(E,E)-1-Methyl-2,6-distyrylpyridinium iodide

Penthala, N.R.; Eldridge, J.; Reddy, T.R.Y.; Parkin, S.; Crooks, P.A.

doi:10.1107/S1600536810018519

organic compounds

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ISSN: 2056-9890

Volume 66| Part 7| July 2010| Page o1793

doi:10.1107/S1600536810018519

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(E,E)-1-Methyl-2,6-distyrylpyridinium iodide

Narsimha Reddy Penthala,^a Joshua Eldridge,^a Thirupathi Reddy Yerram Reddy,^a Sean Parkin ^b and Peter A. Crooks ^a ^*

^aDepartment of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536, USA, and ^bDepartment of Chemistry, University of Kentucky, Lexington, KY 40506, USA
^*Correspondence e-mail: pcrooks@uky.edu

(Received 3 March 2010; accepted 18 May 2010; online 26 June 2010)

In the title compound, C₂₂H₂₀N⁺·I⁻, the dihedral angles between the central pyridine ring and two outer benzene rings are 15.30 (10) and 11.82 (11)°. There are intermolecular π–π stacking interactions between the nearest phenyl ring over an inversion-related pyridyl ring, the shortest centroid–centroid distance being 3.672 (3) Å. The crystal structure of the compound indicates the 2,6-distyryl substituents have an E configuration.

Related literature

For the conventional synthesis, see: Stanek et al. (1952 ). For the activity of related compounds, see Zheng et al. (2005 ).

Experimental

Crystal data

C₂₂H₂₀N⁺·I⁻
M_r = 425.29
Monoclinic, C 2/c
a = 18.7309 (4) Å
b = 9.5687 (2) Å
c = 19.9829 (4) Å
β = 90.279 (1)°
V = 3581.50 (13) Å³
Z = 8
Cu Kα radiation
μ = 14.04 mm⁻¹
T = 90 K
0.18 × 0.14 × 0.08 mm

Data collection

Bruker X8 Proteum diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2001 ) T_min = 0.211, T_max = 0.400
24972 measured reflections
3303 independent reflections
3286 reflections with I > 2σ(I)
R_int = 0.043

Refinement

R[F² > 2σ(F²)] = 0.021
wR(F²) = 0.055
S = 1.09
3303 reflections
219 parameters
H-atom parameters constrained
Δρ_max = 0.58 e Å⁻³
Δρ_min = −0.49 e Å⁻³

Data collection: APEX2 (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and local procedures.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810018519/nk2028sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810018519/nk2028Isup2.hkl

checkCIF report

Comment top

In continuation of our work on the lobeline analogues, and structure-affinity relationships of novel ligands for the vesicular monoamine transporter (Zheng et al., 2005), we have undertaken the design, synthesis and structural analysis of a series of phenyl substituted N-alkyl distyrylpyridine analogs. The primary reasons for the X-ray analysis of the title compound was to confirm the geometry of 2,6-distyryl groups and to obtain detailed information on the molecular structure. This information will be useful in structure-activity relationship (SAR) studies. The title compound was prepared by the reaction of N-methyl, 2,6-lutidine iodide with benzaldehyde in the presence of pyrrolidine in ethanol under microwave irradiation at 25-29 W power level and at 130 °C for 3 minutes (Biotage microwave initiator). The compound was recrystallized from ethanol. The molecular structure and the atom-numbering scheme are shown in Fig.1. The X-ray studies revealed that the 2,6-distyryl substituents in the title compound both have E geometry. The central pyridine ring makes a dihedral angle of 15.30 (10)° and 11.82 (11)° with the adjacent phenyl rings.

Related literature top

For conventional synthesis of the title compound?, see: Stanek et al. (1952). For the activity of related compounds, see Zheng et al. (2005).

Experimental top

A mixture of N-methyl, 2,6-lutidine iodide (0.249 g, 1.0 mmol), benzaldehyde (0.300 g, 2.5 mmol) and pyrrolidine (6 µl) in ethanol (2 ml) was placed in a microwave-ready pressure vial equipped with a stirbar and irradiated in a Biotage microwave initiator for 3 minutes with the temperature set at 130 °C, at a power range of 25-29 W at 5 bar pressure. The cooled reaction mixture was taken out of the initiator, diluted with ethyl acetate, and filtered to afford a crude yellow solid. Crystallization from alcohol produced a yellow crystalline product of N-methyl-2,6-(E)distyrylpyridinium iodide that was suitable for X-ray analysis. ¹H NMR (DMSO d₆): δ 4.28 (s, 3H), 7.47-7.49 (d, J=6 Hz, 4H), 7.62-7.27 (dd, J=30.3 Hz, J=15.9 Hz, 6H), 7.848-7.872 (d, J=7.2 Hz, 4H), 8.26-8.29 (m, 2H), 8.39-8.44 (t, J=7.8 Hz, 1H); ¹³C NMR (DMSO d₆): δ 41.97, 119.09, 124.02, 128.40, 128.91, 130.39, 134.87, 142.22, 143.11, 149.88, 153.10.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and local procedures.

Figures top

Fig. 1. A view of the molecule with the atom numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.

(E,E)-1-Methyl-2,6-distyrylpyridinium iodide top

Crystal data top

C₂₂H₂₀N⁺·I⁻	F(000) = 1696
M_r = 425.29	D_x = 1.577 Mg m⁻³
Monoclinic, C2/c	Cu Kα radiation, λ = 1.54178 Å
Hall symbol: -C 2yc	Cell parameters from 9883 reflections
a = 18.7309 (4) Å	θ = 4.4–68.5°
b = 9.5687 (2) Å	µ = 14.04 mm⁻¹
c = 19.9829 (4) Å	T = 90 K
β = 90.279 (1)°	Shard, yellow
V = 3581.50 (13) Å³	0.18 × 0.14 × 0.08 mm
Z = 8

Data collection top

Bruker X8 Proteum diffractometer	3303 independent reflections
Radiation source: fine-focus rotating anode	3286 reflections with I > 2σ(I)
Graded multilayer optics monochromator	R_int = 0.043
Detector resolution: 5.6 pixels mm^-1	θ_max = 68.5°, θ_min = 4.4°
ϕ and ω scans	h = −22→22
Absorption correction: multi-scan (SADABS in APEX2; Bruker, 2001)	k = −11→11
T_min = 0.211, T_max = 0.400	l = −24→24
24972 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.021	H-atom parameters constrained
wR(F²) = 0.055	w = 1/[σ²(F_o²) + (0.0309P)² + 5.1348P] where P = (F_o² + 2F_c²)/3
S = 1.09	(Δ/σ)_max = 0.003
3303 reflections	Δρ_max = 0.58 e Å⁻³
219 parameters	Δρ_min = −0.49 e Å⁻³
0 restraints	Extinction correction: SHELXTL (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.000067 (15)

Crystal data top

C₂₂H₂₀N⁺·I⁻	V = 3581.50 (13) Å³
M_r = 425.29	Z = 8
Monoclinic, C2/c	Cu Kα radiation
a = 18.7309 (4) Å	µ = 14.04 mm⁻¹
b = 9.5687 (2) Å	T = 90 K
c = 19.9829 (4) Å	0.18 × 0.14 × 0.08 mm
β = 90.279 (1)°

Data collection top

Bruker X8 Proteum diffractometer	3303 independent reflections
Absorption correction: multi-scan (SADABS in APEX2; Bruker, 2001)	3286 reflections with I > 2σ(I)
T_min = 0.211, T_max = 0.400	R_int = 0.043
24972 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.021	0 restraints
wR(F²) = 0.055	H-atom parameters constrained
S = 1.09	Δρ_max = 0.58 e Å⁻³
3303 reflections	Δρ_min = −0.49 e Å⁻³
219 parameters

Special details top

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.

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 > 2σ(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
I1	0.157566 (6)	0.613743 (12)	0.396017 (5)	0.01533 (8)
N1	0.38671 (8)	0.46130 (16)	0.46816 (7)	0.0115 (3)
C1	0.36127 (12)	0.60507 (19)	0.45527 (12)	0.0192 (5)
H1A	0.4014	0.6634	0.4410	0.029*
H1B	0.3407	0.6437	0.4963	0.029*
H1C	0.3248	0.6034	0.4199	0.029*
C2	0.44830 (10)	0.4136 (2)	0.43884 (9)	0.0133 (4)
C3	0.47346 (10)	0.2818 (2)	0.45649 (9)	0.0153 (4)
H3	0.5164	0.2477	0.4374	0.018*
C4	0.43651 (10)	0.2005 (2)	0.50154 (9)	0.0146 (4)
H4	0.4544	0.1112	0.5139	0.018*
C5	0.37368 (10)	0.24873 (19)	0.52856 (9)	0.0136 (4)
H5	0.3477	0.1915	0.5588	0.016*
C6	0.34807 (11)	0.37993 (18)	0.51204 (10)	0.0120 (4)
C7	0.28002 (10)	0.4316 (2)	0.53757 (9)	0.0133 (4)
H7	0.2554	0.5026	0.5135	0.016*
C8	0.25134 (11)	0.38157 (18)	0.59407 (10)	0.0146 (4)
H8	0.2794	0.3177	0.6194	0.018*
C9	0.18083 (10)	0.4165 (2)	0.62012 (9)	0.0139 (4)
C10	0.15174 (11)	0.3314 (2)	0.67007 (10)	0.0177 (4)
H10	0.1795	0.2576	0.6884	0.021*
C11	0.08281 (11)	0.3536 (2)	0.69312 (10)	0.0191 (4)
H11	0.0636	0.2945	0.7267	0.023*
C12	0.04199 (10)	0.4616 (2)	0.66730 (10)	0.0180 (4)
H12	−0.0055	0.4758	0.6823	0.022*
C13	0.07150 (11)	0.5492 (2)	0.61904 (9)	0.0169 (4)
H13	0.0442	0.6250	0.6021	0.020*
C14	0.13969 (10)	0.5276 (2)	0.59548 (9)	0.0154 (4)
H14	0.1588	0.5882	0.5625	0.018*
C15	0.48534 (11)	0.5004 (2)	0.38947 (10)	0.0189 (4)
H15	0.4637	0.5858	0.3760	0.023*
C16	0.54716 (11)	0.4660 (2)	0.36280 (10)	0.0183 (4)
H16	0.5664	0.3784	0.3761	0.022*
C17	0.58969 (10)	0.5469 (2)	0.31504 (9)	0.0150 (4)
C18	0.64612 (11)	0.4793 (2)	0.28280 (10)	0.0168 (4)
H18	0.6546	0.3828	0.2909	0.020*
C19	0.68995 (11)	0.5521 (2)	0.23897 (10)	0.0188 (4)
H19	0.7273	0.5047	0.2163	0.023*
C20	0.67921 (11)	0.6936 (2)	0.22840 (10)	0.0190 (4)
H20	0.7094	0.7435	0.1987	0.023*
C21	0.62407 (11)	0.7629 (2)	0.26133 (10)	0.0209 (4)
H21	0.6173	0.8603	0.2547	0.025*
C22	0.57920 (11)	0.6895 (2)	0.30369 (10)	0.0171 (4)
H22	0.5410	0.7366	0.3252	0.020*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
I1	0.01676 (10)	0.01507 (10)	0.01419 (10)	0.00358 (4)	0.00364 (6)	0.00323 (4)
N1	0.0131 (7)	0.0105 (7)	0.0109 (7)	0.0004 (6)	0.0008 (6)	−0.0004 (6)
C1	0.0188 (11)	0.0122 (10)	0.0267 (12)	0.0042 (7)	0.0086 (9)	0.0059 (7)
C2	0.0133 (9)	0.0154 (9)	0.0113 (9)	0.0005 (7)	0.0013 (7)	−0.0029 (7)
C3	0.0151 (9)	0.0161 (9)	0.0148 (9)	0.0033 (7)	0.0025 (7)	−0.0012 (7)
C4	0.0179 (9)	0.0114 (8)	0.0145 (9)	0.0010 (7)	−0.0013 (7)	−0.0004 (7)
C5	0.0169 (9)	0.0126 (9)	0.0112 (8)	−0.0013 (7)	0.0007 (7)	−0.0001 (7)
C6	0.0133 (10)	0.0146 (9)	0.0080 (9)	−0.0014 (6)	0.0005 (7)	−0.0011 (6)
C7	0.0144 (9)	0.0119 (9)	0.0134 (9)	0.0014 (7)	0.0010 (7)	−0.0005 (7)
C8	0.0148 (10)	0.0155 (10)	0.0136 (10)	0.0006 (7)	0.0004 (8)	0.0013 (6)
C9	0.0154 (9)	0.0166 (9)	0.0098 (9)	−0.0011 (8)	0.0006 (7)	−0.0006 (7)
C10	0.0181 (10)	0.0192 (10)	0.0156 (9)	0.0010 (8)	0.0013 (7)	0.0041 (8)
C11	0.0191 (10)	0.0238 (10)	0.0145 (9)	−0.0037 (9)	0.0046 (8)	0.0016 (8)
C12	0.0150 (9)	0.0234 (10)	0.0156 (9)	−0.0009 (8)	0.0028 (7)	−0.0048 (8)
C13	0.0195 (9)	0.0175 (9)	0.0137 (9)	0.0047 (8)	0.0009 (7)	−0.0020 (7)
C14	0.0200 (10)	0.0156 (9)	0.0106 (9)	−0.0003 (8)	0.0029 (7)	−0.0003 (7)
C15	0.0223 (10)	0.0150 (9)	0.0193 (10)	0.0041 (8)	0.0063 (8)	0.0037 (8)
C16	0.0204 (10)	0.0139 (9)	0.0208 (10)	0.0013 (8)	0.0062 (8)	0.0020 (8)
C17	0.0152 (9)	0.0181 (10)	0.0117 (9)	−0.0004 (8)	0.0008 (7)	−0.0001 (7)
C18	0.0194 (10)	0.0149 (9)	0.0161 (9)	0.0012 (8)	0.0036 (7)	−0.0002 (7)
C19	0.0190 (10)	0.0222 (10)	0.0154 (9)	−0.0005 (8)	0.0056 (8)	−0.0016 (8)
C20	0.0212 (10)	0.0224 (10)	0.0133 (9)	−0.0019 (8)	0.0042 (7)	0.0035 (8)
C21	0.0257 (11)	0.0187 (10)	0.0184 (10)	0.0025 (8)	0.0022 (8)	0.0049 (8)
C22	0.0177 (9)	0.0184 (10)	0.0151 (9)	0.0042 (8)	0.0031 (7)	0.0018 (7)

Geometric parameters (Å, º) top

N1—C2	1.374 (2)	C11—C12	1.384 (3)
N1—C6	1.380 (2)	C11—H11	0.9500
N1—C1	1.478 (2)	C12—C13	1.394 (3)
C1—H1A	0.9800	C12—H12	0.9500
C1—H1B	0.9800	C13—C14	1.379 (3)
C1—H1C	0.9800	C13—H13	0.9500
C2—C3	1.391 (3)	C14—H14	0.9500
C2—C15	1.467 (3)	C15—C16	1.319 (3)
C3—C4	1.379 (3)	C15—H15	0.9500
C3—H3	0.9500	C16—C17	1.467 (3)
C4—C5	1.377 (3)	C16—H16	0.9500
C4—H4	0.9500	C17—C22	1.397 (3)
C5—C6	1.383 (3)	C17—C18	1.399 (3)
C5—H5	0.9500	C18—C19	1.391 (3)
C6—C7	1.461 (3)	C18—H18	0.9500
C7—C8	1.341 (3)	C19—C20	1.385 (3)
C7—H7	0.9500	C19—H19	0.9500
C8—C9	1.461 (3)	C20—C21	1.395 (3)
C8—H8	0.9500	C20—H20	0.9500
C9—C10	1.401 (3)	C21—C22	1.387 (3)
C9—C14	1.401 (3)	C21—H21	0.9500
C10—C11	1.389 (3)	C22—H22	0.9500
C10—H10	0.9500

C2—N1—C6	121.83 (16)	C12—C11—C10	120.22 (19)
C2—N1—C1	120.35 (16)	C12—C11—H11	119.9
C6—N1—C1	117.78 (16)	C10—C11—H11	119.9
N1—C1—H1A	109.5	C11—C12—C13	119.12 (18)
N1—C1—H1B	109.5	C11—C12—H12	120.4
H1A—C1—H1B	109.5	C13—C12—H12	120.4
N1—C1—H1C	109.5	C14—C13—C12	121.16 (18)
H1A—C1—H1C	109.5	C14—C13—H13	119.4
H1B—C1—H1C	109.5	C12—C13—H13	119.4
N1—C2—C3	118.49 (17)	C13—C14—C9	120.16 (18)
N1—C2—C15	119.95 (17)	C13—C14—H14	119.9
C3—C2—C15	121.55 (17)	C9—C14—H14	119.9
C4—C3—C2	120.45 (18)	C16—C15—C2	123.32 (18)
C4—C3—H3	119.8	C16—C15—H15	118.3
C2—C3—H3	119.8	C2—C15—H15	118.3
C5—C4—C3	119.95 (18)	C15—C16—C17	127.73 (19)
C5—C4—H4	120.0	C15—C16—H16	116.1
C3—C4—H4	120.0	C17—C16—H16	116.1
C4—C5—C6	120.46 (17)	C22—C17—C18	118.89 (17)
C4—C5—H5	119.8	C22—C17—C16	122.98 (17)
C6—C5—H5	119.8	C18—C17—C16	118.00 (18)
N1—C6—C5	118.76 (17)	C19—C18—C17	120.53 (19)
N1—C6—C7	119.48 (16)	C19—C18—H18	119.7
C5—C6—C7	121.71 (17)	C17—C18—H18	119.7
C8—C7—C6	121.80 (18)	C20—C19—C18	120.00 (18)
C8—C7—H7	119.1	C20—C19—H19	120.0
C6—C7—H7	119.1	C18—C19—H19	120.0
C7—C8—C9	125.79 (18)	C19—C20—C21	120.00 (18)
C7—C8—H8	117.1	C19—C20—H20	120.0
C9—C8—H8	117.1	C21—C20—H20	120.0
C10—C9—C14	118.44 (18)	C22—C21—C20	119.98 (19)
C10—C9—C8	118.45 (18)	C22—C21—H21	120.0
C14—C9—C8	123.05 (17)	C20—C21—H21	120.0
C11—C10—C9	120.86 (19)	C21—C22—C17	120.56 (18)
C11—C10—H10	119.6	C21—C22—H22	119.7
C9—C10—H10	119.6	C17—C22—H22	119.7

C6—N1—C2—C3	−2.8 (3)	C8—C9—C10—C11	−175.20 (18)
C1—N1—C2—C3	174.87 (18)	C9—C10—C11—C12	−0.6 (3)
C6—N1—C2—C15	176.36 (17)	C10—C11—C12—C13	−1.3 (3)
C1—N1—C2—C15	−6.0 (3)	C11—C12—C13—C14	1.8 (3)
N1—C2—C3—C4	1.1 (3)	C12—C13—C14—C9	−0.2 (3)
C15—C2—C3—C4	−178.04 (18)	C10—C9—C14—C13	−1.7 (3)
C2—C3—C4—C5	1.0 (3)	C8—C9—C14—C13	175.49 (18)
C3—C4—C5—C6	−1.5 (3)	N1—C2—C15—C16	175.08 (19)
C2—N1—C6—C5	2.3 (3)	C3—C2—C15—C16	−5.8 (3)
C1—N1—C6—C5	−175.42 (18)	C2—C15—C16—C17	−177.77 (19)
C2—N1—C6—C7	−175.13 (17)	C15—C16—C17—C22	17.0 (3)
C1—N1—C6—C7	7.1 (3)	C15—C16—C17—C18	−167.2 (2)
C4—C5—C6—N1	−0.1 (3)	C22—C17—C18—C19	−1.5 (3)
C4—C5—C6—C7	177.27 (18)	C16—C17—C18—C19	−177.53 (18)
N1—C6—C7—C8	−158.92 (18)	C17—C18—C19—C20	1.9 (3)
C5—C6—C7—C8	23.7 (3)	C18—C19—C20—C21	−0.5 (3)
C6—C7—C8—C9	−173.77 (18)	C19—C20—C21—C22	−1.2 (3)
C7—C8—C9—C10	164.66 (19)	C20—C21—C22—C17	1.5 (3)
C7—C8—C9—C14	−12.5 (3)	C18—C17—C22—C21	−0.2 (3)
C14—C9—C10—C11	2.1 (3)	C16—C17—C22—C21	175.62 (19)

Experimental details

Crystal data
Chemical formula	C₂₂H₂₀N⁺·I⁻
M_r	425.29
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	90
a, b, c (Å)	18.7309 (4), 9.5687 (2), 19.9829 (4)
β (°)	90.279 (1)
V (Å³)	3581.50 (13)
Z	8
Radiation type	Cu Kα
µ (mm⁻¹)	14.04
Crystal size (mm)	0.18 × 0.14 × 0.08

Data collection
Diffractometer	Bruker X8 Proteum diffractometer
Absorption correction	Multi-scan (SADABS in APEX2; Bruker, 2001)
T_min, T_max	0.211, 0.400
No. of measured, independent and observed [I > 2σ(I)] reflections	24972, 3303, 3286
R_int	0.043
(sin θ/λ)_max (Å⁻¹)	0.604

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.021, 0.055, 1.09
No. of reflections	3303
No. of parameters	219
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.58, −0.49

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXTL (Sheldrick, 2008) and local procedures.

Acknowledgements

This investigation was supported by the NSF MRI grant CHE 0319176 (to SP). We thank Dr Greg Elliott for providing the microwave facilities.

References

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