Crystal structure of 4-{2-[4-(di­methyl­amino)­phen­yl]diazen-1-yl}-1-methyl­pyridinium iodide

Katherine Chulvi; Ana Costero; Luis E Ochando; Pablo Gaviña

doi:10.1107/S2056989015023646

. 2015 Dec 19;71(Pt 12):o1069–o1070. doi: 10.1107/S2056989015023646

Crystal structure of 4-{2-[4-(dimethylamino)phenyl]diazen-1-yl}-1-methylpyridinium iodide

Katherine Chulvi ^a, Ana Costero ^a,^*, Luis E Ochando ^a, Pablo Gaviña ^a

PMCID: PMC4719983 PMID: 26870502

Abstract

The molecular geometry of the ionic title compound, C₁₄H₁₇N₄ ⁺·I⁻ or DAZOP⁺·I⁻, is essentially featureless. Regarding the crystal structure, in addition to the obvious cation–anion Coulombic interactions, the packing is mostly directed by non-covalent interactions involving both ring systems, as well as the iodide anion. It consists of cationic molecules aligned along [101] and disposed in an antiparallel fashion while linked into π-bonded dimeric entities by a stacking contact involving symmetry-related phenyl rings, with a centroid–centroid distance of 3.468 (3) Å and a slippage of 0.951 Å. The dimers are, in addition, sustained by a number of C—H⋯I and I⋯π (I⋯centroid = 3.876 Å) interactions involving the anion. Finally, interdimeric contacts are of the C—H⋯I and C—H⋯π types.

Keywords: crystal structure, [DAZOP⁺][I⁻], NLO, dye, π–π interaction, C—H⋯ π interactions, I⋯π interaction

Related literature

For the synthesis of precursors, see: Li et al. (1995 ▸). For spectroscopic properties of the title compound, see: Gonbeau et al. (1999 ▸). For general infomation on non-linear optical materials, see: Coradin et al. (1997 ▸); Mestechkin (2001 ▸); Nunzi et al. (2008 ▸). For general infomation on new photonic materials, see: Yu et al. (2013 ▸). For related structures, see: Cristian et al. (2004 ▸); Evans et al. (2001 ▸); Xu et al. (2012 ▸). graphic file with name e-71-o1069-scheme1.jpg

Experimental

Crystal data

C₁₄H₁₇N₄ ⁺·I⁻
M _r = 368.21
Monoclinic,
a = 18.0508 (14) Å
b = 7.2790 (5) Å
c = 11.3760 (9) Å
β = 98.929 (7)°
V = 1476.60 (19) Å³
Z = 4
Mo Kα radiation
μ = 2.16 mm⁻¹
T = 296 K
0.14 × 0.08 × 0.03 mm

Data collection

Agilent Xcalibur Sapphire3 Gemini diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2009 ▸) T _min = 0.908, T _max = 1.000
5694 measured reflections
2591 independent reflections
1642 reflections with I > 2σ(I)
R _int = 0.048

Refinement

R[F ² > 2σ(F ²)] = 0.035
wR(F ²) = 0.065
S = 0.78
2591 reflections
175 parameters
132 restraints
H-atom parameters constrained
Δρ_max = 1.00 e Å⁻³
Δρ_min = −0.51 e Å⁻³

Data collection: CrysAlis PRO (Agilent, 2009 ▸); cell refinement: CrysAlis PRO); data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▸); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2015 ▸); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012 ▸); software used to prepare material for publication: WinGX (Farrugia, 2012 ▸).

Supplementary Material

Crystal structure: contains datablock(s) I, shelx. DOI: 10.1107/S2056989015023646/bg2576sup1.cif

e-71-o1069-sup1.cif^{(267.5KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S2056989015023646/bg2576Isup2.hkl

e-71-o1069-Isup2.hkl^{(207.5KB, hkl)}

Click here for additional data file.^{(5.6KB, cml)}

Supporting information file. DOI: 10.1107/S2056989015023646/bg2576Isup3.cml

Click here for additional data file.^{(2.4MB, tif)}

x y z . DOI: 10.1107/S2056989015023646/bg2576fig1.tif

The molecular structure of (I),showing the atom-labelling scheme as well as the dimer formation. Displacement ellipsoids drawn at the 50% probability level. Symmetry codes: (i): 1 − x, 1 − y, 2 − z.

CCDC reference: 1441443

Additional supporting information: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

Cg2 is the centroid of the C12–C16/N17 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C1—H1A⋯I1ⁱ	0.96	3.09	4.042 (6)	173
C2—H2A⋯I1ⁱ	0.96	3.15	4.102 (5)	169
C15—H15A⋯I1ⁱⁱ	0.93	2.99	3.907 (5)	171
C7—H7A⋯Cg2ⁱⁱⁱ	0.93	2.71	3.505 (5)	143

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Symmetry codes: (i) Inline graphic ; (ii) ; (iii) .

supplementary crystallographic information

S1. Chemical context

Over the years, the spectroscopic properties of 4-[2-(4-dimethylaminophenyl)azo]-1-methylpyridinium iodide ([DAZOP⁺][I⁻]) have been widely studied (Gonbeau et al., 1999). This dye with donor-acceptor character, belongs to the group of the so-called non-linear optical chromophores (NLO-phore) that are able to form J-type aggregates (Coradin et al., 1997; Mestechkin, 2001; Nunzi et al., 2008). The crystal structures of this kind of NLO dyes are a topic of interest in this context and also for studies related to the solvatochromic properties of these dyes in hydrogen-bond-donor (HBD) and hydrogen-bond-acceptor (HBA) solvents. Very recently, new three-dimensional materials based on organic metalorganic frameworks (MOFs) with the capability to encapsulate dyes have been developed. All of these progress are aimed to the new photonic materials and devices design (Yu et al., 2013).

S2. Structural commentary

The title ionic compound [DAZOP⁺][I⁻] (I) crystallizes in the monoclinic S·G. P21/c, and presents one single molecule in the asymmetric unit. The molecular geometry, presented in Fig. 1, is essentially featureless.

S3. Supramolecular features

In addition to the obvious cation-anion coulombian interactions, the crystal packing is mostly directed by non covalent interactions involving the ring systems Cg1 (C4->C9) and Cg2 (C12->C16,N17, as well as the Iodine anion.

It consists of cationic molecules aligned along the [101] direction and disposed in an antiparallel fashion while linked into π bonded dimeric entities (Fig. 1) by a stacking contact involving Cg2 and Cg2ⁱ [(i): 1 − x,1 − y,2 − z)]), with d(Cg···Cg) = 3.468 (3) Å and a slippage of 0.951 Å. The dimer is in addition sustained by a number of interactions involving I1, viz (a) I···Cg1ⁱ, with d(I···Cg)= 3.876 Å, (b) C1—H1A···I1ⁱ, with d(H···I) = 3.09 Å, <C—H···I> = 173°, (c) C2—H2A···I1ⁱ, with d(H···I) = 3.15 Å, <C—H···I> = 169°. The remaining non-covalent interactions serve to link these dimers with each other, either directly, viz., through a C7—H7···Cg2iii [(iii): 1 − x,1/2 + y,3/2 − z] contact, with d(H···Cg) = 2.71 Å, <C—H···Cg> = 143° or mediated by the external iodine (viz., C15—H15.. I1ⁱⁱ [(ii): x,3/2 − y,-1/2 + z], d(H···I): 2.99 Å; <C—H···I> = 171°).

S4. Database survey

There are in the literature a lot of crystal structures derived from DAZOP but none with iodine as counter ion. The most similar to (I) is the one with CSD code (Allen, 2002) HANKUD (Cristian et al., 2004) which was solved using powder data and contains a molecule of hexafluorophosphate as counter ion. Thus although the molecules are practically the same, the differences between both structures are significant, mainly due to the absence of π–π interactions in HANKUD. Some similar structures of (DAZOP⁺) coordinated with metalorganic ions can be found in the CSD, viz., IFAHAY (J. S. O. Evans et al., 2001), RARTEL, RARTIP, RARTOV, (Xu et al., 2012), etc.

S5. Synthesis and crystallization

Benzenamine, N,N-dimethyl-4- (4-pyridinylazo)- was obtained as described in the literature (Li et al., 1995). It was then dissolved in acetonitrile and stirred while an excess of methyl iodide was added dropwise. The resultant mixture was refluxed for 3 h. After that, the orange precipitated obtained was further purified by column chromatography (1:4, methanol/ethyl acetate) with a yield of 59%. Single crystals were obtained by slow evaporation from a methanol solution using a Petri dish.

S6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 1