Diacetatobis(2-amino­benzothia­zole-κN)cobalt(II)

The title complex, [Co(C₂H₃O₂)₂(C₇H₆N₂S)₂], contains a Co centre with a slightly distorted tetra­hedral coordination geometry, involving two acetate ligands and two N atoms from the thia­zole moiety [Co—O = 2.0025 (14) and 1.9953 (16) Å, and Co—N = 2.0524 (18) and 2.0568 (18) Å]. The inter­planar angle between the two benzothia­zole moieties is 77.86 (3)°. The amine groups, acting as donors, participate in intra- and inter­molecular N—H...O hydrogen bonds, with N...O distances in the range 2.806 (2)–2.857 (2) Å.

S1. Comment

Small and simple heterocyclic structures often exhibit complex biological properties. Substituted benzothiazoles show antitumour (Goldfarb et al., 1999), anti-infective and antifungal (Sener et al., 2000), and antihelmintic activities (Nadkarn et al., 2000). Bis(benzothiazole) compounds have been studied as potential mimics for metalloproteins (Thompson et al., 1982). It is well known that N and S atoms play a key role in the coordination of metals at the active sites of numerous metallobiomolecules (Karlin & Zubieta, 1983). The structures of many metal complexes of 2-amino-1,3-thiazole derivatives, where the metal is directly bound to the ligand, are known, and these complexes include most of the first-row transition metals (i.e. Mn–Zn). In all but a few cases, the thiazole moities bind to the metal via endocylic N atoms (Lynch & Duckhouse, 2001; Usman et al., 2003). We report here the X-ray crystal structure of the title compound, (I).

In the molecular structure of (I) (Fig.1), the two benzothiazole moieties form a dihedral angle of 77.86 (3)°. It is noteworthy that the two amine groups are not both located on the same side, because of the steric hindrance. Both benzothiazole moieties are nearly planar, the largest deviation from the plane being that of atom C2 [−0.026 (1) Å]. The cobalt centre, coordinated by two endocylic N atoms from the thiazole moieties and two acetate ligands, –CoNCN– and –CoOCC, adopts a syn-periplanar and an anti-periplanar conformation, respectively. This CoN₂O₂ coordination forms a slightly distorted tetrahedral geometry, the angles around the Co atom ranging from 100.22 (7) to 128.90 (7)°. The bond lengths and angles in (I) are shown in Table 1. The C1—N1, C1—N2, C8—N3 and C8—N4 bonds are somewhat shorter than the C2—N1 and C9—N3 bonds, as a result of pronounced delocalization in the –N—C═N– fragment of the 2-aminobenzothiazole ring. The amine groups of both thiazole ligands are hydrogen bonded to the O atoms of the acetate ligands by intra- and intermolecular hydrogen bonds (Table 2). The N2—H2B···O2 hydrogen bonds interconnect the molecules into chains along the a direction, and these are further interconnected into a three-dimensional network by N4—H4B···O4 hydrogen bonds (Fig. 2).

S2. Experimental

An ethanol solution of 2-aminobenzothiazole (4 mmol in 10 ml of ethanol) was added dropwise to Co(CH₃COO)₂·6H₂O (2 mmol in 5 ml of ethanol) with stirring. The colour of the solution changed immediately to violet. The mixture was refluxed for 2 h and the resulting solution was kept at room temperature. After several days, violet crystals were obtained and dried under vacuum.

S3. Refinement

All H atoms were placed in calculated positions, with C—H distances of 0.93 and 0.96 Å, and N—H distances of 0.86 Å. The U_iso(H) values were constrained to be 1.2 (1.5 for methyl groups) times U_eq of the carrier atom.

Computing details

Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA; data reduction: X-RED32 (Stoe & Cie, 2002); program(s) used to solve structure: SHELX86 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures

	Fig. 1. : An ORTEP-3 (Farrugia, 1997) drawing of title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as small spheres of arbitrary radii.
	Fig. 2. : A view of the hydrogen-bonding interactions in (I). For clarity, H atoms bonded to C atoms have been omitted. Displacement ellipsoids are drawn at the 30% probability level and hydrogen bonds are shown as dashed lines.

Diacetatobis(2-aminobenzothiazole-κN)cobalt(II)

Crystal data

[Co(C2H3O2)2(C7H6N2S)2]	F(000) = 980
Mr = 477.43	Dx = 1.563 Mg m^−3
Orthorhombic, Pna21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2n	Cell parameters from 22768 reflections
a = 8.3049 (4) Å	θ = 1.5–26.2°
b = 27.1833 (16) Å	µ = 1.09 mm^−1
c = 8.9868 (5) Å	T = 100 K
V = 2028.81 (19) Å^3	Prism, violet
Z = 4	0.29 × 0.18 × 0.11 mm

Data collection

Stoe IPDS-II diffractometer	3861 independent reflections
Radiation source: fine-focus sealed tube	3697 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.054
Detector resolution: 6.67 pixels mm^-1	θmax = 26.1°, θmin = 1.5°
ϕ or ω? scans	h = −10→10
Absorption correction: integration (X-RED32; Stoe & Cie 2002)	k = −33→33
Tmin = 0.613, Tmax = 0.830	l = −9→11
23485 measured reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.025	H-atom parameters constrained
wR(F^2) = 0.063	w = 1/[σ^2(Fo^2) + (0.046P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.04	(Δ/σ)max < 0.001
3861 reflections	Δρmax = 0.22 e Å^−3
264 parameters	Δρmin = −0.50 e Å^−3
1 restraint	Absolute structure: Flack (1983), 1720 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.005 (10)

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
Co1	0.13575 (3)	0.122036 (8)	1.03477 (4)	0.01848 (8)
S1	0.27466 (7)	0.273666 (19)	0.85372 (7)	0.02730 (13)
S2	0.22983 (7)	−0.021294 (18)	0.77564 (7)	0.02657 (13)
O1	−0.10194 (17)	0.10978 (5)	1.0401 (2)	0.0224 (3)
O2	−0.05469 (18)	0.17762 (5)	1.16565 (19)	0.0232 (3)
O3	0.28953 (18)	0.12872 (5)	1.20415 (19)	0.0211 (3)
O4	0.13515 (18)	0.06757 (6)	1.2751 (2)	0.0294 (4)
N1	0.1939 (2)	0.18368 (6)	0.9143 (2)	0.0196 (4)
N2	0.3103 (2)	0.22725 (6)	1.1131 (2)	0.0251 (4)
H2A	0.3032	0.2025	1.1725	0.030*
H2B	0.3512	0.2545	1.1439	0.030*
N3	0.2146 (2)	0.06406 (6)	0.9070 (2)	0.0212 (4)
N4	−0.0177 (2)	0.01509 (6)	0.9285 (3)	0.0286 (4)
H4A	−0.0666	0.0368	0.9815	0.034*
H4B	−0.0650	−0.0121	0.9067	0.034*
C1	0.2585 (2)	0.22337 (7)	0.9743 (3)	0.0210 (4)
C2	0.1520 (2)	0.19150 (8)	0.7663 (3)	0.0214 (4)
C3	0.0762 (3)	0.15796 (8)	0.6729 (3)	0.0255 (5)
H3	0.0510	0.1265	0.7066	0.031*
C4	0.0388 (3)	0.17197 (8)	0.5290 (3)	0.0319 (5)
H4	−0.0116	0.1497	0.4659	0.038*
C5	0.0755 (3)	0.21912 (10)	0.4768 (3)	0.0361 (6)
H5	0.0496	0.2278	0.3796	0.043*
C6	0.1499 (3)	0.25282 (10)	0.5688 (3)	0.0348 (6)
H6	0.1744	0.2842	0.5347	0.042*
C7	0.1874 (3)	0.23885 (9)	0.7131 (3)	0.0272 (5)
C8	0.1304 (2)	0.02359 (8)	0.8803 (3)	0.0222 (5)
C9	0.3672 (2)	0.06120 (8)	0.8395 (3)	0.0220 (4)
C10	0.4843 (3)	0.09785 (8)	0.8408 (3)	0.0253 (5)
H10	0.4655	0.1276	0.8886	0.030*
C11	0.6294 (3)	0.08907 (9)	0.7696 (3)	0.0289 (5)
H11	0.7088	0.1132	0.7706	0.035*
C12	0.6585 (3)	0.04482 (9)	0.6967 (3)	0.0313 (5)
H12	0.7572	0.0397	0.6502	0.038*
C13	0.5427 (3)	0.00831 (9)	0.6924 (3)	0.0286 (5)
H13	0.5611	−0.0211	0.6425	0.034*
C14	0.3974 (3)	0.01707 (8)	0.7651 (3)	0.0232 (4)
C15	−0.1500 (2)	0.14469 (7)	1.1248 (3)	0.0200 (4)
C16	−0.3214 (3)	0.14501 (9)	1.1767 (3)	0.0286 (5)
H16A	−0.3703	0.1759	1.1514	0.043*
H16B	−0.3245	0.1406	1.2826	0.043*
H16C	−0.3793	0.1187	1.1293	0.043*
C17	0.2499 (2)	0.09582 (7)	1.2998 (3)	0.0217 (5)
C18	0.3489 (3)	0.09268 (10)	1.4375 (3)	0.0337 (6)
H18A	0.4478	0.0758	1.4161	0.051*
H18B	0.2905	0.0749	1.5125	0.051*
H18C	0.3722	0.1252	1.4729	0.051*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Co1	0.02036 (13)	0.01315 (12)	0.02192 (15)	−0.00042 (9)	−0.00199 (12)	−0.00190 (12)
S1	0.0356 (3)	0.0210 (3)	0.0253 (3)	−0.0074 (2)	−0.0037 (2)	0.0063 (2)
S2	0.0343 (3)	0.0167 (2)	0.0286 (3)	0.0035 (2)	−0.0024 (3)	−0.0059 (2)
O1	0.0252 (7)	0.0162 (6)	0.0259 (8)	0.0010 (5)	−0.0001 (8)	−0.0016 (8)
O2	0.0249 (8)	0.0190 (7)	0.0257 (9)	−0.0012 (6)	−0.0020 (6)	−0.0026 (6)
O3	0.0235 (7)	0.0168 (7)	0.0229 (8)	0.0007 (5)	−0.0004 (6)	0.0028 (6)
O4	0.0254 (8)	0.0183 (7)	0.0445 (11)	−0.0036 (6)	0.0007 (7)	0.0046 (8)
N1	0.0231 (9)	0.0166 (8)	0.0189 (10)	−0.0011 (6)	0.0000 (7)	−0.0017 (7)
N2	0.0363 (10)	0.0149 (8)	0.0240 (11)	−0.0063 (7)	−0.0065 (9)	0.0011 (8)
N3	0.0229 (9)	0.0179 (8)	0.0227 (10)	−0.0007 (7)	−0.0010 (7)	−0.0022 (7)
N4	0.0277 (9)	0.0189 (8)	0.0392 (13)	−0.0059 (7)	0.0011 (9)	−0.0086 (8)
C1	0.0228 (10)	0.0168 (9)	0.0235 (12)	−0.0001 (8)	0.0009 (9)	−0.0009 (8)
C2	0.0231 (10)	0.0207 (10)	0.0203 (12)	0.0027 (8)	0.0008 (8)	−0.0003 (9)
C3	0.0268 (11)	0.0229 (10)	0.0267 (14)	0.0028 (9)	−0.0039 (9)	−0.0055 (9)
C4	0.0319 (11)	0.0379 (11)	0.0259 (13)	0.0058 (9)	−0.0053 (12)	−0.0081 (12)
C5	0.0409 (14)	0.0453 (14)	0.0221 (13)	0.0026 (11)	−0.0043 (11)	0.0007 (10)
C6	0.0411 (14)	0.0373 (13)	0.0262 (18)	−0.0032 (11)	−0.0027 (10)	0.0091 (9)
C7	0.0282 (11)	0.0284 (12)	0.0249 (13)	−0.0014 (9)	0.0009 (10)	0.0026 (9)
C8	0.0285 (11)	0.0174 (10)	0.0207 (13)	0.0014 (8)	−0.0044 (9)	−0.0037 (8)
C9	0.0239 (11)	0.0212 (10)	0.0211 (12)	0.0054 (8)	−0.0014 (8)	0.0010 (9)
C10	0.0261 (10)	0.0235 (10)	0.0263 (12)	0.0004 (9)	−0.0027 (9)	−0.0033 (9)
C11	0.0247 (11)	0.0337 (12)	0.0285 (13)	0.0018 (9)	−0.0011 (10)	−0.0039 (11)
C12	0.0258 (11)	0.0400 (14)	0.0281 (14)	0.0100 (10)	0.0008 (10)	−0.0024 (11)
C13	0.0330 (13)	0.0280 (11)	0.0247 (13)	0.0125 (9)	−0.0018 (10)	−0.0035 (9)
C14	0.0297 (11)	0.0215 (10)	0.0183 (12)	0.0042 (8)	−0.0036 (9)	−0.0017 (9)
C15	0.0250 (10)	0.0166 (9)	0.0184 (12)	0.0042 (8)	−0.0027 (9)	0.0015 (8)
C16	0.0207 (10)	0.0287 (12)	0.0363 (15)	0.0009 (9)	0.0041 (10)	0.0014 (10)
C17	0.0224 (10)	0.0171 (9)	0.0255 (13)	0.0051 (8)	0.0027 (9)	0.0012 (8)
C18	0.0356 (13)	0.0395 (13)	0.0261 (14)	0.0100 (10)	−0.0026 (10)	0.0058 (11)

Geometric parameters (Å, º)

Co1—O3	1.9953 (16)	C3—H3	0.9300
Co1—O1	2.0025 (14)	C4—C5	1.398 (4)
Co1—N1	2.0524 (18)	C4—H4	0.9300
Co1—N3	2.0568 (18)	C5—C6	1.380 (4)
S1—C7	1.737 (3)	C5—H5	0.9300
S1—C1	1.750 (2)	C6—C7	1.387 (4)
S2—C14	1.742 (2)	C6—H6	0.9300
S2—C8	1.748 (2)	C9—C10	1.392 (3)
O1—C15	1.280 (3)	C9—C14	1.396 (3)
O2—C15	1.250 (3)	C10—C11	1.385 (3)
O3—C17	1.283 (3)	C10—H10	0.9300
O4—C17	1.244 (3)	C11—C12	1.391 (4)
N1—C1	1.320 (3)	C11—H11	0.9300
N1—C2	1.391 (3)	C12—C13	1.383 (4)
N2—C1	1.324 (3)	C12—H12	0.9300
N2—H2A	0.8600	C13—C14	1.393 (3)
N2—H2B	0.8600	C13—H13	0.9300
N3—C8	1.325 (3)	C15—C16	1.498 (3)
N3—C9	1.408 (3)	C16—H16A	0.9600
N4—C8	1.325 (3)	C16—H16B	0.9600
N4—H4A	0.8600	C16—H16C	0.9600
N4—H4B	0.8600	C17—C18	1.489 (3)
C2—C3	1.390 (3)	C18—H18A	0.9600
C2—C7	1.404 (3)	C18—H18B	0.9600
C3—C4	1.383 (4)	C18—H18C	0.9600
O3—Co1—O1	128.90 (7)	C6—C7—S1	128.7 (2)
O3—Co1—N1	100.22 (7)	C2—C7—S1	109.80 (18)
O1—Co1—N1	112.35 (7)	N4—C8—N3	125.1 (2)
O3—Co1—N3	106.97 (7)	N4—C8—S2	119.52 (16)
O1—Co1—N3	101.51 (7)	N3—C8—S2	115.34 (16)
N1—Co1—N3	104.86 (8)	C10—C9—C14	119.6 (2)
C7—S1—C1	89.59 (11)	C10—C9—N3	125.9 (2)
C14—S2—C8	89.35 (10)	C14—C9—N3	114.6 (2)
C15—O1—Co1	101.42 (13)	C11—C10—C9	118.7 (2)
C17—O3—Co1	106.45 (13)	C11—C10—H10	120.6
C1—N1—C2	111.53 (19)	C9—C10—H10	120.6
C1—N1—Co1	123.21 (16)	C10—C11—C12	121.2 (2)
C2—N1—Co1	124.76 (14)	C10—C11—H11	119.4
C1—N2—H2A	120.0	C12—C11—H11	119.4
C1—N2—H2B	120.0	C13—C12—C11	120.8 (2)
H2A—N2—H2B	120.0	C13—C12—H12	119.6
C8—N3—C9	110.55 (19)	C11—C12—H12	119.6
C8—N3—Co1	124.70 (15)	C12—C13—C14	117.8 (2)
C9—N3—Co1	124.72 (14)	C12—C13—H13	121.1
C8—N4—H4A	120.0	C14—C13—H13	121.1
C8—N4—H4B	120.0	C13—C14—C9	121.8 (2)
H4A—N4—H4B	120.0	C13—C14—S2	127.97 (18)
N1—C1—N2	125.6 (2)	C9—C14—S2	110.19 (17)
N1—C1—S1	114.64 (18)	O2—C15—O1	120.54 (19)
N2—C1—S1	119.77 (16)	O2—C15—C16	120.4 (2)
C3—C2—N1	126.2 (2)	O1—C15—C16	119.05 (19)
C3—C2—C7	119.3 (2)	C15—C16—H16A	109.5
N1—C2—C7	114.4 (2)	C15—C16—H16B	109.5
C4—C3—C2	119.1 (2)	H16A—C16—H16B	109.5
C4—C3—H3	120.5	C15—C16—H16C	109.5
C2—C3—H3	120.5	H16A—C16—H16C	109.5
C3—C4—C5	121.1 (2)	H16B—C16—H16C	109.5
C3—C4—H4	119.4	O4—C17—O3	120.5 (2)
C5—C4—H4	119.4	O4—C17—C18	122.4 (2)
C6—C5—C4	120.3 (3)	O3—C17—C18	117.1 (2)
C6—C5—H5	119.8	C17—C18—H18A	109.5
C4—C5—H5	119.8	C17—C18—H18B	109.5
C5—C6—C7	118.6 (2)	H18A—C18—H18B	109.5
C5—C6—H6	120.7	C17—C18—H18C	109.5
C7—C6—H6	120.7	H18A—C18—H18C	109.5
C6—C7—C2	121.5 (2)	H18B—C18—H18C	109.5
O3—Co1—O1—C15	54.22 (16)	C5—C6—C7—S1	−177.9 (2)
N1—Co1—O1—C15	−71.10 (16)	C3—C2—C7—C6	−0.6 (4)
N3—Co1—O1—C15	177.39 (14)	N1—C2—C7—C6	−178.6 (2)
O1—Co1—O3—C17	41.08 (15)	C3—C2—C7—S1	177.85 (17)
N1—Co1—O3—C17	171.01 (13)	N1—C2—C7—S1	−0.1 (3)
N3—Co1—O3—C17	−79.88 (14)	C1—S1—C7—C6	178.3 (2)
O3—Co1—N1—C1	−25.49 (18)	C1—S1—C7—C2	−0.10 (18)
O1—Co1—N1—C1	114.33 (17)	C9—N3—C8—N4	−179.9 (2)
N3—Co1—N1—C1	−136.26 (17)	Co1—N3—C8—N4	1.9 (3)
O3—Co1—N1—C2	163.28 (16)	C9—N3—C8—S2	1.3 (3)
O1—Co1—N1—C2	−56.90 (18)	Co1—N3—C8—S2	−176.97 (11)
N3—Co1—N1—C2	52.51 (18)	C14—S2—C8—N4	−179.3 (2)
O3—Co1—N3—C8	119.32 (18)	C14—S2—C8—N3	−0.40 (18)
O1—Co1—N3—C8	−17.8 (2)	C8—N3—C9—C10	177.8 (2)
N1—Co1—N3—C8	−134.85 (18)	Co1—N3—C9—C10	−4.0 (3)
O3—Co1—N3—C9	−58.67 (19)	C8—N3—C9—C14	−1.7 (3)
O1—Co1—N3—C9	164.26 (18)	Co1—N3—C9—C14	176.49 (16)
N1—Co1—N3—C9	47.16 (19)	C14—C9—C10—C11	−1.0 (4)
C2—N1—C1—N2	−180.0 (2)	N3—C9—C10—C11	179.5 (2)
Co1—N1—C1—N2	7.8 (3)	C9—C10—C11—C12	0.5 (4)
C2—N1—C1—S1	−0.4 (2)	C10—C11—C12—C13	0.4 (4)
Co1—N1—C1—S1	−172.64 (10)	C11—C12—C13—C14	−0.9 (4)
C7—S1—C1—N1	0.28 (18)	C12—C13—C14—C9	0.5 (4)
C7—S1—C1—N2	179.89 (19)	C12—C13—C14—S2	178.78 (19)
C1—N1—C2—C3	−177.5 (2)	C10—C9—C14—C13	0.4 (4)
Co1—N1—C2—C3	−5.4 (3)	N3—C9—C14—C13	−180.0 (2)
C1—N1—C2—C7	0.3 (3)	C10—C9—C14—S2	−178.12 (18)
Co1—N1—C2—C7	172.42 (15)	N3—C9—C14—S2	1.4 (3)
N1—C2—C3—C4	178.3 (2)	C8—S2—C14—C13	−179.0 (2)
C7—C2—C3—C4	0.6 (3)	C8—S2—C14—C9	−0.59 (18)
C2—C3—C4—C5	−0.2 (3)	Co1—O1—C15—O2	7.5 (2)
C3—C4—C5—C6	−0.2 (4)	Co1—O1—C15—C16	−171.31 (17)
C4—C5—C6—C7	0.1 (4)	Co1—O3—C17—O4	0.5 (2)
C5—C6—C7—C2	0.3 (4)	Co1—O3—C17—C18	179.22 (16)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···O3	0.86	2.03	2.806 (2)	150
N2—H2B···O2^i	0.86	2.01	2.857 (2)	167
N4—H4A···O1	0.86	2.07	2.850 (2)	150
N4—H4B···O4^ii	0.86	2.00	2.811 (3)	156

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