Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536803010523/bt6279sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536803010523/bt6279Isup2.hkl |
CCDC reference: 214843
Key indicators
- Single-crystal X-ray study
- T = 187 K
- Mean (C-C) = 0.003 Å
- R factor = 0.048
- wR factor = 0.134
- Data-to-parameter ratio = 18.1
checkCIF results
No syntax errors found ADDSYM reports no extra symmetry
Alert Level B:
RINTA_01 Alert B The value of Rint is greater than 0.15 Rint given 0.169
0 Alert Level A = Potentially serious problem
1 Alert Level B = Potential problem
0 Alert Level C = Please check
Butanedithiol diacetate, (I), was obtained as a by-product in the synthesis of 1,4-butanedithiol monoacetate, (II), in a procedure similar to the preparation of ethanedithiol monoacetate and ethanedithiol diacetate (Wiesler et al., 1996; Fleischer & Schollmeyer, 2001). Crystals of (I) precipitated at 278 K from its solution in (II). They were washed with cold petroleum ether and identified by elemental analysis and 1H NMR.
Chemically equivalent H atoms were refined isotropically with the same displacement parameters. The two different groups of H atoms due to the disordering of the methyl group were treated with two independent displacement parameters. [The CIF contains no H-atom geometry; please supply these data for inclusion in the final CIF]
Data collection: CAD-4 Software (Enraf-Nonius, 1989); cell refinement: CAD-4 Software; data reduction: CORINC (Dräger & Gattow, 1971); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: please supply; software used to prepare material for publication: please supply.
C8H14O2S2 | F(000) = 220 |
Mr = 206.31 | Dx = 1.310 Mg m−3 |
Monoclinic, P21/c | Cu Kα radiation, λ = 1.54178 Å |
a = 6.1998 (7) Å | Cell parameters from 25 reflections |
b = 8.0292 (7) Å | θ = 57–73° |
c = 10.565 (1) Å | µ = 4.31 mm−1 |
β = 95.942 (4)° | T = 187 K |
V = 523.09 (9) Å3 | Block, colorless |
Z = 2 | 0.25 × 0.20 × 0.15 mm |
Enraf–Nonius CAD-4 diffractometer | 908 reflections with I > 2σ(I) |
Radiation source: rotating anode | Rint = 0.169 |
Graphite monochromator | θmax = 73.8°, θmin = 6.9° |
θ/2ω scans | h = −7→7 |
Absorption correction: ψ scan (CORINC; Dräger & Gattow, 1971) | k = 0→10 |
Tmin = 0.383, Tmax = 0.524 | l = 0→13 |
1126 measured reflections | 3 standard reflections every 60 min |
1067 independent reflections | intensity decay: 5% |
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)] = 0.048 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.134 | H-atom parameters constrained |
S = 1.12 | w = 1/[σ2(Fo2) + (0.0915P)2] where P = (Fo2 + 2Fc2)/3 |
1067 reflections | (Δ/σ)max < 0.001 |
59 parameters | Δρmax = 0.34 e Å−3 |
0 restraints | Δρmin = −0.84 e Å−3 |
C8H14O2S2 | V = 523.09 (9) Å3 |
Mr = 206.31 | Z = 2 |
Monoclinic, P21/c | Cu Kα radiation |
a = 6.1998 (7) Å | µ = 4.31 mm−1 |
b = 8.0292 (7) Å | T = 187 K |
c = 10.565 (1) Å | 0.25 × 0.20 × 0.15 mm |
β = 95.942 (4)° |
Enraf–Nonius CAD-4 diffractometer | 908 reflections with I > 2σ(I) |
Absorption correction: ψ scan (CORINC; Dräger & Gattow, 1971) | Rint = 0.169 |
Tmin = 0.383, Tmax = 0.524 | 3 standard reflections every 60 min |
1126 measured reflections | intensity decay: 5% |
1067 independent reflections |
R[F2 > 2σ(F2)] = 0.048 | 0 restraints |
wR(F2) = 0.134 | H-atom parameters constrained |
S = 1.12 | Δρmax = 0.34 e Å−3 |
1067 reflections | Δρmin = −0.84 e Å−3 |
59 parameters |
Experimental. ψ scans using CORINC (Dräger, 1971) |
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. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
C1 | 0.5767 (4) | 0.4575 (3) | 0.4587 (2) | 0.0251 (5) | |
H1A | 0.7275 | 0.4885 | 0.4896 | 0.032 (5)* | |
H1B | 0.5468 | 0.4987 | 0.3704 | 0.032 (5)* | |
C2 | 0.5571 (4) | 0.2683 (3) | 0.4584 (2) | 0.0268 (5) | |
H2A | 0.6432 | 0.2226 | 0.3926 | 0.037 (5)* | |
H2B | 0.4036 | 0.2376 | 0.4347 | 0.037 (5)* | |
S3 | 0.64823 (9) | 0.17358 (7) | 0.60986 (5) | 0.0284 (3) | |
C4 | 0.9309 (4) | 0.1645 (3) | 0.6010 (2) | 0.0287 (6) | |
O5 | 1.0158 (3) | 0.2125 (3) | 0.50988 (18) | 0.0392 (5) | |
C6 | 1.0538 (5) | 0.0903 (4) | 0.7179 (3) | 0.0430 (7) | |
H6A | 0.9519 | 0.0604 | 0.7792 | 0.044 (11)* | 0.48 |
H6B | 1.1584 | 0.1719 | 0.7564 | 0.044 (11)* | 0.48 |
H6C | 1.1309 | −0.0096 | 0.6942 | 0.044 (11)* | 0.48 |
H6D | 1.2089 | 0.0880 | 0.7074 | 0.062 (12)* | 0.52 |
H6E | 1.0024 | −0.0234 | 0.7302 | 0.062 (12)* | 0.52 |
H6F | 1.0299 | 0.1581 | 0.7924 | 0.062 (12)* | 0.52 |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0297 (12) | 0.0258 (11) | 0.0197 (10) | 0.0031 (9) | 0.0025 (9) | 0.0007 (8) |
C2 | 0.0316 (12) | 0.0266 (11) | 0.0209 (10) | 0.0038 (9) | −0.0039 (8) | −0.0027 (9) |
S3 | 0.0317 (4) | 0.0310 (4) | 0.0224 (4) | 0.0026 (2) | 0.0028 (2) | 0.0055 (2) |
C4 | 0.0326 (13) | 0.0279 (12) | 0.0243 (12) | 0.0045 (9) | −0.0034 (9) | −0.0045 (9) |
O5 | 0.0342 (10) | 0.0471 (11) | 0.0371 (10) | 0.0007 (8) | 0.0076 (8) | 0.0053 (8) |
C6 | 0.0446 (15) | 0.0516 (17) | 0.0300 (13) | 0.0145 (13) | −0.0102 (11) | −0.0019 (12) |
C1—C1i | 1.517 (4) | S3—C4 | 1.766 (3) |
C1—C2 | 1.523 (3) | C4—O5 | 1.207 (3) |
C2—S3 | 1.809 (2) | C4—C6 | 1.506 (3) |
C1i—C1—C2 | 113.3 (2) | O5—C4—C6 | 123.7 (3) |
C1—C2—S3 | 113.55 (15) | O5—C4—S3 | 123.1 (2) |
C4—S3—C2 | 101.02 (12) | C6—C4—S3 | 113.2 (2) |
C1i—C1—C2—S3 | −67.6 (3) | C2—S3—C4—C6 | 179.51 (18) |
C1—C2—S3—C4 | −82.70 (19) | C2—C1—C1i—C2i | 180.0 |
C2—S3—C4—O5 | −0.8 (2) |
Symmetry code: (i) −x+1, −y+1, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C8H14O2S2 |
Mr | 206.31 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 187 |
a, b, c (Å) | 6.1998 (7), 8.0292 (7), 10.565 (1) |
β (°) | 95.942 (4) |
V (Å3) | 523.09 (9) |
Z | 2 |
Radiation type | Cu Kα |
µ (mm−1) | 4.31 |
Crystal size (mm) | 0.25 × 0.20 × 0.15 |
Data collection | |
Diffractometer | Enraf–Nonius CAD-4 diffractometer |
Absorption correction | ψ scan (CORINC; Dräger & Gattow, 1971) |
Tmin, Tmax | 0.383, 0.524 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 1126, 1067, 908 |
Rint | 0.169 |
(sin θ/λ)max (Å−1) | 0.623 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.048, 0.134, 1.12 |
No. of reflections | 1067 |
No. of parameters | 59 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.34, −0.84 |
Computer programs: CAD-4 Software (Enraf-Nonius, 1989), CAD-4 Software, CORINC (Dräger & Gattow, 1971), SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 1997), please supply.
XRD | DF | |
C1-C1a | 1.517 (4) | 1.534 |
C1-C2 | 1.523 (3) | 1.527 |
C2-S3 | 1.809 (2) | 1.834 |
S3-C4 | 1.766 (3) | 1.795 |
C4-C6) | 1.506 (3) | 1.512 |
C4-O5 | 1.207 (3) | 1.205 |
C1a-C1-C2 | 113.3 (2) | 111.6 |
C1-C2-S3 | 113.6 (2) | 110.4 |
C2-S3-C4 | 101.0 (1) | 100.1 |
S3-C4-C6 | 113.2 (2) | 113.6 |
O5-C4-C6 | 123.7 (3) | 123.5 |
O5-C4-S3 | 123.1 (2) | 122.9 |
C1a-C1-C2-S3 | 67.6 (3) | 179.9 |
C1-C2-S3-C4 | 82.7 (2) | 182.1 |
C2-S3-C4-O5 | 0.8 (2) | 0.3 |
C2-S3-C4-C6 | 179.5 (2) | 180.5 |
Symmetry code: (i) 1 − x, 1 − y, 1 − z. |
Thioesters are very important acetylating agents in biochemical processes, as well as in many chemical transformations (Nicolaou, 1977; Hirama et al., 1979; Zheng et al., 1999). We obtained butanedithiol diacetate, H3CC(O)SCH2CH2CH2CH2SC(O)CH3, (I), as a by-product in the synthesis of 1,4-butanedithiol monoacetate, HSCH2CH2CH2CH2SC(O)CH3, (II), in a procedure similar to the preparation of ethanedithiol monoacetate and ethanedithiol diacetate (Wiesler et al., 1996; Fleischer & Schollmeyer, 2001). Crystals of (I) precipitated at 278 K from its solution in (II). They were washed with cold petrol ether and identified by elemental analysis and 1H NMR. One of them was selected for single-crystal X-ray diffraction.
The molecular structure of (I) as found in the solid state is depicted in Fig. 1. Table 1 shows selected structural parameters from the XRD experiment in comparison to those obtained by a density functional (DF) geometry optimization. The molecular structure was first optimized at the Hartree–Fock level with a 6–31 G(d) basis set, starting from the molecular structure as found in the solid state. Subsequently the structure was re-optimized employing density functional theory (DFT) and a larger basis set [B3LYP/6–311+G(2,p)]. Apart from the two S—C and the C1—C1a distances, the DF bond lengths and angles agree quite well with the experimental values. The torsion angles C1a—C1—C2—S3 and C1—C2—S3—C4 differ substantially between the solid state and the DF-calculated isolated molecule. We attribute the differences in the bond distances mentioned to the chosen level of theory, but the difference in torsion angles to intermolecular hydrogen bridges in the solid state [O5i···C6 = 3.497 (3) Å and O5i···H—C6 = 168.1 (2)°; symmetry code: (i) x, 1/2 − y, 1/2 + z]. The structural parameters of (I) agree well with those found for other compounds exhibiting an S-acetyl moiety (Fleischer & Schollmeyer, 2001; Evans et al., 1999; Divajakovic et al., 1992; Mackay et al., 1992; Huber et al., 1984; Mattes & Waldmann, 1983; Mattes et al., 1977; Kiel et al., 1974). This implies that the S-acetyl fragment is a relatively rigid structural unit, a hypothesis supported by an analysis of the bonding situation in terms of natural bond orbitals (Fleischer & Schollmeyer, 2001).