5,7-Di-2-pyridyl-2,3-dihydro­thieno[3,4-b][1,4]dioxine

Djukic, B.; Harrington, L.E.; Britten, J.F.; Lemaire, M.T.

doi:10.1107/S1600536808001190

organic compounds

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ISSN: 2056-9890

Volume 64| Part 2| February 2008| Page o463

doi:10.1107/S1600536808001190

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5,7-Di-2-pyridyl-2,3-dihydrothieno[3,4-b][1,4]dioxine

Brandon Djukic,^a Laura E. Harrington,^b James F. Britten ^b and Martin T. Lemaire ^a ^*

^aDepartment of Chemistry, Brock University, 500 Glenridge Avenue, St Catharines, ON, Canada L2S 3A1, and ^bMcMaster University, Department of Chemistry, 1280 Main Street W., Hamilton, Ontario, Canada L8S 4M1
^*Correspondence e-mail: mlemaire@brocku.ca

(Received 7 January 2008; accepted 11 January 2008; online 16 January 2008)

The title compound, C₁₆H₁₂N₂O₂S, was prepared by a Neigishi cross-coupling reaction to investigate the coordination chemistry of thiophene-containing ligands. In the molecule, the pyridine rings are twisted from the thiophene ring by 20.6 (1) and 4.1 (2)°. The six-membered dihydrodioxine ring is in a half-chair conformation.

Related literature

For the structures of other 2,5-disubsituted 3,4-ethylenedioxythiophene (EDOT) derivatives, see: Lomas et al. (2007 ); and Sato et al. (2006 ). For related literature, see: Ghosh & Simonsen (1993 ); Han & Choi (2000 ); Roncali et al. (2005 ); Sotzing et al. (1996 ).

Experimental

Crystal data

C₁₆H₁₂N₂O₂S
M_r = 296.34
Monoclinic, P 2₁ /n
a = 10.5189 (12) Å
b = 9.8752 (12) Å
c = 13.1961 (18) Å
β = 97.752 (3)°
V = 1358.2 (3) Å³
Z = 4
Mo Kα radiation
μ = 0.24 mm⁻¹
T = 173 (2) K
0.38 × 0.30 × 0.20 mm

Data collection

Bruker APEXII diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.864, T_max = 1.000 (expected range = 0.823–0.952)
22945 measured reflections
5134 independent reflections
4316 reflections with I > 2σ(I)
R_int = 0.026

Refinement

R[F² > 2σ(F²)] = 0.037
wR(F²) = 0.108
S = 1.04
5134 reflections
238 parameters
All H-atom parameters refined
Δρ_max = 0.47 e Å⁻³
Δρ_min = −0.21 e Å⁻³

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

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808001190/lh2589sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808001190/lh2589Isup2.hkl

checkCIF report

Comment top

Derivatives of 3,4-ethylenedioxythiophene (EDOT) have been actively pursued primarily as precursors to polymers with interesting electronic and optical properties (Roncali et al., 2005). The presence of the ethylenedioxy substituent greatly enhances the stability of these materials relative to unsubstituted polythiophenes. As part of our efforts toward new molecule-based materials, we are investigating the propensity for 3,4-ethylenedioxythiophene derivatives to function as ligands for transition metal ions. We have prepared the title compound (I) featuring 2-pyridyl substituents appended to the 2,5-positions of the 3,4-ethylenedioxythiophene ring and are investigating the coordination chemistry of this potentially chelating ligand. We report herein the crystal structure of (I).

In the molecular structure of (I) bond lengths and angles within the EDOT moiety are within normal ranges (Han & Choi, 2000; Sotzing et al., 1996). As is typical in the structures of other EDOT derivatives, the six-membered dioxane-type ring in (I) is in a half-chair conformation, with the H atoms on the ethylene C atoms in a nearly gauche configuration. Each pyridine ring is tilted out of the plane of the EDOT moiety, with torsion angles of 19.39 (12) and -0.78 (12)° for S1—C11—C12—N2 and N1—C5—C6—S1, respectively and is likely the result of short intramolecular contacts between N and S atoms (2.923 (1) and 2.965 (1)Å for S1···N1 and S1···N2, respectively). Bond lengths between the EDOT group and the pyridine rings are 1.4626 (13) and 1.4609 (13) Å for C5—C6 and C11—C12, respectively. These lengths are the same (within experimental error) as those observed for the related bonds in the structure of 2-pyridylthiophene [1.469 (3) Å] (Ghosh & Simonsen, 1993).

Related literature top

For the structures of other 2,5-disubsituted 3,4-ethylenedioxythiophene (EDOT) derivatives, see: Lomas et al. (2007); and Sato et al. (2006).

For related literature, see: Ghosh & Simonsen (1993); Han & Choi (2000); Roncali et al. (2005); Sotzing et al. (1996).

Experimental top

2-pyridylzinc bromide solution (20.0 ml of a 0.5 M THF solution, 10.0 mmol) was added via syringe to a dry, nitrogen-purged Schlenk flask protected from light containing 2,5-dibromo-3,4-ethylenedioxythiophene (1.0 g, 3.3 mmol) and Pd(PPh₃)₄ (0.35 g, 0.3 mmol). The mixture was refluxed for 24 h, cooled to room temperature and stirred in basic edta solution (~0.2 M) for approximately 24 h. The edta solution was extracted with chloroform, concentrated to a small volume and poured into pentane to precipitate out the product as a pale yellow solid. Yield 0.48 g (49%). Crystals were grown by slow evaporation of an acetone solution of the product at 278 K. Anal.calcd (%) for C₁₆H₁₂N₂O₂S: C 64.85, H 4.09, N 9.46.Found: C 64.23, H 3.82, N 9.25. MS(EI+), m/z (%): 296 (100).

Computing details top

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

Figures top

Fig. 1. The molecular structure of the title compound with atom labels and 50% probability displacement ellipsoids for non-H atoms.

5,7-Di-2-pyridyl-2,3-dihydrothieno[3,4-b][1,4]dioxine top

Crystal data top

C₁₆H₁₂N₂O₂S	F(000) = 616
M_r = 296.34	D_x = 1.449 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 8327 reflections
a = 10.5189 (12) Å	θ = 2.6–32.3°
b = 9.8752 (12) Å	µ = 0.24 mm⁻¹
c = 13.1961 (18) Å	T = 173 K
β = 97.752 (3)°	Block, colourless
V = 1358.2 (3) Å³	0.38 × 0.30 × 0.20 mm
Z = 4

Data collection top

Bruker APEXII diffractometer	5134 independent reflections
Radiation source: fine-focus sealed tube	4316 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.026
ϕ and ω scans	θ_max = 33.3°, θ_min = 2.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −16→16
T_min = 0.864, T_max = 1.000	k = −8→15
22945 measured reflections	l = −20→18

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)] = 0.037	Hydrogen site location: difference Fourier map
wR(F²) = 0.109	All H-atom parameters refined
S = 1.05	w = 1/[σ²(F_o²) + (0.0623P)² + 0.2445P] where P = (F_o² + 2F_c²)/3
5134 reflections	(Δ/σ)_max = 0.001
238 parameters	Δρ_max = 0.47 e Å⁻³
0 restraints	Δρ_min = −0.21 e Å⁻³

Crystal data top

C₁₆H₁₂N₂O₂S	V = 1358.2 (3) Å³
M_r = 296.34	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 10.5189 (12) Å	µ = 0.24 mm⁻¹
b = 9.8752 (12) Å	T = 173 K
c = 13.1961 (18) Å	0.38 × 0.30 × 0.20 mm
β = 97.752 (3)°

Data collection top

Bruker APEXII diffractometer	5134 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	4316 reflections with I > 2σ(I)
T_min = 0.864, T_max = 1.000	R_int = 0.026
22945 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	0 restraints
wR(F²) = 0.109	All H-atom parameters refined
S = 1.05	Δρ_max = 0.47 e Å⁻³
5134 reflections	Δρ_min = −0.21 e Å⁻³
238 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
S1	0.52108 (2)	0.40887 (2)	0.128549 (18)	0.02244 (7)
O1	0.21374 (7)	0.28139 (9)	−0.04158 (6)	0.03008 (17)
N1	0.32131 (9)	0.54483 (9)	0.22458 (7)	0.02895 (18)
C1	0.24126 (12)	0.61030 (12)	0.27867 (9)	0.0343 (2)
H1	0.2820 (16)	0.6590 (17)	0.3407 (13)	0.046 (4)*
O2	0.44345 (8)	0.16437 (8)	−0.10327 (6)	0.02944 (16)
N2	0.76947 (9)	0.27018 (10)	0.12037 (8)	0.03112 (19)
C2	0.10899 (12)	0.60791 (12)	0.25650 (10)	0.0343 (2)
H2	0.0574 (15)	0.6560 (17)	0.2998 (12)	0.043 (4)*
C3	0.05533 (11)	0.53586 (12)	0.17120 (10)	0.0338 (2)
H3	−0.0338 (17)	0.5319 (17)	0.1520 (13)	0.044 (4)*
C4	0.13538 (11)	0.46837 (11)	0.11278 (9)	0.0294 (2)
H4	0.0956 (16)	0.4152 (16)	0.0528 (13)	0.043 (4)*
C5	0.26776 (9)	0.47352 (9)	0.14214 (7)	0.02228 (17)
C6	0.35800 (9)	0.39961 (9)	0.08746 (7)	0.02107 (17)
C7	0.33364 (9)	0.31265 (9)	0.00561 (7)	0.02180 (17)
C8	0.21613 (12)	0.21560 (15)	−0.13906 (9)	0.0373 (3)
H8B	0.1311 (17)	0.1762 (17)	−0.1607 (13)	0.045 (4)*
H8A	0.2400 (17)	0.2820 (17)	−0.1874 (14)	0.048 (4)*
C9	0.31708 (12)	0.10680 (12)	−0.13079 (10)	0.0343 (2)
H9B	0.3068 (16)	0.0402 (16)	−0.0763 (13)	0.042 (4)*
H9A	0.3192 (16)	0.0601 (16)	−0.1964 (13)	0.040 (4)*
C10	0.44657 (9)	0.25377 (9)	−0.02383 (7)	0.02233 (17)
C11	0.55669 (9)	0.29531 (9)	0.03618 (7)	0.02234 (17)
C12	0.68890 (10)	0.25174 (10)	0.03345 (8)	0.02406 (18)
C13	0.72798 (11)	0.19200 (11)	−0.05374 (9)	0.0289 (2)
H13	0.6694 (17)	0.1792 (18)	−0.1144 (13)	0.049 (5)*
C14	0.85394 (11)	0.14936 (13)	−0.04938 (10)	0.0341 (2)
H14	0.8846 (18)	0.1135 (18)	−0.1082 (14)	0.051 (5)*
C15	0.93616 (11)	0.16398 (14)	0.04084 (11)	0.0389 (3)
H15	1.0276 (17)	0.1367 (18)	0.0466 (13)	0.050 (5)*
C16	0.89017 (11)	0.22521 (14)	0.12321 (10)	0.0375 (3)
H16	0.9492 (17)	0.2418 (17)	0.1890 (14)	0.051 (5)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.02221 (12)	0.02250 (11)	0.02233 (12)	−0.00056 (7)	0.00197 (8)	0.00032 (7)
O1	0.0229 (3)	0.0409 (4)	0.0257 (3)	0.0009 (3)	0.0004 (3)	−0.0099 (3)
N1	0.0312 (4)	0.0294 (4)	0.0248 (4)	0.0052 (3)	−0.0010 (3)	−0.0057 (3)
C1	0.0382 (6)	0.0349 (5)	0.0283 (5)	0.0088 (4)	−0.0005 (4)	−0.0098 (4)
O2	0.0285 (4)	0.0329 (4)	0.0275 (4)	0.0003 (3)	0.0059 (3)	−0.0082 (3)
N2	0.0230 (4)	0.0383 (5)	0.0318 (5)	−0.0004 (3)	0.0027 (3)	−0.0059 (4)
C2	0.0367 (6)	0.0331 (5)	0.0335 (5)	0.0105 (4)	0.0055 (5)	−0.0073 (4)
C3	0.0270 (5)	0.0353 (5)	0.0388 (6)	0.0064 (4)	0.0036 (4)	−0.0084 (4)
C4	0.0257 (5)	0.0314 (5)	0.0305 (5)	0.0039 (4)	0.0020 (4)	−0.0075 (4)
C5	0.0258 (4)	0.0203 (4)	0.0207 (4)	0.0025 (3)	0.0028 (3)	0.0007 (3)
C6	0.0225 (4)	0.0212 (4)	0.0195 (4)	0.0012 (3)	0.0029 (3)	0.0017 (3)
C7	0.0216 (4)	0.0240 (4)	0.0197 (4)	0.0003 (3)	0.0022 (3)	0.0010 (3)
C8	0.0320 (6)	0.0513 (7)	0.0267 (5)	0.0050 (5)	−0.0027 (4)	−0.0137 (5)
C9	0.0323 (5)	0.0360 (5)	0.0343 (6)	−0.0025 (4)	0.0032 (4)	−0.0125 (4)
C10	0.0247 (4)	0.0224 (4)	0.0203 (4)	0.0011 (3)	0.0047 (3)	0.0009 (3)
C11	0.0224 (4)	0.0222 (4)	0.0229 (4)	0.0014 (3)	0.0051 (3)	0.0030 (3)
C12	0.0228 (4)	0.0237 (4)	0.0263 (4)	−0.0003 (3)	0.0058 (3)	0.0024 (3)
C13	0.0273 (5)	0.0318 (5)	0.0287 (5)	0.0001 (4)	0.0074 (4)	−0.0011 (4)
C14	0.0281 (5)	0.0376 (6)	0.0385 (6)	0.0003 (4)	0.0117 (4)	−0.0067 (4)
C15	0.0220 (5)	0.0447 (6)	0.0500 (7)	0.0011 (4)	0.0051 (5)	−0.0107 (5)
C16	0.0235 (5)	0.0471 (7)	0.0406 (6)	−0.0005 (4)	−0.0004 (4)	−0.0091 (5)

Geometric parameters (Å, º) top

S1—C6	1.7303 (10)	C5—C6	1.4626 (13)
S1—C11	1.7340 (10)	C6—C7	1.3767 (13)
O1—C7	1.3644 (12)	C7—C10	1.4229 (13)
O1—C8	1.4444 (13)	C8—C9	1.5042 (18)
N1—C1	1.3412 (14)	C8—H8B	0.982 (17)
N1—C5	1.3533 (13)	C8—H8A	0.971 (18)
C1—C2	1.3828 (18)	C9—H9B	0.991 (16)
C1—H1	0.996 (18)	C9—H9A	0.984 (16)
O2—C10	1.3674 (12)	C10—C11	1.3747 (14)
O2—C9	1.4463 (14)	C11—C12	1.4609 (13)
N2—C16	1.3408 (15)	C12—C13	1.4029 (14)
N2—C12	1.3435 (14)	C13—C14	1.3841 (16)
C2—C3	1.3857 (17)	C13—H13	0.950 (18)
C2—H2	0.965 (16)	C14—C15	1.3814 (19)
C3—C4	1.3867 (15)	C14—H14	0.948 (18)
C3—H3	0.938 (17)	C15—C16	1.3868 (18)
C4—C5	1.3950 (15)	C15—H15	0.992 (18)
C4—H4	0.994 (17)	C16—H16	1.010 (18)

C6—S1—C11	92.56 (5)	C9—C8—H8A	106.7 (10)
C7—O1—C8	112.47 (8)	H8B—C8—H8A	112.5 (15)
C1—N1—C5	117.10 (10)	O2—C9—C8	110.69 (10)
N1—C1—C2	124.42 (11)	O2—C9—H9B	105.4 (10)
N1—C1—H1	116.0 (9)	C8—C9—H9B	112.5 (10)
C2—C1—H1	119.5 (9)	O2—C9—H9A	106.0 (10)
C10—O2—C9	111.87 (8)	C8—C9—H9A	111.7 (9)
C16—N2—C12	117.70 (10)	H9B—C9—H9A	110.1 (13)
C1—C2—C3	117.94 (10)	O2—C10—C11	124.44 (9)
C1—C2—H2	119.8 (10)	O2—C10—C7	122.58 (9)
C3—C2—H2	122.3 (10)	C11—C10—C7	112.98 (8)
C2—C3—C4	119.15 (11)	C10—C11—C12	128.97 (9)
C2—C3—H3	121.6 (10)	C10—C11—S1	110.66 (7)
C4—C3—H3	119.3 (10)	C12—C11—S1	120.30 (7)
C3—C4—C5	119.10 (10)	N2—C12—C13	122.44 (10)
C3—C4—H4	118.4 (10)	N2—C12—C11	115.59 (9)
C5—C4—H4	122.5 (10)	C13—C12—C11	121.96 (9)
N1—C5—C4	122.27 (9)	C14—C13—C12	118.59 (11)
N1—C5—C6	115.39 (9)	C14—C13—H13	120.2 (10)
C4—C5—C6	122.32 (9)	C12—C13—H13	121.2 (10)
C7—C6—C5	129.33 (9)	C15—C14—C13	119.24 (11)
C7—C6—S1	110.53 (7)	C15—C14—H14	120.1 (12)
C5—C6—S1	120.07 (7)	C13—C14—H14	120.6 (12)
O1—C7—C6	124.20 (9)	C14—C15—C16	118.50 (11)
O1—C7—C10	122.50 (8)	C14—C15—H15	121.7 (10)
C6—C7—C10	113.28 (9)	C16—C15—H15	119.7 (10)
O1—C8—C9	110.71 (10)	N2—C16—C15	123.48 (12)
O1—C8—H8B	108.2 (10)	N2—C16—H16	116.1 (10)
C9—C8—H8B	110.2 (10)	C15—C16—H16	120.3 (10)
O1—C8—H8A	108.5 (10)

C5—N1—C1—C2	0.93 (18)	C9—O2—C10—C7	−17.88 (13)
N1—C1—C2—C3	−1.7 (2)	O1—C7—C10—O2	1.80 (14)
C1—C2—C3—C4	0.77 (19)	C6—C7—C10—O2	179.87 (8)
C2—C3—C4—C5	0.74 (18)	O1—C7—C10—C11	−177.64 (9)
C1—N1—C5—C4	0.72 (15)	C6—C7—C10—C11	0.44 (12)
C1—N1—C5—C6	−177.85 (9)	O2—C10—C11—C12	−3.24 (16)
C3—C4—C5—N1	−1.55 (16)	C7—C10—C11—C12	176.18 (9)
C3—C4—C5—C6	176.92 (10)	O2—C10—C11—S1	179.96 (7)
N1—C5—C6—C7	175.73 (10)	C7—C10—C11—S1	−0.62 (10)
C4—C5—C6—C7	−2.84 (16)	C6—S1—C11—C10	0.51 (7)
N1—C5—C6—S1	−0.78 (12)	C6—S1—C11—C12	−176.61 (8)
C4—C5—C6—S1	−179.35 (8)	C16—N2—C12—C13	−2.13 (16)
C11—S1—C6—C7	−0.26 (7)	C16—N2—C12—C11	176.57 (10)
C11—S1—C6—C5	176.86 (8)	C10—C11—C12—N2	−157.14 (10)
C8—O1—C7—C6	165.76 (10)	S1—C11—C12—N2	19.39 (12)
C8—O1—C7—C10	−16.38 (14)	C10—C11—C12—C13	21.56 (15)
C5—C6—C7—O1	1.22 (16)	S1—C11—C12—C13	−161.91 (8)
S1—C6—C7—O1	177.99 (8)	N2—C12—C13—C14	0.69 (16)
C5—C6—C7—C10	−176.82 (9)	C11—C12—C13—C14	−177.93 (10)
S1—C6—C7—C10	−0.04 (10)	C12—C13—C14—C15	1.45 (17)
C7—O1—C8—C9	45.42 (14)	C13—C14—C15—C16	−2.0 (2)
C10—O2—C9—C8	46.89 (13)	C12—N2—C16—C15	1.51 (19)
O1—C8—C9—O2	−62.83 (14)	C14—C15—C16—N2	0.6 (2)
C9—O2—C10—C11	161.49 (10)

Experimental details

Crystal data
Chemical formula	C₁₆H₁₂N₂O₂S
M_r	296.34
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	173
a, b, c (Å)	10.5189 (12), 9.8752 (12), 13.1961 (18)
β (°)	97.752 (3)
V (Å³)	1358.2 (3)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.24
Crystal size (mm)	0.38 × 0.30 × 0.20

Data collection
Diffractometer	Bruker APEXII diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.864, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	22945, 5134, 4316
R_int	0.026
(sin θ/λ)_max (Å⁻¹)	0.772

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.109, 1.05
No. of reflections	5134
No. of parameters	238
H-atom treatment	All H-atom parameters refined
Δρ_max, Δρ_min (e Å⁻³)	0.47, −0.21

Computer programs: APEX2 (Bruker, 2006), SHELXTL (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997).

Acknowledgements

The authors thank the Natural Sciences and Engineering Research Council of Canada for financial support. Martin Lemaire thanks Brock University for providing start-up funding for this research. X-ray crystallographic analyses were performed at the McMaster Analytical X-ray (MAX) Diffraction Facility.

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