Di­aqua­bis(N,N-diethyl­nicotin­amide)­bis(4-nitro­benzoato)­zinc(II)

The title compound, [Zn(C₇H₄NO₄)₂(C₁₀H₁₄N₂O)₂(H₂O)₂], crystallizes as centrosymmetric mononuclear mol­ecules with octahedrally coordinated zinc, all pairs of equivalent ligands being mutually trans. Intramolecular hydrogen bonding links each aqua ligand with an uncoordinated carboxyl­ate O atom, and intermolecular hydrogen bonding between aqua ligands and the carbonyl O atoms of N,N-diethyl­nicotin­amide ligands link the mol­ecules together into chains.

Key indicators

• Single-crystal X-ray study
• T = 160 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.026
• wR factor = 0.068
• Data-to-parameter ratio = 12.8

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

General Notes



ABSTM_02  When printed, the submitted absorption T values will be replaced
          by the scaled T values. Since the ratio of scaled T's is
          identical to the ratio of reported T values, the scaling does
          not imply a change to the absorption corrections used in the
          study.
          Ratio of Tmax expected/reported      0.905
          Tmax scaled      0.868 Tmin scaled      0.743

---

S1. Comment

The title compound, (I), was prepared as part of a series of studies of the coordination chemistry of the ligand N,N-diethylnicotinamide (DENA). It has a molecular structure (Fig. 1) very similar to that of the corresponding complex in which 2-hydroxybenzoate (salicylate) replaces 4-nitrobenzoate, reported in a parallel publication (Necefoglu et al., 2001). Coordination of zinc is close to regular octahedral, with all pairs of equivalent ligands mutually trans across a crystallographic inversion centre.

Each aqua ligand is involved as donor in two hydrogen bonds. One of these is intramolecular, to an uncoordinated carboxylate oxygen atom, lengthening the C═O nominal double bond to almost the same as C—O for the coordinated O atom. The other is intermolecular, linking the molecules together in chains along the a axis.

S2. Experimental

The title compound was prepared by the reaction of 4.34 g (0.01 mol) of [Zn(OH₂)₂(4-O₂NC₆H₄COO)₂] and 2.56 g (0.02 mol) of diethylnicotinamide in 100 ml water. The solution was filtered and set aside for crystallization at ambient temperature for a few days. Suitable colourless crystals were obtained.

S3. Refinement

H atoms were placed geometrically and refined with a riding model (including free rotation about C—C bonds), and with U_iso constrained to be 1.2 (1.5 for methyl groups) times U_eq of the carrier atom, except for aqua ligand H atoms, which were refined freely with individual U_iso.

Computing details

Data collection: DIF4 (Stoe & Cie, 1988); cell refinement: DIF4; data reduction: local programs; program(s) used to solve structure: SHELXTL (Sheldrick, 1997); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and local programs.

Figures

	Fig. 1. The molecular structure of (I) with atom labels and 50% probability ellipsoids for non-H atoms.
	Fig. 2. View of two molecules and the unit-cell outline, showing intramolecular and intermolecular hydrogen bonding as dashed lines.

Diaquabis(N,N-diethylnicotinamide)bis(4-nitrobenzoato)zinc(II)

Crystal data

[Zn(C7H4NO4)2(C10H14N2O)2(H2O)2]	Z = 1
Mr = 790.09	F(000) = 412
Triclinic, P1	Dx = 1.436 Mg m^−3
a = 7.211 (3) Å	Mo Kα radiation, λ = 0.71073 Å
b = 8.588 (4) Å	Cell parameters from 36 reflections
c = 16.515 (7) Å	θ = 10.7–12.5°
α = 96.00 (2)°	µ = 0.74 mm^−1
β = 100.79 (2)°	T = 160 K
γ = 112.09 (3)°	Block, colourless
V = 913.6 (7) Å^3	0.42 × 0.27 × 0.19 mm

Data collection

Stoe-Siemens four-circle diffractometer	2889 reflections with I > 2σ(I)
Radiation source: sealed tube	Rint = 0.020
Graphite monochromator	θmax = 25.0°, θmin = 2.6°
ω/θ scans with on–line profile fitting (Clegg, 1981)	h = −8→8
Absorption correction: ψ scan (XPREP; Sheldrick, 1997)	k = −10→10
Tmin = 0.821, Tmax = 0.959	l = −19→19
6298 measured reflections	5 standard reflections every 60 min
3214 independent reflections	intensity decay: 1%

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) = 0.068	H atoms treated by a mixture of independent and constrained refinement
S = 1.10	w = 1/[σ^2(Fo^2) + (0.0275P)^2 + 0.4095P] where P = (Fo^2 + 2Fc^2)/3
3214 reflections	(Δ/σ)max < 0.001
251 parameters	Δρmax = 0.33 e Å^−3
0 restraints	Δρmin = −0.26 e Å^−3

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

	x	y	z	Uiso*/Ueq
Zn	0.5000	0.5000	0.5000	0.01697 (9)
O1	0.79004 (19)	0.50312 (18)	0.56174 (8)	0.0227 (3)
H1A	0.813 (4)	0.570 (3)	0.6084 (17)	0.049 (7)*
H1B	0.787 (4)	0.414 (3)	0.5760 (14)	0.039 (7)*
N1	0.6747 (2)	0.71783 (17)	0.45183 (8)	0.0183 (3)
C1	0.6537 (3)	0.8666 (2)	0.46307 (10)	0.0201 (3)
H1	0.5623	0.8779	0.4956	0.024*
C2	0.7599 (3)	1.0046 (2)	0.42920 (11)	0.0220 (4)
H2	0.7413	1.1083	0.4385	0.026*
C3	0.8932 (3)	0.9895 (2)	0.38164 (11)	0.0218 (4)
H3	0.9659	1.0817	0.3570	0.026*
C4	0.9188 (2)	0.8365 (2)	0.37061 (10)	0.0182 (3)
C5	0.8087 (2)	0.7051 (2)	0.40749 (10)	0.0186 (3)
H5	0.8288	0.6018	0.4012	0.022*
C6	1.0807 (3)	0.8142 (2)	0.33073 (10)	0.0199 (4)
O2	1.21846 (19)	0.78446 (16)	0.37503 (8)	0.0270 (3)
N2	1.0770 (2)	0.82976 (18)	0.25073 (9)	0.0229 (3)
C7	0.9084 (3)	0.8481 (2)	0.19266 (11)	0.0297 (4)
H7A	0.9675	0.9476	0.1661	0.036*
H7B	0.8163	0.8717	0.2250	0.036*
C8	0.7817 (4)	0.6905 (3)	0.12447 (15)	0.0529 (6)
H8A	0.6644	0.7059	0.0911	0.079*
H8B	0.7306	0.5899	0.1503	0.079*
H8C	0.8681	0.6741	0.0880	0.079*
C9	1.2497 (3)	0.8191 (2)	0.21772 (12)	0.0294 (4)
H9A	1.3808	0.8874	0.2603	0.035*
H9B	1.2549	0.8712	0.1670	0.035*
C10	1.2343 (4)	0.6371 (3)	0.19520 (15)	0.0405 (5)
H10A	1.3550	0.6402	0.1751	0.061*
H10B	1.1084	0.5698	0.1510	0.061*
H10C	1.2295	0.5844	0.2450	0.061*
O3	0.50606 (18)	0.33955 (14)	0.39517 (7)	0.0205 (3)
C11	0.3897 (3)	0.3038 (2)	0.32227 (10)	0.0184 (3)
O4	0.20852 (18)	0.29485 (15)	0.30447 (7)	0.0240 (3)
C12	0.4800 (3)	0.2719 (2)	0.24946 (10)	0.0191 (3)
C13	0.6763 (3)	0.2716 (2)	0.26350 (11)	0.0207 (4)
H13	0.7549	0.2913	0.3194	0.025*
C14	0.7586 (3)	0.2426 (2)	0.19654 (11)	0.0230 (4)
H14	0.8922	0.2417	0.2057	0.028*
C15	0.6390 (3)	0.2151 (2)	0.11612 (11)	0.0232 (4)
C16	0.4439 (3)	0.2160 (2)	0.09983 (11)	0.0244 (4)
H16	0.3664	0.1974	0.0438	0.029*
C17	0.3649 (3)	0.2446 (2)	0.16737 (11)	0.0223 (4)
H17	0.2314	0.2457	0.1578	0.027*
N3	0.7240 (2)	0.1864 (2)	0.04415 (9)	0.0288 (4)
O5	0.8860 (2)	0.1667 (2)	0.05764 (9)	0.0508 (4)
O6	0.6269 (2)	0.1804 (2)	−0.02622 (8)	0.0408 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zn	0.01512 (15)	0.01988 (15)	0.01763 (15)	0.00705 (11)	0.00675 (10)	0.00605 (10)
O1	0.0206 (7)	0.0264 (7)	0.0252 (7)	0.0128 (5)	0.0069 (5)	0.0072 (6)
N1	0.0146 (7)	0.0212 (7)	0.0200 (7)	0.0070 (6)	0.0058 (6)	0.0062 (5)
C1	0.0177 (8)	0.0247 (8)	0.0211 (8)	0.0106 (7)	0.0075 (7)	0.0049 (7)
C2	0.0221 (9)	0.0217 (8)	0.0266 (9)	0.0122 (7)	0.0080 (7)	0.0062 (7)
C3	0.0200 (9)	0.0220 (8)	0.0246 (9)	0.0074 (7)	0.0079 (7)	0.0096 (7)
C4	0.0149 (8)	0.0216 (8)	0.0180 (8)	0.0071 (7)	0.0040 (6)	0.0051 (6)
C5	0.0173 (8)	0.0199 (8)	0.0202 (8)	0.0085 (7)	0.0056 (7)	0.0046 (6)
C6	0.0175 (8)	0.0176 (8)	0.0258 (9)	0.0064 (7)	0.0080 (7)	0.0064 (7)
O2	0.0214 (6)	0.0356 (7)	0.0317 (7)	0.0163 (6)	0.0106 (5)	0.0132 (6)
N2	0.0256 (8)	0.0261 (8)	0.0258 (8)	0.0148 (6)	0.0144 (6)	0.0108 (6)
C7	0.0378 (11)	0.0367 (10)	0.0255 (9)	0.0227 (9)	0.0121 (8)	0.0146 (8)
C8	0.0507 (15)	0.0595 (15)	0.0454 (13)	0.0287 (13)	−0.0042 (11)	0.0016 (11)
C9	0.0346 (11)	0.0293 (10)	0.0364 (10)	0.0162 (8)	0.0253 (9)	0.0144 (8)
C10	0.0518 (14)	0.0359 (11)	0.0529 (13)	0.0267 (10)	0.0336 (11)	0.0163 (10)
O3	0.0213 (6)	0.0238 (6)	0.0182 (6)	0.0099 (5)	0.0072 (5)	0.0044 (5)
C11	0.0203 (9)	0.0140 (7)	0.0209 (8)	0.0050 (6)	0.0081 (7)	0.0059 (6)
O4	0.0171 (6)	0.0303 (7)	0.0246 (6)	0.0087 (5)	0.0073 (5)	0.0042 (5)
C12	0.0198 (8)	0.0157 (8)	0.0214 (8)	0.0052 (7)	0.0078 (7)	0.0044 (6)
C13	0.0199 (9)	0.0221 (8)	0.0199 (8)	0.0087 (7)	0.0041 (7)	0.0040 (7)
C14	0.0188 (9)	0.0258 (9)	0.0255 (9)	0.0102 (7)	0.0063 (7)	0.0037 (7)
C15	0.0255 (9)	0.0249 (9)	0.0214 (9)	0.0107 (7)	0.0102 (7)	0.0035 (7)
C16	0.0236 (9)	0.0302 (9)	0.0191 (8)	0.0118 (8)	0.0034 (7)	0.0033 (7)
C17	0.0178 (8)	0.0256 (9)	0.0235 (9)	0.0091 (7)	0.0045 (7)	0.0045 (7)
N3	0.0275 (9)	0.0370 (9)	0.0237 (8)	0.0137 (7)	0.0104 (7)	0.0032 (7)
O5	0.0353 (9)	0.0909 (13)	0.0347 (8)	0.0367 (9)	0.0119 (7)	−0.0008 (8)
O6	0.0475 (9)	0.0642 (10)	0.0221 (7)	0.0314 (8)	0.0146 (6)	0.0116 (7)

Geometric parameters (Å, º)

Zn—O1^i	2.1373 (15)	C8—H8A	0.980
Zn—O1	2.1373 (15)	C8—H8B	0.980
Zn—O3^i	2.1149 (14)	C8—H8C	0.980
Zn—O3	2.1149 (14)	C9—C10	1.525 (3)
Zn—N1	2.1527 (16)	C9—H9A	0.990
Zn—N1^i	2.1527 (16)	C9—H9B	0.990
O1—H1A	0.86 (3)	C10—H10A	0.980
O1—H1B	0.81 (3)	C10—H10B	0.980
N1—C1	1.340 (2)	C10—H10C	0.980
N1—C5	1.345 (2)	C11—O3	1.264 (2)
C1—C2	1.386 (2)	C11—O4	1.255 (2)
C1—H1	0.950	C11—C12	1.518 (2)
C2—C3	1.383 (2)	C12—C13	1.392 (3)
C2—H2	0.950	C12—C17	1.395 (2)
C3—C4	1.392 (2)	C13—C14	1.392 (2)
C3—H3	0.950	C13—H13	0.950
C4—C5	1.387 (2)	C14—C15	1.384 (3)
C4—C6	1.504 (2)	C14—H14	0.950
C5—H5	0.950	C15—C16	1.385 (3)
C6—O2	1.243 (2)	C15—N3	1.474 (2)
C6—N2	1.338 (2)	C16—C17	1.384 (2)
N2—C7	1.470 (2)	C16—H16	0.950
N2—C9	1.479 (2)	C17—H17	0.950
C7—C8	1.517 (3)	N3—O6	1.225 (2)
C7—H7A	0.990	N3—O5	1.225 (2)
C7—H7B	0.990
O3^i—Zn—O3	180.0	C8—C7—H7B	108.9
O3^i—Zn—O1^i	87.54 (6)	H7A—C7—H7B	107.8
O3—Zn—O1^i	92.46 (6)	C7—C8—H8A	109.5
O3^i—Zn—O1	92.46 (6)	C7—C8—H8B	109.5
O3—Zn—O1	87.54 (6)	H8A—C8—H8B	109.5
O1^i—Zn—O1	180.0	C7—C8—H8C	109.5
O3^i—Zn—N1	91.46 (6)	H8A—C8—H8C	109.5
O3—Zn—N1	88.54 (6)	H8B—C8—H8C	109.5
O1^i—Zn—N1	93.29 (6)	N2—C9—C10	114.03 (16)
O1—Zn—N1	86.71 (6)	N2—C9—H9A	108.7
O3^i—Zn—N1^i	88.54 (6)	C10—C9—H9A	108.7
O3—Zn—N1^i	91.46 (6)	N2—C9—H9B	108.7
O1^i—Zn—N1^i	86.71 (6)	C10—C9—H9B	108.7
O1—Zn—N1^i	93.29 (6)	H9A—C9—H9B	107.6
N1—Zn—N1^i	180.0	C9—C10—H10A	109.5
Zn—O1—H1A	99.5 (17)	C9—C10—H10B	109.5
Zn—O1—H1B	116.0 (17)	H10A—C10—H10B	109.5
H1A—O1—H1B	103 (2)	C9—C10—H10C	109.5
C1—N1—C5	118.01 (14)	H10A—C10—H10C	109.5
C1—N1—Zn	122.64 (11)	H10B—C10—H10C	109.5
C5—N1—Zn	119.34 (11)	C11—O3—Zn	125.41 (11)
N1—C1—C2	122.72 (16)	O4—C11—O3	126.30 (15)
N1—C1—H1	118.6	O4—C11—C12	117.12 (15)
C2—C1—H1	118.6	O3—C11—C12	116.58 (15)
C3—C2—C1	119.11 (16)	C13—C12—C17	119.74 (16)
C3—C2—H2	120.4	C13—C12—C11	120.96 (15)
C1—C2—H2	120.4	C17—C12—C11	119.29 (16)
C2—C3—C4	118.71 (15)	C14—C13—C12	120.75 (16)
C2—C3—H3	120.6	C14—C13—H13	119.6
C4—C3—H3	120.6	C12—C13—H13	119.6
C5—C4—C3	118.59 (16)	C15—C14—C13	117.69 (17)
C5—C4—C6	117.71 (15)	C15—C14—H14	121.2
C3—C4—C6	123.16 (15)	C13—C14—H14	121.2
N1—C5—C4	122.82 (15)	C14—C15—C16	123.11 (16)
N1—C5—H5	118.6	C14—C15—N3	118.69 (16)
C4—C5—H5	118.6	C16—C15—N3	118.18 (16)
O2—C6—N2	121.81 (16)	C17—C16—C15	118.22 (16)
O2—C6—C4	117.72 (15)	C17—C16—H16	120.9
N2—C6—C4	120.45 (15)	C15—C16—H16	120.9
C6—N2—C7	124.48 (15)	C16—C17—C12	120.48 (17)
C6—N2—C9	117.40 (15)	C16—C17—H17	119.8
C7—N2—C9	118.04 (15)	C12—C17—H17	119.8
N2—C7—C8	113.16 (17)	O6—N3—O5	123.39 (16)
N2—C7—H7A	108.9	O6—N3—C15	118.20 (16)
C8—C7—H7A	108.9	O5—N3—C15	118.39 (15)
N2—C7—H7B	108.9

Symmetry code: (i) −x+1, −y+1, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1A···O4^i	0.86 (3)	1.82 (3)	2.659 (2)	164 (3)
O1—H1B···O2^ii	0.81 (3)	1.95 (3)	2.765 (2)	173 (2)

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