trans-Bis(1,1,1,5,5,5-hexa­fluoro­pentane-2,4-dionato-κ2O,O′)bis­(4-methyl-1,2,3-selenadiazole-κN3)copper(II)

Boag, N.M.; Jackson, A.D.; Lickiss, P.D.; Pilkington, R.D.; Redhouse, A.D.

doi:10.1107/S1600536810001297

metal-organic compounds

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ISSN: 2056-9890

Volume 66| Part 2| February 2010| Page m241

https://doi.org/10.1107/S1600536810001297

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trans-Bis(1,1,1,5,5,5-hexafluoropentane-2,4-dionato-κ²O,O′)bis(4-methyl-1,2,3-selenadiazole-κN³)copper(II)

Neil M. Boag,^a Andrew D. Jackson,^a Paul D. Lickiss,^b ^* Richard D. Pilkington ^a and Alan D. Redhouse ^a

^aSchool of Computing, Science and Engineering, University of Salford, Salford M5 4WT, England, and ^bDepartment of Chemistry, Imperial College London, South Kensington, London SW7 2AZ, England
^*Correspondence e-mail: p.lickiss@imperial.co.uk

(Received 18 November 2009; accepted 11 January 2010; online 30 January 2010)

In the title compound, [Cu(C₅HF₆O₂)₂(C₃H₄N₂Se)₂], the Cu^II atom (site symmetry $[\overline{1}]$ ) is coordinated by two O,O′-bidentate 1,1,1,5,5,5-hexafluoro-2,4-pentanedione (hp) ligands and two 4-methyl-1,2,3-selenadiazole molecules, resulting in a slightly distorted trans-CuN₂O₄ octahedral geometry in which the cis angles deviate by less than 3° from 90°. The selenadiazole plane is canted at 73.13 (17)° to the square plane defined by the pentanedionate O atoms. The F atoms of one of the hp ligands are disordered over two sets of sites in a 0.66 (3):0.34 (3) ratio. There are no significant intermolecular interactions in the crystal.

Related literature

Similar stuctures are exhibited by bis(hexafluoropentadionato) copper complexes of imidazole (Colacio et al., 2000 ), pyrazole (Kogane et al., 1990 ; Fokin et al., 2002 ) and substituted pyridines (De Panthou et al., 1996 ; Iwahori et al., 2001 ; Sano et al., 1997 ).

Experimental

Crystal data

[Cu(C₅HF₆O₂)₂(C₃H₄N₂Se)₂]
M_r = 771.74
Monoclinic, P 2₁ /c
a = 8.191 (2) Å
b = 14.390 (4) Å
c = 11.429 (4) Å
β = 104.86 (3)°
V = 1302.1 (7) Å³
Z = 2
Mo Kα radiation
μ = 3.75 mm⁻¹
T = 293 K
0.25 × 0.25 × 0.25 mm

Data collection

Nicolet R3m/V diffractometer
Absorption correction: ψ scan (SHELXTL; Sheldrick, 2008 ) T_min = 0.755, T_max = 0.793
3218 measured reflections
3014 independent reflections
1894 reflections with I > 2σ(I)
R_int = 0.048
3 standard reflections every 97 reflections intensity decay: none

Refinement

R[F² > 2σ(F²)] = 0.055
wR(F²) = 0.126
S = 1.03
3014 reflections
215 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.44 e Å⁻³
Δρ_min = −0.42 e Å⁻³

Table 1
Selected bond lengths (Å)

Cu—O1	1.967 (3)
Cu—O2	1.981 (3)
Cu—N1	2.391 (4)

Data collection: XSCANS (Siemens, 1996 ); cell refinement: XSCANS; data reduction: XSCANS; program(s) used to solve structure: SHELXL97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536810001297/hb5239sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810001297/hb5239Isup2.hkl

checkCIF report

Comment top

The title molecule, [Cu(C₃HF₆O₂)₂(C₃H₄N₂Se)₂], (I) was prepared as a potential precursor to CuInSe₂. The molecule (Fig. 1) is centrosymmetric resulting in pairs of equivalent ligands lying trans to each other in a slightly distorted octahedral coordination geometry in which the cis angles deviate less than 3° from right angles. The Cu is bound to N1 of the selenadiazole whose plane is canted at 73.13 (0.17) ° to the square plane defined by the pentanedionato oxygen atoms. The Cu—N bond is elongated. There are no intermolecular interactions.

Related literature top

Similar stuctures are exhibited by bis(hexafluoropentadionato) copper complexes of imidazole (Colacio et al. 2000), pyrazole (Kogane et al. 1990; Fokin et al. (2002) and substituted pyridines (De Panthou et al. 1996; Iwahori et al. 2001; Sano et al. (1997).

Experimental top

A solution of 4-methyl-1,2,3-selenadiazole (4.65 g, 0.032 mol) in dichloromethane was added dropwise to a solution of Cu(hfac)₂.xH₂O (7.84 g, 0.016 mol) in dichloromethane/toluene (50 ml) at 273 K in the absence of light. The mixture was stirred for 12 h, the solvent removed in vacuo and the residue dissolved in warm toluene. Slow cooling afforded olive-green parallelepipeds of (I). Yield 8.13 g (65%), mpt. 354–356 K. Found: C, 24.86; H, 1.24; N, 7.31%. Calc.for C₁₆H₁₂CuF₁₂N₄O₄Se₂: C, 24.90; H, 1.31; N, 7.26%. µ 2.15 BM.

Structure description top

Computing details top

Data collection: XSCANS (Siemens, 1996); cell refinement: XSCANS (Siemens, 1996); data reduction: XSCANS (Siemens, 1996); program(s) used to solve structure: SHELXL97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure of (I), with 50% probability displacement ellipsoids. Hydrogen atoms and the fluorine atoms have been excluded for clarity.

trans-Bis(1,1,1,5,5,5-hexafluoropentane-2,4-dionato- κ²O,O')bis(4-methyl-1,2,3-selenadiazole- κN³)copper(II) top

Crystal data top

[Cu(C₅HF₆O₂)₂(C₃H₄N₂Se)₂]	D_x = 1.968 Mg m⁻³
M_r = 771.74	Melting point: 355 K
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 8.191 (2) Å	Cell parameters from 20 reflections
b = 14.390 (4) Å	θ = 7.9–14.5°
c = 11.429 (4) Å	µ = 3.75 mm⁻¹
β = 104.86 (3)°	T = 293 K
V = 1302.1 (7) Å³	Parallelpiped, green
Z = 2	0.25 × 0.25 × 0.25 mm
F(000) = 742

Data collection top

Nicolet R3m/V diffractometer	R_int = 0.048
Graphite monochromator	θ_max = 27.6°, θ_min = 2.3°
profile data from θ/2θ scans	h = −2→10
Absorption correction: ψ scan (SHELXTL; Sheldrick, 2008)	k = −6→18
T_min = 0.755, T_max = 0.793	l = −14→14
3218 measured reflections	3 standard reflections every 97 reflections
3014 independent reflections	intensity decay: none
1894 reflections with I > 2σ(I)

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.055	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.126	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ²(F_o²) + (0.0459P)² + 1.964P] where P = (F_o² + 2F_c²)/3
3014 reflections	(Δ/σ)_max < 0.001
215 parameters	Δρ_max = 0.44 e Å⁻³
0 restraints	Δρ_min = −0.42 e Å⁻³

Crystal data top

[Cu(C₅HF₆O₂)₂(C₃H₄N₂Se)₂]	V = 1302.1 (7) Å³
M_r = 771.74	Z = 2
Monoclinic, P2₁/c	Mo Kα radiation
a = 8.191 (2) Å	µ = 3.75 mm⁻¹
b = 14.390 (4) Å	T = 293 K
c = 11.429 (4) Å	0.25 × 0.25 × 0.25 mm
β = 104.86 (3)°

Data collection top

Nicolet R3m/V diffractometer	1894 reflections with I > 2σ(I)
Absorption correction: ψ scan (SHELXTL; Sheldrick, 2008)	R_int = 0.048
T_min = 0.755, T_max = 0.793	3 standard reflections every 97 reflections
3218 measured reflections	intensity decay: none
3014 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.055	0 restraints
wR(F²) = 0.126	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	Δρ_max = 0.44 e Å⁻³
3014 reflections	Δρ_min = −0.42 e Å⁻³
215 parameters

Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
Cu	0.0000	0.0000	0.5000	0.0467 (2)
Se	0.11516 (8)	0.14840 (4)	0.26686 (5)	0.0667 (2)
N1	0.0700 (6)	0.1433 (3)	0.4188 (4)	0.0564 (11)
N2	0.0391 (6)	0.2234 (3)	0.4541 (4)	0.0572 (11)
C6	0.0853 (8)	0.2732 (4)	0.2739 (5)	0.0628 (15)
C7	0.0470 (7)	0.2966 (4)	0.3777 (5)	0.0577 (13)
C71	0.0087 (11)	0.3911 (4)	0.4164 (6)	0.093 (2)
H71A	−0.0143	0.4322	0.3479	0.140*
H71B	0.1040	0.4139	0.4772	0.140*
H71C	−0.0881	0.3882	0.4489	0.140*
O1	−0.1707 (5)	−0.0178 (2)	0.3457 (3)	0.0546 (9)
O2	−0.1614 (5)	0.0692 (2)	0.5702 (3)	0.0520 (8)
C1	−0.3071 (7)	0.0274 (4)	0.3148 (5)	0.0582 (14)
C11	−0.4037 (9)	0.0109 (5)	0.1836 (6)	0.0771 (19)
F11	−0.5552 (6)	0.0472 (5)	0.1545 (4)	0.157 (3)
F12	−0.3218 (6)	0.0490 (3)	0.1084 (3)	0.1142 (15)
F13	−0.4170 (6)	−0.0780 (3)	0.1545 (4)	0.1076 (14)
C2	−0.3728 (8)	0.0879 (4)	0.3859 (5)	0.0674 (16)
C3	−0.2960 (7)	0.1034 (4)	0.5075 (5)	0.0541 (13)
C31	−0.3885 (10)	0.1722 (5)	0.5750 (7)	0.0782 (19)
F311	−0.318 (2)	0.2515 (8)	0.581 (3)	0.145 (9)	0.66 (3)
F312	−0.5418 (12)	0.1700 (18)	0.5425 (19)	0.161 (10)	0.66 (3)
F313	−0.349 (2)	0.1452 (18)	0.6957 (10)	0.137 (6)	0.66 (3)
F321	−0.300 (2)	0.210 (2)	0.663 (3)	0.105 (10)	0.34 (3)
F322	−0.520 (6)	0.141 (2)	0.591 (5)	0.18 (2)	0.34 (3)
F323	−0.457 (6)	0.2452 (19)	0.4941 (19)	0.138 (14)	0.34 (3)
H2	−0.475 (7)	0.118 (4)	0.347 (5)	0.065 (17)*
H6	0.085 (9)	0.314 (5)	0.207 (7)	0.12 (3)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cu	0.0603 (5)	0.0401 (4)	0.0375 (4)	0.0048 (4)	0.0085 (4)	−0.0043 (4)
Se	0.0834 (5)	0.0652 (4)	0.0568 (4)	0.0044 (3)	0.0276 (3)	−0.0066 (3)
N1	0.072 (3)	0.051 (3)	0.051 (2)	0.001 (2)	0.023 (2)	0.004 (2)
N2	0.081 (3)	0.047 (3)	0.047 (2)	0.002 (2)	0.023 (2)	0.005 (2)
C6	0.080 (4)	0.063 (4)	0.049 (3)	−0.001 (3)	0.022 (3)	0.012 (3)
C7	0.080 (4)	0.047 (3)	0.046 (3)	0.002 (3)	0.014 (3)	0.009 (2)
C71	0.152 (7)	0.059 (4)	0.076 (4)	0.002 (4)	0.044 (5)	0.001 (3)
O1	0.065 (2)	0.051 (2)	0.0436 (18)	0.0042 (18)	0.0060 (17)	−0.0060 (16)
O2	0.064 (2)	0.047 (2)	0.0444 (18)	0.0014 (17)	0.0132 (17)	−0.0044 (15)
C1	0.067 (4)	0.058 (3)	0.045 (3)	0.003 (3)	0.007 (3)	−0.002 (2)
C11	0.077 (4)	0.092 (5)	0.052 (4)	0.012 (4)	−0.003 (3)	−0.016 (3)
F11	0.098 (3)	0.260 (7)	0.081 (3)	0.080 (4)	−0.033 (2)	−0.062 (4)
F12	0.149 (4)	0.133 (4)	0.052 (2)	−0.001 (3)	0.011 (2)	0.013 (2)
F13	0.130 (4)	0.102 (3)	0.072 (2)	−0.014 (3)	−0.008 (2)	−0.024 (2)
C2	0.061 (4)	0.074 (4)	0.060 (3)	0.013 (3)	0.003 (3)	−0.014 (3)
C3	0.056 (3)	0.048 (3)	0.061 (3)	−0.001 (3)	0.019 (3)	−0.010 (3)
C31	0.081 (5)	0.070 (5)	0.089 (5)	−0.002 (4)	0.032 (4)	−0.030 (4)
F311	0.164 (16)	0.064 (6)	0.23 (2)	0.004 (7)	0.095 (18)	−0.043 (9)
F312	0.045 (6)	0.27 (2)	0.158 (13)	0.041 (8)	−0.001 (6)	−0.123 (14)
F313	0.147 (12)	0.188 (15)	0.088 (6)	0.053 (10)	0.052 (7)	−0.030 (8)
F321	0.067 (11)	0.12 (2)	0.104 (17)	0.027 (14)	−0.015 (11)	−0.071 (14)
F322	0.23 (4)	0.132 (17)	0.27 (5)	−0.10 (2)	0.22 (4)	−0.10 (2)
F323	0.21 (3)	0.101 (14)	0.094 (12)	0.105 (18)	0.034 (16)	0.019 (10)

Geometric parameters (Å, º) top

Cu—O1	1.967 (3)	C1—C2	1.390 (8)
Cu—O2	1.981 (3)	C1—C11	1.524 (8)
Cu—N1	2.391 (4)	C11—F11	1.308 (7)
Se—C6	1.817 (6)	C11—F13	1.318 (8)
Se—N1	1.867 (4)	C11—F12	1.336 (8)
N1—N2	1.268 (6)	C2—C3	1.389 (8)
N2—C7	1.380 (6)	C2—H2	0.95 (6)
C6—C7	1.345 (7)	C3—C31	1.565 (8)
C6—H6	0.97 (8)	C31—F312	1.214 (12)
C7—C71	1.488 (8)	C31—F311	1.273 (12)
C71—H71A	0.96	C31—F313	1.389 (15)
C71—H71B	0.96	C31—F321	1.204 (17)
C71—H71C	0.96	C31—F322	1.23 (2)
O1—C1	1.262 (6)	C31—F323	1.418 (17)
O2—C3	1.252 (6)

O1—Cu—O2ⁱ	88.06 (14)	O1—C1—C11	113.2 (5)
O1—Cu—O2	91.94 (14)	C2—C1—C11	119.5 (5)
O1—Cu—N1	87.15 (15)	F11—C11—F13	108.2 (6)
O1ⁱ—Cu—N1	92.85 (15)	F11—C11—F12	105.9 (6)
O2ⁱ—Cu—N1	91.44 (15)	F13—C11—F12	105.0 (6)
O2—Cu—N1	88.57 (15)	F11—C11—C1	114.0 (5)
C6—Se—N1	86.4 (2)	F13—C11—C1	112.8 (6)
N2—N1—Se	111.3 (3)	F12—C11—C1	110.4 (6)
N2—N1—Cu	125.0 (3)	C3—C2—C1	122.8 (6)
Se—N1—Cu	121.3 (2)	C3—C2—H2	121 (3)
N1—N2—C7	116.6 (4)	C1—C2—H2	116 (3)
C7—C6—Se	110.6 (4)	O2—C3—C2	128.1 (5)
C7—C6—H6	126 (4)	O2—C3—C31	115.7 (5)
Se—C6—H6	123 (4)	C2—C3—C31	116.3 (6)
C6—C7—N2	115.2 (5)	F312—C31—F311	117.2 (13)
C6—C7—C71	127.2 (5)	F312—C31—F313	104.9 (12)
N2—C7—C71	117.5 (5)	F311—C31—F313	102.0 (11)
C7—C71—H71A	109.5	F312—C31—C3	115.2 (8)
C7—C71—H71B	109.5	F311—C31—C3	109.0 (8)
H71A—C71—H71B	109.5	F313—C31—C3	107.1 (8)
C7—C71—H71C	109.5	F321—C31—F322	114 (2)
H71A—C71—H71C	109.5	F321—C31—F323	105.4 (16)
H71B—C71—H71C	109.5	F322—C31—F323	99 (2)
C1—O1—Cu	123.9 (3)	F321—C31—C3	115.3 (10)
C3—O2—Cu	123.2 (3)	F322—C31—C3	113.4 (14)
O1—C1—C2	127.4 (5)	F323—C31—C3	107.9 (9)

C6—Se—N1—N2	0.8 (4)	Cu—O1—C1—C11	171.1 (4)
C6—Se—N1—Cu	164.0 (3)	O1—C1—C11—F11	171.4 (6)
O1—Cu—N1—N2	109.9 (4)	C2—C1—C11—F11	−8.8 (10)
O1ⁱ—Cu—N1—N2	−70.1 (4)	O1—C1—C11—F13	47.5 (8)
O2ⁱ—Cu—N1—N2	−162.1 (4)	C2—C1—C11—F13	−132.7 (6)
O2—Cu—N1—N2	17.9 (4)	O1—C1—C11—F12	−69.6 (7)
O1—Cu—N1—Se	−50.9 (3)	C2—C1—C11—F12	110.2 (7)
O1ⁱ—Cu—N1—Se	129.1 (3)	O1—C1—C2—C3	−3.2 (11)
O2ⁱ—Cu—N1—Se	37.1 (3)	C11—C1—C2—C3	177.1 (6)
O2—Cu—N1—Se	−142.9 (3)	Cu—O2—C3—C2	11.9 (8)
Se—N1—N2—C7	−1.0 (6)	Cu—O2—C3—C31	−168.1 (4)
Cu—N1—N2—C7	−163.4 (4)	C1—C2—C3—O2	1.3 (10)
N1—Se—C6—C7	−0.5 (5)	C1—C2—C3—C31	−178.8 (6)
Se—C6—C7—N2	0.1 (7)	O2—C3—C31—F312	−145.3 (18)
Se—C6—C7—C71	−178.2 (6)	C2—C3—C31—F312	34.8 (19)
N1—N2—C7—C6	0.6 (8)	O2—C3—C31—F311	80.6 (17)
N1—N2—C7—C71	179.1 (6)	C2—C3—C31—F311	−99.4 (16)
O2ⁱ—Cu—O1—C1	−164.5 (4)	O2—C3—C31—F313	−29.0 (14)
O2—Cu—O1—C1	15.5 (4)	C2—C3—C31—F313	151.0 (13)
N1ⁱ—Cu—O1—C1	107.0 (4)	O2—C3—C31—F321	24 (3)
N1—Cu—O1—C1	−73.0 (4)	C2—C3—C31—F321	−156 (3)
O1—Cu—O2—C3	−16.9 (4)	O2—C3—C31—F322	−110 (3)
O1ⁱ—Cu—O2—C3	163.1 (4)	C2—C3—C31—F322	71 (3)
N1ⁱ—Cu—O2—C3	−109.8 (4)	O2—C3—C31—F323	142 (2)
N1—Cu—O2—C3	70.2 (4)	C2—C3—C31—F323	−38 (3)
Cu—O1—C1—C2	−8.6 (8)

Symmetry code: (i) −x, −y, −z+1.

Experimental details

Crystal data
Chemical formula	[Cu(C₅HF₆O₂)₂(C₃H₄N₂Se)₂]
M_r	771.74
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	8.191 (2), 14.390 (4), 11.429 (4)
β (°)	104.86 (3)
V (Å³)	1302.1 (7)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	3.75
Crystal size (mm)	0.25 × 0.25 × 0.25

Data collection
Diffractometer	Nicolet R3m/V
Absorption correction	ψ scan (SHELXTL; Sheldrick, 2008)
T_min, T_max	0.755, 0.793
No. of measured, independent and observed [I > 2σ(I)] reflections	3218, 3014, 1894
R_int	0.048
(sin θ/λ)_max (Å⁻¹)	0.651

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.055, 0.126, 1.03
No. of reflections	3014
No. of parameters	215
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.44, −0.42

Computer programs: XSCANS (Siemens, 1996), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Selected geometric parameters (Å, º) top

Cu—O1	1.967 (3)	Cu—N1	2.391 (4)
Cu—O2	1.981 (3)

C6—C7—N2	115.2 (5)

Acknowledgements

We wish to thank Dr D. Shah, Imperial College, for experimental assistance.

References

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