1,6-Bis[(2,2′:6′,2′′-terpyridin-4′-yl)­oxy]hexa­ne

Nikolayenko, V.I.; Akerman, M.P.; Grimmer, C.D.; Reddy, D.

doi:10.1107/S1600536812029017

organic compounds

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ISSN: 2056-9890

Volume 68| Part 7| July 2012| Pages o2272-o2273

https://doi.org/10.1107/S1600536812029017

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1,6-Bis[(2,2′:6′,2′′-terpyridin-4′-yl)oxy]hexane

Varvara I. Nikolayenko,^a ^* Matthew P. Akerman,^a Craig D. Grimmer ^a and Desigan Reddy ^a

^aUniversity of KwaZulu-Natal, School of Chemistry and Physics, Private Bag X01, Scottsville 3209, Pietermaritzburg, South Africa
^*Correspondence e-mail: 207513620@stu.ukzn.ac.za

(Received 14 June 2012; accepted 26 June 2012; online 30 June 2012)

The molecule of the title compound, C₃₆H₃₂N₆O₂, lies about an inversion center, located at the mid-point of the central C—C bond of the diether bridge. The terminal pyridine rings form dihedral angles of 4.67 (7) and 26.23 (7)° with the central ring. In the crystal, weak C—H⋯N and C—H⋯O interactions link the molecules into a three-dimensional network.

Related literature

For the structure of the unsubstituted 2,2′:6′,2"-terpyridine, see: Bessel et al. (1992 ). For the structure of the precursor to the title compound, 4′-chloro-2,2′:6′,2"-terpyridine, see: Beves et al. (2006 ). For the structure of the 1,4-bis[(2,2′:6′,2"-terpyridin-4′-yl)oxy]-butane, see: Akerman et al. (2011 ). For a full review of functionalized 2,2′:6′,2"-terpyridine complexes, see: Fallahpour (2003 ); Heller & Schubert (2003 ). For a comprehensive summary of platinum(II) terpyridine complexes, see: Newkome et al. (2008 ). For the structure of bis(2,2′:6′,2"-terpyridyl)ether, see: Constable et al. (1995 ). For the structure of related bis(terpyridine) compounds, linked by an alkoxy spacer, see: Constable et al. (2006 ). For the synthetic procedure, see: Constable et al. (2005 ); Van der Schilden (2006 ).

Experimental

Crystal data

C₃₆H₃₂N₆O₂
M_r = 580.7
Orthorhombic, P b c a
a = 15.139 (5) Å
b = 11.428 (5) Å
c = 16.760 (5) Å
V = 2899.6 (18) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 100 K
0.40 × 0.20 × 0.20 mm

Data collection

Oxford Diffraction Xcalibur 2 CCD diffractometer
Absorption correction: multi-scan (Blessing, 1995 ) T_min = 0.967, T_max = 0.983
20354 measured reflections
2859 independent reflections
2098 reflections with I > 2σ(I)
R_int = 0.064

Refinement

R[F² > 2σ(F²)] = 0.038
wR(F²) = 0.100
S = 0.94
2859 reflections
199 parameters
H-atom parameters constrained
Δρ_max = 0.17 e Å⁻³
Δρ_min = −0.26 e Å⁻³

Table 1
Short intermolecular contacts (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C15—H15⋯Oⁱ	0.95	2.65	3.575 (2)	164
C1—H1⋯N3ⁱⁱ	0.95	2.71	3.654 (2)	174
C4—H4⋯N1ⁱⁱⁱ	0.95	2.65	3.402 (2)	136
C2—H2⋯Oⁱⁱ	0.95	2.69	3.627 (2)	168
Symmetry codes: (i) $[-x, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]$ ; (ii) $[-x+{\script{1\over 2}}, -y, z-{\script{1\over 2}}]$ ; (iii) $[-x+{\script{1\over 2}}, y+{\script{1\over 2}}, z]$ .

Data collection: CrysAlis CCD (Oxford Diffraction, 2008 $[Oxford Diffraction (2008). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]$ ); cell refinement: CrysAlis CCD; data reduction: CrysAlis RED (Oxford Diffraction, 2008 $[Oxford Diffraction (2008). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]$ ); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1999 ); software used to prepare material for publication: publCIF (Westrip, 2010 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536812029017/yk2063sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536812029017/yk2063Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536812029017/yk2063Isup3.cml

checkCIF report

Comment top

The title compound is the second in a series of ligands developed in an effort to harness multifunctional activity. Coordination of these ligands to platinum(II) should enable covalent binding of DNA through both metal centres, thus increasing the number of adducts formed. Furthermore the presence of the flexible diol derived linkage will provide the complex with the potential to engage in long range interactions with DNA.

The ligand crystallized in the orthorhombic space group Pbca, with a half molecule in the asymmetric unit and Z = 4. Crystallographically imposed inversion symmetry relates two halves of the ligand. The inversion center is located at the mid-point of the diol linkage. The three pyridine rings adopt a trans, trans conformation. The same configuration is observed in the parent 4'-chloro-2,2': 6',2''- terpyridine (Beves et al., 2006) and is a common feature of uncoordinated terpyridine ligands in general (Akerman et al., 2011; Bessel et al., 1992).

The central pyridine ring of the terpyridine fragment lie in the same plane as the bridging chain. The terminal pyridine rings are, however, canted relative to the central ring. The C7–C6–C5–N1 torsion angle is -25.8 (2)°, while the C9–C10–C11–N3 torsion angle is 4.9 (2)° (Fig. 1). The large torsion angle formed by one of terminal pyridine groups with the central ring is seemingly to allow for interaction between the pyridine N1 atom and the hydrogen atom H4 of an adjacent molecule, with the distance of 2.65 Å. There are also other short contacts C—H···O and C—H···N, ranging from 2.65 to 2.71 Å. These contacts link the molecules into a herringbone pattern (Figure 2). There is no indication of meaningful π··· π or C–H··· π interactions in the lattice, which are often observed in terpyridine structures (Beves et al. 2006).

Related literature top

For the structure of the unsubstituted 2,2':6',2"-terpyridine, see: Bessel et al. (1992). For the structure of the precursor to the title compound, 4'-chloro-2,2':6',2"-terpyridine, see: Beves et al. (2006). For the structure of the 1,4-bis[(2,2':6',2"-terpyridin-4'-yl)oxy]-butane, see: Akerman et al. (2011). For a full review of functionalized 2,2':6',2"-terpyridine complexes, see: Fallahpour (2003); Heller & Schubert (2003). For a comprehensive summary of platinum(II) terpyridine complexes, see: Newkome et al. (2008). For the structure of bis(2,2':6',2"-terpyridyl)ether, see: Constable et al. (1995). For the structure of related bis(terpyridine) compounds, linked by an alkoxy spacer, see: Constable et al. (2006). For the synthetic procedure, see: Constable et al. (2005); Van der Schilden (2006).

Experimental top

The title compound was prepared by an adaptation of a previously described method (Van der Schilden, 2006; Constable et al., 2005). Hexanediol (1.13 mmol) was added to a suspension of ground potassium hydroxide (6.69 mmol) in DMSO (30 ml). The solution was heated to reflux for 1 h after which 4'-chloro-2,2':6',2''-terpyridine (2.23 mmol) was added. The mixture was again brought to reflux for an additional 24 h. After cooling to room temperature, the brown mixture was added to cold water (100 ml). The resulting off-white precipitate was filtered, rinsed with cold ethanol and air dried. Single crystals were grown by slow liquid diffusion of n-hexane into a chloroform solution of the compound.

Structure description top

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2008); cell refinement: CrysAlis CCD (Oxford Diffraction, 2008); data reduction: CrysAlis RED (Oxford Diffraction, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1999); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top

	Fig. 1. The molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. Intermolecular C—H···O and C—H···N contacts responsible for the three-dimensional network in crystals of the title compound, viewed down the b axis.

1,6-Bis[(2,2':6',2''-terpyridin-4'-yl)oxy]hexane top

Crystal data top

C₃₆H₃₂N₆O₂	F(000) = 1224
M_r = 580.7	D_x = 1.330 Mg m⁻³
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 2098 reflections
a = 15.139 (5) Å	θ = 3.2–26.0°
b = 11.428 (5) Å	µ = 0.09 mm⁻¹
c = 16.760 (5) Å	T = 100 K
V = 2899.6 (18) Å³	Needle, colourless
Z = 4	0.40 × 0.20 × 0.20 mm

Data collection top

Oxford Diffraction Xcalibur 2 CCD diffractometer	2859 independent reflections
Radiation source: fine-focus sealed tube	2098 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.064
ω scans at fixed θ angles	θ_max = 26.1°, θ_min = 3.2°
Absorption correction: multi-scan (Blessing, 1995)	h = −18→18
T_min = 0.967, T_max = 0.983	k = −12→14
20354 measured reflections	l = −20→20

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)] = 0.038	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.100	H-atom parameters constrained
S = 0.94	w = 1/[σ²(F_o²) + (0.0644P)² + 0.P] where P = (F_o² + 2F_c²)/3
2859 reflections	(Δ/σ)_max = 0.001
199 parameters	Δρ_max = 0.17 e Å⁻³
0 restraints	Δρ_min = −0.26 e Å⁻³

Crystal data top

C₃₆H₃₂N₆O₂	V = 2899.6 (18) Å³
M_r = 580.7	Z = 4
Orthorhombic, Pbca	Mo Kα radiation
a = 15.139 (5) Å	µ = 0.09 mm⁻¹
b = 11.428 (5) Å	T = 100 K
c = 16.760 (5) Å	0.40 × 0.20 × 0.20 mm

Data collection top

Oxford Diffraction Xcalibur 2 CCD diffractometer	2859 independent reflections
Absorption correction: multi-scan (Blessing, 1995)	2098 reflections with I > 2σ(I)
T_min = 0.967, T_max = 0.983	R_int = 0.064
20354 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.038	0 restraints
wR(F²) = 0.100	H-atom parameters constrained
S = 0.94	Δρ_max = 0.17 e Å⁻³
2859 reflections	Δρ_min = −0.26 e Å⁻³
199 parameters

Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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
C1	0.33229 (9)	0.02089 (12)	0.29739 (9)	0.0207 (3)
H1	0.3600	−0.0452	0.2738	0.025*
C2	0.34439 (10)	0.13004 (12)	0.26216 (9)	0.0251 (4)
H2	0.3790	0.1379	0.2152	0.030*
C3	0.30541 (10)	0.22649 (12)	0.29648 (9)	0.0242 (3)
H3	0.3124	0.3019	0.2734	0.029*
C4	0.25569 (9)	0.21180 (12)	0.36541 (8)	0.0203 (3)
H4	0.2288	0.2770	0.3907	0.024*
C5	0.24615 (9)	0.10061 (12)	0.39646 (8)	0.0168 (3)
C6	0.19174 (9)	0.07961 (12)	0.46867 (8)	0.0165 (3)
C7	0.15172 (9)	−0.02860 (12)	0.48099 (8)	0.0176 (3)
H7	0.1608	−0.0915	0.4448	0.021*
C8	0.09834 (9)	−0.04198 (12)	0.54744 (8)	0.0171 (3)
C9	0.08764 (9)	0.05263 (12)	0.59918 (8)	0.0181 (3)
H9	0.0506	0.0462	0.6447	0.022*
C10	0.13161 (9)	0.15523 (12)	0.58311 (8)	0.0169 (3)
C11	0.12409 (9)	0.25867 (12)	0.63712 (8)	0.0183 (3)
C12	0.16340 (10)	0.36471 (12)	0.61690 (9)	0.0210 (3)
H12	0.1964	0.3725	0.5690	0.025*
C13	0.15333 (10)	0.45889 (13)	0.66836 (9)	0.0249 (4)
H13	0.1788	0.5327	0.6559	0.030*
C14	0.10571 (10)	0.44385 (13)	0.73784 (9)	0.0251 (4)
H14	0.0972	0.5071	0.7738	0.030*
C15	0.07083 (10)	0.33492 (13)	0.75376 (9)	0.0248 (4)
H15	0.0398	0.3245	0.8025	0.030*
C16	0.06992 (9)	−0.24153 (11)	0.51510 (9)	0.0194 (3)
H16A	0.1330	−0.2642	0.5175	0.023*
H16B	0.0554	−0.2212	0.4592	0.023*
C17	0.01309 (10)	−0.34175 (11)	0.54245 (9)	0.0197 (3)
H17A	−0.0499	−0.3192	0.5396	0.024*
H17B	0.0272	−0.3612	0.5986	0.024*
C18	0.02948 (9)	−0.44830 (11)	0.48956 (9)	0.0194 (3)
H18A	0.0192	−0.4263	0.4332	0.023*
H18B	0.0920	−0.4722	0.4948	0.023*
N1	0.28336 (8)	0.00494 (10)	0.36295 (7)	0.0196 (3)
N2	0.18298 (8)	0.17077 (9)	0.51806 (7)	0.0176 (3)
N3	0.07781 (8)	0.24306 (10)	0.70493 (7)	0.0205 (3)
O	0.05447 (6)	−0.14203 (8)	0.56613 (6)	0.0204 (2)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0226 (8)	0.0216 (8)	0.0178 (7)	−0.0008 (6)	0.0034 (6)	−0.0049 (6)
C2	0.0274 (9)	0.0297 (9)	0.0183 (8)	−0.0054 (6)	0.0059 (6)	−0.0001 (7)
C3	0.0310 (8)	0.0187 (7)	0.0230 (8)	−0.0061 (6)	0.0010 (7)	0.0019 (6)
C4	0.0230 (8)	0.0180 (7)	0.0198 (7)	−0.0019 (6)	−0.0002 (6)	−0.0025 (6)
C5	0.0176 (7)	0.0190 (7)	0.0137 (7)	−0.0016 (6)	−0.0026 (6)	−0.0010 (6)
C6	0.0175 (7)	0.0164 (7)	0.0155 (7)	0.0008 (5)	−0.0018 (6)	0.0011 (6)
C7	0.0202 (8)	0.0157 (7)	0.0168 (7)	0.0005 (5)	−0.0006 (6)	−0.0014 (6)
C8	0.0175 (7)	0.0149 (7)	0.0189 (7)	−0.0013 (5)	−0.0029 (6)	0.0024 (6)
C9	0.0203 (8)	0.0199 (7)	0.0141 (7)	0.0011 (6)	−0.0001 (6)	0.0000 (6)
C10	0.0173 (7)	0.0184 (7)	0.0150 (7)	0.0019 (5)	−0.0017 (6)	0.0000 (6)
C11	0.0185 (7)	0.0194 (7)	0.0172 (7)	0.0015 (6)	−0.0016 (6)	−0.0023 (6)
C12	0.0228 (8)	0.0210 (8)	0.0191 (8)	−0.0016 (6)	0.0006 (6)	−0.0015 (6)
C13	0.0268 (8)	0.0179 (8)	0.0299 (8)	−0.0012 (6)	−0.0026 (7)	−0.0035 (6)
C14	0.0265 (8)	0.0243 (8)	0.0246 (8)	0.0020 (6)	−0.0016 (7)	−0.0090 (7)
C15	0.0251 (8)	0.0284 (8)	0.0209 (8)	0.0028 (7)	0.0015 (7)	−0.0047 (7)
C16	0.0237 (7)	0.0146 (7)	0.0198 (7)	−0.0008 (6)	0.0020 (6)	−0.0018 (6)
C17	0.0228 (8)	0.0164 (7)	0.0199 (8)	−0.0006 (6)	0.0014 (6)	−0.0002 (6)
C18	0.0212 (8)	0.0163 (7)	0.0208 (7)	−0.0008 (6)	0.0023 (6)	−0.0004 (6)
N1	0.0215 (6)	0.0190 (6)	0.0184 (6)	0.0003 (5)	0.0008 (5)	−0.0016 (5)
N2	0.0205 (6)	0.0165 (6)	0.0159 (6)	0.0007 (5)	−0.0010 (5)	−0.0004 (5)
N3	0.0226 (6)	0.0214 (6)	0.0175 (6)	0.0001 (5)	0.0023 (5)	−0.0025 (5)
O	0.0262 (6)	0.0146 (5)	0.0203 (5)	−0.0041 (4)	0.0044 (4)	−0.0012 (4)

Geometric parameters (Å, º) top

C1—N1	1.3374 (18)	C10—N2	1.3508 (18)
C1—C2	1.392 (2)	C10—C11	1.4934 (19)
C2—C3	1.377 (2)	C11—N3	1.3467 (18)
C3—C4	1.389 (2)	C11—C12	1.391 (2)
C4—C5	1.380 (2)	C12—C13	1.388 (2)
C5—N1	1.3527 (18)	C13—C14	1.380 (2)
C5—C6	1.4833 (19)	C14—C15	1.378 (2)
C6—N2	1.3374 (18)	C15—N3	1.3354 (18)
C6—C7	1.3917 (19)	C16—O	1.4422 (17)
C7—C8	1.3845 (19)	C16—C17	1.5031 (19)
C8—O	1.3581 (17)	C17—C18	1.527 (2)
C8—C9	1.395 (2)	C18—C18ⁱ	1.521 (3)
C9—C10	1.374 (2)

N1—C1—C2	122.88 (13)	N2—C10—C11	115.45 (12)
C3—C2—C1	118.96 (14)	C9—C10—C11	121.29 (12)
C2—C3—C4	118.91 (13)	N3—C11—C12	122.87 (13)
C5—C4—C3	118.73 (13)	N3—C11—C10	116.54 (12)
N1—C5—C4	122.98 (13)	C12—C11—C10	120.59 (13)
N1—C5—C6	116.09 (12)	C13—C12—C11	118.48 (14)
C4—C5—C6	120.91 (12)	C14—C13—C12	119.06 (14)
N2—C6—C7	123.83 (13)	C15—C14—C13	118.38 (14)
N2—C6—C5	115.77 (12)	N3—C15—C14	124.12 (14)
C7—C6—C5	120.39 (12)	O—C16—C17	109.06 (11)
C8—C7—C6	118.09 (13)	C16—C17—C18	109.71 (12)
O—C8—C7	124.28 (12)	C18ⁱ—C18—C17	112.98 (15)
O—C8—C9	116.87 (12)	C1—N1—C5	117.52 (12)
C7—C8—C9	118.86 (13)	C6—N2—C10	117.06 (11)
C10—C9—C8	118.87 (13)	C15—N3—C11	117.05 (12)
N2—C10—C9	123.26 (13)	C8—O—C16	116.58 (11)

N1—C1—C2—C3	0.8 (2)	N3—C11—C12—C13	−1.0 (2)
C1—C2—C3—C4	0.4 (2)	C10—C11—C12—C13	178.92 (12)
C2—C3—C4—C5	−0.9 (2)	C11—C12—C13—C14	0.7 (2)
C3—C4—C5—N1	0.3 (2)	C12—C13—C14—C15	0.7 (2)
C3—C4—C5—C6	−178.31 (13)	C13—C14—C15—N3	−2.1 (2)
N1—C5—C6—N2	155.72 (12)	O—C16—C17—C18	−179.36 (11)
C4—C5—C6—N2	−25.62 (19)	C16—C17—C18—C18ⁱ	−176.75 (15)
N1—C5—C6—C7	−25.77 (19)	C2—C1—N1—C5	−1.4 (2)
C4—C5—C6—C7	152.89 (13)	C4—C5—N1—C1	0.9 (2)
N2—C6—C7—C8	1.3 (2)	C6—C5—N1—C1	179.51 (12)
C5—C6—C7—C8	−177.08 (12)	C7—C6—N2—C10	−0.4 (2)
C6—C7—C8—O	179.13 (13)	C5—C6—N2—C10	178.08 (12)
C6—C7—C8—C9	−0.5 (2)	C9—C10—N2—C6	−1.4 (2)
O—C8—C9—C10	179.26 (12)	C11—C10—N2—C6	179.51 (12)
C7—C8—C9—C10	−1.1 (2)	C14—C15—N3—C11	1.8 (2)
C8—C9—C10—N2	2.1 (2)	C12—C11—N3—C15	−0.2 (2)
C8—C9—C10—C11	−178.83 (12)	C10—C11—N3—C15	179.86 (12)
N2—C10—C11—N3	−175.94 (12)	C7—C8—O—C16	3.91 (19)
C9—C10—C11—N3	4.92 (19)	C9—C8—O—C16	−176.42 (12)
N2—C10—C11—C12	4.17 (19)	C17—C16—O—C8	−177.42 (11)
C9—C10—C11—C12	−174.98 (14)

Symmetry code: (i) −x, −y−1, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C15—H15···Oⁱⁱ	0.95	2.65	3.575 (2)	164
C1—H1···N3ⁱⁱⁱ	0.95	2.71	3.654 (2)	174
C4—H4···N1^iv	0.95	2.65	3.402 (2)	136
C2—H2···Oⁱⁱⁱ	0.95	2.69	3.627 (2)	168

Symmetry codes: (ii) −x, y+1/2, −z+3/2; (iii) −x+1/2, −y, z−1/2; (iv) −x+1/2, y+1/2, z.

Experimental details

Crystal data
Chemical formula	C₃₆H₃₂N₆O₂
M_r	580.7
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	100
a, b, c (Å)	15.139 (5), 11.428 (5), 16.760 (5)
V (Å³)	2899.6 (18)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.40 × 0.20 × 0.20

Data collection
Diffractometer	Oxford Diffraction Xcalibur 2 CCD
Absorption correction	Multi-scan (Blessing, 1995)
T_min, T_max	0.967, 0.983
No. of measured, independent and observed [I > 2σ(I)] reflections	20354, 2859, 2098
R_int	0.064
(sin θ/λ)_max (Å⁻¹)	0.618

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.038, 0.100, 0.94
No. of reflections	2859
No. of parameters	199
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.17, −0.26

Computer programs: CrysAlis CCD (Oxford Diffraction, 2008), CrysAlis RED (Oxford Diffraction, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1999), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C15—H15···Oⁱ	0.950	2.652	3.575 (2)	164
C1—H1···N3ⁱⁱ	0.950	2.708	3.654 (2)	174
C4—H4···N1ⁱⁱⁱ	0.949	2.652	3.402 (2)	136
C2—H2···Oⁱⁱ	0.950	2.694	3.627 (2)	168

Symmetry codes: (i) −x, y+1/2, −z+3/2; (ii) −x+1/2, −y, z−1/2; (iii) −x+1/2, y+1/2, z.

Acknowledgements

We wish to thank the Univeristy of Kwazulu-Natal for supporting this research by providing both funding and facilities.

References

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