A bi-TTF with a bipyridine spacer: 4,4′-bis­[(3,6,7-trimethyl­sulfanyltetra­thia­fulvalen-2-yl)sulfanylmeth­yl]-2,2′-bipyridine

Kaboub, L.; Fabre, J.-M.; Legros, J.-P.

doi:10.1107/S1600536808039111

organic compounds

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ISSN: 2056-9890

Volume 64| Part 12| December 2008| Pages o2484-o2485

doi:10.1107/S1600536808039111

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A bi-TTF with a bipyridine spacer: 4,4′-bis[(3,6,7-trimethylsulfanyltetrathiafulvalen-2-yl)sulfanylmethyl]-2,2′-bipyridine

Lakhemici Kaboub,^a Jean-Marc Fabre ^b and Jean-Pierre Legros ^c,^d ^*

^aLaboratoire de Chimie des Matériaux Organiques, Centre Universitaire de Tébessa, Route de Constantine, 12000 Tébessa, Algeria, ^bInstitut Charles Gerhardt, UMR CNRS 5253, AM2N, ENSCM, 8 rue de l'Ecole Normale, F-34296 Montpellier cedex 5, France, ^cCNRS; LCC (Laboratoire de Chimie de Coordination), 205 route de Narbonne, F-31077 Toulouse, France, and ^dUniversité de Toulouse; UPS,INPT; LCC, F-31077 Toulouse, France
^*Correspondence e-mail: jean-pierre.legros@lcc-toulouse.fr

(Received 17 November 2008; accepted 21 November 2008; online 29 November 2008)

The title compound, C₃₀H₂₈N₂S₁₆, is a precursor to hybrid magnetic materials. The complete molecule is generated by a crystallographic inversion centre. In the crystal structure, the TTF core is not planar and adopts a chair conformation; the two C₃S₂ rings are folded around the S⋯S hinges, the dihedral angles being 17.14 (8) and 13.46 (7)°. There is a short S⋯S contact [3.4863 (14) Å] in the crystal structure.

Related literature

For general background, see: Yagubskii (1993 ); Williams et al. (1992 ); Sakata et al. (1998 ); Fabre (2002 ). For coordination complexes of TTF with nitrogen aromatic substituents, see: Setifi et al. (2003 ); Liu et al. (2003 ); Boudiba et al. (2005 ). For the double Wittig coupling reaction used in the synthesis of the bi-TTF(bipyridine), see: Ikeda et al. (1993 ); Gonzales et al. (2000 ). For the synthesis of the precursors, see: Doria et al. (1986 ); Hudhomme et al. (2006 ); Blanchard et al. (1993 ).

Experimental

Crystal data

C₃₀H₂₈N₂S₁₆
M_r = 929.50
Triclinic, $[P \overline 1]$
a = 7.4840 (12) Å
b = 7.7691 (11) Å
c = 17.707 (3) Å
α = 88.973 (12)°
β = 80.071 (13)°
γ = 72.245 (13)°
V = 965.2 (3) Å³
Z = 1
Mo Kα radiation
μ = 0.92 mm⁻¹
T = 293 (2) K
0.19 × 0.11 × 0.06 mm

Data collection

Oxford Diffraction XCalibur diffractometer with CCD detector
Absorption correction: multi-scan (Blessing, 1995 ) T_min = 0.884, T_max = 0.937
6690 measured reflections
3391 independent reflections
1942 reflections with I > 2σ(I)
R_int = 0.038

Refinement

R[F² > 2σ(F²)] = 0.035
wR(F²) = 0.070
S = 0.83
3391 reflections
220 parameters
H-atom parameters constrained
Δρ_max = 0.23 e Å⁻³
Δρ_min = −0.21 e Å⁻³

Data collection: CrysAlis CCD (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]$ ); cell refinement: CrysAlis RED (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]$ ); data reduction: CrysAlis RED; program(s) used to solve structure: SIR92 (Altomare et al., 1993 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEPIII (Burnett & Johnson, 1996 ), CAMERON (Watkin et al., 1993 ) and ORTEP-3 (Farrugia, 1997 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808039111/nc2124sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808039111/nc2124Isup2.hkl

checkCIF report

Comment top

To date the search for solids presenting two physical properties such as magnetism and electrical conductivity inside a same material has expanded greatly, particularly with materials involving tetrathiafulvalene (TTF) derivatives well known to provide conducting and even superconducting salts (Williams et al., 1992; Yagubskii,1993; Sakata et al., 1998: Fabre, 2002). To introduce a magnetic network, involving localized spins, inside such conducting salts, a particularly promising way is to build a coordination complex between a transition metal (Cu, Co ···) and a pyridine or bipyridine moiety bonded to a TTF core (Setifi et al., 2003; Liu et al., 2003; Boudiba et al., 2005). Following this strategy we synthesized the title precursor: bi-TTF(bipyridine) 1 and studied its crystal structure to verify if the molecular geometry could allow a subsequent easy formation of the target coordinating complex. The molecular structure is shown in Fig. 1. A s expected two TTF cores bearing methylsulfanyl substituents are connected by a bipyridine spacer. The molecule lies on a crystallographic centre of symmetry located at the centre of the bipyridine moiety, the asymmetric unit is thus composed of half a molecule. As a result the bipyridine spacer is in the trans conformation. The TTF cores deviate strongly from planarity and take a chair conformation. The two C₃S₂ rings are folded around the S···S hinges: the central group S3/S4/C5/C6/S5/S6 is planar and the external planes S3/S4/C3/C4 and S5/S6/C7/C8 make dihedral angles of 17.14 (8)° and 13.46 (7)° respectively. There is a short S&ctdot;S contact [3.4863 (14) Å] in the crystal structure.

Related literature top

For general background, see: Yagubskii (1993); Williams et al. (1992); Sakata et al. (1998); Fabre (2002). For coordination complexes of TTF with nitrogen aromatic substituents, see: Setifi et al. (2003); Liu et al. (2003); Boudiba et al. (2005). For the double Wittig coupling reaction used in the synthesis of the bi-TTF(bipyridine), see: Ikeda et al. (1993); Gonzales et al. (2000). For the synthesis of the precursors, see Doria et al. (1986); Hudhomme et al. (2006); Blanchard et al. (1993).

Experimental top

The bi-TTF(bipyridine) 1 was synthesized (37% yield) by using a double Wittig coupling reaction (Ikeda, 1993; Gonzalez, 2000) between two appropriate formyl-TTF units and 4,4'-bis(methyltripenylphosphonium)-2,2'-bipyridinedibromide previously obtained as described in the literature (Doria, 1986). Red crystals (m.p.: 158°C) of 1 were obtained as thin platelets by slow evaporation of a solution of 1 in a mixture of dichloromethane-acetonitrile.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis RED (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996), CAMERON (Watkin et al., 1993) and ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

Fig. 1. The molecular structure of the title compound, with atom labels and 50% probability displacement ellipsoids for non-H atoms. Symmetry code: i = -x+1, -y+1, -z+1.

4,4'-bis[(3,6,7-trimethylsulfanyltetrathiafulvalen-2-yl)sulfanylmethyl]- 2,2'-bipyridine top

Crystal data top

C₃₀H₂₈N₂S₁₆	Z = 1
M_r = 929.50	F(000) = 478
Triclinic, P1	D_x = 1.599 Mg m⁻³
Hall symbol: -P 1	Melting point: 431 K
a = 7.4840 (12) Å	Mo Kα radiation, λ = 0.71073 Å
b = 7.7691 (11) Å	Cell parameters from 1223 reflections
c = 17.707 (3) Å	θ = 2.9–25.0°
α = 88.973 (12)°	µ = 0.92 mm⁻¹
β = 80.071 (13)°	T = 293 K
γ = 72.245 (13)°	Block, red
V = 965.2 (3) Å³	0.19 × 0.11 × 0.06 mm

Data collection top

Oxford Diffraction XCalibur diffractometer with CCD detector	3391 independent reflections
Radiation source: fine-focus sealed tube	1942 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.039
ϕ and ω scans	θ_max = 25.0°, θ_min = 2.9°
Absorption correction: multi-scan (Blessing, 1995)	h = −8→8
T_min = 0.884, T_max = 0.937	k = −9→9
6690 measured reflections	l = −18→21

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)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.071	H-atom parameters constrained
S = 0.83	w = 1/[σ²(F_o²) + (0.0277P)²] where P = (F_o² + 2F_c²)/3
3391 reflections	(Δ/σ)_max = 0.013
220 parameters	Δρ_max = 0.23 e Å⁻³
0 restraints	Δρ_min = −0.22 e Å⁻³

Crystal data top

C₃₀H₂₈N₂S₁₆	γ = 72.245 (13)°
M_r = 929.50	V = 965.2 (3) Å³
Triclinic, P1	Z = 1
a = 7.4840 (12) Å	Mo Kα radiation
b = 7.7691 (11) Å	µ = 0.92 mm⁻¹
c = 17.707 (3) Å	T = 293 K
α = 88.973 (12)°	0.19 × 0.11 × 0.06 mm
β = 80.071 (13)°

Data collection top

Oxford Diffraction XCalibur diffractometer with CCD detector	3391 independent reflections
Absorption correction: multi-scan (Blessing, 1995)	1942 reflections with I > 2σ(I)
T_min = 0.884, T_max = 0.937	R_int = 0.039
6690 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.035	0 restraints
wR(F²) = 0.071	H-atom parameters constrained
S = 0.83	Δρ_max = 0.23 e Å⁻³
3391 reflections	Δρ_min = −0.22 e Å⁻³
220 parameters

Special details top

Experimental. Excalibur (Oxford Diffraction) four-circle Kappa geometry diffractometer equipped with an area CCD detector. Crystal-detector distance (mm): 70.0

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
C1	−0.3976 (5)	0.7011 (5)	0.9533 (2)	0.0573 (11)
H1A	−0.3692	0.6081	0.9142	0.069*
H1B	−0.5251	0.7212	0.9806	0.069*
H1C	−0.3095	0.6642	0.9884	0.069*
C2	0.0146 (6)	1.2151 (5)	0.9481 (2)	0.0681 (13)
H2A	−0.0135	1.1531	0.9938	0.082*
H2B	−0.0070	1.3402	0.9609	0.082*
H2C	0.1455	1.1612	0.9247	0.082*
C3	−0.1411 (4)	0.8506 (4)	0.86485 (17)	0.0307 (8)
C4	−0.0438 (4)	0.9702 (4)	0.85327 (17)	0.0300 (8)
C5	0.1986 (4)	0.6686 (4)	0.79718 (18)	0.0339 (8)
C6	0.3591 (4)	0.5317 (4)	0.77605 (17)	0.0325 (8)
C7	0.6075 (4)	0.2257 (4)	0.72586 (16)	0.0271 (8)
C8	0.7017 (4)	0.3475 (4)	0.71193 (17)	0.0277 (8)
C9	0.5564 (5)	−0.0019 (4)	0.62192 (17)	0.0366 (8)
H9A	0.5827	−0.1235	0.6028	0.044*
H9B	0.4232	0.0432	0.6433	0.044*
C10	0.9345 (5)	0.4866 (5)	0.6095 (2)	0.0711 (13)
H10A	0.8469	0.4962	0.5748	0.085*
H10B	1.0597	0.4718	0.5809	0.085*
H10C	0.8944	0.5944	0.6417	0.085*
C11	0.6020 (4)	0.1130 (4)	0.55723 (17)	0.0296 (8)
C12	0.5025 (4)	0.2947 (4)	0.55804 (17)	0.0308 (8)
H12	0.4020	0.3454	0.5979	0.037*
C13	0.5516 (4)	0.4015 (4)	0.49995 (17)	0.0276 (8)
C14	0.7883 (5)	0.1602 (4)	0.44029 (19)	0.0381 (9)
H14	0.8869	0.1118	0.3995	0.046*
C15	0.7491 (4)	0.0458 (4)	0.49646 (17)	0.0351 (8)
H15	0.8209	−0.0757	0.4935	0.042*
N1	0.6944 (4)	0.3353 (3)	0.44078 (14)	0.0343 (7)
S1	−0.37725 (13)	0.90564 (13)	0.91017 (6)	0.0500 (3)
S2	−0.13591 (13)	1.19803 (12)	0.88259 (5)	0.0442 (3)
S3	−0.02471 (12)	0.63191 (11)	0.82438 (5)	0.0408 (2)
S4	0.18635 (13)	0.89647 (12)	0.79792 (5)	0.0451 (3)
S5	0.37241 (12)	0.30319 (11)	0.77697 (5)	0.0419 (3)
S6	0.58066 (12)	0.56994 (11)	0.74683 (5)	0.0409 (3)
S7	0.69659 (12)	−0.00222 (11)	0.69692 (5)	0.0333 (2)
S8	0.93880 (12)	0.29726 (12)	0.66720 (5)	0.0453 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.051 (2)	0.054 (3)	0.064 (3)	−0.026 (2)	0.017 (2)	−0.008 (2)
C2	0.108 (4)	0.050 (3)	0.059 (3)	−0.032 (3)	−0.034 (3)	0.001 (2)
C3	0.0287 (19)	0.033 (2)	0.0275 (19)	−0.0055 (15)	−0.0035 (15)	0.0019 (15)
C4	0.0294 (19)	0.0278 (19)	0.0287 (19)	−0.0028 (15)	−0.0052 (15)	−0.0004 (15)
C5	0.0280 (19)	0.0282 (19)	0.045 (2)	−0.0107 (16)	−0.0004 (16)	0.0009 (16)
C6	0.0274 (19)	0.0291 (19)	0.038 (2)	−0.0093 (16)	0.0030 (16)	−0.0033 (16)
C7	0.0237 (18)	0.0235 (19)	0.0299 (19)	−0.0010 (14)	−0.0044 (15)	−0.0019 (14)
C8	0.0224 (18)	0.0268 (19)	0.0293 (18)	−0.0038 (15)	0.0014 (15)	−0.0034 (15)
C9	0.042 (2)	0.031 (2)	0.041 (2)	−0.0131 (16)	−0.0135 (18)	0.0027 (16)
C10	0.046 (3)	0.083 (3)	0.079 (3)	−0.027 (2)	0.011 (2)	0.025 (3)
C11	0.0317 (19)	0.0278 (19)	0.033 (2)	−0.0109 (15)	−0.0132 (16)	0.0020 (15)
C12	0.0281 (18)	0.033 (2)	0.0307 (19)	−0.0090 (15)	−0.0052 (15)	0.0016 (15)
C13	0.0264 (18)	0.0279 (18)	0.0290 (18)	−0.0063 (14)	−0.0098 (15)	0.0016 (15)
C14	0.031 (2)	0.038 (2)	0.041 (2)	−0.0062 (17)	−0.0012 (17)	−0.0046 (17)
C15	0.036 (2)	0.0276 (19)	0.040 (2)	−0.0027 (16)	−0.0142 (18)	−0.0004 (17)
N1	0.0322 (16)	0.0298 (17)	0.0366 (17)	−0.0053 (13)	−0.0019 (14)	0.0005 (13)
S1	0.0310 (5)	0.0449 (6)	0.0615 (7)	−0.0045 (4)	0.0131 (5)	−0.0036 (5)
S2	0.0453 (6)	0.0301 (5)	0.0517 (6)	−0.0035 (4)	−0.0073 (5)	−0.0098 (4)
S3	0.0268 (5)	0.0278 (5)	0.0627 (6)	−0.0086 (4)	0.0076 (5)	−0.0077 (4)
S4	0.0335 (5)	0.0282 (5)	0.0667 (7)	−0.0098 (4)	0.0105 (5)	−0.0042 (5)
S5	0.0310 (5)	0.0280 (5)	0.0620 (7)	−0.0109 (4)	0.0086 (5)	−0.0017 (4)
S6	0.0281 (5)	0.0266 (5)	0.0636 (7)	−0.0094 (4)	0.0061 (5)	−0.0077 (4)
S7	0.0382 (5)	0.0230 (5)	0.0360 (5)	−0.0030 (4)	−0.0107 (4)	0.0023 (4)
S8	0.0246 (5)	0.0390 (5)	0.0627 (7)	−0.0041 (4)	0.0075 (5)	−0.0003 (5)

Geometric parameters (Å, º) top

C1—S1	1.788 (3)	C8—S8	1.741 (3)
C1—H1A	0.9599	C8—S6	1.755 (3)
C1—H1B	0.9599	C9—C11	1.497 (4)
C1—H1C	0.9599	C9—S7	1.828 (3)
C2—S2	1.783 (4)	C9—H9A	0.9600
C2—H2A	0.9599	C9—H9B	0.9600
C2—H2B	0.9599	C10—S8	1.771 (3)
C2—H2C	0.9599	C10—H10A	0.9599
C3—C4	1.338 (4)	C10—H10B	0.9599
C3—S1	1.736 (3)	C10—H10C	0.9599
C3—S3	1.756 (3)	C11—C12	1.380 (4)
C4—S2	1.744 (3)	C11—C15	1.380 (4)
C4—S4	1.758 (3)	C12—C13	1.381 (4)
C5—C6	1.340 (4)	C12—H12	0.9300
C5—S4	1.744 (3)	C13—N1	1.342 (4)
C5—S3	1.765 (3)	C13—C13ⁱ	1.489 (6)
C6—S5	1.747 (3)	C14—N1	1.327 (4)
C6—S6	1.762 (3)	C14—C15	1.376 (4)
C7—C8	1.339 (4)	C14—H14	0.9300
C7—S7	1.743 (3)	C15—H15	0.9300
C7—S5	1.761 (3)

S1—C1—H1A	109.5	C11—C9—H9B	109.4
S1—C1—H1B	109.5	S7—C9—H9B	109.4
H1A—C1—H1B	109.5	H9A—C9—H9B	108.0
S1—C1—H1C	109.5	S8—C10—H10A	109.5
H1A—C1—H1C	109.5	S8—C10—H10B	109.5
H1B—C1—H1C	109.5	H10A—C10—H10B	109.5
S2—C2—H2A	109.5	S8—C10—H10C	109.5
S2—C2—H2B	109.5	H10A—C10—H10C	109.5
H2A—C2—H2B	109.5	H10B—C10—H10C	109.5
S2—C2—H2C	109.5	C12—C11—C15	117.1 (3)
H2A—C2—H2C	109.5	C12—C11—C9	120.7 (3)
H2B—C2—H2C	109.5	C15—C11—C9	122.2 (3)
C4—C3—S1	123.6 (2)	C11—C12—C13	120.3 (3)
C4—C3—S3	116.7 (2)	C11—C12—H12	119.9
S1—C3—S3	119.55 (18)	C13—C12—H12	119.9
C3—C4—S2	124.6 (2)	N1—C13—C12	122.5 (3)
C3—C4—S4	117.5 (2)	N1—C13—C13ⁱ	116.2 (3)
S2—C4—S4	117.70 (18)	C12—C13—C13ⁱ	121.3 (4)
C6—C5—S4	124.5 (2)	N1—C14—C15	124.1 (3)
C6—C5—S3	121.8 (2)	N1—C14—H14	118.0
S4—C5—S3	113.67 (18)	C15—C14—H14	118.0
C5—C6—S5	124.6 (2)	C14—C15—C11	119.3 (3)
C5—C6—S6	121.5 (2)	C14—C15—H15	120.3
S5—C6—S6	113.88 (18)	C11—C15—H15	120.3
C8—C7—S7	125.6 (2)	C14—N1—C13	116.8 (3)
C8—C7—S5	117.1 (2)	C3—S1—C1	104.34 (16)
S7—C7—S5	117.26 (17)	C4—S2—C2	101.90 (17)
C7—C8—S8	124.6 (2)	C3—S3—C5	94.78 (15)
C7—C8—S6	117.1 (2)	C5—S4—C4	94.69 (15)
S8—C8—S6	118.20 (17)	C6—S5—C7	95.17 (14)
C11—C9—S7	111.1 (2)	C8—S6—C6	95.04 (15)
C11—C9—H9A	109.4	C7—S7—C9	99.50 (14)
S7—C9—H9A	109.4	C8—S8—C10	102.28 (16)

Symmetry code: (i) −x+1, −y+1, −z+1.

Experimental details

Crystal data
Chemical formula	C₃₀H₂₈N₂S₁₆
M_r	929.50
Crystal system, space group	Triclinic, P1
Temperature (K)	293
a, b, c (Å)	7.4840 (12), 7.7691 (11), 17.707 (3)
α, β, γ (°)	88.973 (12), 80.071 (13), 72.245 (13)
V (Å³)	965.2 (3)
Z	1
Radiation type	Mo Kα
µ (mm⁻¹)	0.92
Crystal size (mm)	0.19 × 0.11 × 0.06

Data collection
Diffractometer	Oxford Diffraction XCalibur diffractometer with CCD detector
Absorption correction	Multi-scan (Blessing, 1995)
T_min, T_max	0.884, 0.937
No. of measured, independent and observed [I > 2σ(I)] reflections	6690, 3391, 1942
R_int	0.039
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.035, 0.071, 0.83
No. of reflections	3391
No. of parameters	220
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.23, −0.22

Computer programs: CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), SIR92 (Altomare et al., 1993), SHELXL97 (Sheldrick, 2008), ORTEPIII (Burnett & Johnson, 1996), CAMERON (Watkin et al., 1993) and ORTEP-3 (Farrugia, 1997), WinGX (Farrugia, 1999).

Acknowledgements

The authors are grateful to Dr Laure Vendier for collecting the data. This work was in part achieved in the framework of a Franco-Algerian Cooperation Programme (PROFAS); we warmly thank the participating organizations.

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