8-Iodo­quinolinium triiodide tetra­hydro­furan solvate

Son, J.-H.; Hoefelmeyer, J.D.

doi:10.1107/S1600536808031516

organic compounds

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ISSN: 2056-9890

Volume 64| Part 11| November 2008| Page o2077

doi:10.1107/S1600536808031516

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8-Iodoquinolinium triiodide tetrahydrofuran solvate

Jung-Ho Son ^a and James D. Hoefelmeyer ^a ^*

^aDepartment of Chemistry, The University of South Dakota, 414 E. Clark Street, Vermillion, SD 57069, USA
^*Correspondence e-mail: jhoefelm@usd.edu

(Received 4 August 2008; accepted 29 September 2008; online 4 October 2008)

The title compound, C₉H₇IN⁺·I₃⁻·C₄H₈O, was synthesized from 8-aminoquinoline using the Sandmeyer reaction. The 8-iodoquinolinium cation is essentially planar and the triiodide ion is almost linear. N—H⋯O hydrogen bonds, and intermolecular I⋯I [3.7100 (5) Å] and I⋯H interactions, between the cation, anion and solvent molecules result in the formation of sheets oriented parallel to the ( $[\overline{1}]$ 03) plane. Between the sheets, 8-iodoquinolinium and triiodide ions are stacked alternately, with I⋯C distances in the range ∼3.8–4.0 Å.

Related literature

For the synthesis, see: Lucas & Kennedy (1943 ); Sandmeyer (1884 ). For related structures, see: Son & Hoefelmeyer (2008 ); Svensson & Kloo (2003 ).

Experimental

Crystal data

C₉H₇IN⁺·I₃⁻·C₄H₈O
M_r = 708.86
Monoclinic, P 2₁ /n
a = 7.8674 (4) Å
b = 17.6510 (9) Å
c = 13.1465 (7) Å
β = 90.343 (1)°
V = 1825.59 (16) Å³
Z = 4
Mo Kα radiation
μ = 6.82 mm⁻¹
T = 100 (2) K
0.57 × 0.36 × 0.27 mm

Data collection

Bruker SMART APEXII diffractometer
Absorption correction: numerical (XPREP in SHELXTL; Sheldrick, 2008 ), T_min = 0.111, T_max = 0.262
18253 measured reflections
3363 independent reflections
3291 reflections with I > 2σ(I)
R_int = 0.079

Refinement

R[F² > 2σ(F²)] = 0.026
wR(F²) = 0.111
S = 0.97
3363 reflections
172 parameters
H-atom parameters constrained
Δρ_max = 0.55 e Å⁻³
Δρ_min = −2.63 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯I1	0.88	2.80	3.297 (4)	117
N1—H1⋯O1ⁱ	0.88	1.94	2.690 (5)	142
Symmetry code: (i) x, y, z+1.

Data collection: APEX2 (Bruker, 2006 ); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL; molecular graphics: ORTEP-3 (Farrugia, 1997 ) and Mercury (Macrae et al., 2006 ); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808031516/ci2653sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808031516/ci2653Isup2.hkl

checkCIF report

Comment top

8-Iodoquinoline is a starting material for the synthesis of 8-substituted quinoline derivatives. The molecule 8-iodoquinoline was synthesized starting from 8-aminoquinoline using the Sandmeyer reaction (Sandmeyer, 1884), similar to the synthesis of iodobenzene (Lucas & Kennedy, 1943). During its synthesis, two 8-iodoquinolinium salt crystals, 8-iodoquinolinium chloride dihydrate (Son & Hoefelmeyer, 2008) and 8-iodoquinolinium triiodide.THF were isolated. The synthesis, characterization and crystal structure of 8-iodoquinolinium triiodide^.THF are reported here.

The 8-iodoquinolinium cation is essentially planar (Fig. 1). The C9—C8—I1 angle is 121.9 (3) °, slightly larger than the ideal value of 120°. A weak intermolecular interaction is present between atom I1 of the cation and I2 of the triiodide anion; I1···I2(1 + x, y, 1 + z) = 3.7100 (5) Å. The geometry of triiodide is almost linear, with I2—I3 = 2.9416 (8) Å, I3—I4 = 2.9014 (8) Å and I4—I3—I2 angle is 177.445 (17)°. The shape resembles symmetric, free triiodide that typically occurs in the presence of bulky cations (Svensson & Kloo, 2003).

The 8-iodoquinolinium cation, I₃^- and THF form an extended sheet (Fig. 2) parallel to the (1 0 3) plane through I1···I2, I3···H4 (3.15 Å) and I4···H5 (3.09 Å) interactions and N—H···O hydrogen bonds (Table 1). Between the sheets, 8-iodoquinolinium and I₃^- ions are stacked alternately, with the I2···C2ⁱⁱ, I3···C8ⁱⁱ and I3···C9ⁱⁱ distances being 3.742 (5), 3.840 (4) and 3.838 (4) Å, respectively [symmetry code: (ii) -1/2 + x, 1/2 - y, -1/2 + z].

Related literature top

For the synthesis, see: Lucas & Kennedy (1943); Sandmeyer (1884). For related strcutures, see: Son & Hoefelmeyer (2008); Svensson & Kloo (2003). AUTHOR: if you wish to provide higher resolution figures please email new version(s) with your proof comments; Figure 1 in particular could be improved.

Experimental top

In a 500 ml beaker, a mixture of 8-aminoquinoline (10 g, 0.069 mol) and water (50 ml) was heated with stirring. While cooling the mixture in an ice bath, concentrated HCl (50 ml) was added to form a red solution. NaNO₂ (7.8 g, 0.113 mol) was dissolved in water (50 ml) and cooled in an ice bath separately. NaNO₂ solution was slowly transferred to the 8-aminoquinoline solution. Light brown precipitate formed during the addition step but eventually disappeared to form a reddish transparent solution. KI (17.9 g, 0.108 mol) was dissolved in water (25 ml) and added to the reaction mixture. Bubbles and brownish vapor evolved during addition. The solution turned to dark brown with black precipitate. The solution was refluxed with a watch glass on top of the beaker, and it became reddish brown with formation of a heavy organic layer; the black precipitate remained. After cooling and standing overnight, golden brown crystals of 8-iodoquinolinium chloride dihydrate had formed spontaneously in the solution. The mixture was neutralized upon addition of NaOH solution, which led to dissolution of the golden brown crystals and retention of the black precipitate. The liquid portion was separated from the black precipitate. 8-Iodoquinoline could be recoverd from the liquid portion upon extraction with toluene. The black precipitate was dissolved in THF and crystallized by pentane vapor diffusion to obtain the crystal of 8-iodoquinolinium triiodide^.THF [yield: 7.14 g (15%), m.p. 366–368 K]. ¹H NMR (acetone-d): 7.647–7.725 (dd, 1H, quin CH), 8.237–8.305 (dd, 1H, quin CH), 8.339–8.385 (dd, 1H, quin CH), 8.559–8.602 (dd, 1H, quin CH), 9.260–9.309 (dd, 1H, quin CH), 9.380–9.415 (dd, 1H, quin CH), 12.999 (br, 1H, NH). ¹³C NMR (acetone-d): 91.517 (quin C8), 124.089 (quin CH), 130.558 (quin C9/10), 130.817 (quin CH), 132.183 (quin CH), 138.064 (quin C9/10), 146.463 (quin CH), 147.614 (quin CH), 149.842 (quin CH). Elemental analysis result suggests that about 75% of THF depleted during storage. Analysis calculated for C₁₃H₁₅I₄NO: C 22.03, H 2.13, N 1.98%; found: C 19.30, H 1.32, N 2.19%.

Computing details top

Data collection: SMART (Bruker, 2003); cell refinement: SAINT (Bruker, 2003); data reduction: SAINT (Bruker, 2003); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. Asymmetric unit of 8-iodoquinolinium triiodide^.THF. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. Crystal structure of 8-iodoquinolinium triiodide^.THF, viewed along the c axis. Dotted lines denote hydrogen bonding and close contacts. Displacement ellipsoids are drawn at the 50% probability level.

8-Iodoquinolinium triiodide tetrahydrofuran solvate top

Crystal data top

C₉H₇IN⁺·I₃⁻·C₄H₈O	F(000) = 1280
M_r = 708.86	D_x = 2.579 Mg m⁻³
Monoclinic, P2₁/n	Melting point: 367 K
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 7.8674 (4) Å	Cell parameters from 9984 reflections
b = 17.6510 (9) Å	θ = 2.8–25.4°
c = 13.1465 (7) Å	µ = 6.82 mm⁻¹
β = 90.343 (1)°	T = 100 K
V = 1825.59 (16) Å³	Block, metallic violet
Z = 4	0.57 × 0.36 × 0.27 mm

Data collection top

Bruker SMART APEXII diffractometer	3363 independent reflections
Radiation source: fine-focus sealed tube	3291 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.079
ω scans	θ_max = 25.4°, θ_min = 1.9°
Absorption correction: numerical (XPREP in SHELXTL; Sheldrick, 2008) or (SADABS; Bruker, 2003)???	h = −9→9
T_min = 0.111, T_max = 0.262	k = −21→21
18253 measured reflections	l = −15→15

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)] = 0.027	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.111	H-atom parameters constrained
S = 0.98	w = 1/[σ²(F_o²) + (0.0437P)² + 2.836P] where P = (F_o² + 2F_c²)/3
3363 reflections	(Δ/σ)_max = 0.001
172 parameters	Δρ_max = 0.55 e Å⁻³
0 restraints	Δρ_min = −2.63 e Å⁻³

Crystal data top

C₉H₇IN⁺·I₃⁻·C₄H₈O	V = 1825.59 (16) Å³
M_r = 708.86	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 7.8674 (4) Å	µ = 6.82 mm⁻¹
b = 17.6510 (9) Å	T = 100 K
c = 13.1465 (7) Å	0.57 × 0.36 × 0.27 mm
β = 90.343 (1)°

Data collection top

Bruker SMART APEXII diffractometer	3363 independent reflections
Absorption correction: numerical (XPREP in SHELXTL; Sheldrick, 2008) or (SADABS; Bruker, 2003)???	3291 reflections with I > 2σ(I)
T_min = 0.111, T_max = 0.262	R_int = 0.079
18253 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.027	0 restraints
wR(F²) = 0.111	H-atom parameters constrained
S = 0.98	Δρ_max = 0.55 e Å⁻³
3363 reflections	Δρ_min = −2.63 e Å⁻³
172 parameters

Special details top

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
C2	0.2020 (7)	0.3301 (2)	0.9044 (4)	0.0231 (10)
H2	0.2425	0.3807	0.9094	0.028*
C3	0.0503 (6)	0.3161 (3)	0.8562 (4)	0.0265 (10)
H3	−0.0138	0.3565	0.8275	0.032*
C4	−0.0077 (5)	0.2427 (3)	0.8500 (3)	0.0229 (9)
H4	−0.1134	0.2322	0.8177	0.027*
C5	0.0356 (6)	0.1062 (3)	0.8839 (3)	0.0234 (9)
H5	−0.0706	0.0943	0.8531	0.028*
C6	0.1379 (6)	0.0497 (3)	0.9214 (3)	0.0231 (9)
H6	0.1035	−0.0017	0.9155	0.028*
C7	0.2952 (6)	0.0678 (3)	0.9690 (3)	0.0221 (9)
H7	0.3640	0.0281	0.9954	0.027*
C8	0.3493 (5)	0.1402 (3)	0.9775 (3)	0.0181 (8)
C9	0.2463 (5)	0.1992 (3)	0.9385 (3)	0.0167 (8)
C10	0.0900 (6)	0.1829 (3)	0.8917 (3)	0.0197 (9)
C11	0.5434 (6)	0.3891 (3)	0.1252 (3)	0.0233 (9)
H11A	0.6024	0.3486	0.1637	0.028*
H11B	0.4297	0.3972	0.1551	0.028*
C12	0.6463 (6)	0.4619 (3)	0.1272 (4)	0.0250 (9)
H12A	0.7212	0.4638	0.1879	0.030*
H12B	0.5708	0.5068	0.1275	0.030*
C13	0.7520 (6)	0.4587 (3)	0.0285 (3)	0.0243 (9)
H13A	0.7269	0.5028	−0.0158	0.029*
H13B	0.8753	0.4578	0.0439	0.029*
C14	0.6948 (5)	0.3849 (3)	−0.0216 (3)	0.0237 (9)
H14A	0.6885	0.3907	−0.0965	0.028*
H14B	0.7749	0.3433	−0.0052	0.028*
I1	0.58420 (4)	0.162595 (15)	1.04875 (2)	0.02127 (14)
I2	−0.00026 (4)	0.166821 (16)	0.18354 (2)	0.02404 (14)
I3	0.05172 (4)	0.330240 (15)	0.21544 (2)	0.01836 (14)
I4	0.11961 (4)	0.488485 (17)	0.25933 (2)	0.02294 (14)
N1	0.2941 (4)	0.2734 (2)	0.9445 (3)	0.0182 (7)
H1	0.3897	0.2845	0.9762	0.022*
O1	0.5292 (4)	0.36930 (18)	0.0195 (2)	0.0210 (6)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C2	0.026 (3)	0.017 (2)	0.027 (2)	−0.0006 (16)	0.003 (2)	0.0016 (16)
C3	0.022 (2)	0.034 (3)	0.023 (2)	0.012 (2)	0.0013 (18)	0.005 (2)
C4	0.015 (2)	0.035 (3)	0.018 (2)	−0.0014 (18)	−0.0022 (15)	−0.0022 (18)
C5	0.022 (2)	0.029 (2)	0.020 (2)	−0.0101 (19)	0.0027 (16)	−0.0036 (18)
C6	0.030 (2)	0.017 (2)	0.022 (2)	−0.0091 (18)	0.0006 (17)	−0.0029 (17)
C7	0.025 (2)	0.021 (2)	0.020 (2)	0.0005 (17)	0.0047 (17)	−0.0024 (17)
C8	0.0144 (19)	0.025 (2)	0.0151 (19)	0.0012 (18)	0.0005 (15)	−0.0010 (17)
C9	0.0149 (19)	0.022 (2)	0.0128 (17)	0.0022 (17)	0.0027 (14)	0.0011 (16)
C10	0.022 (2)	0.022 (2)	0.014 (2)	−0.0064 (17)	0.0038 (16)	−0.0040 (17)
C11	0.022 (2)	0.029 (2)	0.019 (2)	−0.0016 (18)	0.0018 (16)	−0.0011 (18)
C12	0.022 (2)	0.023 (2)	0.030 (2)	−0.0029 (18)	−0.0053 (18)	−0.0038 (19)
C13	0.020 (2)	0.026 (2)	0.027 (2)	−0.0063 (19)	−0.0055 (17)	0.0035 (19)
C14	0.017 (2)	0.032 (3)	0.022 (2)	−0.0001 (18)	0.0041 (17)	0.0014 (18)
I1	0.0187 (2)	0.0219 (2)	0.0232 (2)	0.00115 (10)	−0.00448 (14)	0.00111 (10)
I2	0.0264 (2)	0.0248 (2)	0.0209 (2)	−0.00137 (10)	0.00150 (15)	−0.00241 (10)
I3	0.0143 (2)	0.0245 (2)	0.0163 (2)	0.00172 (9)	−0.00029 (13)	0.00112 (9)
I4	0.0240 (2)	0.0216 (2)	0.0232 (2)	0.00220 (10)	−0.00198 (14)	0.00159 (10)
N1	0.0137 (17)	0.024 (2)	0.0172 (17)	0.0021 (14)	0.0010 (13)	−0.0015 (14)
O1	0.0182 (15)	0.0214 (16)	0.0233 (15)	−0.0030 (12)	0.0010 (12)	−0.0034 (13)

Geometric parameters (Å, º) top

C2—N1	1.343 (6)	C9—C10	1.401 (7)
C2—C3	1.370 (8)	C11—O1	1.436 (5)
C2—H2	0.95	C11—C12	1.519 (6)
C3—C4	1.375 (7)	C11—H11A	0.99
C3—H3	0.95	C11—H11B	0.99
C4—C10	1.415 (7)	C12—C13	1.547 (6)
C4—H4	0.95	C12—H12A	0.99
C5—C6	1.372 (7)	C12—H12B	0.99
C5—C10	1.423 (6)	C13—C14	1.527 (6)
C5—H5	0.95	C13—H13A	0.99
C6—C7	1.419 (7)	C13—H13B	0.99
C6—H6	0.95	C14—O1	1.440 (5)
C7—C8	1.352 (6)	C14—H14A	0.99
C7—H7	0.95	C14—H14B	0.99
C8—C9	1.413 (6)	I2—I3	2.9430 (4)
C8—I1	2.104 (4)	I3—I4	2.9011 (4)
C9—N1	1.364 (6)	N1—H1	0.88

N1—C2—C3	120.9 (4)	O1—C11—H11A	110.7
N1—C2—H2	119.5	C12—C11—H11A	110.7
C3—C2—H2	119.5	O1—C11—H11B	110.7
C2—C3—C4	119.0 (4)	C12—C11—H11B	110.7
C2—C3—H3	120.5	H11A—C11—H11B	108.8
C4—C3—H3	120.5	C11—C12—C13	104.1 (4)
C3—C4—C10	120.0 (4)	C11—C12—H12A	110.9
C3—C4—H4	120.0	C13—C12—H12A	110.9
C10—C4—H4	120.0	C11—C12—H12B	110.9
C6—C5—C10	119.4 (4)	C13—C12—H12B	110.9
C6—C5—H5	120.3	H12A—C12—H12B	109.0
C10—C5—H5	120.3	C14—C13—C12	103.6 (3)
C5—C6—C7	120.1 (4)	C14—C13—H13A	111.0
C5—C6—H6	119.9	C12—C13—H13A	111.0
C7—C6—H6	119.9	C14—C13—H13B	111.0
C8—C7—C6	121.6 (4)	C12—C13—H13B	111.0
C8—C7—H7	119.2	H13A—C13—H13B	109.0
C6—C7—H7	119.2	O1—C14—C13	105.4 (3)
C7—C8—C9	119.1 (4)	O1—C14—H14A	110.7
C7—C8—I1	119.3 (3)	C13—C14—H14A	110.7
C9—C8—I1	121.6 (3)	O1—C14—H14B	110.7
N1—C9—C10	117.6 (4)	C13—C14—H14B	110.7
N1—C9—C8	121.9 (4)	H14A—C14—H14B	108.8
C10—C9—C8	120.5 (4)	I4—I3—I2	175.753 (14)
C9—C10—C4	119.4 (4)	C2—N1—C9	123.0 (4)
C9—C10—C5	119.3 (5)	C2—N1—H1	118.5
C4—C10—C5	121.3 (4)	C9—N1—H1	118.5
O1—C11—C12	105.2 (3)	C11—O1—C14	104.5 (3)

N1—C2—C3—C4	0.5 (7)	C8—C9—C10—C5	0.1 (6)
C2—C3—C4—C10	−0.9 (7)	C3—C4—C10—C9	−0.4 (7)
C10—C5—C6—C7	1.1 (7)	C3—C4—C10—C5	−178.2 (4)
C5—C6—C7—C8	−0.9 (7)	C6—C5—C10—C9	−0.7 (6)
C6—C7—C8—C9	0.3 (6)	C6—C5—C10—C4	177.1 (4)
C6—C7—C8—I1	−179.9 (3)	O1—C11—C12—C13	−25.5 (4)
C7—C8—C9—N1	−179.8 (4)	C11—C12—C13—C14	1.4 (5)
I1—C8—C9—N1	0.4 (5)	C12—C13—C14—O1	23.0 (4)
C7—C8—C9—C10	0.0 (6)	C3—C2—N1—C9	1.4 (7)
I1—C8—C9—C10	−179.8 (3)	C10—C9—N1—C2	−2.7 (6)
N1—C9—C10—C4	2.2 (6)	C8—C9—N1—C2	177.1 (4)
C8—C9—C10—C4	−177.7 (4)	C12—C11—O1—C14	41.1 (4)
N1—C9—C10—C5	−180.0 (4)	C13—C14—O1—C11	−40.2 (4)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···I1	0.88	2.80	3.297 (4)	117
N1—H1···O1ⁱ	0.88	1.94	2.690 (5)	142

Symmetry code: (i) x, y, z+1.

Experimental details

Crystal data
Chemical formula	C₉H₇IN⁺·I₃⁻·C₄H₈O
M_r	708.86
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	100
a, b, c (Å)	7.8674 (4), 17.6510 (9), 13.1465 (7)
β (°)	90.343 (1)
V (Å³)	1825.59 (16)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	6.82
Crystal size (mm)	0.57 × 0.36 × 0.27

Data collection
Diffractometer	Bruker SMART APEXII diffractometer
Absorption correction	Numerical (XPREP in SHELXTL; Sheldrick, 2008) or (SADABS; Bruker, 2003)???
T_min, T_max	0.111, 0.262
No. of measured, independent and observed [I > 2σ(I)] reflections	18253, 3363, 3291
R_int	0.079
(sin θ/λ)_max (Å⁻¹)	0.602

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.027, 0.111, 0.98
No. of reflections	3363
No. of parameters	172
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.55, −2.63

Computer programs: SMART (Bruker, 2003), SAINT (Bruker, 2003), SHELXTL (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2006).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···I1	0.88	2.80	3.297 (4)	117
N1—H1···O1ⁱ	0.88	1.94	2.690 (5)	142

Symmetry code: (i) x, y, z+1.

Acknowledgements

This work was supported by funding from the South Dakota 2010 Initiative, Center for Research and Development of Light-Activated Materials. Purchase of the X-ray diffractometer was made possible with funds from the National Science Foundation (EPS-0554609).

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