1,1′-(Ethane-1,2-di­yl)dipyridinium dichromate(VI)

Gholizadeh, M.; Pourayoubi, M.; Kia, M.; Rheingold, A.L.; Golen, J.A.

doi:10.1107/S1600536812005430

metal-organic compounds

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ISSN: 2056-9890

Volume 68| Part 3| March 2012| Page m305

doi:10.1107/S1600536812005430

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1,1′-(Ethane-1,2-diyl)dipyridinium dichromate(VI)

Mostafa Gholizadeh,^a ^* Mehrdad Pourayoubi,^a Mehdi Kia,^b Arnold L. Rheingold ^c and James A. Golen ^c

^aDepartment of Chemistry, Ferdowsi University of Mashhad, Mashhad 91779, Iran, ^bDepartment of Chemistry, Sabzevar Tarbiat Moallem University, Sabzevar, Iran, and ^cDepartment of Chemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
^*Correspondence e-mail: gholizadeh_mostafa@yahoo.com

(Received 25 January 2012; accepted 7 February 2012; online 17 February 2012)

In the cation of the title salt, (C₁₂H₁₄N₂)[Cr₂O₇], the two pyridinium moieties are in an anti orientation with respect to one another. The dihedral angle between the pyridine rings is 6.3 (2)°. The N—C—C—N torsion angle is 177.5 (2)°. In the dianion, the Cr^VI ions are in a slightly distorted tetrahedral coordination environment and the bond angles at the independent Cr^VI ions are in the ranges 105.93 (10)–110.60 (11) and 107.35 (11)–111.07 (12)°. The Cr—O—Cr angle is 127.96 (12)°. The crystal used was an inversion twin with refined components of 0.510 (19) and 0.490 (19).

Related literature

For the crystal structures of the salts with formula [C₅H₅NCH₂CH₂NC₅H₅]²⁺·2X⁻ [X⁻ = IO₃⁻, IO₄⁻], the preparation of 1,1′-(ethane-1,2-diyl)dipyridinium dibromide and the orientation of pyridine moieties, see: Gholizadeh, Maleki et al. (2011 ); Gholizadeh, Hojati et al. (2011 ). For dichromate salts, see: Lennartson & Håkansson (2009 ); Averbuch-Pouchot et al. (1984 ).

Experimental

Crystal data

(C₁₂H₁₄N₂)[Cr₂O₇]
M_r = 402.25
Monoclinic, P 2₁
a = 8.2882 (4) Å
b = 9.0722 (4) Å
c = 10.0179 (5) Å
β = 91.882 (1)°
V = 752.86 (6) Å³
Z = 2
Mo Kα radiation
μ = 1.48 mm⁻¹
T = 100 K
0.22 × 0.15 × 0.15 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ) T_min = 0.737, T_max = 0.808
5446 measured reflections
2628 independent reflections
2546 reflections with I > 2σ(I)
R_int = 0.025

Refinement

R[F² > 2σ(F²)] = 0.027
wR(F²) = 0.067
S = 1.04
2628 reflections
209 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.47 e Å⁻³
Δρ_min = −0.21 e Å⁻³
Absolute structure: Flack (1983 ), 1163 Friedel pairs
Flack parameter: 0.510 (19)

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL and enCIFer (Allen et al., 2004 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812005430/lh5410sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812005430/lh5410Isup2.hkl

checkCIF report

Comment top

In recently published papers, the structure determinations of [C₅H₅NCH₂CH₂NC₅H₅]²⁺.2X^- [X^- = IO₃^- (Gholizadeh, Maleki et al., 2011) and IO₄^- (Gholizadeh, Hojati et al., 2011)] have been investigated. Structure determination of the title salt, [C₅H₅NCH₂CH₂NC₅H₅]²⁺.Cr₂O₇^2- (Fig. 1), was performed as a part of a project on the synthesis of a new hybrid compound containing an organic cation and an inorganic oxidant anion.

In the dication, two pyridinium moieties are anti-oriented with respect to one another similar to those observed in the 1,1'-(ethane-1,2-diyl)dipyridinium salts with iodate and periodate counter ions (Gholizadeh, Maleki et al., 2011; Gholizadeh, Hojati et al., 2011). In the dianion, each Cr^VI ion is in a slightly distorted tetrahedral coordination environment. The two pyridinium fragments in the cation and the two CrO₃ units in the anion are not symmetrically equivalent.

The Cr—O bonds (with lengths of 1.777 (2) & 1.790 (2) Å) in the Cr—O—Cr fragment are longer than the other Cr—O bonds (in the range of 1.611 (2) to 1.624 (2) Å). The bond lengths and angles in the dichromate anion are within the expected values in the reported dichromate salts (Lennartson & Håkansson, 2009; Averbuch-Pouchot et al., 1984).

Related literature top

For the crystal structures of the salts with formula [C₅H₅NCH₂CH₂NC₅H₅]²⁺.2X^- [X^- = IO₃^-, IO₄^-], the preparation of 1,1'-(ethane-1,2-diyl)dipyridinium dibromide and the orientation of pyridine moieties, see: Gholizadeh, Maleki et al. (2011); Gholizadeh, Hojati et al. (2011). For dichromate salts, see: Lennartson & Håkansson (2009); Averbuch-Pouchot et al. (1984).

Experimental top

1,1'-(ethane-1,2-diyl)dipyridinium dibromide was prepared according to the procedure reported by Gholizadeh, Maleki et al., 2011 and Gholizadeh, Hojati et al., 2011.

Preparation of title salt: To a solution of 1,1'-(ethane-1,2-diyl)dipyridinium dibromide (10 mmol) in H₂O (25 ml), a solution of K₂Cr₂O₇ (10 mmol) in H₂O was added and stirred. After 1 h, the precipitate was filtered and washed with H₂O. Orange crystals, suitable for X-ray crystallography, were obtained from a solution of the title salt in H₂O at room temperature.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and enCIFer (Allen et al., 2004).

Figures top

Fig. 1. The molecular structure of the title compound. Ellipsoids are given at the 50% probability level.

1,1'-(Ethane-1,2-diyl)dipyridinium dichromate(VI) top

Crystal data top

(C₁₂H₁₄N₂)[Cr₂O₇]	F(000) = 408
M_r = 402.25	D_x = 1.774 Mg m⁻³
Monoclinic, P2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 3255 reflections
a = 8.2882 (4) Å	θ = 2.5–26.5°
b = 9.0722 (4) Å	µ = 1.48 mm⁻¹
c = 10.0179 (5) Å	T = 100 K
β = 91.882 (1)°	Block, orange
V = 752.86 (6) Å³	0.22 × 0.15 × 0.15 mm
Z = 2

Data collection top

Bruker APEXII CCD diffractometer	2628 independent reflections
Radiation source: fine-focus sealed tube	2546 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.025
ϕ and ω scans	θ_max = 25.3°, θ_min = 2.0°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −9→9
T_min = 0.737, T_max = 0.808	k = −10→10
5446 measured reflections	l = −12→12

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.027	H-atom parameters constrained
wR(F²) = 0.067	w = 1/[σ²(F_o²) + (0.0332P)² + 0.2849P] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max = 0.001
2628 reflections	Δρ_max = 0.47 e Å⁻³
209 parameters	Δρ_min = −0.21 e Å⁻³
1 restraint	Absolute structure: Flack (1983), 1163 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.510 (19)

Crystal data top

(C₁₂H₁₄N₂)[Cr₂O₇]	V = 752.86 (6) Å³
M_r = 402.25	Z = 2
Monoclinic, P2₁	Mo Kα radiation
a = 8.2882 (4) Å	µ = 1.48 mm⁻¹
b = 9.0722 (4) Å	T = 100 K
c = 10.0179 (5) Å	0.22 × 0.15 × 0.15 mm
β = 91.882 (1)°

Data collection top

Bruker APEXII CCD diffractometer	2628 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2005)	2546 reflections with I > 2σ(I)
T_min = 0.737, T_max = 0.808	R_int = 0.025
5446 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.027	H-atom parameters constrained
wR(F²) = 0.067	Δρ_max = 0.47 e Å⁻³
S = 1.04	Δρ_min = −0.21 e Å⁻³
2628 reflections	Absolute structure: Flack (1983), 1163 Friedel pairs
209 parameters	Absolute structure parameter: 0.510 (19)
1 restraint

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.

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 (Å²) top

	x	y	z	U_iso*/U_eq
Cr1	0.65538 (5)	0.04259 (4)	0.83530 (4)	0.01584 (13)
Cr2	0.35152 (5)	−0.03987 (5)	0.64354 (4)	0.01691 (13)
O1	0.7936 (2)	0.0097 (2)	0.7300 (2)	0.0250 (5)
O2	0.7001 (2)	0.1896 (2)	0.9204 (2)	0.0230 (5)
O3	0.6343 (3)	−0.0968 (2)	0.9351 (2)	0.0241 (5)
O4	0.4684 (3)	0.0804 (2)	0.7502 (2)	0.0255 (5)
O5	0.2177 (3)	−0.1216 (3)	0.7304 (2)	0.0312 (6)
O6	0.4687 (3)	−0.1613 (2)	0.5775 (2)	0.0251 (5)
O7	0.2677 (3)	0.0602 (3)	0.5277 (2)	0.0294 (5)
N1	0.2884 (3)	0.3914 (3)	0.6933 (2)	0.0177 (6)
N2	0.6566 (3)	0.5863 (3)	0.8330 (2)	0.0165 (6)
C1	0.1985 (4)	0.3157 (4)	0.7779 (3)	0.0207 (7)
H1	0.2448	0.2834	0.8608	0.025*
C2	0.0391 (4)	0.2840 (3)	0.7460 (3)	0.0213 (7)
H2	−0.0241	0.2291	0.8058	0.026*
C3	−0.0274 (4)	0.3334 (4)	0.6255 (3)	0.0218 (7)
H3	−0.1367	0.3118	0.6015	0.026*
C4	0.0658 (4)	0.4138 (4)	0.5407 (3)	0.0224 (7)
H4	0.0204	0.4503	0.4589	0.027*
C5	0.2256 (4)	0.4412 (4)	0.5753 (3)	0.0208 (7)
H5	0.2913	0.4949	0.5164	0.025*
C6	0.4621 (4)	0.4188 (3)	0.7282 (3)	0.0193 (7)
H6A	0.5255	0.4160	0.6461	0.023*
H6B	0.5033	0.3406	0.7891	0.023*
C7	0.4825 (3)	0.5674 (4)	0.7949 (3)	0.0192 (7)
H7A	0.4468	0.6467	0.7328	0.023*
H7B	0.4164	0.5724	0.8753	0.023*
C8	0.7158 (3)	0.5188 (3)	0.9456 (3)	0.0179 (6)
H8	0.6471	0.4605	0.9983	0.022*
C9	0.8761 (4)	0.5360 (4)	0.9823 (3)	0.0217 (6)
H9	0.9189	0.4901	1.0611	0.026*
C10	0.9750 (4)	0.6206 (4)	0.9038 (3)	0.0219 (7)
H10	1.0858	0.6328	0.9285	0.026*
C11	0.9116 (4)	0.6876 (4)	0.7886 (3)	0.0197 (7)
H11	0.9783	0.7456	0.7339	0.024*
C12	0.7493 (4)	0.6681 (4)	0.7551 (3)	0.0197 (7)
H12	0.7039	0.7129	0.6768	0.024*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cr1	0.0149 (2)	0.0163 (3)	0.0162 (2)	0.0001 (2)	−0.00137 (17)	−0.0007 (2)
Cr2	0.0149 (2)	0.0192 (3)	0.0165 (2)	−0.0025 (2)	−0.00182 (17)	0.0006 (2)
O1	0.0229 (11)	0.0267 (13)	0.0256 (11)	−0.0042 (9)	0.0042 (9)	−0.0029 (10)
O2	0.0232 (12)	0.0214 (12)	0.0239 (13)	0.0036 (9)	−0.0064 (9)	−0.0039 (10)
O3	0.0295 (12)	0.0219 (12)	0.0210 (11)	0.0040 (10)	0.0034 (9)	0.0030 (10)
O4	0.0215 (11)	0.0208 (12)	0.0333 (13)	−0.0003 (9)	−0.0105 (9)	−0.0024 (10)
O5	0.0265 (13)	0.0378 (15)	0.0296 (13)	−0.0101 (11)	0.0055 (10)	−0.0017 (11)
O6	0.0278 (12)	0.0271 (13)	0.0206 (11)	0.0027 (10)	0.0020 (9)	−0.0025 (10)
O7	0.0308 (12)	0.0277 (13)	0.0289 (11)	0.0000 (10)	−0.0100 (9)	0.0036 (11)
N1	0.0158 (13)	0.0200 (14)	0.0172 (12)	0.0023 (11)	−0.0016 (10)	−0.0032 (11)
N2	0.0164 (13)	0.0161 (14)	0.0171 (12)	0.0004 (10)	0.0018 (10)	−0.0037 (11)
C1	0.0259 (17)	0.0168 (16)	0.0189 (15)	0.0023 (14)	−0.0047 (12)	−0.0011 (14)
C2	0.0220 (16)	0.0193 (16)	0.0227 (16)	−0.0006 (13)	0.0002 (12)	0.0022 (14)
C3	0.0180 (16)	0.0227 (17)	0.0242 (16)	0.0007 (13)	−0.0032 (12)	−0.0044 (14)
C4	0.0187 (16)	0.0319 (19)	0.0167 (14)	0.0066 (14)	−0.0010 (12)	0.0004 (14)
C5	0.0230 (16)	0.0236 (18)	0.0160 (14)	0.0010 (14)	0.0025 (11)	0.0007 (14)
C6	0.0151 (14)	0.0199 (16)	0.0226 (15)	0.0003 (12)	−0.0034 (12)	−0.0034 (13)
C7	0.0148 (15)	0.0204 (16)	0.0224 (15)	0.0001 (13)	0.0002 (11)	0.0009 (14)
C8	0.0228 (15)	0.0164 (16)	0.0147 (14)	−0.0005 (13)	0.0029 (11)	−0.0033 (12)
C9	0.0294 (16)	0.0213 (16)	0.0142 (13)	0.0052 (15)	−0.0021 (11)	−0.0054 (14)
C10	0.0174 (15)	0.0215 (17)	0.0267 (17)	0.0018 (14)	−0.0025 (12)	−0.0098 (15)
C11	0.0198 (15)	0.0161 (15)	0.0234 (17)	−0.0040 (12)	0.0037 (12)	−0.0034 (13)
C12	0.0241 (17)	0.0182 (16)	0.0169 (15)	−0.0010 (14)	0.0009 (12)	−0.0027 (13)

Geometric parameters (Å, º) top

Cr1—O1	1.611 (2)	C3—H3	0.9500
Cr1—O2	1.620 (2)	C4—C5	1.380 (4)
Cr1—O3	1.624 (2)	C4—H4	0.9500
Cr1—O4	1.777 (2)	C5—H5	0.9500
Cr2—O5	1.612 (2)	C6—C7	1.511 (4)
Cr2—O7	1.613 (2)	C6—H6A	0.9900
Cr2—O6	1.624 (2)	C6—H6B	0.9900
Cr2—O4	1.790 (2)	C7—H7A	0.9900
N1—C1	1.337 (4)	C7—H7B	0.9900
N1—C5	1.353 (4)	C8—C9	1.376 (4)
N1—C6	1.491 (4)	C8—H8	0.9500
N2—C12	1.338 (4)	C9—C10	1.386 (4)
N2—C8	1.361 (4)	C9—H9	0.9500
N2—C7	1.491 (3)	C10—C11	1.392 (4)
C1—C2	1.379 (4)	C10—H10	0.9500
C1—H1	0.9500	C11—C12	1.387 (4)
C2—C3	1.385 (4)	C11—H11	0.9500
C2—H2	0.9500	C12—H12	0.9500
C3—C4	1.376 (5)

O1—Cr1—O2	110.01 (11)	N1—C5—C4	119.8 (3)
O1—Cr1—O3	110.60 (11)	N1—C5—H5	120.1
O2—Cr1—O3	110.15 (11)	C4—C5—H5	120.1
O1—Cr1—O4	110.43 (11)	N1—C6—C7	110.2 (2)
O2—Cr1—O4	105.93 (10)	N1—C6—H6A	109.6
O3—Cr1—O4	109.62 (11)	C7—C6—H6A	109.6
O5—Cr2—O7	111.07 (12)	N1—C6—H6B	109.6
O5—Cr2—O6	109.80 (13)	C7—C6—H6B	109.6
O7—Cr2—O6	109.78 (12)	H6A—C6—H6B	108.1
O5—Cr2—O4	109.08 (11)	N2—C7—C6	108.0 (2)
O7—Cr2—O4	107.35 (11)	N2—C7—H7A	110.1
O6—Cr2—O4	109.72 (10)	C6—C7—H7A	110.1
Cr1—O4—Cr2	127.96 (12)	N2—C7—H7B	110.1
C1—N1—C5	121.2 (3)	C6—C7—H7B	110.1
C1—N1—C6	119.4 (2)	H7A—C7—H7B	108.4
C5—N1—C6	119.3 (3)	N2—C8—C9	119.3 (3)
C12—N2—C8	122.4 (2)	N2—C8—H8	120.4
C12—N2—C7	119.0 (2)	C9—C8—H8	120.4
C8—N2—C7	118.7 (2)	C8—C9—C10	119.6 (3)
N1—C1—C2	120.7 (3)	C8—C9—H9	120.2
N1—C1—H1	119.7	C10—C9—H9	120.2
C2—C1—H1	119.7	C9—C10—C11	119.9 (3)
C1—C2—C3	119.0 (3)	C9—C10—H10	120.1
C1—C2—H2	120.5	C11—C10—H10	120.1
C3—C2—H2	120.5	C12—C11—C10	118.8 (3)
C4—C3—C2	119.6 (3)	C12—C11—H11	120.6
C4—C3—H3	120.2	C10—C11—H11	120.6
C2—C3—H3	120.2	N2—C12—C11	120.0 (3)
C3—C4—C5	119.6 (3)	N2—C12—H12	120.0
C3—C4—H4	120.2	C11—C12—H12	120.0
C5—C4—H4	120.2

O1—Cr1—O4—Cr2	62.94 (19)	C1—N1—C6—C7	−94.5 (3)
O2—Cr1—O4—Cr2	−177.98 (15)	C5—N1—C6—C7	86.8 (3)
O3—Cr1—O4—Cr2	−59.16 (19)	C12—N2—C7—C6	100.0 (3)
O5—Cr2—O4—Cr1	94.27 (18)	C8—N2—C7—C6	−79.6 (3)
O7—Cr2—O4—Cr1	−145.29 (16)	N1—C6—C7—N2	177.5 (2)
O6—Cr2—O4—Cr1	−26.04 (19)	C12—N2—C8—C9	0.7 (4)
C5—N1—C1—C2	1.1 (5)	C7—N2—C8—C9	−179.7 (3)
C6—N1—C1—C2	−177.6 (3)	N2—C8—C9—C10	−0.5 (5)
N1—C1—C2—C3	−0.8 (5)	C8—C9—C10—C11	0.0 (5)
C1—C2—C3—C4	−0.5 (5)	C9—C10—C11—C12	0.2 (5)
C2—C3—C4—C5	1.6 (5)	C8—N2—C12—C11	−0.5 (5)
C1—N1—C5—C4	0.0 (5)	C7—N2—C12—C11	179.9 (3)
C6—N1—C5—C4	178.7 (3)	C10—C11—C12—N2	0.1 (5)
C3—C4—C5—N1	−1.3 (5)

Experimental details

Crystal data
Chemical formula	(C₁₂H₁₄N₂)[Cr₂O₇]
M_r	402.25
Crystal system, space group	Monoclinic, P2₁
Temperature (K)	100
a, b, c (Å)	8.2882 (4), 9.0722 (4), 10.0179 (5)
β (°)	91.882 (1)
V (Å³)	752.86 (6)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	1.48
Crystal size (mm)	0.22 × 0.15 × 0.15

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2005)
T_min, T_max	0.737, 0.808
No. of measured, independent and observed [I > 2σ(I)] reflections	5446, 2628, 2546
R_int	0.025
(sin θ/λ)_max (Å⁻¹)	0.602

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.027, 0.067, 1.04
No. of reflections	2628
No. of parameters	209
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.47, −0.21
Absolute structure	Flack (1983), 1163 Friedel pairs
Absolute structure parameter	0.510 (19)

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008) and enCIFer (Allen et al., 2004).

Acknowledgements

Support of this investigation by Ferdowsi University of Mashhad is gratefully acknowledged.

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