8-(Naphthalen-1-yl)quinoline

Kanu, G.; Lalancette, R.A.; Vitale, D.E.

doi:10.1107/S1600536811034052

organic compounds

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ISSN: 2056-9890

Volume 67| Part 9| September 2011| Page o2522

doi:10.1107/S1600536811034052

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8-(Naphthalen-1-yl)quinoline

Godwin Kanu,^a Roger A. Lalancette ^b and Dale E. Vitale ^c ^*

^aDepartment of Chemistry and Biochemistry, UCLA, 607 Charles E. Young Drive East, Box 951569, Los Angeles, CA 90095, USA, ^bDepartment of Chemistry, Rutgers University-Newark, 73 Warren Street, Newark, NJ 07102-1811, USA, and ^cDepartment of Chemistry, Kean University, Union, NJ 07083, USA
^*Correspondence e-mail: dvitale@kean.edu

(Received 28 July 2011; accepted 19 August 2011; online 31 August 2011)

In the title molecule, C₁₉H₁₃N, the angle between the mean planes of the naphthalene and quinoline ring systems is 68.59 (2)°. The compound is of interest with respect to its potential for spontaneous resolution. In the crystal structure, the R and S isomers are arranged in alternating homochiral layers. The molecules of a given layer are oriented with their major axes (i.e. the axis perpendicular to the interannular bond) in the same direction and their naphthalene and quinoline ring systems are arranged parallel. Like the configurations, this orientation alternates in adjacent layers.

Related literature

For spontanteous-resolution experiments, see: Asakura & Plasson (2006 ); Kondipudi et al. (1999 ); Kranz et al. (1993 ); Sainz-Diaz et al. (2005 ); Wilson & Pincock (1974 ). For related structures, see: Kerr & Robertson (1969 ); Kuroda & Manson (1981 ). For details of the synthesis, see: Huff et al. (1998 ).

Experimental

Crystal data

C₁₉H₁₃N
M_r = 255.30
Triclinic, $[P \overline 1]$
a = 6.1778 (1) Å
b = 10.0392 (2) Å
c = 10.8828 (2) Å
α = 104.537 (1)°
β = 106.435 (1)°
γ = 90.002 (1)°
V = 624.80 (2) Å³
Z = 2
Cu Kα radiation
μ = 0.61 mm⁻¹
T = 100 K
0.37 × 0.20 × 0.10 mm

Data collection

Bruker SMART CCD APEXII diffractometer
Absorption correction: numerical (SADABS; Sheldrick, 2008 ) T_min = 0.806, T_max = 0.942
5783 measured reflections
2058 independent reflections
1678 reflections with I > 2σ(I)
R_int = 0.011

Refinement

R[F² > 2σ(F²)] = 0.044
wR(F²) = 0.131
S = 1.06
2058 reflections
181 parameters
H-atom parameters constrained
Δρ_max = 0.38 e Å⁻³
Δρ_min = −0.34 e Å⁻³

Data collection: APEX2 (Bruker, 2006 ); cell refinement: APEX2; data reduction: SAINT (Bruker, 2005 ); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL; molecular graphics: Mercury (Macrae et al., 2008 ); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811034052/lh5298sup1.cif

Supporting information file. DOI: 10.1107/S1600536811034052/lh5298Isup2.mol

Structure factors: contains datablock I. DOI: 10.1107/S1600536811034052/lh5298Isup3.hkl

Supporting information file. DOI: 10.1107/S1600536811034052/lh5298Isup4.cml

checkCIF report

Comment top

The structural similarities between the title compound (81QNNP) and 1,1'-binaphthalenyl (11BNP) suggest that, like the hydrocarbon, 81QNNP might exhibit spontaneous resolution. The characteristics that afford spontaneous resolution of the racemic compound of 11BNP are its dimorphism and moderate barrier to rotation about the C1—C1' interannular bond (Kranz et al., 1993). The barrier is large enough to prevent racemization of resolved forms below about 351 K, but small enough to afford rapid interconversion of the enantiomers in the melt. The dimorphs consist of an optically inactive racemic compound (Kerr & Robertson, 1969) that is the more stable form at temperatures below 351 K and a conglomerate of single crystals of the R and S isomers (Kuroda & Manson, 1981) that is the more stable above this temperature. Accordingly, heating of the racemic compound above the melting point of the conglomerate (431 K) followed by supercooling to 423 K can produce an optically active solid (Kondipudi et al., 1999).

The molecular structure of the title compound is shown in Fig. 1. The title compound closely resembles 1,1-binaphthalenyl in molecular structure, crystal structure, and thermal behavior (Wilson & Pincock, 1974). On the molecular level, the two compounds differ only in the substitution of a nitrogen in 81QNNP for the C8 carbon in 11BNP. Likewise, the room temperature solid of 81QNNP is an optically inactive racemic compound with the components of an enantiotopic pair of molecules in the unit cell. Moreover, while spontaneous development of optical activity has not been demonstrated in the title compound, preliminary DSC results suggest that it is polymorphic. This means that, in addition to the racemic compound described herein, 81QNNP may also exist as a conglomerate. If so, it has the potential for spontaneous resolution via a mechanism similar to that of 11BNP (Asakura & Plasson, 2006; Sainz-Diaz et al., 2005). In the crystal, the R and S isomers are arranged in alternating homochiral layers. The molecules of a given layer are oriented with their major axes in the same direction and their naphthalene and quinoline ring systems are arranged parallel. Like the configurations this orientation alternates in adjacent layers (Fig. 2).

Related literature top

For spontanteous-resolution experiments, see: Asakura & Plasson (2006); Kondipudi et al. (1999); Kranz et al. (1993); Sainz-Diaz et al. (2005); Wilson & Pincock (1974). For related structures, see: Kerr & Robertson (1969); Kuroda & Manson (1981). For details of the synthesis, see: Huff et al. (1998).

Experimental top

The synthesis was carried out according to a literature procedure (Huff et al., 1998). 8-(Naphthalen-1-yl)quinoline was synthesized in 58% yield from 8-bromoquinoline (Frontier Chemical) and 1-naphthalenylboronic acid (Sigma–Aldrich) using a modification of the Suzuki coupling reaction (Huff et al., 1998) and crystallized from 1-propanol; m.p. 436.0–437.5 K, ¹³C NMR (CDCl₃): DEPT-CH δ 121.3, 125.6, 125.9, 126.0, 126.4, 127.0, 128.1, 128.2, 128.3, 128.6, 131.9, 136.4, 150.9 p.p.m. IR (KBr ν cm^-1): 3041 (CH_ar) 1592 and 1491 (C═C and C═N), 1379, 1310, 1204, 1064, 1015, 944, 828, 797, 782, 772, 677, 617, 517.

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: APEX2 (Bruker, 2006); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the S enantiomer of (I) with atom numbering scheme. Displacement ellipsoids are drawn at 50% probability level.
	Fig. 2. Alternating layers of R and S isomers viewed along c axis; R, S, R, S from top of figure.

8-(Naphthalen-1-yl)quinoline top

Crystal data top

C₁₉H₁₃N	Z = 2
M_r = 255.30	F(000) = 268
Triclinic, P1	D_x = 1.357 Mg m⁻³
Hall symbol: -P 1	Melting point = 436.0–437.5 K
a = 6.1778 (1) Å	Cu Kα radiation, λ = 1.54178 Å
b = 10.0392 (2) Å	Cell parameters from 3661 reflections
c = 10.8828 (2) Å	θ = 4.4–66.7°
α = 104.537 (1)°	µ = 0.61 mm⁻¹
β = 106.435 (1)°	T = 100 K
γ = 90.002 (1)°	Plate, colourless
V = 624.80 (2) Å³	0.37 × 0.20 × 0.10 mm

Data collection top

Bruker SMART CCD APEXII diffractometer	2058 independent reflections
Radiation source: fine-focus sealed tube	1678 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.011
ϕ and ω scans	θ_max = 67.5°, θ_min = 4.4°
Absorption correction: numerical (SADABS; Sheldrick, 2008)	h = −7→7
T_min = 0.806, T_max = 0.942	k = −11→11
5783 measured reflections	l = −12→12

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)] = 0.044	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.131	H-atom parameters constrained
S = 1.06	w = 1/[σ²(F_o²) + (0.0654P)² + 0.348P] where P = (F_o² + 2F_c²)/3
2058 reflections	(Δ/σ)_max < 0.001
181 parameters	Δρ_max = 0.38 e Å⁻³
0 restraints	Δρ_min = −0.34 e Å⁻³

Crystal data top

C₁₉H₁₃N	γ = 90.002 (1)°
M_r = 255.30	V = 624.80 (2) Å³
Triclinic, P1	Z = 2
a = 6.1778 (1) Å	Cu Kα radiation
b = 10.0392 (2) Å	µ = 0.61 mm⁻¹
c = 10.8828 (2) Å	T = 100 K
α = 104.537 (1)°	0.37 × 0.20 × 0.10 mm
β = 106.435 (1)°

Data collection top

Bruker SMART CCD APEXII diffractometer	2058 independent reflections
Absorption correction: numerical (SADABS; Sheldrick, 2008)	1678 reflections with I > 2σ(I)
T_min = 0.806, T_max = 0.942	R_int = 0.011
5783 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.044	0 restraints
wR(F²) = 0.131	H-atom parameters constrained
S = 1.06	Δρ_max = 0.38 e Å⁻³
2058 reflections	Δρ_min = −0.34 e Å⁻³
181 parameters

Special details top

Experimental. crystal mounted on a Cryoloop using Paratone-N

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'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
N1	0.9761 (3)	0.89896 (16)	1.10848 (15)	0.0304 (4)
C2	1.1692 (3)	0.96964 (18)	1.19213 (17)	0.0269 (4)
H2	1.2610	1.0176	1.1579	0.032*
C3	1.2400 (3)	0.97528 (18)	1.32817 (17)	0.0268 (4)
H3	1.3785	1.0249	1.3839	0.032*
C4	1.1084 (3)	0.90897 (17)	1.37947 (16)	0.0233 (4)
H4	1.1549	0.9126	1.4713	0.028*
C4A	0.9019 (3)	0.83446 (16)	1.29589 (15)	0.0207 (4)
C5	0.7566 (3)	0.76657 (17)	1.34510 (16)	0.0230 (4)
H5	0.7968	0.7702	1.4369	0.028*
C6	0.5598 (3)	0.69612 (17)	1.26156 (16)	0.0243 (4)
H6	0.4636	0.6510	1.2954	0.029*
C7	0.4982 (3)	0.68992 (17)	1.12520 (16)	0.0236 (4)
H7	0.3602	0.6406	1.0684	0.028*
C8	0.6333 (3)	0.75369 (17)	1.07236 (16)	0.0211 (4)
C8A	0.8399 (3)	0.82928 (16)	1.15855 (15)	0.0197 (4)
C1'	0.5605 (3)	0.74639 (17)	0.92755 (16)	0.0210 (4)
C2'	0.3732 (3)	0.81036 (17)	0.87514 (16)	0.0234 (4)
H2'	0.2924	0.8601	0.9321	0.028*
C3'	0.2981 (3)	0.80380 (17)	0.73857 (16)	0.0244 (4)
H3'	0.1677	0.8487	0.7048	0.029*
C4'	0.4114 (3)	0.73338 (17)	0.65465 (16)	0.0229 (4)
H4'	0.3598	0.7297	0.5628	0.027*
C4A'	0.6059 (3)	0.66569 (16)	0.70394 (15)	0.0207 (4)
C5'	0.7289 (3)	0.59114 (17)	0.62054 (16)	0.0234 (4)
H5'	0.6837	0.5877	0.5287	0.028*
C6'	0.9118 (3)	0.52436 (18)	0.67111 (17)	0.0263 (4)
H6'	0.9937	0.4743	0.6150	0.032*
C7'	0.9774 (3)	0.53047 (18)	0.80697 (17)	0.0274 (4)
H7'	1.1039	0.4830	0.8413	0.033*
C8'	0.8677 (2)	0.60111 (16)	0.89035 (15)	0.0173 (4)
H8'	0.9166	0.6033	0.9819	0.021*
C8A'	0.6816 (3)	0.67103 (16)	0.84112 (15)	0.0204 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0366 (9)	0.0240 (8)	0.0316 (8)	0.0013 (6)	0.0141 (7)	0.0046 (6)
C2	0.0307 (9)	0.0211 (9)	0.0313 (9)	−0.0011 (7)	0.0153 (8)	0.0041 (7)
C3	0.0238 (9)	0.0213 (9)	0.0309 (10)	0.0001 (7)	0.0059 (7)	0.0016 (7)
C4	0.0276 (9)	0.0201 (9)	0.0197 (8)	0.0061 (7)	0.0044 (7)	0.0039 (7)
C4A	0.0249 (8)	0.0154 (9)	0.0210 (8)	0.0051 (6)	0.0070 (7)	0.0034 (6)
C5	0.0314 (9)	0.0201 (9)	0.0191 (8)	0.0057 (7)	0.0093 (7)	0.0058 (6)
C6	0.0285 (9)	0.0217 (9)	0.0261 (9)	0.0020 (7)	0.0128 (7)	0.0071 (7)
C7	0.0226 (8)	0.0221 (9)	0.0250 (9)	0.0006 (6)	0.0064 (7)	0.0049 (7)
C8	0.0240 (8)	0.0173 (9)	0.0220 (9)	0.0042 (6)	0.0074 (7)	0.0043 (6)
C8A	0.0227 (8)	0.0163 (9)	0.0211 (8)	0.0039 (6)	0.0085 (7)	0.0043 (6)
C1'	0.0215 (8)	0.0195 (9)	0.0214 (8)	−0.0026 (6)	0.0061 (7)	0.0046 (6)
C2'	0.0236 (8)	0.0229 (9)	0.0235 (9)	0.0015 (7)	0.0082 (7)	0.0043 (7)
C3'	0.0224 (8)	0.0230 (10)	0.0258 (9)	0.0017 (7)	0.0024 (7)	0.0081 (7)
C4'	0.0272 (9)	0.0209 (9)	0.0189 (8)	−0.0029 (7)	0.0035 (7)	0.0060 (6)
C4A'	0.0237 (8)	0.0162 (9)	0.0211 (8)	−0.0036 (6)	0.0046 (7)	0.0052 (6)
C5'	0.0295 (9)	0.0213 (9)	0.0197 (8)	−0.0041 (7)	0.0079 (7)	0.0051 (7)
C6'	0.0274 (9)	0.0225 (10)	0.0288 (9)	0.0004 (7)	0.0116 (7)	0.0028 (7)
C7'	0.0247 (9)	0.0210 (10)	0.0323 (10)	0.0024 (7)	0.0025 (7)	0.0061 (7)
C8'	0.0193 (8)	0.0148 (8)	0.0147 (7)	0.0006 (6)	0.0011 (6)	0.0026 (6)
C8A'	0.0222 (8)	0.0159 (9)	0.0217 (8)	−0.0033 (6)	0.0048 (7)	0.0044 (6)

Geometric parameters (Å, º) top

N1—C2	1.348 (2)	C1'—C2'	1.374 (2)
N1—C8A	1.395 (2)	C1'—C8A'	1.434 (2)
C2—C3	1.406 (2)	C2'—C3'	1.410 (2)
C2—H2	0.9500	C2'—H2'	0.9500
C3—C4	1.364 (2)	C3'—C4'	1.364 (2)
C3—H3	0.9500	C3'—H3'	0.9500
C4—C4A	1.420 (2)	C4'—C4A'	1.418 (2)
C4—H4	0.9500	C4'—H4'	0.9500
C4A—C5	1.418 (2)	C4A'—C5'	1.418 (2)
C4A—C8A	1.421 (2)	C4A'—C8A'	1.419 (2)
C5—C6	1.363 (2)	C5'—C6'	1.364 (2)
C5—H5	0.9500	C5'—H5'	0.9500
C6—C7	1.409 (2)	C6'—C7'	1.403 (2)
C6—H6	0.9500	C6'—H6'	0.9500
C7—C8	1.376 (2)	C7'—C8'	1.346 (2)
C7—H7	0.9500	C7'—H7'	0.9500
C8—C8A	1.432 (2)	C8'—C8A'	1.393 (2)
C8—C1'	1.494 (2)	C8'—H8'	0.9500

C2—N1—C8A	118.89 (15)	C2'—C1'—C8	120.02 (15)
N1—C2—C3	122.60 (15)	C8A'—C1'—C8	120.85 (14)
N1—C2—H2	118.7	C1'—C2'—C3'	121.44 (15)
C3—C2—H2	118.7	C1'—C2'—H2'	119.3
C4—C3—C2	119.48 (15)	C3'—C2'—H2'	119.3
C4—C3—H3	120.3	C4'—C3'—C2'	120.43 (15)
C2—C3—H3	120.3	C4'—C3'—H3'	119.8
C3—C4—C4A	120.15 (15)	C2'—C3'—H3'	119.8
C3—C4—H4	119.9	C3'—C4'—C4A'	120.27 (15)
C4A—C4—H4	119.9	C3'—C4'—H4'	119.9
C5—C4A—C4	122.25 (15)	C4A'—C4'—H4'	119.9
C5—C4A—C8A	119.47 (15)	C5'—C4A'—C4'	122.28 (15)
C4—C4A—C8A	118.27 (15)	C5'—C4A'—C8A'	118.09 (15)
C6—C5—C4A	120.44 (15)	C4'—C4A'—C8A'	119.63 (15)
C6—C5—H5	119.8	C6'—C5'—C4A'	120.54 (15)
C4A—C5—H5	119.8	C6'—C5'—H5'	119.7
C5—C6—C7	120.34 (15)	C4A'—C5'—H5'	119.7
C5—C6—H6	119.8	C5'—C6'—C7'	119.23 (15)
C7—C6—H6	119.8	C5'—C6'—H6'	120.4
C8—C7—C6	121.54 (15)	C7'—C6'—H6'	120.4
C8—C7—H7	119.2	C8'—C7'—C6'	122.44 (15)
C6—C7—H7	119.2	C8'—C7'—H7'	118.8
C7—C8—C8A	119.05 (15)	C6'—C7'—H7'	118.8
C7—C8—C1'	119.94 (15)	C7'—C8'—C8A'	119.33 (15)
C8A—C8—C1'	120.99 (14)	C7'—C8'—H8'	120.3
N1—C8A—C4A	120.58 (15)	C8A'—C8'—H8'	120.3
N1—C8A—C8	120.26 (14)	C8'—C8A'—C4A'	120.35 (15)
C4A—C8A—C8	119.15 (15)	C8'—C8A'—C1'	120.53 (14)
C2'—C1'—C8A'	119.12 (15)	C4A'—C8A'—C1'	119.10 (15)

C8A—N1—C2—C3	0.4 (3)	C7—C8—C1'—C8A'	−112.47 (18)
N1—C2—C3—C4	−1.1 (3)	C8A—C8—C1'—C8A'	69.1 (2)
C2—C3—C4—C4A	0.2 (2)	C8A'—C1'—C2'—C3'	−0.2 (2)
C3—C4—C4A—C5	−178.48 (15)	C8—C1'—C2'—C3'	−179.08 (15)
C3—C4—C4A—C8A	1.1 (2)	C1'—C2'—C3'—C4'	−0.2 (2)
C4—C4A—C5—C6	179.99 (15)	C2'—C3'—C4'—C4A'	0.1 (2)
C8A—C4A—C5—C6	0.4 (2)	C3'—C4'—C4A'—C5'	179.92 (15)
C4A—C5—C6—C7	0.0 (2)	C3'—C4'—C4A'—C8A'	0.3 (2)
C5—C6—C7—C8	0.2 (3)	C4'—C4A'—C5'—C6'	−178.28 (15)
C6—C7—C8—C8A	−0.7 (2)	C8A'—C4A'—C5'—C6'	1.4 (2)
C6—C7—C8—C1'	−179.14 (15)	C4A'—C5'—C6'—C7'	−0.1 (2)
C2—N1—C8A—C4A	1.0 (2)	C5'—C6'—C7'—C8'	−0.6 (3)
C2—N1—C8A—C8	179.75 (15)	C6'—C7'—C8'—C8A'	0.1 (2)
C5—C4A—C8A—N1	177.87 (14)	C7'—C8'—C8A'—C4A'	1.2 (2)
C4—C4A—C8A—N1	−1.7 (2)	C7'—C8'—C8A'—C1'	179.58 (14)
C5—C4A—C8A—C8	−0.9 (2)	C5'—C4A'—C8A'—C8'	−1.9 (2)
C4—C4A—C8A—C8	179.47 (14)	C4'—C4A'—C8A'—C8'	177.77 (14)
C7—C8—C8A—N1	−177.73 (14)	C5'—C4A'—C8A'—C1'	179.69 (13)
C1'—C8—C8A—N1	0.7 (2)	C4'—C4A'—C8A'—C1'	−0.7 (2)
C7—C8—C8A—C4A	1.1 (2)	C2'—C1'—C8A'—C8'	−177.81 (14)
C1'—C8—C8A—C4A	179.50 (14)	C8—C1'—C8A'—C8'	1.1 (2)
C7—C8—C1'—C2'	66.4 (2)	C2'—C1'—C8A'—C4A'	0.6 (2)
C8A—C8—C1'—C2'	−112.04 (18)	C8—C1'—C8A'—C4A'	179.48 (14)

Experimental details

Crystal data
Chemical formula	C₁₉H₁₃N
M_r	255.30
Crystal system, space group	Triclinic, P1
Temperature (K)	100
a, b, c (Å)	6.1778 (1), 10.0392 (2), 10.8828 (2)
α, β, γ (°)	104.537 (1), 106.435 (1), 90.002 (1)
V (Å³)	624.80 (2)
Z	2
Radiation type	Cu Kα
µ (mm⁻¹)	0.61
Crystal size (mm)	0.37 × 0.20 × 0.10

Data collection
Diffractometer	Bruker SMART CCD APEXII diffractometer
Absorption correction	Numerical (SADABS; Sheldrick, 2008)
T_min, T_max	0.806, 0.942
No. of measured, independent and observed [I > 2σ(I)] reflections	5783, 2058, 1678
R_int	0.011
(sin θ/λ)_max (Å⁻¹)	0.599

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.044, 0.131, 1.06
No. of reflections	2058
No. of parameters	181
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.38, −0.34

Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2005), SHELXTL (Sheldrick, 2008), Mercury (Macrae et al., 2008).

Acknowledgements

This work was partly supported by the SpF program of Kean University. The authors acknowledge support by NSF-CRIF Grant No. 0443538 for the X-ray diffractometer.

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