1,4-Bis(2-mercaptobenzo­thia­zolyl)­butane

The molecular structure of the title compound, C₁₈H₁₆N₂S₄, has a center of symmetry. All the C and S atoms in the central alkyl chain are coplanar, and this plane is almost perpendic­ular to the benzo­thia­zolyl rings. The mol­ecules are linked together by intermolecular S...S interactions to form a one-dimensional chain.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.042
• wR factor = 0.081
• Data-to-parameter ratio = 14.3

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level C:



ABSTM_02  Alert C The ratio of Tmax/Tmin expected RT(exp) is > 1.10
          Absorption corrections should be applied.
          Tmin and Tmax expected:      0.877     0.969
          RT(exp) =      1.105

REFLT_03
         From the CIF: _diffrn_reflns_theta_max           28.29
         From the CIF: _reflns_number_total               2020
         TEST2: Reflns within _diffrn_reflns_theta_max
         Count of symmetry unique reflns         2163
         Completeness (_total/calc)             93.39%
          Alert C: < 95% complete


 0 Alert Level A = Potentially serious problem

 0 Alert Level B = Potential problem

 2 Alert Level C = Please check

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S1. Comment

One of reasons for the recent intensive interest in design flexible multidentate ligand is to develop a new family of microporous, helicate materials, and other coordination polymers with unusual porous structures (Cai et al., 2001; Albada et al., 2000; Zhang et al., 2002). Moreover, the flexiblity and conformational freedom of such ligands offer the possibility of generating unique frameworks with useful properties (Bu et al., 2001; Hou et al., 2002). As part of our systematic investigation of the coordination chemistry of flexible ligand, we report here the synthesis and crystal structure of the title compound, (I).

The title molecule has a center of symmetry at the mid-point of the central C—C bond (Fig. 1). The C1—C2 and C1—C1ⁱ bond lengths are all close to the standard value for a single-bond length (see Table 1). All the C and S atoms between the two benzothiazolyl rings are coplanar; this plane is almost perpendicular to the planes of the benzothiazolyl rings, which are parallel to each other. The S—C bond distances are in the range 1.727 (2)–1.809 (3) Å, which are similar to those of S—C bonds of the analogous compound 1,5-bis(benzothiazolyl)-3-thiapentane (Grapperhaus et al., 2002), the C atom in the longest C—S bond belonging to the methylene group. The molecules are linked together by an intermolecular S2···S2(-x, −y, 1 − z) interaction of 3.485 (2) Å to form a one-dimensional chain.

S2. Experimental

The title compound, (I), was prepared from 2-mercaptobenzothiazole and 1,4-dibromobutane in 56% yield, using the similar reaction reported by Chen et al. (2003). Crystals of (I) suitable for X-ray analysis were grown from a chloroform solution. Calculated (%) for C₁₈H₁₆N₂S₄: C 55.64, H 4.15, N 7.21; found (%): C 55.48, H 4.10, N 7.18.

S3. Refinement

All H atoms were located from difference syntheses and refined isotropically. The C—H distances are in the range 0.89 (2)–0.98 (2) Å.

Computing details

Data collection: SMART (Bruker, 1998); cell refinement: SMART; data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1998); software used to prepare material for publication: SHELXTL.

Figures

Fig. 1. A View of the molecular structure of (I). Displacement ellipsoids are drawn at the 50% probability level.

(I)

Crystal data

C18H16N2S4	F(000) = 404
Mr = 388.57	Dx = 1.49 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 10.9072 (18) Å	Cell parameters from 887 reflections
b = 4.9003 (8) Å	θ = 5.5–46.2°
c = 16.767 (3) Å	µ = 0.55 mm^−1
β = 104.868 (3)°	T = 293 K
V = 866.2 (2) Å^3	Block, colourless
Z = 2	0.25 × 0.20 × 0.06 mm

Data collection

Bruker SMART diffractometer	Rint = 0.050
ϕ and ω scans	θmax = 28.3°, θmin = 1.9°
5025 measured reflections	h = −14→14
2020 independent reflections	k = −6→6
1248 reflections with I > 2σ(I)	l = −17→22

Refinement

Refinement on F^2	0 restraints
Least-squares matrix: full	All H-atom parameters refined
R[F^2 > 2σ(F^2)] = 0.042	w = 1/[σ^2(Fo^2) + (0.0257P)^2] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.081	(Δ/σ)max = 0.001
S = 0.84	Δρmax = 0.34 e Å^−3
2020 reflections	Δρmin = −0.25 e Å^−3
141 parameters

Special details

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
S1	0.18452 (6)	0.44087 (13)	0.50542 (4)	0.0512 (2)
S2	0.06435 (6)	0.06905 (13)	0.60430 (4)	0.0454 (2)
N	0.30799 (18)	0.1533 (3)	0.64017 (11)	0.0377 (5)
C2	0.3415 (3)	0.5880 (5)	0.52488 (19)	0.0483 (7)
C1	0.4362 (2)	0.4279 (5)	0.49193 (18)	0.0422 (6)
C3	0.2027 (2)	0.2190 (4)	0.58924 (14)	0.0371 (6)
C4	0.2856 (2)	−0.0360 (4)	0.69731 (14)	0.0343 (5)
C5	0.3778 (3)	−0.1570 (5)	0.75961 (15)	0.0425 (6)
C6	0.3417 (3)	−0.3499 (5)	0.80885 (16)	0.0486 (7)
C7	0.2159 (3)	−0.4198 (5)	0.79782 (17)	0.0510 (7)
C8	0.1227 (3)	−0.3018 (5)	0.73710 (16)	0.0462 (7)
C9	0.1582 (2)	−0.1086 (4)	0.68654 (13)	0.0351 (5)
H1	0.462 (2)	−0.111 (4)	0.7654 (13)	0.043 (7)*
H2	0.405 (2)	−0.434 (4)	0.8495 (14)	0.047 (7)*
H3	0.198 (2)	−0.546 (4)	0.8316 (14)	0.050 (7)*
H4	0.0397 (19)	−0.353 (4)	0.7272 (12)	0.033 (6)*
H5	0.374 (2)	0.621 (4)	0.5844 (14)	0.052 (7)*
H6	0.325 (2)	0.756 (5)	0.4976 (14)	0.062 (8)*
H7	0.4468 (18)	0.250 (4)	0.5191 (12)	0.038 (6)*
H8	0.402 (2)	0.398 (4)	0.4328 (14)	0.042 (6)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0495 (4)	0.0549 (4)	0.0510 (4)	0.0046 (3)	0.0164 (3)	0.0151 (4)
S2	0.0337 (4)	0.0553 (4)	0.0472 (4)	−0.0005 (3)	0.0105 (3)	0.0071 (3)
N	0.0353 (12)	0.0392 (11)	0.0401 (12)	−0.0015 (9)	0.0121 (10)	0.0001 (10)
C2	0.0632 (19)	0.0383 (15)	0.0494 (18)	−0.0044 (14)	0.0256 (15)	−0.0014 (15)
C1	0.0548 (18)	0.0344 (14)	0.0427 (16)	−0.0051 (12)	0.0217 (14)	−0.0024 (13)
C3	0.0397 (15)	0.0367 (13)	0.0379 (13)	0.0015 (11)	0.0155 (12)	−0.0012 (11)
C4	0.0367 (14)	0.0330 (12)	0.0347 (13)	−0.0002 (11)	0.0117 (11)	−0.0049 (11)
C5	0.0360 (16)	0.0464 (15)	0.0441 (15)	0.0017 (13)	0.0082 (13)	0.0007 (13)
C6	0.0513 (19)	0.0510 (16)	0.0414 (16)	0.0081 (14)	0.0079 (14)	0.0051 (14)
C7	0.062 (2)	0.0468 (16)	0.0496 (17)	0.0026 (15)	0.0244 (16)	0.0107 (14)
C8	0.0401 (17)	0.0488 (16)	0.0538 (17)	−0.0035 (14)	0.0197 (15)	0.0048 (14)
C9	0.0343 (14)	0.0377 (13)	0.0353 (13)	0.0001 (11)	0.0125 (11)	−0.0021 (11)

Geometric parameters (Å, º)

S1—C3	1.747 (2)	C1—H8	0.98 (2)
S1—C2	1.809 (3)	C4—C5	1.384 (3)
S2—C9	1.727 (2)	C4—C9	1.399 (3)
S2—C3	1.754 (2)	C5—C6	1.377 (3)
N—C3	1.284 (3)	C5—H1	0.93 (2)
N—C4	1.400 (3)	C6—C7	1.380 (4)
C2—C1	1.510 (3)	C6—H2	0.93 (2)
C2—H5	0.98 (2)	C7—C8	1.369 (3)
C2—H6	0.94 (2)	C7—H3	0.89 (2)
C1—C1^i	1.522 (5)	C8—C9	1.390 (3)
C1—H7	0.976 (19)	C8—H4	0.913 (19)
C3—S1—C2	101.31 (13)	C5—C4—C9	119.6 (2)
C9—S2—C3	88.30 (11)	C5—C4—N	125.4 (2)
C3—N—C4	109.75 (19)	C9—C4—N	115.0 (2)
C1—C2—S1	115.56 (18)	C6—C5—C4	118.8 (2)
C1—C2—H5	110.8 (13)	C6—C5—H1	122.2 (13)
S1—C2—H5	109.1 (13)	C4—C5—H1	119.0 (13)
C1—C2—H6	109.9 (13)	C5—C6—C7	121.2 (3)
S1—C2—H6	102.0 (15)	C5—C6—H2	117.9 (14)
H5—C2—H6	109.0 (19)	C7—C6—H2	120.9 (14)
C2—C1—C1^i	111.9 (2)	C8—C7—C6	121.2 (3)
C2—C1—H7	107.6 (11)	C8—C7—H3	121.6 (16)
C1^i—C1—H7	109.8 (12)	C6—C7—H3	117.2 (16)
C2—C1—H8	109.4 (13)	C7—C8—C9	118.1 (2)
C1^i—C1—H8	109.9 (12)	C7—C8—H4	122.2 (13)
H7—C1—H8	108.1 (17)	C9—C8—H4	119.6 (13)
N—C3—S1	126.06 (18)	C8—C9—C4	121.1 (2)
N—C3—S2	117.06 (17)	C8—C9—S2	129.0 (2)
S1—C3—S2	116.88 (14)	C4—C9—S2	109.90 (16)
C3—S1—C2—C1	86.1 (2)	C4—C5—C6—C7	−1.1 (4)
S1—C2—C1—C1^i	177.7 (3)	C5—C6—C7—C8	0.6 (4)
C4—N—C3—S1	−177.95 (15)	C6—C7—C8—C9	0.0 (4)
C4—N—C3—S2	1.2 (2)	C7—C8—C9—C4	−0.1 (3)
C2—S1—C3—N	−10.6 (2)	C7—C8—C9—S2	178.60 (19)
C2—S1—C3—S2	170.25 (13)	C5—C4—C9—C8	−0.4 (3)
C9—S2—C3—N	−1.60 (18)	N—C4—C9—C8	177.75 (19)
C9—S2—C3—S1	177.61 (13)	C5—C4—C9—S2	−179.31 (17)
C3—N—C4—C5	178.0 (2)	N—C4—C9—S2	−1.2 (2)
C3—N—C4—C9	0.0 (3)	C3—S2—C9—C8	−177.4 (2)
C9—C4—C5—C6	1.0 (3)	C3—S2—C9—C4	1.45 (16)
N—C4—C5—C6	−177.0 (2)

Symmetry code: (i) −x+1, −y+1, −z+1.