trans-Di­chlorido­bis­(secnidazole-κN³)copper(II)

The use of acetic acid (HOAc) in a reaction between CuCl₂·2H₂O and secnid­azole, an active pharmaceutical ingredient useful in the treatment against a variety of anaerobic Gram-positive and Gram-negative bacteria, affords the title complex, [CuCl₂(C₇H₁₁N₃O₃)₂]. This compound was previously synthesized using ethanol as solvent, although its crystal structure was not reported [Betanzos-Lara et al. (2013). Inorg. Chim. Acta, 397, 94–100]. In the mol­ecular complex, the Cu²⁺ cation is situated at an inversion centre and displays a square-planar coordination environment. There is a hydrogen-bonded framework based on inter­molecular O—H...Cl inter­actions, characterized by H...Cl separations of 2.28 (4) Å and O—H...Cl angles of 175 (3)°. The resulting supra­molecular network is based on R₂²(18) ring motifs, forming chains in the [010] direction.

Key indicators

Structure: I

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.041
• wR factor = 0.108
• Data-to-parameter ratio = 18.6

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT094_ALERT_2_C Ratio of Maximum / Minimum Residual Density ....       2.08 Report
PLAT242_ALERT_2_C Low    'MainMol' Ueq as Compared to Neighbors of         N2 Check
PLAT250_ALERT_2_C Large U3/U1 Ratio for <U(i,j)> Tensor(Resd    1)        2.5 Note
PLAT906_ALERT_3_C Large K Value in the Analysis of Variance ......      2.421 Check

Alert level G
PLAT154_ALERT_1_G The s.u.'s on the Cell Angles are Equal ..(Note)      0.004 Degree
PLAT480_ALERT_4_G Long H...A H-Bond Reported H6A      ..CL1      .       2.92 Ang.
PLAT484_ALERT_4_G Round D-H..A Angle Rep for C4       ..CL1      .        136 Degree
PLAT484_ALERT_4_G Round D-H..A Angle Rep for C6       ..CL1      .        152 Degree
PLAT484_ALERT_4_G Round D-H..A Angle Rep for C6       ..CL1      .        136 Degree
PLAT484_ALERT_4_G Round D-H..A Angle Rep for C7       ..O3       .        160 Degree
PLAT802_ALERT_4_G CIF Input Record(s) with more than 80 Characters          3 Info
PLAT910_ALERT_3_G Missing # of FCF Reflection(s) Below Theta(Min).          4 Note
                0  1  0,   0  0  1,   0  1  1,   0  0  2,
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600        255 Note
PLAT941_ALERT_3_G Average HKL Measurement Multiplicity ...........        4.3 Low
PLAT969_ALERT_5_G The 'Henn et al.' R-Factor-gap value ...........       1.91 Note
              Predicted wR2: Based on SigI   2  5.62 or SHELX Weight 10.55       
PLAT978_ALERT_2_G Number C-C Bonds with Positive Residual Density.          3 Info

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   4 ALERT level C = Check. Ensure it is not caused by an omission or oversight
  12 ALERT level G = General information/check it is not something unexpected

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

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Computing details

trans-Dichloridobis(secnidazole-κN³)copper(II)

Crystal data

[CuCl2(C7H11N3O3)2]	Z = 1
Mr = 504.81	F(000) = 259
Triclinic, P1	Dx = 1.646 Mg m^−3
a = 4.6536 (3) Å	Mo Kα radiation, λ = 0.71073 Å
b = 8.2542 (3) Å	Cell parameters from 4331 reflections
c = 13.6820 (6) Å	θ = 4.3–28.4°
α = 78.092 (4)°	µ = 1.38 mm^−1
β = 82.801 (4)°	T = 298 K
γ = 85.469 (4)°	Plate, blue
V = 509.42 (4) Å^3	0.28 × 0.21 × 0.10 mm

Data collection

SuperNova, Dual, AtlasS2 diffractometer	2582 independent reflections
Radiation source: micro-focus sealed X-ray tube, SuperNova (Mo) X-ray Source	1956 reflections with I > 2σ(I)
Mirror monochromator	Rint = 0.066
Detector resolution: 5.1970 pixels mm^-1	θmax = 29.5°, θmin = 3.2°
ω scans	h = −6→5
Absorption correction: multi-scan (CrysAlisPro; Rigaku OD, 2022)	k = −11→11
Tmin = 0.879, Tmax = 1.000	l = −18→18
11147 measured reflections

Refinement

Refinement on F^2	Primary atom site location: dual
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.041	Hydrogen site location: mixed
wR(F^2) = 0.108	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	w = 1/[σ^2(Fo^2) + (0.0399P)^2 + 0.261P] where P = (Fo^2 + 2Fc^2)/3
2582 reflections	(Δ/σ)max < 0.001
139 parameters	Δρmax = 0.70 e Å^−3
0 restraints	Δρmin = −0.33 e Å^−3
0 constraints

Special details

Refinement. Methine, methylene and methyl H atoms were refined using a riding model and calculated displacement parameters, while hydroxy H atom (H3) was refined with free coordinates and isotropic displacement parameter.

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

	x	y	z	Uiso*/Ueq
Cu1	0.500000	0.000000	0.500000	0.04075 (17)
Cl1	0.26976 (17)	−0.14756 (8)	0.41467 (5)	0.0491 (2)
O1	0.7606 (6)	0.3821 (3)	0.04775 (15)	0.0687 (7)
O2	1.0650 (7)	0.1867 (4)	0.0998 (2)	0.1057 (12)
O3	0.7513 (5)	0.6770 (3)	0.27030 (16)	0.0542 (5)
N1	0.5217 (4)	0.3783 (2)	0.24801 (14)	0.0310 (4)
N2	0.8580 (6)	0.2806 (3)	0.11389 (17)	0.0495 (6)
N3	0.5786 (5)	0.1665 (2)	0.37287 (15)	0.0381 (5)
C2	0.4408 (5)	0.3135 (3)	0.34601 (17)	0.0324 (5)
C4	0.7580 (7)	0.1368 (3)	0.29152 (19)	0.0446 (7)
H4	0.882134	0.043325	0.289156	0.054*
C5	0.7251 (6)	0.2663 (3)	0.21463 (18)	0.0371 (6)
C6	0.2311 (6)	0.3957 (4)	0.4130 (2)	0.0488 (7)
H6A	0.308953	0.495324	0.422023	0.073*
H6B	0.195815	0.322391	0.477062	0.073*
H6C	0.052384	0.422977	0.383621	0.073*
C7	0.4181 (5)	0.5424 (3)	0.19434 (19)	0.0367 (6)
H7A	0.243775	0.579365	0.232279	0.044*
H7B	0.367519	0.531933	0.129350	0.044*
C8	0.6415 (6)	0.6722 (3)	0.17891 (19)	0.0408 (6)
H8	0.804035	0.640327	0.132601	0.049*
C9	0.5105 (8)	0.8384 (4)	0.1286 (2)	0.0617 (9)
H9A	0.350851	0.873264	0.172485	0.093*
H9B	0.442936	0.827624	0.066869	0.093*
H9C	0.655143	0.919358	0.114551	0.093*
H3	0.598 (9)	0.730 (5)	0.310 (3)	0.084 (12)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.0753 (4)	0.0250 (2)	0.0210 (2)	−0.0102 (2)	−0.0118 (2)	0.00433 (16)
Cl1	0.0764 (5)	0.0412 (4)	0.0320 (3)	−0.0149 (3)	−0.0117 (3)	−0.0050 (3)
O1	0.1028 (18)	0.0693 (15)	0.0242 (10)	0.0088 (13)	0.0001 (11)	0.0037 (10)
O2	0.133 (3)	0.096 (2)	0.0610 (17)	0.056 (2)	0.0316 (16)	−0.0013 (15)
O3	0.0585 (13)	0.0574 (13)	0.0476 (12)	0.0023 (10)	−0.0117 (10)	−0.0113 (10)
N1	0.0391 (11)	0.0283 (10)	0.0222 (10)	−0.0017 (8)	−0.0046 (8)	0.0037 (8)
N2	0.0718 (17)	0.0423 (13)	0.0300 (12)	0.0029 (12)	0.0036 (11)	−0.0051 (10)
N3	0.0633 (14)	0.0253 (10)	0.0229 (10)	−0.0046 (9)	−0.0065 (9)	0.0030 (8)
C2	0.0423 (13)	0.0289 (12)	0.0237 (11)	−0.0070 (10)	−0.0049 (9)	0.0024 (9)
C4	0.0704 (19)	0.0309 (13)	0.0300 (14)	0.0092 (12)	−0.0083 (12)	−0.0032 (11)
C5	0.0540 (15)	0.0312 (12)	0.0230 (12)	0.0018 (11)	−0.0028 (10)	−0.0006 (10)
C6	0.0539 (17)	0.0496 (16)	0.0347 (15)	−0.0017 (13)	0.0105 (12)	0.0007 (12)
C7	0.0405 (13)	0.0358 (13)	0.0273 (12)	0.0044 (10)	−0.0069 (10)	0.0082 (10)
C8	0.0559 (16)	0.0334 (13)	0.0297 (13)	0.0002 (12)	−0.0048 (11)	0.0006 (10)
C9	0.097 (3)	0.0335 (15)	0.0472 (18)	0.0074 (15)	−0.0099 (17)	0.0058 (13)

Geometric parameters (Å, º)

Cu1—N3	1.9953 (19)	C2—C6	1.477 (4)
Cu1—N3^i	1.9953 (19)	C4—C5	1.350 (3)
Cu1—Cl1	2.2586 (6)	C4—H4	0.9300
Cu1—Cl1^i	2.2586 (6)	C6—H6A	0.9600
O1—N2	1.207 (3)	C6—H6B	0.9600
O2—N2	1.210 (3)	C6—H6C	0.9600
O3—C8	1.417 (3)	C7—C8	1.517 (4)
O3—H3	0.97 (4)	C7—H7A	0.9700
N1—C2	1.355 (3)	C7—H7B	0.9700
N1—C5	1.373 (3)	C8—C9	1.520 (4)
N1—C7	1.478 (3)	C8—H8	0.9800
N2—C5	1.424 (3)	C9—H9A	0.9600
N3—C2	1.331 (3)	C9—H9B	0.9600
N3—C4	1.358 (3)	C9—H9C	0.9600
N3—Cu1—N3^i	180.0	C2—C6—H6A	109.5
N3—Cu1—Cl1	88.73 (6)	C2—C6—H6B	109.5
N3^i—Cu1—Cl1	91.27 (6)	H6A—C6—H6B	109.5
N3—Cu1—Cl1^i	91.27 (6)	C2—C6—H6C	109.5
N3^i—Cu1—Cl1^i	88.73 (6)	H6A—C6—H6C	109.5
Cl1—Cu1—Cl1^i	180.00 (4)	H6B—C6—H6C	109.5
C8—O3—H3	106 (2)	N1—C7—C8	112.9 (2)
C2—N1—C5	105.98 (19)	N1—C7—H7A	109.0
C2—N1—C7	124.6 (2)	C8—C7—H7A	109.0
C5—N1—C7	129.3 (2)	N1—C7—H7B	109.0
O1—N2—O2	123.5 (3)	C8—C7—H7B	109.0
O1—N2—C5	119.7 (2)	H7A—C7—H7B	107.8
O2—N2—C5	116.8 (2)	O3—C8—C7	111.3 (2)
C2—N3—C4	107.4 (2)	O3—C8—C9	113.4 (2)
C2—N3—Cu1	127.62 (18)	C7—C8—C9	109.2 (2)
C4—N3—Cu1	124.32 (17)	O3—C8—H8	107.6
N3—C2—N1	110.2 (2)	C7—C8—H8	107.6
N3—C2—C6	125.2 (2)	C9—C8—H8	107.6
N1—C2—C6	124.6 (2)	C8—C9—H9A	109.5
C5—C4—N3	108.2 (2)	C8—C9—H9B	109.5
C5—C4—H4	125.9	H9A—C9—H9B	109.5
N3—C4—H4	125.9	C8—C9—H9C	109.5
C4—C5—N1	108.2 (2)	H9A—C9—H9C	109.5
C4—C5—N2	126.7 (2)	H9B—C9—H9C	109.5
N1—C5—N2	125.0 (2)
C4—N3—C2—N1	1.5 (3)	C2—N1—C5—C4	1.2 (3)
Cu1—N3—C2—N1	−169.46 (16)	C7—N1—C5—C4	177.2 (2)
C4—N3—C2—C6	−178.1 (3)	C2—N1—C5—N2	176.6 (3)
Cu1—N3—C2—C6	10.9 (4)	C7—N1—C5—N2	−7.4 (4)
C5—N1—C2—N3	−1.7 (3)	O1—N2—C5—C4	162.4 (3)
C7—N1—C2—N3	−178.0 (2)	O2—N2—C5—C4	−16.9 (5)
C5—N1—C2—C6	177.9 (2)	O1—N2—C5—N1	−12.1 (4)
C7—N1—C2—C6	1.6 (4)	O2—N2—C5—N1	168.5 (3)
C2—N3—C4—C5	−0.8 (3)	C2—N1—C7—C8	103.5 (3)
Cu1—N3—C4—C5	170.60 (19)	C5—N1—C7—C8	−71.9 (3)
N3—C4—C5—N1	−0.3 (3)	N1—C7—C8—O3	−51.0 (3)
N3—C4—C5—N2	−175.6 (3)	N1—C7—C8—C9	−176.9 (2)

Symmetry code: (i) −x+1, −y, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···Cl1^ii	0.97 (4)	2.28 (4)	3.252 (2)	175 (3)
C4—H4···Cl1^iii	0.93	2.81	3.537 (3)	136
C6—H6A···Cl1^ii	0.96	2.92	3.793 (3)	152
C6—H6B···Cl1^iv	0.96	2.79	3.546 (3)	136
C7—H7A···O3^v	0.97	2.40	3.327 (3)	160
C7—H7B···O1^vi	0.97	2.51	3.436 (3)	159

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