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Acta Crystallogr Sect E Struct Rep Online. 2010 June 1; 66(Pt 6): o1388–o1389.
Published online 2010 May 19. doi:  10.1107/S1600536810017903
PMCID: PMC2979642

8a-Methyl-5,6,8,8a,9,10-hexa­hydro-10,12a-epoxy­isoindolo[1,2-a]isoquinolinium iodide

Abstract

The title compound, C17H18NO+·I, is an adduct resulting from an intra­molecular Diels–Alder reaction of methallyl chloride with 3,4-dihydro-1-furylisoquinoline. The cation comprises a fused penta­cyclic system containing three five-membered rings (dihydro­pyrrole, dihydro­furan and tetra­hydro­furan) and two six-membered rings (tetra­hydro­pyridine and benzene). The five-membered rings have the usual envelope conformations, and the central six-membered tetra­hydro­pyridine ring adopts the unsymmetrical half-boat conformation. In the crystal, cations and iodide anions are bound by weak inter­molecular hydrogen-bonding inter­actions into a three-dimensional framework.

Related literature

For general background to the method proposed by our group for obtaining hydrogenated isoindolo[2,1-a]isoquinolines using commercially available furfurals and phenethyl­amines as starting materials, see: Zubkov et al. (2004 [triangle]); Boltukhina et al. (2006 [triangle]). For related structures, see: Tagmazyan et al. (1976 [triangle], 1977 [triangle]); Ahmad et al. (1987 [triangle]); Rasheed et al. (1991 [triangle]); Zubkov et al. (2009 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o1388-scheme1.jpg

Experimental

Crystal data

  • C17H18NO+·I
  • M r = 379.22
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o1388-efi1.jpg
  • a = 15.5047 (6) Å
  • b = 8.0757 (3) Å
  • c = 25.1874 (12) Å
  • β = 104.204 (1)°
  • V = 3057.3 (2) Å3
  • Z = 8
  • Mo Kα radiation
  • μ = 2.09 mm−1
  • T = 100 K
  • 0.30 × 0.20 × 0.15 mm

Data collection

  • Bruker APEXII CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 2003 [triangle]) T min = 0.573, T max = 0.745
  • 18881 measured reflections
  • 4450 independent reflections
  • 4123 reflections with I > 2σ(I)
  • R int = 0.031

Refinement

  • R[F 2 > 2σ(F 2)] = 0.025
  • wR(F 2) = 0.054
  • S = 1.00
  • 4450 reflections
  • 182 parameters
  • H-atom parameters constrained
  • Δρmax = 0.48 e Å−3
  • Δρmin = −0.94 e Å−3

Data collection: APEX2 (Bruker, 2005 [triangle]); cell refinement: SAINT-Plus (Bruker, 2001 [triangle]); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810017903/rk2205sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810017903/rk2205Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

Comment

Recently our group has proposed an efficient approach (Zubkov et al., 2009) to potentially bioactive substances - hydrogenated isoindolo[2,1-a]isoquinolines using commercially available furfurals and phenethylamines as starting materials (Boltukhina et al., 2006). The intramolecular furan Diels–Alder reaction (IMDAF) (Zubkov et al., 2004) between unsaturated acid derivatives and the furan core of the amines was the key step of the transformations mentioned above.

Trying to apply our chemistry to target natural products, we were attracted to isoindoloisoquinoline alkaloids. Today, there are three known natural alkaloids containing the isoindolo[2,1-a]isoquinoline skeleton - Nuevamine, Jamtine (and its N-oxide) and Hirsutine (Rasheed et al., 1991).

This work realizes aforementioned approach and describes the structure of an alkaloid-like IMDAF product I containing the nodal iminium nitrogen atom (Tagmazyan et al., 1976; Ahmad et al., 1987).

Compound I, [C17H18NO+][I-], is the adduct of intramolecular Diels–Alder reaction of methallyl chloride with 3,4-dihydro-1-furylisoquinoline. The cation of I comprises a fused pentacyclic system containing three five-membered rings (dihydropyrrole, dihydrofuran and tetrahydrofuran) and two six-membered rings (tetrahydropyridine and benzene) (Fig. 1). The five-membered rings have usual envelope conformations, and the central six-membered tetrahydropyridine ring adopts the unsymmetrical half-boat conformation. The nitrogen N7 atom has a trigonal-planar geometry (sum of the bond angles is 359.5°). The dihedral angle between the planes of the dihydropyrrole (N7/C8/C12A/C12B) and benzene rings is 20.1 (1)°.

The cation of I possesses three asymmetric centers at the C8A, C10 and C12A carbon atoms and can have potentially eight diastereomers. The crystal of I is racemic and consists of enantiomeric pairs with the following relative configuration of the centers: rac-8 AR*,10R*,12 AR*.

The crystal packing of the cations of I is stacking along the b axis (Fig. 2). In the crystal, the cations and iodide anions are bound by the weak intermolecular hydrogen bonding interactions into 3-dimensional framework (Fig. 2, Table 1).

Experimental

Potassium iodide (3.1 g, 11 mmol) and methallylchloride (0.8 ml, 8.25 mmol) were added to a solution of 1-furyl-3,4-dihydroisoquinoline (1.08 g, 5.5 mmol) in dioxane (50 ml). The reaction mixture was refluxed for 5 h (monitoring by TLC until disappearance of the starting compound sport). At the end of the reaction, solvent was removed under reduced pressure and the residue was crystallized from ethyl acetate–ethanol mixture to give 0.35 g of isoquinolinium iodide as brown prisms (Fig. 3). Yield is 17%. The single crystals of product I were obtained by slow crystallization from acetonitrile (yield 73%). M.p. = 451–453 K. Rf = 0.3 (ethyl acetate–ethanol, 4:1). IR (KBr), ν/cm-1: 1632, 2361, 2947, 3399. 1H NMR (CDCl3, 400 MHz, 300 K): δ = 1.33 (s, 3H, Me), 1.38 (d. 1H, H9 (endo), J9A,9B = 11.8), 2.50 (dd, 1H, H9 (exo), J9(exo),10 = 4.4, J9A,9B = 11.8), 3.33 (ddd, 1H, H5B, J5B,6A = 2.5, J5B,6B = 5.6, J5A,5B = 16.8), 4.01 (m, 1H, H5A), 4.15 (m, 1H, H6A), 4.32 (d, 1H, H8B, J8A,8B = 14.0), 4.84 (d, 1H, H8A, J8A,8B = 14.0), 5.04 (ddd, 1H, H6B, J6B,5A = 3.1, J6B,5B = 7.5, J6A,6B = 15.0), 5.36 (dd, 2H, H10, J10,11 = 1.2, J9(exo),10 = 4.4), 6.79 (d, 1H, H11, J10,11 = 1.2, J11,12 = 5.6), 6.83 (d, 1H, H12, J11,12 = 5.6), 7.50 (br, 1H, H2, J1,2 = J2,3 = 7.5), 7.54 (d, 1H, H4, J3,4 = 7.5), 7.82 (t, 1H, H3, J2,3 = J3,4 = 7.5), 7.85 (d, 1H, H1, J1,2 = 7.5). Anal. Calcd for C17H18INO: C, 53.84; H, 4.78; N, 3.69. Found: C, 53.67; H, 4.65; N, 3.62.

Refinement

The hydrogen atoms were placed in calculated positions with C—H = 0.95–1.00Å and refined in the riding model with fixed isotropic displacement parameters - Uiso(H) = 1.5Ueq(C) for CH3-group and Uiso(H) = 1.2Ueq(C) for the other groups.

Figures

Fig. 1.
Molecular structure of I. Displacement ellipsoids are shown at the 50% probability level. H atoms are presented as a small spheres of arbitrary radius.
Fig. 2.
Crystal packing of I along the b axis. Dashed lines indicate the weak intermolecular C—H···I hydrogen bonding interactions.
Fig. 3.
Tandem alkylation/[4+2] cycloaddition reaction of methallyl chloride with 3,4-dihydro-1-furylisoquinoline.

Crystal data

C17H18NO+·IF(000) = 1504
Mr = 379.22Dx = 1.648 Mg m3
Monoclinic, C2/cMelting point: 452 K
Hall symbol: -C 2ycMo Kα radiation, λ = 0.71073 Å
a = 15.5047 (6) ÅCell parameters from 7921 reflections
b = 8.0757 (3) Åθ = 2.7–32.5°
c = 25.1874 (12) ŵ = 2.09 mm1
β = 104.204 (1)°T = 100 K
V = 3057.3 (2) Å3Prism, orange
Z = 80.30 × 0.20 × 0.15 mm

Data collection

Bruker APEXII CCD diffractometer4450 independent reflections
Radiation source: fine-focus sealed tube4123 reflections with I > 2σ(I)
graphiteRint = 0.031
[var phi] and ω scansθmax = 30.0°, θmin = 1.7°
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)h = −21→21
Tmin = 0.573, Tmax = 0.745k = −11→11
18881 measured reflectionsl = −35→35

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.025Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.054H-atom parameters constrained
S = 1.00w = 1/[σ2(Fo2) + (0.0195P)2 + 6.6P] where P = (Fo2 + 2Fc2)/3
4450 reflections(Δ/σ)max = 0.002
182 parametersΔρmax = 0.48 e Å3
0 restraintsΔρmin = −0.94 e Å3

Special details

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)

xyzUiso*/Ueq
I10.325921 (8)0.080703 (16)0.405918 (5)0.02178 (4)
O10.45929 (8)0.66340 (17)0.33020 (5)0.0191 (3)
C10.61820 (12)0.8559 (2)0.27922 (7)0.0184 (3)
H10.58710.75670.26630.022*
C1A0.63271 (12)0.9011 (2)0.33406 (7)0.0165 (3)
C20.64969 (13)0.9574 (2)0.24349 (8)0.0206 (4)
H20.63920.92920.20580.025*
C30.69669 (13)1.1005 (2)0.26325 (8)0.0226 (4)
H30.71781.17000.23870.027*
C40.71330 (13)1.1433 (2)0.31838 (8)0.0206 (4)
H40.74721.23950.33140.025*
C4A0.68027 (12)1.0454 (2)0.35434 (8)0.0183 (3)
C50.69532 (13)1.0806 (2)0.41463 (8)0.0214 (4)
H5A0.71061.19890.42170.026*
H5B0.74581.01340.43530.026*
C60.61228 (13)1.0400 (2)0.43404 (8)0.0205 (4)
H6A0.62551.04750.47450.025*
H6B0.56461.12040.41840.025*
N70.58279 (10)0.8714 (2)0.41628 (6)0.0174 (3)
C80.52789 (12)0.7704 (2)0.44453 (7)0.0192 (3)
H8A0.46590.81140.43650.023*
H8B0.55300.77050.48470.023*
C8A0.53246 (12)0.5980 (2)0.42045 (7)0.0175 (3)
C90.44431 (13)0.4996 (3)0.40199 (8)0.0228 (4)
H9A0.39450.55750.41230.027*
H9B0.45010.38660.41770.027*
C100.43173 (13)0.4959 (3)0.33880 (8)0.0223 (4)
H100.37040.46610.31740.027*
C110.50568 (14)0.3957 (2)0.32470 (8)0.0221 (4)
H110.50080.28760.30940.027*
C120.57905 (12)0.4890 (2)0.33795 (7)0.0187 (3)
H120.63650.46470.33290.022*
C12A0.54908 (11)0.6422 (2)0.36281 (7)0.0158 (3)
C12B0.59353 (12)0.8077 (2)0.37104 (7)0.0162 (3)
C130.60762 (13)0.4998 (3)0.45782 (8)0.0225 (4)
H13A0.59330.48030.49310.034*
H13B0.66320.56280.46370.034*
H13C0.61460.39340.44060.034*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
I10.02024 (6)0.02454 (7)0.01967 (6)−0.00275 (5)0.00320 (4)−0.00284 (5)
O10.0163 (6)0.0212 (6)0.0176 (6)0.0003 (5)0.0001 (5)0.0018 (5)
C10.0191 (8)0.0182 (8)0.0174 (8)−0.0002 (7)0.0039 (6)−0.0004 (7)
C1A0.0178 (8)0.0158 (8)0.0161 (8)0.0015 (6)0.0044 (6)0.0012 (6)
C20.0208 (8)0.0240 (9)0.0180 (8)0.0010 (7)0.0067 (7)0.0004 (7)
C30.0219 (9)0.0225 (9)0.0249 (9)0.0008 (7)0.0087 (7)0.0048 (7)
C40.0193 (8)0.0174 (8)0.0256 (9)−0.0007 (7)0.0064 (7)−0.0006 (7)
C4A0.0163 (8)0.0177 (8)0.0199 (8)0.0007 (6)0.0028 (6)−0.0009 (6)
C50.0230 (9)0.0215 (9)0.0193 (8)−0.0031 (7)0.0043 (7)−0.0033 (7)
C60.0268 (9)0.0176 (8)0.0183 (8)−0.0021 (7)0.0079 (7)−0.0035 (7)
N70.0200 (7)0.0164 (7)0.0162 (7)−0.0001 (6)0.0051 (6)0.0003 (6)
C80.0213 (8)0.0213 (9)0.0161 (8)−0.0003 (7)0.0066 (6)0.0006 (7)
C8A0.0178 (8)0.0191 (8)0.0157 (8)−0.0016 (6)0.0045 (6)0.0011 (6)
C90.0215 (9)0.0265 (10)0.0209 (9)−0.0070 (7)0.0058 (7)0.0003 (8)
C100.0199 (8)0.0245 (10)0.0217 (9)−0.0063 (7)0.0032 (7)−0.0005 (7)
C110.0273 (9)0.0190 (9)0.0191 (8)−0.0031 (7)0.0038 (7)−0.0008 (7)
C120.0206 (8)0.0184 (8)0.0172 (8)0.0014 (7)0.0046 (7)−0.0002 (7)
C12A0.0152 (7)0.0171 (8)0.0151 (7)−0.0011 (6)0.0034 (6)0.0010 (6)
C12B0.0167 (8)0.0164 (8)0.0147 (7)0.0013 (6)0.0021 (6)0.0006 (6)
C130.0246 (9)0.0242 (10)0.0178 (8)0.0029 (7)0.0036 (7)0.0047 (7)

Geometric parameters (Å, °)

O1—C12A1.443 (2)N7—C81.481 (2)
O1—C101.451 (2)C8—C8A1.527 (3)
C1—C21.391 (3)C8—H8A0.9900
C1—C1A1.393 (2)C8—H8B0.9900
C1—H10.9500C8A—C131.528 (3)
C1A—C4A1.406 (3)C8A—C91.550 (3)
C1A—C12B1.443 (2)C8A—C12A1.576 (2)
C2—C31.391 (3)C9—C101.555 (3)
C2—H20.9500C9—H9A0.9900
C3—C41.392 (3)C9—H9B0.9900
C3—H30.9500C10—C111.515 (3)
C4—C4A1.392 (3)C10—H101.0000
C4—H40.9500C11—C121.337 (3)
C4A—C51.506 (3)C11—H110.9500
C5—C61.521 (3)C12—C12A1.510 (3)
C5—H5A0.9900C12—H120.9500
C5—H5B0.9900C12A—C12B1.495 (3)
C6—N71.470 (2)C13—H13A0.9800
C6—H6A0.9900C13—H13B0.9800
C6—H6B0.9900C13—H13C0.9800
N7—C12B1.298 (2)
C12A—O1—C1094.73 (13)C8—C8A—C13109.33 (15)
C2—C1—C1A119.36 (18)C8—C8A—C9117.58 (16)
C2—C1—H1120.3C13—C8A—C9113.69 (16)
C1A—C1—H1120.3C8—C8A—C12A101.17 (14)
C1—C1A—C4A121.36 (17)C13—C8A—C12A114.35 (15)
C1—C1A—C12B120.78 (17)C9—C8A—C12A99.85 (14)
C4A—C1A—C12B117.70 (16)C8A—C9—C10101.35 (14)
C1—C2—C3119.60 (18)C8A—C9—H9A111.5
C1—C2—H2120.2C10—C9—H9A111.5
C3—C2—H2120.2C8A—C9—H9B111.5
C2—C3—C4121.04 (18)C10—C9—H9B111.5
C2—C3—H3119.5H9A—C9—H9B109.3
C4—C3—H3119.5O1—C10—C11101.25 (15)
C4A—C4—C3120.02 (18)O1—C10—C999.63 (15)
C4A—C4—H4120.0C11—C10—C9109.76 (16)
C3—C4—H4120.0O1—C10—H10114.8
C4—C4A—C1A118.58 (18)C11—C10—H10114.8
C4—C4A—C5123.94 (17)C9—C10—H10114.8
C1A—C4A—C5117.44 (17)C12—C11—C10106.70 (17)
C4A—C5—C6110.45 (16)C12—C11—H11126.7
C4A—C5—H5A109.6C10—C11—H11126.7
C6—C5—H5A109.6C11—C12—C12A103.62 (16)
C4A—C5—H5B109.6C11—C12—H12128.2
C6—C5—H5B109.6C12A—C12—H12128.2
H5A—C5—H5B108.1O1—C12A—C12B108.67 (14)
N7—C6—C5109.06 (15)O1—C12A—C12102.32 (14)
N7—C6—H6A109.9C12B—C12A—C12127.70 (16)
C5—C6—H6A109.9O1—C12A—C8A101.44 (13)
N7—C6—H6B109.9C12B—C12A—C8A104.40 (14)
C5—C6—H6B109.9C12—C12A—C8A109.46 (15)
H6A—C6—H6B108.3N7—C12B—C1A121.63 (17)
C12B—N7—C6122.46 (16)N7—C12B—C12A108.79 (15)
C12B—N7—C8114.58 (16)C1A—C12B—C12A129.10 (16)
C6—N7—C8122.45 (15)C8A—C13—H13A109.5
N7—C8—C8A102.91 (14)C8A—C13—H13B109.5
N7—C8—H8A111.2H13A—C13—H13B109.5
C8A—C8—H8A111.2C8A—C13—H13C109.5
N7—C8—H8B111.2H13A—C13—H13C109.5
C8A—C8—H8B111.2H13B—C13—H13C109.5
H8A—C8—H8B109.1
C2—C1—C1A—C4A−1.4 (3)C10—C11—C12—C12A2.8 (2)
C2—C1—C1A—C12B173.85 (17)C10—O1—C12A—C12B−169.84 (14)
C1A—C1—C2—C31.3 (3)C10—O1—C12A—C1252.90 (15)
C1—C2—C3—C40.4 (3)C10—O1—C12A—C8A−60.19 (15)
C2—C3—C4—C4A−2.1 (3)C11—C12—C12A—O1−35.95 (18)
C3—C4—C4A—C1A2.0 (3)C11—C12—C12A—C12B−161.61 (17)
C3—C4—C4A—C5179.45 (18)C11—C12—C12A—C8A71.05 (18)
C1—C1A—C4A—C4−0.2 (3)C8—C8A—C12A—O1−86.84 (15)
C12B—C1A—C4A—C4−175.63 (16)C13—C8A—C12A—O1155.78 (15)
C1—C1A—C4A—C5−177.87 (17)C9—C8A—C12A—O134.03 (17)
C12B—C1A—C4A—C56.7 (2)C8—C8A—C12A—C12B26.06 (17)
C4—C4A—C5—C6142.02 (19)C13—C8A—C12A—C12B−91.31 (18)
C1A—C4A—C5—C6−40.5 (2)C9—C8A—C12A—C12B146.94 (15)
C4A—C5—C6—N751.2 (2)C8—C8A—C12A—C12165.56 (14)
C5—C6—N7—C12B−32.4 (2)C13—C8A—C12A—C1248.2 (2)
C5—C6—N7—C8156.17 (16)C9—C8A—C12A—C12−73.57 (17)
C12B—N7—C8—C8A20.2 (2)C6—N7—C12B—C1A−2.2 (3)
C6—N7—C8—C8A−167.72 (16)C8—N7—C12B—C1A169.88 (16)
N7—C8—C8A—C1394.15 (16)C6—N7—C12B—C12A−174.87 (16)
N7—C8—C8A—C9−134.27 (16)C8—N7—C12B—C12A−2.8 (2)
N7—C8—C8A—C12A−26.83 (17)C1—C1A—C12B—N7−158.84 (18)
C8—C8A—C9—C10112.08 (18)C4A—C1A—C12B—N716.6 (3)
C13—C8A—C9—C10−118.35 (17)C1—C1A—C12B—C12A12.3 (3)
C12A—C8A—C9—C103.87 (18)C4A—C1A—C12B—C12A−172.30 (17)
C12A—O1—C10—C11−50.15 (15)O1—C12A—C12B—N792.29 (17)
C12A—O1—C10—C962.39 (15)C12—C12A—C12B—N7−144.62 (18)
C8A—C9—C10—O1−40.39 (17)C8A—C12A—C12B—N7−15.34 (19)
C8A—C9—C10—C1165.35 (19)O1—C12A—C12B—C1A−79.7 (2)
O1—C10—C11—C1230.66 (19)C12—C12A—C12B—C1A43.4 (3)
C9—C10—C11—C12−74.0 (2)C8A—C12A—C12B—C1A172.67 (17)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C2—H2···I1i0.953.233.999 (2)139
C6—H6A···I1ii0.993.104.028 (2)157
C8—H8A···I1iii0.993.043.942 (2)153
C8—H8B···I1ii0.993.174.072 (2)153
C9—H9B···I10.993.103.862 (2)135
C12—H12···I1iv0.953.203.862 (2)128
C13—H13B···I1iv0.983.213.970 (2)136

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: RK2205).

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