Bis[4-(dimethyl­amino)pyridine-κN]bis­(salicylato-κO)zinc(II)

The reaction of Zn(CH₃COO)₂ with 4-(dimethyl­amino)­pyridine (DMAP) and salicylic acid in a 1:2:2 molar ratio affords the title complex, [Zn(C₇H₅O₃)₂(C₇H₁₀N₂)₂]. The Zn^II atom resides on a twofold rotation axis and is tetra­hedrally coordinated by two DMAP ligands and two salicylate anions in a distorted tetra­hedral geometry.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.042
• wR factor = 0.107
• Data-to-parameter ratio = 13.7

checkCIF/PLATON results

No syntax errors found



Alert level A
DIFF020_ALERT_1_A  _diffrn_standards_interval_count and
            _diffrn_standards_interval_time are missing. Number of measurements
            between standards or time (min) between standards.
DIFF022_ALERT_1_A  _diffrn_standards_decay_% is missing
            Percentage decrease in standards intensity.

Alert level B
PLAT230_ALERT_2_B Hirshfeld Test Diff for    O2     -   C7      ..      13.66 su
PLAT232_ALERT_2_B Hirshfeld Test Diff (M-X)  Zn1    -   O1      ..      10.48 su
PLAT241_ALERT_2_B Check High      Ueq as Compared to Neighbors for         O2
PLAT242_ALERT_2_B Check Low       Ueq as Compared to Neighbors for        Zn1

Alert level C
PLAT094_ALERT_2_C Ratio of Maximum / Minimum Residual Density ....       2.01
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .......          ?
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for         O1
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C1
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C2

Alert level G
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K
PLAT794_ALERT_5_G Check Predicted Bond Valency for Zn1         (2)       1.76

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

   4 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   8 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
   1 ALERT type 5 Informative message, check

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S1. Comment

In preparing metal complexes, carboxylate and pyridine ligands have been frequently employed (Wang et al., 2006). Although 4-dimethylaminopyridine (DMAP) has good coordination ability, there are few reports on its complexes (Tyrra et al., 2003) except a lot of reports on its nucleophilic catalytic properties (Fu, 2000). We report here the synthesis and crystal structure of a new DMAP mononuclear zinc(II) complex.

The asymmetric unit contains one-half molecule of [Zn(C₇H₁₀N₂)₂(C₇H₅O₃)₂] (Fig. 1). The Zn atom resides on a site of 2-fold symmetry and is in a tetrahedral environment with the Zn1—O1 and Zn1—N1 bond lengths 2.002 (3) and 2.028 (2) Å, respectively. The DMAP ligands coordinate to zinc through the pyridyl N atoms while the salicylate anions bond through a single carboxyl O atom. The non-coordinated carboxyl O atom is involved in an intramolecular hydrogen bond to the non-coordinated hydroxyl group (Table 1).

Related literature

For related literature, see: Fu (2000); Tyrra et al. (2003); Wang et al. (2006).

S2. Experimental

An aqueous solution (10 ml) containing salicylic acid (0.1381 g, 1.0 mmol) and Zn(CH₃COO)₂.2H₂O (0.1098 g, 0.5 mmol) was mixed and refluxed for 1 h. Then another ethanol solution (5 ml) of DMAP (0.1222 g, 1 mmol) was added dropwise into the above solution. The resulted mixture was refluxed for 4 h. The solution was filtered after cooling to room temperature. Colorless single crystals suitable for X-ray diffraction were obtained from the filtrate after 4 d.

S3. Refinement

The H atoms were placed in geometrically idealized positions and constrained to ride on their parent atoms with C—H distances = 0.93Å and U_iso(H) = 1.2U_eq(C), O—H distance = 0.8156 Å and U_iso(H) = 1.2U_eq(O)

Computing details

Data collection: APEX2 (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Sheldrick, 2000); software used to prepare material for publication: SHELXTL.

Figures

Fig. 1. The molecular structure of the title compound, with displacement ellipsoids drawn at the 30% probability level.

Bis[4-(dimethylamino)pyridine-κN]bis(salicylato-κO)zinc(II)

Crystal data

[Zn(C7H5O3)2(C7H10N2)2]	F(000) = 1216
Mr = 583.93	Dx = 1.404 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 19.961 (2) Å	Cell parameters from 2692 reflections
b = 7.5009 (9) Å	θ = 2.2–23.7°
c = 18.488 (2) Å	µ = 0.94 mm^−1
β = 93.583 (8)°	T = 293 K
V = 2762.7 (5) Å^3	Block, colourless
Z = 4	0.30 × 0.20 × 0.20 mm

Data collection

Bruker SMART APEXII diffractometer	2032 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.020
Graphite monochromator	θmax = 25.0°, θmin = 2.2°
φ and ω scans	h = −23→20
6850 measured reflections	k = −8→8
2419 independent reflections	l = −21→21

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)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.107	H-atom parameters constrained
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0463P)^2 + 3.8555P] where P = (Fo^2 + 2Fc^2)/3
2419 reflections	(Δ/σ)max < 0.001
177 parameters	Δρmax = 0.58 e Å^−3
0 restraints	Δρmin = −0.29 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
Zn1	0.0000	0.58617 (6)	0.2500	0.05591 (19)
C1	0.15627 (14)	0.2514 (4)	0.31399 (16)	0.0536 (7)
C2	0.19655 (18)	0.2440 (5)	0.37794 (17)	0.0682 (9)
C3	0.24291 (17)	0.1075 (5)	0.38911 (19)	0.0709 (9)
H3	0.2699	0.1028	0.4319	0.085*
C4	0.24888 (16)	−0.0184 (5)	0.3378 (2)	0.0734 (9)
H4	0.2803	−0.1091	0.3456	0.088*
C5	0.20952 (17)	−0.0147 (5)	0.2746 (2)	0.0783 (10)
H5	0.2138	−0.1026	0.2397	0.094*
C6	0.16372 (15)	0.1199 (4)	0.26335 (18)	0.0642 (8)
H6	0.1370	0.1223	0.2203	0.077*
C7	0.10649 (19)	0.3990 (5)	0.3030 (3)	0.0789 (10)
C8	−0.01148 (16)	0.9075 (4)	0.15743 (17)	0.0649 (8)
H8	−0.0528	0.9157	0.1778	0.078*
C9	0.00609 (16)	1.0410 (4)	0.11356 (16)	0.0625 (8)
H9	−0.0228	1.1372	0.1051	0.075*
C10	0.06755 (15)	1.0362 (4)	0.08056 (14)	0.0532 (7)
C11	0.10614 (15)	0.8820 (4)	0.09559 (16)	0.0566 (7)
H11	0.1466	0.8665	0.0740	0.068*
C12	0.08467 (14)	0.7553 (4)	0.14149 (15)	0.0543 (7)
H12	0.1122	0.6570	0.1510	0.065*
C13	0.0484 (2)	1.3291 (5)	0.0261 (2)	0.0835 (11)
H13A	0.0519	1.4051	0.0670	0.100*
H13B	0.0638	1.3916	−0.0158	0.100*
H13C	0.0013	1.2988	0.0151	0.100*
C14	0.1501 (2)	1.1575 (6)	0.0028 (2)	0.0967 (13)
H14A	0.1476	1.0874	−0.0415	0.116*
H14B	0.1679	1.2744	−0.0092	0.116*
H14C	0.1871	1.1006	0.0343	0.116*
N1	0.02661 (12)	0.7628 (3)	0.17384 (12)	0.0555 (6)
N2	0.08845 (14)	1.1690 (4)	0.03907 (14)	0.0683 (7)
O1	0.07388 (13)	0.4073 (3)	0.24406 (18)	0.0930 (8)
O2	0.09803 (19)	0.5057 (5)	0.3525 (2)	0.1405 (14)
O3	0.1925 (2)	0.3681 (5)	0.43048 (16)	0.1324 (13)
H3A	0.1616	0.4356	0.4193	0.159*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zn1	0.0570 (3)	0.0546 (3)	0.0565 (3)	0.000	0.0065 (2)	0.000
C1	0.0468 (15)	0.0503 (17)	0.0651 (18)	−0.0040 (13)	0.0138 (13)	0.0031 (14)
C2	0.079 (2)	0.069 (2)	0.0574 (19)	−0.0070 (8)	0.0153 (16)	−0.0098 (16)
C3	0.065 (2)	0.083 (2)	0.063 (2)	−0.0058 (18)	−0.0032 (15)	0.0084 (18)
C4	0.0552 (19)	0.071 (2)	0.094 (3)	0.0100 (17)	0.0049 (18)	0.003 (2)
C5	0.070 (2)	0.075 (2)	0.089 (3)	0.0123 (19)	0.0035 (19)	−0.027 (2)
C6	0.0551 (18)	0.075 (2)	0.0624 (18)	−0.0047 (16)	0.0005 (14)	−0.0051 (16)
C7	0.064 (2)	0.065 (2)	0.109 (3)	0.0015 (18)	0.017 (2)	0.016 (2)
C8	0.0542 (17)	0.075 (2)	0.0675 (19)	0.0148 (16)	0.0160 (14)	0.0046 (17)
C9	0.0636 (19)	0.0623 (19)	0.0620 (19)	0.0193 (15)	0.0068 (15)	0.0026 (15)
C10	0.0603 (17)	0.0541 (17)	0.0449 (15)	0.0057 (13)	0.0027 (13)	−0.0044 (13)
C11	0.0536 (16)	0.0557 (18)	0.0617 (17)	0.0072 (13)	0.0126 (13)	0.0016 (14)
C12	0.0521 (16)	0.0525 (17)	0.0583 (17)	0.0098 (13)	0.0047 (13)	−0.0018 (13)
C13	0.108 (3)	0.061 (2)	0.083 (2)	0.018 (2)	0.011 (2)	0.0116 (19)
C14	0.097 (3)	0.086 (3)	0.111 (3)	0.005 (2)	0.039 (2)	0.029 (2)
N1	0.0513 (13)	0.0581 (15)	0.0575 (14)	0.0068 (11)	0.0074 (11)	0.0015 (11)
N2	0.0818 (18)	0.0587 (16)	0.0663 (16)	0.0107 (14)	0.0193 (14)	0.0111 (13)
O1	0.0681 (15)	0.0830 (18)	0.127 (2)	0.0055 (13)	−0.0008 (16)	0.0269 (16)
O2	0.159 (3)	0.104 (2)	0.081 (3)	0.043 (3)	0.006 (3)	−0.030 (2)
O3	0.187 (4)	0.121 (3)	0.087 (2)	0.036 (2)	−0.008 (2)	−0.0484 (19)

Geometric parameters (Å, º)

Zn1—O1^i	2.002 (3)	C8—C9	1.349 (4)
Zn1—O1	2.002 (3)	C8—H8	0.9300
Zn1—N1	2.028 (2)	C9—C10	1.404 (4)
Zn1—N1^i	2.028 (2)	C9—H9	0.9300
C1—C6	1.375 (4)	C10—N2	1.340 (4)
C1—C2	1.389 (4)	C10—C11	1.408 (4)
C1—C7	1.493 (5)	C11—C12	1.361 (4)
C2—O3	1.351 (4)	C11—H11	0.9300
C2—C3	1.387 (5)	C12—N1	1.338 (3)
C3—C4	1.349 (5)	C12—H12	0.9300
C3—H3	0.9300	C13—N2	1.454 (4)
C4—C5	1.367 (5)	C13—H13A	0.9460
C4—H4	0.9300	C13—H13B	0.9719
C5—C6	1.369 (5)	C13—H13C	0.9775
C5—H5	0.9300	C14—N2	1.440 (4)
C6—H6	0.9300	C14—H14A	0.9714
C7—O1	1.235 (5)	C14—H14B	0.9769
C7—O2	1.236 (5)	C14—H14C	1.0073
C8—N1	1.349 (4)	O3—H3A	0.8156
O1^i—Zn1—O1	95.82 (15)	C8—C9—H9	119.7
O1^i—Zn1—N1	134.57 (12)	C10—C9—H9	119.7
O1—Zn1—N1	100.02 (10)	N2—C10—C9	122.8 (3)
O1^i—Zn1—N1^i	100.02 (10)	N2—C10—C11	122.5 (3)
O1—Zn1—N1^i	134.57 (12)	C9—C10—C11	114.7 (3)
N1—Zn1—N1^i	98.43 (14)	C12—C11—C10	120.5 (3)
C6—C1—C2	118.0 (3)	C12—C11—H11	119.8
C6—C1—C7	122.6 (3)	C10—C11—H11	119.8
C2—C1—C7	119.4 (3)	N1—C12—C11	124.4 (3)
O3—C2—C3	118.1 (3)	N1—C12—H12	117.8
O3—C2—C1	121.8 (3)	C11—C12—H12	117.8
C3—C2—C1	120.1 (3)	N2—C13—H13A	110.7
C4—C3—C2	120.0 (3)	N2—C13—H13B	109.4
C4—C3—H3	120.0	H13A—C13—H13B	109.7
C2—C3—H3	120.0	N2—C13—H13C	110.7
C3—C4—C5	121.1 (3)	H13A—C13—H13C	109.2
C3—C4—H4	119.5	H13B—C13—H13C	107.1
C5—C4—H4	119.5	N2—C14—H14A	115.1
C4—C5—C6	119.1 (3)	N2—C14—H14B	112.7
C4—C5—H5	120.4	H14A—C14—H14B	107.2
C6—C5—H5	120.4	N2—C14—H14C	111.9
C5—C6—C1	121.7 (3)	H14A—C14—H14C	104.8
C5—C6—H6	119.1	H14B—C14—H14C	104.4
C1—C6—H6	119.1	C12—N1—C8	115.2 (3)
O1—C7—O2	122.1 (4)	C12—N1—Zn1	123.7 (2)
O1—C7—C1	117.9 (4)	C8—N1—Zn1	120.88 (19)
O2—C7—C1	120.0 (4)	C10—N2—C14	121.9 (3)
N1—C8—C9	124.6 (3)	C10—N2—C13	121.4 (3)
N1—C8—H8	117.7	C14—N2—C13	116.7 (3)
C9—C8—H8	117.7	C7—O1—Zn1	109.6 (3)
C8—C9—C10	120.6 (3)	C2—O3—H3A	108.9

Symmetry code: (i) −x, y, −z+1/2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···O2	0.82	1.79	2.522 (5)	148