni—O4	92.72 (5)	O21—C21—C16	122.19 (14)
O4—Ni—O4^i	180.00	N1—C21—C16	113.20 (13)
O2—S1—O1	114.15 (8)	N2—C31—C32	123.45 (15)
O2—S1—N1	111.84 (7)	N2—C31—H31	118.3
O1—S1—N1	110.91 (7)	C32—C31—H31	118.3
O2—S1—C15	110.26 (7)	C31—C32—C33	118.82 (16)
O1—S1—C15	111.37 (7)	C31—C32—H32	120.6
N1—S1—C15	97.06 (7)	C33—C32—H32	120.6
C21—N1—S1	111.72 (10)	C34—C33—C32	117.92 (16)
C35—N2—C31	117.50 (13)	C34—C33—H33	121.0
C35—N2—Ni	124.36 (10)	C32—C33—H33	121.0
C31—N2—Ni	118.13 (10)	C33—C34—C35	120.48 (15)
C37—O3—Ni	121.03 (9)	C33—C34—H34	119.8
C37—O3—H3	112.3 (19)	C35—C34—H34	119.8
Ni—O3—H3	114.3 (19)	N2—C35—C34	121.77 (15)
Ni—O4—H4A	112.5 (17)	N2—C35—C36	117.34 (13)
Ni—O4—H4B	113.0 (17)	C34—C35—C36	120.81 (14)
H4A—O4—H4B	107 (2)	C35—C36—C37	112.35 (13)
C16—C11—C12	117.92 (15)	C35—C36—H36A	109.1
C16—C11—H11	121.0	C37—C36—H36A	109.1
C12—C11—H11	121.0	C35—C36—H36B	109.1
C11—C12—C13	120.83 (15)	C37—C36—H36B	109.1
C11—C12—H12	119.6	H36A—C36—H36B	107.9
C13—C12—H12	119.6	O3—C37—C36	109.10 (13)
C14—C13—C12	121.47 (15)	O3—C37—H37A	109.9
C14—C13—H13	119.3	C36—C37—H37A	109.9
C12—C13—H13	119.3	O3—C37—H37B	109.9
C15—C14—C13	116.78 (15)	C36—C37—H37B	109.9
C15—C14—H14	121.6	H37A—C37—H37B	108.3
C13—C14—H14	121.6
O2—S1—N1—C21	−114.55 (12)	C12—C11—C16—C21	179.61 (16)
O1—S1—N1—C21	116.77 (12)	C14—C15—C16—C11	0.7 (2)
C15—S1—N1—C21	0.64 (13)	S1—C15—C16—C11	−178.36 (13)
O3^i—Ni—N2—C35	150.16 (13)	C14—C15—C16—C21	−179.56 (15)
O3—Ni—N2—C35	−29.84 (13)	S1—C15—C16—C21	1.36 (16)
O4—Ni—N2—C35	61.14 (13)	S1—N1—C21—O21	−179.22 (13)
O4^i—Ni—N2—C35	−118.86 (13)	S1—N1—C21—C16	0.09 (17)
O3^i—Ni—N2—C31	−30.22 (12)	C11—C16—C21—O21	−2.0 (3)
O3—Ni—N2—C31	149.78 (12)	C15—C16—C21—O21	178.30 (15)
O4—Ni—N2—C31	−119.24 (12)	C11—C16—C21—N1	178.67 (16)
O4^i—Ni—N2—C31	60.76 (12)	C15—C16—C21—N1	−1.02 (19)
N2^i—Ni—O3—C37	−177.05 (12)	C35—N2—C31—C32	−1.5 (2)
N2—Ni—O3—C37	2.95 (12)	Ni—N2—C31—C32	178.88 (13)
O4—Ni—O3—C37	−89.77 (12)	N2—C31—C32—C33	−0.5 (3)
O4^i—Ni—O3—C37	90.23 (12)	C31—C32—C33—C34	1.1 (3)
C16—C11—C12—C13	0.3 (3)	C32—C33—C34—C35	0.3 (3)
C11—C12—C13—C14	0.2 (3)	C31—N2—C35—C34	2.9 (2)
C12—C13—C14—C15	−0.3 (3)	Ni—N2—C35—C34	−177.47 (12)
C13—C14—C15—C16	−0.2 (2)	C31—N2—C35—C36	−173.69 (15)
C13—C14—C15—S1	178.63 (13)	Ni—N2—C35—C36	5.9 (2)
O2—S1—C15—C14	−63.73 (17)	C33—C34—C35—N2	−2.4 (3)
O1—S1—C15—C14	64.06 (17)	C33—C34—C35—C36	174.09 (16)
N1—S1—C15—C14	179.83 (16)	N2—C35—C36—C37	52.9 (2)
O2—S1—C15—C16	115.24 (11)	C34—C35—C36—C37	−123.75 (16)
O1—S1—C15—C16	−116.97 (11)	Ni—O3—C37—C36	43.05 (17)
N1—S1—C15—C16	−1.20 (12)	C35—C36—C37—O3	−79.29 (17)
C12—C11—C16—C15	−0.7 (2)

Symmetry code: (i) −x, −y+1, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O21^i	0.81 (3)	1.85 (3)	2.6515 (16)	172 (3)
O4—H4A···O1^ii	0.76 (2)	2.07 (2)	2.8325 (17)	175 (2)
C32—H32···O21^iii	0.95	2.64	3.357 (2)	133
C33—H33···O2^iv	0.95	2.45	3.342 (2)	156

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