3,4-Di­methyl­phenyl quinoline-2-carboxyl­ate

Fazal, E.; Kaur, M.; Sudha, B.S.; Nagarajan, S.; Jasinski, J.P.

doi:10.1107/S1600536813032157

organic compounds

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ISSN: 2056-9890

Volume 69| Part 12| December 2013| Pages o1853-o1854

doi:10.1107/S1600536813032157

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3,4-Dimethylphenyl quinoline-2-carboxylate

E. Fazal,^a Manpreet Kaur,^b B. S. Sudha,^a S. Nagarajan ^c and Jerry P. Jasinski ^d ^*

^aDepartment of Chemistry, Yuvaraja's College, Mysore 570 005, India, ^bDepartment of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570 006, India, ^cP.P.S.F.T. Department, Central Food Technplogy Research institute, Mysore 570 005, India, and ^dDepartment of Chemistry, Keene State College, 229 Main Street, Keene, NH 03435-2001, USA
^*Correspondence e-mail: jjasinski@keene.edu

(Received 24 November 2013; accepted 25 November 2013; online 30 November 2013)

In the title compound, C₁₈H₁₅NO₂, the dihedral angle between the mean planes of the quinoline ring system and the phenyl ring is 48.1 (5)°. The mean plane of the carboxylate group is twisted from the mean planes of the latter by 19.8 (8) and 64.9 (5)°, respectively. The crystal packing features weak C—H⋯O interactions, which form chains along [010].

CCDC reference: 973659

Related literature

For heterocycles in natural products, see: Morimoto et al. (1991 ); Michael (1997 ). For heterocycles in fragrances and dyes, see: Padwa et al. (1999 ). For heterocycles in biologically active compounds, see: Markees et al. (1970 ); Campbell et al. (1988 ). For the use of quinoline alkaloids as drugs for the treatment of malaria, see: Robert & Meunier (1998 ). For quinoline as a privileged scaffold in cancer drug discovery, see: Solomon & Lee (2011 ). For related structures, see: Fazal et al. (2012 ); Butcher et al. (2007 ); Jing & Qin (2008 ); Jasinski et al. (2010 ). For standard bond lengths, see: Allen et al. (1987 ).

Experimental

Crystal data

C₁₈H₁₅NO₂
M_r = 277.32
Monoclinic, P 2₁ /c
a = 6.19172 (17) Å
b = 15.4196 (4) Å
c = 14.6585 (4) Å
β = 90.761 (3)°
V = 1399.38 (7) Å³
Z = 4
Cu Kα radiation
μ = 0.69 mm⁻¹
T = 173 K
0.44 × 0.22 × 0.16 mm

Data collection

Agilent Xcalibur (Eos, Gemini) diffractometer
Absorption correction: multi-scan (CrysAlis PRO and CrysAlis RED; Agilent, 2012 ) T_min = 0.921, T_max = 1.000
8355 measured reflections
2740 independent reflections
2387 reflections with I > 2σ(I)
R_int = 0.042

Refinement

R[F² > 2σ(F²)] = 0.042
wR(F²) = 0.121
S = 1.05
2740 reflections
193 parameters
H-atom parameters constrained
Δρ_max = 0.28 e Å⁻³
Δρ_min = −0.24 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C8—H8⋯O1ⁱ	0.93	2.48	3.2735 (16)	144
Symmetry code: (i) $[-x, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Data collection: CrysAlis PRO (Agilent, 2012); cell refinement: CrysAlis PRO; data reduction: CrysAlis RED (Agilent, 2012); program(s) used to solve structure: SUPERFLIP (Palatinus & Chapuis, 2007 ); program(s) used to refine structure: SHELXL2012 (Sheldrick, 2008 ); molecular graphics: OLEX2 (Dolomanov et al., 2009 ); software used to prepare material for publication: OLEX2.

Supporting information

CCDC reference: 973659

Crystal structure: contains datablock I. DOI: 10.1107/S1600536813032157/qm2101sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813032157/qm2101Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536813032157/qm2101Isup3.cml

checkCIF report

Comment top

Quinoline-2 carboxylic acid derivatives are a class of important materials as anti-tuberculosis agents, as fluorescent reagents, hydrophobic field-detection reagents, visualisation reagents, fluorescent labelled peptide probes and as antihyperglycemics. Quinoline derivatives represent a major class of heterocycles and are found in natural products(Morimoto et al., 1991; Michael, 1997), numerous commercial products, including fragrances, dyes(Padwa et al., 1999)and biologically active compounds (Markees et al., 1970; Campbell et al., 1988). Quinoline alkaloids such as quinine,chloroquin, mefloquine and amodiaquine are used as efficient drugs for the treatment of malaria (Robert & Meunier,1998). Quinoline has been used as a privileged scaffold in cancer drug discovery (Solomon & Lee, 2011). The crystal structures of 4-methylphenyl quinoline-2-carboxylate (Fazal et al.,2012), 1-(quinolin-2-yl)ethanone(Butcher et al., 2007) and methyl quinoline-2-carboxylate (Jing & Qin, 2008) and the synthesis, crystal structures and theoretical studies of four Schiff bases derived from 4-hydrazinyl-8-(trifluoromethyl) quinoline (Jasinski et al., 2010) have been reported. In view of the importance of quinolines, this paper reports the crystal structure of the title compound, (I), C₁₈H₁₅NO₂.

In the title compound, C₁₈H₁₅NO₂, the dihedral angle between the mean planes of the quinoline ring and the phenyl ring is 48.1 (5)° (Fig. 1). The mean plane of the carboxylate group is twisted from the mean planes of the quinoline ring and phenyl ring by 19.8 (8)° and 64.9 (5)°, respectively. The crystal packing is influenced by weak C8—H8···O1 intermolecular interactions making chains along [0 1 0](Fig. 2). No classical hydrogen bonds were observed.

Related literature top

For heterocycles in natural products, see: Morimoto et al. (1991); Michael (1997). For heterocycles in fragrances and dyes, see: Padwa et al. (1999). For heterocycles in biologically active compounds, see: Markees et al. (1970); Campbell et al. (1988). For the use of quinoline alkaloids as efficient drugs for the treatment of malaria, see: Robert & Meunier (1998). For quinoline as a privileged scaffold in cancer drug discovery, see: Solomon & Lee (2011). For related structures, see: Fazal et al. (2012); Butcher et al. (2007); Jing & Qin (2008); Jasinski et al. (2010). For standard bond lengths, see: Allen et al. (1987).

Experimental top

The title compound was prepared by the following procedure: To a mixture of 1.73 g (10 mmole) of quinaldic acid and 1.56 g (10 mmole) of 3,4-dimethylphenol in a round-bottomed flask fitted with a reflex condenser with a drying tube is added 0.15 g (10 mmole) of phosphorous oxychloride. The mixture is heated with occasional swirling, and temperature is maintained at 348-353 K. At the end of eight hours the reaction mixture is poured in to a solution of 2 g of sodium bicarbonate in 25 mL of water. The precipitated ester is collected on a filter and washed with water. The yield of crude, air dried 3,4-dimethyl phenyl quinoline-2-carboxylate is 1.47 to 1.90 g (50-65%). X-ray quality crystal was obtained by recrystallization from absolute ethanol.(M.P.:397 K)

Computing details top

Data collection: CrysAlis PRO (Agilent, 2012); cell refinement: CrysAlis PRO (Agilent, 2012); data reduction: CrysAlis RED (Agilent, 2012); program(s) used to solve structure: SUPERFLIP (Palatinus & Chapuis, 2007); program(s) used to refine structure: SHELXL2012 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Figures top

	Fig. 1. ORTEP drawing of (I) (C₁₈H₁₅NO₂) showing the labeling scheme with 50% probability displacement ellipsoids.
	Fig. 2. Molecular packing for (I) viewed along the a axis. Dashed lines indicate weak C8—H8···O1 intermolecular interactions making chains along [0 1 0] and influence the crystal packing. The remaining H atoms have been removed for clarity.

3,4-Dimethylphenyl quinoline-2-carboxylate top

Crystal data top

C₁₈H₁₅NO₂	F(000) = 608
M_r = 277.32	D_x = 1.316 Mg m⁻³
Monoclinic, P2₁/c	Cu Kα radiation, λ = 1.54184 Å
a = 6.19172 (17) Å	Cell parameters from 6294 reflections
b = 15.4196 (4) Å	θ = 4.7–72.3°
c = 14.6585 (4) Å	µ = 0.69 mm⁻¹
β = 90.761 (3)°	T = 173 K
V = 1399.38 (7) Å³	Irregular, clear red
Z = 4	0.44 × 0.22 × 0.16 mm

Data collection top

Agilent Xcalibur (Eos, Gemini) diffractometer	2740 independent reflections
Radiation source: Enhance (Cu) X-ray Source	2387 reflections with I > 2σ(I)
Detector resolution: 16.0416 pixels mm^-1	R_int = 0.042
ω scans	θ_max = 72.3°, θ_min = 4.2°
Absorption correction: multi-scan (CrysAlis PRO and CrysAlis RED; Agilent, 2012)	h = −7→6
T_min = 0.921, T_max = 1.000	k = −18→19
8355 measured reflections	l = −14→18

Refinement top

Refinement on F²	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.042	w = 1/[σ²(F_o²) + (0.0716P)² + 0.1805P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.121	(Δ/σ)_max < 0.001
S = 1.05	Δρ_max = 0.28 e Å⁻³
2740 reflections	Δρ_min = −0.24 e Å⁻³
193 parameters	Extinction correction: SHELXL2012 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.0048 (6)
Primary atom site location: structure-invariant direct methods

Crystal data top

C₁₈H₁₅NO₂	V = 1399.38 (7) Å³
M_r = 277.32	Z = 4
Monoclinic, P2₁/c	Cu Kα radiation
a = 6.19172 (17) Å	µ = 0.69 mm⁻¹
b = 15.4196 (4) Å	T = 173 K
c = 14.6585 (4) Å	0.44 × 0.22 × 0.16 mm
β = 90.761 (3)°

Data collection top

Agilent Xcalibur (Eos, Gemini) diffractometer	2740 independent reflections
Absorption correction: multi-scan (CrysAlis PRO and CrysAlis RED; Agilent, 2012)	2387 reflections with I > 2σ(I)
T_min = 0.921, T_max = 1.000	R_int = 0.042
8355 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.042	0 restraints
wR(F²) = 0.121	H-atom parameters constrained
S = 1.05	Δρ_max = 0.28 e Å⁻³
2740 reflections	Δρ_min = −0.24 e Å⁻³
193 parameters

Special details top

Experimental. ¹H NMR(500 MHz,DMSO) δ 8.66 (1H,d, J= 8.5Hz), 8.26(1H,d, J= 8.5Hz),8.24(1H,d, J= 8.5 Hz), 8.15(1H,d, J= 8.03 Hz),7.93(1H,dt, J1= 8.2Hz, J2=6.46, J3=1.08Hz), 7.8(1H,t, J= 7.5Hz), 7.25(1H,d, J= 8.2Hz), 7.14(1H,d, J= 2.15Hz), 7.06(1H,dd, J1= 8.03Hz,J2=2.35),2.28(3H,s),2.25(3H,s).

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.03672 (17)	0.48206 (6)	0.20779 (8)	0.0457 (3)
O2	0.26816 (14)	0.53658 (5)	0.10569 (6)	0.0302 (2)
N1	0.23607 (16)	0.32280 (7)	0.18546 (7)	0.0247 (2)
C1	0.19203 (19)	0.47407 (8)	0.16176 (8)	0.0269 (3)
C2	0.33036 (19)	0.39405 (8)	0.15562 (8)	0.0247 (3)
C3	0.54041 (19)	0.39753 (8)	0.11950 (8)	0.0286 (3)
H3	0.5996	0.4500	0.1010	0.034*
C4	0.65466 (19)	0.32226 (8)	0.11227 (8)	0.0287 (3)
H4	0.7945	0.3229	0.0899	0.034*
C5	0.55877 (19)	0.24325 (8)	0.13906 (8)	0.0258 (3)
C6	0.6605 (2)	0.16151 (9)	0.12935 (9)	0.0315 (3)
H6	0.7976	0.1583	0.1044	0.038*
C7	0.5586 (2)	0.08740 (9)	0.15634 (9)	0.0358 (3)
H7	0.6258	0.0340	0.1487	0.043*
C8	0.3518 (2)	0.09127 (8)	0.19569 (9)	0.0339 (3)
H8	0.2852	0.0404	0.2146	0.041*
C9	0.2485 (2)	0.16894 (8)	0.20625 (9)	0.0284 (3)
H9	0.1129	0.1707	0.2328	0.034*
C10	0.34768 (19)	0.24685 (8)	0.17682 (8)	0.0240 (3)
C12	0.26169 (19)	0.69008 (8)	0.12548 (8)	0.0254 (3)
H12	0.3995	0.6863	0.1512	0.031*
C13	0.1647 (2)	0.77085 (8)	0.11323 (8)	0.0263 (3)
C14	−0.0431 (2)	0.77561 (8)	0.07407 (8)	0.0280 (3)
C15	−0.1486 (2)	0.69903 (9)	0.04954 (8)	0.0296 (3)
H15	−0.2870	0.7020	0.0243	0.036*
C16	−0.0521 (2)	0.61829 (8)	0.06192 (8)	0.0287 (3)
H16	−0.1240	0.5676	0.0453	0.034*
C17	0.1535 (2)	0.61561 (8)	0.09951 (8)	0.0257 (3)
C18	0.2807 (2)	0.85201 (9)	0.14296 (10)	0.0362 (3)
H18A	0.4197	0.8370	0.1681	0.054*
H18B	0.1974	0.8813	0.1884	0.054*
H18C	0.2989	0.8895	0.0913	0.054*
C19	−0.1517 (2)	0.86210 (9)	0.05940 (10)	0.0402 (3)
H19A	−0.1732	0.8897	0.1173	0.060*
H19B	−0.2888	0.8535	0.0294	0.060*
H19C	−0.0622	0.8981	0.0222	0.060*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0474 (6)	0.0355 (5)	0.0550 (7)	0.0099 (4)	0.0268 (5)	0.0120 (4)
O2	0.0339 (5)	0.0233 (5)	0.0335 (5)	0.0028 (3)	0.0083 (4)	0.0041 (3)
N1	0.0242 (5)	0.0260 (5)	0.0240 (5)	−0.0007 (4)	0.0019 (4)	0.0017 (4)
C1	0.0291 (6)	0.0257 (6)	0.0258 (6)	−0.0021 (5)	0.0025 (5)	0.0001 (5)
C2	0.0269 (6)	0.0256 (6)	0.0215 (6)	−0.0014 (4)	0.0000 (4)	0.0012 (4)
C3	0.0282 (6)	0.0287 (6)	0.0290 (6)	−0.0052 (5)	0.0021 (5)	0.0046 (5)
C4	0.0223 (6)	0.0356 (7)	0.0282 (6)	−0.0012 (5)	0.0040 (5)	0.0033 (5)
C5	0.0259 (6)	0.0295 (6)	0.0221 (6)	0.0010 (5)	−0.0008 (4)	0.0010 (4)
C6	0.0290 (6)	0.0362 (7)	0.0293 (6)	0.0059 (5)	0.0024 (5)	0.0002 (5)
C7	0.0438 (8)	0.0273 (7)	0.0362 (7)	0.0085 (5)	−0.0010 (6)	−0.0010 (5)
C8	0.0420 (7)	0.0246 (6)	0.0352 (7)	−0.0038 (5)	−0.0012 (6)	0.0027 (5)
C9	0.0276 (6)	0.0290 (6)	0.0288 (6)	−0.0035 (5)	0.0019 (5)	0.0021 (5)
C10	0.0250 (6)	0.0256 (6)	0.0214 (6)	−0.0004 (4)	−0.0007 (4)	0.0010 (4)
C12	0.0253 (6)	0.0283 (6)	0.0228 (6)	0.0005 (5)	0.0009 (5)	0.0003 (4)
C13	0.0314 (6)	0.0255 (6)	0.0221 (6)	−0.0004 (5)	0.0041 (5)	−0.0012 (4)
C14	0.0306 (6)	0.0304 (6)	0.0230 (6)	0.0058 (5)	0.0047 (5)	0.0006 (5)
C15	0.0249 (6)	0.0390 (7)	0.0250 (6)	0.0009 (5)	0.0004 (5)	0.0012 (5)
C16	0.0316 (6)	0.0290 (6)	0.0255 (6)	−0.0064 (5)	0.0026 (5)	−0.0012 (5)
C17	0.0304 (6)	0.0237 (6)	0.0231 (6)	0.0022 (4)	0.0058 (5)	0.0016 (4)
C18	0.0433 (8)	0.0278 (7)	0.0374 (7)	−0.0023 (5)	−0.0016 (6)	−0.0038 (5)
C19	0.0420 (8)	0.0372 (8)	0.0415 (8)	0.0129 (6)	0.0024 (6)	0.0027 (6)

Geometric parameters (Å, º) top

O1—C1	1.1885 (15)	C9—H9	0.9300
O2—C1	1.3554 (14)	C9—C10	1.4191 (16)
O2—C17	1.4127 (14)	C12—H12	0.9300
N1—C2	1.3214 (15)	C12—C13	1.3933 (17)
N1—C10	1.3665 (15)	C12—C17	1.3806 (17)
C1—C2	1.5053 (16)	C13—C14	1.4039 (18)
C2—C3	1.4118 (17)	C13—C18	1.5045 (17)
C3—H3	0.9300	C14—C15	1.3943 (18)
C3—C4	1.3640 (17)	C14—C19	1.5077 (17)
C4—H4	0.9300	C15—H15	0.9300
C4—C5	1.4132 (17)	C15—C16	1.3918 (18)
C5—C6	1.4170 (17)	C16—H16	0.9300
C5—C10	1.4272 (17)	C16—C17	1.3809 (18)
C6—H6	0.9300	C18—H18A	0.9600
C6—C7	1.3666 (19)	C18—H18B	0.9600
C7—H7	0.9300	C18—H18C	0.9600
C7—C8	1.4122 (19)	C19—H19A	0.9600
C8—H8	0.9300	C19—H19B	0.9600
C8—C9	1.3676 (18)	C19—H19C	0.9600

C1—O2—C17	118.28 (9)	C9—C10—C5	119.16 (11)
C2—N1—C10	117.11 (10)	C13—C12—H12	120.0
O1—C1—O2	124.13 (11)	C17—C12—H12	120.0
O1—C1—C2	125.75 (11)	C17—C12—C13	120.08 (11)
O2—C1—C2	110.12 (10)	C12—C13—C14	119.38 (11)
N1—C2—C1	114.05 (10)	C12—C13—C18	120.20 (11)
N1—C2—C3	124.68 (11)	C14—C13—C18	120.42 (11)
C3—C2—C1	121.26 (10)	C13—C14—C19	120.60 (12)
C2—C3—H3	120.7	C15—C14—C13	119.01 (11)
C4—C3—C2	118.56 (11)	C15—C14—C19	120.39 (12)
C4—C3—H3	120.7	C14—C15—H15	119.2
C3—C4—H4	120.3	C16—C15—C14	121.67 (11)
C3—C4—C5	119.46 (11)	C16—C15—H15	119.2
C5—C4—H4	120.3	C15—C16—H16	121.0
C4—C5—C6	123.37 (11)	C17—C16—C15	118.08 (11)
C4—C5—C10	117.68 (11)	C17—C16—H16	121.0
C6—C5—C10	118.95 (11)	C12—C17—O2	117.27 (11)
C5—C6—H6	119.8	C12—C17—C16	121.77 (11)
C7—C6—C5	120.48 (12)	C16—C17—O2	120.75 (11)
C7—C6—H6	119.8	C13—C18—H18A	109.5
C6—C7—H7	119.7	C13—C18—H18B	109.5
C6—C7—C8	120.50 (12)	C13—C18—H18C	109.5
C8—C7—H7	119.7	H18A—C18—H18B	109.5
C7—C8—H8	119.6	H18A—C18—H18C	109.5
C9—C8—C7	120.74 (12)	H18B—C18—H18C	109.5
C9—C8—H8	119.6	C14—C19—H19A	109.5
C8—C9—H9	119.9	C14—C19—H19B	109.5
C8—C9—C10	120.13 (11)	C14—C19—H19C	109.5
C10—C9—H9	119.9	H19A—C19—H19B	109.5
N1—C10—C5	122.42 (10)	H19A—C19—H19C	109.5
N1—C10—C9	118.42 (11)	H19B—C19—H19C	109.5

O1—C1—C2—N1	18.18 (18)	C8—C9—C10—N1	177.64 (11)
O1—C1—C2—C3	−162.66 (13)	C8—C9—C10—C5	−2.07 (18)
O2—C1—C2—N1	−160.96 (10)	C10—N1—C2—C1	176.20 (10)
O2—C1—C2—C3	18.20 (16)	C10—N1—C2—C3	−2.92 (18)
N1—C2—C3—C4	1.69 (19)	C10—C5—C6—C7	−0.47 (19)
C1—O2—C17—C12	118.93 (12)	C12—C13—C14—C15	0.89 (18)
C1—O2—C17—C16	−66.23 (14)	C12—C13—C14—C19	−179.61 (11)
C1—C2—C3—C4	−177.37 (11)	C13—C12—C17—O2	174.15 (10)
C2—N1—C10—C5	1.18 (17)	C13—C12—C17—C16	−0.63 (18)
C2—N1—C10—C9	−178.52 (11)	C13—C14—C15—C16	−0.78 (18)
C2—C3—C4—C5	1.36 (18)	C14—C15—C16—C17	−0.04 (18)
C3—C4—C5—C6	176.44 (12)	C15—C16—C17—O2	−173.85 (10)
C3—C4—C5—C10	−2.87 (18)	C15—C16—C17—C12	0.75 (18)
C4—C5—C6—C7	−179.76 (12)	C17—O2—C1—O1	−1.63 (18)
C4—C5—C10—N1	1.64 (18)	C17—O2—C1—C2	177.53 (10)
C4—C5—C10—C9	−178.66 (11)	C17—C12—C13—C14	−0.21 (18)
C5—C6—C7—C8	−1.0 (2)	C17—C12—C13—C18	178.94 (11)
C6—C5—C10—N1	−177.69 (11)	C18—C13—C14—C15	−178.26 (11)
C6—C5—C10—C9	2.00 (18)	C18—C13—C14—C19	1.24 (18)
C6—C7—C8—C9	1.0 (2)	C19—C14—C15—C16	179.73 (11)
C7—C8—C9—C10	0.58 (19)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8···O1ⁱ	0.93	2.48	3.2735 (16)	144

Symmetry code: (i) −x, y−1/2, −z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8···O1ⁱ	0.93	2.48	3.2735 (16)	143.7

Symmetry code: (i) −x, y−1/2, −z+1/2.

Acknowledgements

EF thanks the CFTRI, Mysore and Yuvaraja's college, UOM for providing research facilities. EF is grateful to Mr J. R. Manjunatha, PPSFT, CFTRI for the NMR spectra. JPJ acknowledges the NSF–MRI program (grant No. CHE-1039027) for funds to purchase the X-ray diffractometer.

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