[(4E,11E)-5,7,12,14-Tetra­benzyl-7,14-dimethyl-1,4,8,11-tetra­aza­cyclo­tetra­deca-4,11-diene]copper(II) bis(per­chlorate)

Tapashi G Roy; Saroj K S Hazari; Babul C Nath; Seik Weng Ng; Edward R T Tiekink

doi:10.1107/S1600536811042796

. 2011 Oct 22;67(Pt 11):m1581–m1582. doi: 10.1107/S1600536811042796

[(4E,11E)-5,7,12,14-Tetrabenzyl-7,14-dimethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene]copper(II) bis(perchlorate)

Tapashi G Roy ^a,^‡, Saroj K S Hazari ^a, Babul C Nath ^a, Seik Weng Ng ^b,^c, Edward R T Tiekink ^b,^*

PMCID: PMC3246995 PMID: 22219815

Abstract

The complete cation in the title compound, [Cu(C₄₀H₄₈N₄)](ClO₄)₂, is generated by the operation of a crystallographic centre of inversion. The Cu^II ion exists in a tetragonally distorted trans-N₄O₂ coordination geometry defined by the four N atoms of the macrocyclic ligand and two weakly bound perchlorate-O atoms from two anions. The N—H atoms form intramolecular N—H⋯O(perchlorate) hydrogen bonds. Disorder was resolved in the –CH₂–NH– portion of the macrocycle with the major component having a site-occupancy factor of 0.570 (6).

Related literature

For background to the synthesis, characterization, kinetic studies and biological activities of 14-membered methyl-substituted tetraazamacrocyclic ligands, their N-substituted derivatives and their metal complexes, see: Hazari et al. (2008 ▶).

Experimental

Crystal data

[Cu(C₄₀H₄₈N₄)](ClO₄)₂
M _r = 847.26
Monoclinic,
a = 10.1170 (3) Å
b = 16.6017 (4) Å
c = 11.9910 (3) Å
β = 108.818 (3)°
V = 1906.35 (9) Å³
Z = 2
Mo Kα radiation
μ = 0.77 mm⁻¹
T = 100 K
0.30 × 0.25 × 0.20 mm

Data collection

Agilent Technologies SuperNova Dual diffractometer with Atlas detector
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2010 ▶) T _min = 0.792, T _max = 1.000
9806 measured reflections
4253 independent reflections
3707 reflections with I > 2σ(I)
R _int = 0.024

Refinement

R[F ² > 2σ(F ²)] = 0.059
wR(F ²) = 0.145
S = 1.08
4253 reflections
251 parameters
15 restraints
H-atom parameters constrained
Δρ_max = 0.64 e Å⁻³
Δρ_min = −1.08 e Å⁻³

Data collection: CrysAlis PRO (Agilent, 2010 ▶); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 (Farrugia, 1997 ▶) and DIAMOND (Brandenburg, 2006 ▶); software used to prepare material for publication: publCIF (Westrip, 2010 ▶).

Supplementary Material

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536811042796/hb6449sup1.cif

e-67-m1581-sup1.cif^{(26.3KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536811042796/hb6449Isup2.hkl

e-67-m1581-Isup2.hkl^{(208.4KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Selected bond lengths (Å).

Cu—N1	2.032 (4)
Cu—N2	1.977 (2)
Cu—O1	2.662 (2)

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Table 2. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯O1ⁱ	0.88	2.39	2.940 (5)	121
N1′—H1′⋯O2	0.88	2.29	3.104 (4)	153

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Symmetry code: (i) Inline graphic .

Acknowledgments

The authors are grateful to the Bangladesh Ministry of Science, and Information and Communication Technology, Bangladesh, for awarding a research grant to TGR and to the University of Malaya for support of the crystallographic facility.

supplementary crystallographic information

Comment

The title complex, (I), was investigated in continuation of studies of the synthesis, characterization and biological activities of methyl substituted tetraazamacrocyclic ligands and their metal complexes (Hazari et al., 2008).

The structure of (I), Fig. 1, features a tetragonally distorted N₄O₂ donor set about a Cu^II atom, Table 1. The N-donor atoms are derived from the (4E,11E)-5,7,12,14-tetrabenzyl-7,14-dimethyl- 1,4,8,11-tetraazacyclotetradeca-4,11-diene macrocyclic ligand, and the O-donors are derived from two perchlorate anions. The complex is centrosymmetric. A C-meso, N-meso configuration is found in (I). With reference to the six-membered chelate ring, the benzyl and methyl groups equatorially and axially orientated, respectively. The dihedral angle formed between the benzene rings is 44.22 (16) Å. Each N—H atom of the disordered —CH₂—NH— residue forms an intramolecular N—H···O hydrogen bond with a perchlorate-O atom, Table 2, i.e. to either side of the CuN₄ plane. The competition between the formation of these alternate hydrogen bonds provides a rationale for the observed disorder.

Experimental

The macrocyclic ligand as its hydroperchloric acid salt (0.783 g, 1.0 mmol) was suspended in methanol (20 ml). Copper(II) perchlorate hexahydrate (0.370 g, 1.0 mmol) was dissolved in methanol (30 ml) and then was mixed with the suspension of the ligand salt. The mixture was refluxed for 3 h and a clear violet solution evolved. The solution was filtered and kept at room temperature. After 24 h, violet crystals of the complex were observed. The crystals were separated by filtration, washed with dry ethanol, followed by diethylether and dried in a vacuum desiccator over silica gel. M.pt. 510–512 K. Yield 45%. Anal. Calc. for [Cu(C₄₀H₄₈N₄)](ClO₄)₂ C, 56.77; H, 5.56; N, 6.62; Cu, 7.51%. Found: C, 56.56; H, 5.53; N, 6.75; Cu, 7.35%. FT—IR (KBr, cm^-1) 3220 ν(N—H), 3028 ν(Ar—H), 2980 ν(C—H), 1650 ν(C═N), 1375 ν(CH₃), 1185 ν(C—C), 1126 ν(ClO₄), 710 ν(ArC—H)), 488 ν(Cu—N). The light-purple prisms were prepared by slow evaporation of a methanol solution of the complex.