rac-Dichlorido[3-eth­oxy-3-(1-ethyl-1H-benzimidazol-2-yl)-2,3-dihydro-1H-pyrrolo­[1,2-a]benzimidazole]­copper(II)

Stibrany, R.T.; Potenza, J.A.

doi:10.1107/S1600536812051641

Volume 69
Part 2
Pages m92-m93
February 2013

Received 19 December 2012
Accepted 21 December 2012
Online 9 January 2013

Key indicators
Single-crystal X-ray study
T = 294 K
Mean (C-C) = 0.005 Å
R = 0.044
wR = 0.124
Data-to-parameter ratio = 15.6
Details

rac-Dichlorido[3-ethoxy-3-(1-ethyl-1H-benzimidazol-2-yl)-2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole]copper(II)

Robert T. Stibrany ^a ^* and Joseph A. Potenza ^a

^aDepartment of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, 610 Taylor Road, Piscataway, New Jersey 08854, USA
Correspondence e-mail: DZSquared@aol.com

The title complex, [CuCl₂(C₂₁H₂₂N₄O)], contains a bis(benzimidazole) unit with a chiral bridgehead C atom that forms part of a tetrahydropyrrole ring fused to one of the benzimidazoles. The chelate angle is 90.45 (9)° and the dihedral angle between the essentially planar benzimidazole fragments is 26.68 (9)°. The Cu^II coordination geometry lies approximately midway between tetrahedral and square planar. Overall, each chiral molecule contains six fused rings, and a racemic mixture is formed with symmetry-related enantiomers. In the crystal, C-H [pi] and C-HCl interactions link molecules into a supramolecular chain along the a-axis direction.

Related literature

For ¹⁹F NMR studies of related compounds, see: Stibrany (2003). For polymerization studies, see: Stibrany et al. (2003). For their use as agents to study electron transfer, see: Knapp et al. (1990). For related structures, see: Baugh et al. (2006); Stibrany (2009); Stibrany et al. (2002, 2004); Stibrany & Potenza (2006, 2008). For calculation of the four-coordination geometry, see: Yang et al. (2007).

Experimental

Crystal data

[CuCl₂(C₂₁H₂₂N₄O)]
M_r = 480.87
Triclinic, $[P \overline 1]$
a = 8.9409 (17) Å
b = 9.5209 (18) Å
c = 14.323 (3) Å
= 106.973 (4)°
= 92.373 (4)°
= 113.778 (4)°
V = 1049.3 (3) Å³
Z = 2
Mo K radiation
= 1.32 mm^-1
T = 294 K
0.43 × 0.23 × 0.06 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2000; Blessing, 1995) T_min = 0.771, T_max = 1.00
10062 measured reflections
4126 independent reflections
3380 reflections with I > 2(I)
R_int = 0.027

Refinement

R[F² > 2(F²)] = 0.044
wR(F²) = 0.124
S = 1.00
4126 reflections
264 parameters
1 restraint
H-atom parameters constrained
_max = 0.90 e Å^-3
_min = -0.29 e Å^-3

Table 1
Selected geometric parameters (Å, °)

Cu-N23	1.993 (2)
Cu-N13	2.005 (2)
Cu-Cl1	2.2169 (9)
Cu-Cl2	2.2198 (9)

N23-Cu-N13	90.45 (9)
N23-Cu-Cl1	141.12 (8)
N13-Cu-Cl1	94.14 (7)
N23-Cu-Cl2	100.17 (7)
N13-Cu-Cl2	143.67 (8)
Cl1-Cu-Cl2	98.64 (4)

Table 2
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C11/C13-C17 phenyl ring.

D-HA	D-H	HA	DA	D-HA
C4-H4BCg1ⁱ	0.96	2.99	3.910 (5)	160
C17-H17Cl1ⁱⁱ	0.93	2.78	3.694 (4)	169
Symmetry codes: (i) -x, -y+2, -z; (ii) x+1, y, z.

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: TK5184 ).

References

Baugh, L. S., Sissano, J. A., Kacker, S., Berluche, E., Stibrany, R. T., Schulz, D. N. & Rucker, S. P. (2006). J. Polymer Sci. Part A: Polymer Chem. 44, 1817-1840.
Blessing, R. H. (1995). Acta Cryst. A51, 33-38.
Bruker (2000). SAINT, SMART and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.
Burnett, M. N. & Johnson, C. K. (1996). ORTEPIII Report ORNL-6895. Oak Ridge National Laboratory, Tennessee, USA.
Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.
Knapp, S., Keenan, T. P., Zhang, X., Fikar, R., Potenza, J. A. & Schugar, H. J. (1990). J. Am. Chem. Soc. 112, 3452-3464.
Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.
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Stibrany, R. T. (2009). J. Chem. Crystallogr. 39, 719-722.
Stibrany, R. T., Lobanov, M. V., Schugar, H. J. & Potenza, J. A. (2004). Inorg. Chem. 43, 1472-1480.
Stibrany, R. T. & Potenza, J. A. (2006). Private communication (refcode TEVJAG). CCDC, Cambridge, England.
Stibrany, R. T. & Potenza, J. A. (2008). Acta Cryst. C64, m213-m216.
Stibrany, R. T., Schugar, H. J. & Potenza, J. A. (2002). Acta Cryst. E58, o1142-o1144.
Stibrany, R. T., Schulz, D. N., Kacker, S., Patil, A. O., Baugh, L. S., Rucker, S. P., Zushma, S., Berluche, E. & Sissano, J. A. (2003). Macromolecules, 36, 8584-8586.
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