The title compound, C11H26P2S2, displays crystallographic mirror symmetry. Key bond lengths (Å) are P1-C(methylene) 1.8464 (18), P1-C(butyl) 1.8711 (13), P2-C(methylene) 1.8266 (18), P2-C(methyl) 1.7948 (15), P1=S 1.9631 (8) and P2=S 1.9552 (8), where P1 is the di-tert-butylphosphino P atom and P2 is the dimethylphosphino P atom. The angle P-C-P [124.31 (10)°] is wide and S=P-C(methylene) [108.91 (6)°] narrow. Steric pressure from the tert-butyl groups may cause some of the molecular dimensions to depart from normal values.
Supporting information
CCDC reference: 197478
Key indicators
- Single-crystal X-ray study
- T = 143 K
- Mean (C-C) = 0.002 Å
- R factor = 0.027
- wR factor = 0.072
- Data-to-parameter ratio = 23.2
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: 0.698 0.769
RT(exp) = 1.101
0 Alert Level A = Potentially serious problem
0 Alert Level B = Potential problem
1 Alert Level C = Please check
Attempts to recrystallize bis[(di-tert-butylphosphanyl)methyl]methylphosphane trisulfide (Krill et al., 1993) from diethyl ether–toluene led unexpectedly to crystals of the title compound.
The methylene H atoms were included using a riding model, while methyl H atoms were identified in difference syntheses and refined using idealized rigid methyl groups allowed to rotate but not tip. C—H bond lengths were fixed at 0.98 and 0.99 Å for methyl and methylene H atoms, respectively; Uiso(H) values were fixed at 1.2 times the Ueq values of the parent atom.
Data collection: DIF4 (Stoe & Cie, 1992); cell refinement: DIF4; data reduction: REDU4 (Stoe & Cie, 1992); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP (Siemens, 1994); software used to prepare material for publication: SHELXL97.
(Di-
tert-butylphosphino)(dimethylphosphino)methane disulfide
top
Crystal data top
C11H26P2S2 | Dx = 1.225 Mg m−3 |
Mr = 284.38 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, Pnma | Cell parameters from 52 reflections |
a = 18.298 (5) Å | θ = 10–11.5° |
b = 12.792 (3) Å | µ = 0.53 mm−1 |
c = 6.586 (2) Å | T = 143 K |
V = 1541.6 (7) Å3 | Tablet, colourless |
Z = 4 | 0.7 × 0.6 × 0.5 mm |
F(000) = 616 | |
Data collection top
Stoe STADI-4 diffractometer | Rint = 0.020 |
Radiation source: fine-focus sealed tube | θmax = 27.5°, θmin = 3.2° |
Graphite monochromator | h = −2→23 |
ω/θ scans | k = −9→16 |
2346 measured reflections | l = −8→8 |
1854 independent reflections | 3 standard reflections every 60 min |
1712 reflections with I > 2σ(I) | intensity decay: none |
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)] = 0.027 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.072 | H-atom parameters constrained |
S = 1.07 | w = 1/[σ2(Fo2) + (0.0363P)2 + 0.6264P] where P = (Fo2 + 2Fc2)/3 |
1854 reflections | (Δ/σ)max < 0.001 |
80 parameters | Δρmax = 0.37 e Å−3 |
0 restraints | Δρmin = −0.35 e Å−3 |
Crystal data top
C11H26P2S2 | V = 1541.6 (7) Å3 |
Mr = 284.38 | Z = 4 |
Orthorhombic, Pnma | Mo Kα radiation |
a = 18.298 (5) Å | µ = 0.53 mm−1 |
b = 12.792 (3) Å | T = 143 K |
c = 6.586 (2) Å | 0.7 × 0.6 × 0.5 mm |
Data collection top
Stoe STADI-4 diffractometer | Rint = 0.020 |
2346 measured reflections | 3 standard reflections every 60 min |
1854 independent reflections | intensity decay: none |
1712 reflections with I > 2σ(I) | |
Refinement top
R[F2 > 2σ(F2)] = 0.027 | 0 restraints |
wR(F2) = 0.072 | H-atom parameters constrained |
S = 1.07 | Δρmax = 0.37 e Å−3 |
1854 reflections | Δρmin = −0.35 e Å−3 |
80 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 | Uiso*/Ueq | Occ. (<1) |
P1 | 0.31790 (2) | 0.2500 | 0.54645 (7) | 0.01640 (12) | |
P2 | 0.14937 (2) | 0.2500 | 0.39177 (7) | 0.01930 (12) | |
S1 | 0.27809 (3) | 0.2500 | 0.82324 (7) | 0.02627 (13) | |
S2 | 0.09816 (2) | 0.2500 | 0.13121 (8) | 0.02721 (13) | |
C1 | 0.24776 (9) | 0.2500 | 0.3449 (3) | 0.0183 (3) | |
H1A | 0.2578 | 0.3120 | 0.2593 | 0.022* | 0.50 |
H1B | 0.2578 | 0.1880 | 0.2593 | 0.022* | 0.50 |
C2 | 0.37053 (7) | 0.12709 (10) | 0.4981 (2) | 0.0215 (3) | |
C3 | 0.31620 (8) | 0.03668 (11) | 0.5275 (3) | 0.0323 (3) | |
H3A | 0.2930 | 0.0429 | 0.6610 | 0.039* | |
H3B | 0.3423 | −0.0301 | 0.5190 | 0.039* | |
H3C | 0.2787 | 0.0396 | 0.4214 | 0.039* | |
C4 | 0.43156 (8) | 0.11512 (13) | 0.6569 (2) | 0.0332 (3) | |
H4A | 0.4115 | 0.1273 | 0.7928 | 0.040* | |
H4B | 0.4703 | 0.1661 | 0.6294 | 0.040* | |
H4C | 0.4518 | 0.0443 | 0.6497 | 0.040* | |
C5 | 0.40353 (7) | 0.12033 (11) | 0.2851 (2) | 0.0273 (3) | |
H5A | 0.3661 | 0.1376 | 0.1842 | 0.033* | |
H5B | 0.4215 | 0.0492 | 0.2610 | 0.033* | |
H5C | 0.4442 | 0.1699 | 0.2737 | 0.033* | |
C6 | 0.12750 (7) | 0.13849 (12) | 0.5456 (2) | 0.0305 (3) | |
H6A | 0.1415 | 0.0745 | 0.4738 | 0.037* | |
H6B | 0.0748 | 0.1374 | 0.5726 | 0.037* | |
H6C | 0.1542 | 0.1427 | 0.6743 | 0.037* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
P1 | 0.0162 (2) | 0.0201 (2) | 0.0128 (2) | 0.000 | −0.00066 (15) | 0.000 |
P2 | 0.0150 (2) | 0.0220 (2) | 0.0209 (2) | 0.000 | 0.00108 (17) | 0.000 |
S1 | 0.0276 (2) | 0.0375 (3) | 0.0138 (2) | 0.000 | 0.00258 (17) | 0.000 |
S2 | 0.0181 (2) | 0.0360 (3) | 0.0276 (3) | 0.000 | −0.00591 (18) | 0.000 |
C1 | 0.0155 (7) | 0.0239 (8) | 0.0154 (8) | 0.000 | −0.0010 (6) | 0.000 |
C2 | 0.0215 (6) | 0.0211 (6) | 0.0217 (6) | 0.0031 (5) | −0.0024 (5) | 0.0002 (5) |
C3 | 0.0327 (7) | 0.0212 (6) | 0.0429 (9) | −0.0007 (5) | 0.0020 (6) | 0.0034 (6) |
C4 | 0.0297 (7) | 0.0388 (8) | 0.0310 (7) | 0.0103 (6) | −0.0084 (6) | 0.0015 (7) |
C5 | 0.0256 (6) | 0.0297 (7) | 0.0266 (7) | 0.0054 (5) | 0.0027 (5) | −0.0052 (6) |
C6 | 0.0251 (7) | 0.0332 (7) | 0.0331 (8) | −0.0059 (5) | 0.0039 (6) | 0.0082 (6) |
Geometric parameters (Å, º) top
P1—C1 | 1.8464 (18) | C3—H3B | 0.9800 |
P1—C2 | 1.8711 (13) | C3—H3C | 0.9800 |
P1—S1 | 1.9631 (8) | C4—H4A | 0.9800 |
P2—C6 | 1.7948 (15) | C4—H4B | 0.9800 |
P2—C1 | 1.8266 (18) | C4—H4C | 0.9800 |
P2—S2 | 1.9552 (8) | C5—H5A | 0.9800 |
C1—H1A | 0.9900 | C5—H5B | 0.9800 |
C1—H1B | 0.9900 | C5—H5C | 0.9800 |
C2—C5 | 1.5296 (19) | C6—H6A | 0.9800 |
C2—C3 | 1.5373 (19) | C6—H6B | 0.9800 |
C2—C4 | 1.5377 (18) | C6—H6C | 0.9800 |
C3—H3A | 0.9800 | | |
| | | |
C1—P1—C2 | 103.61 (5) | H3A—C3—H3B | 109.5 |
C2—P1—C2i | 114.34 (8) | C2—C3—H3C | 109.5 |
C1—P1—S1 | 114.18 (6) | H3A—C3—H3C | 109.5 |
C2—P1—S1 | 110.43 (5) | H3B—C3—H3C | 109.5 |
C6i—P2—C6 | 105.27 (11) | C2—C4—H4A | 109.5 |
C6—P2—C1 | 108.37 (6) | C2—C4—H4B | 109.5 |
C6—P2—S2 | 112.87 (5) | H4A—C4—H4B | 109.5 |
C1—P2—S2 | 108.91 (6) | C2—C4—H4C | 109.5 |
P2—C1—P1 | 124.31 (10) | H4A—C4—H4C | 109.5 |
P2—C1—H1A | 106.2 | H4B—C4—H4C | 109.5 |
P1—C1—H1A | 106.2 | C2—C5—H5A | 109.5 |
P2—C1—H1B | 106.2 | C2—C5—H5B | 109.5 |
P1—C1—H1B | 106.3 | H5A—C5—H5B | 109.5 |
H1A—C1—H1B | 106.4 | C2—C5—H5C | 109.5 |
C5—C2—C3 | 109.18 (11) | H5A—C5—H5C | 109.5 |
C5—C2—C4 | 109.36 (11) | H5B—C5—H5C | 109.5 |
C3—C2—C4 | 107.99 (12) | P2—C6—H6A | 109.5 |
C5—C2—P1 | 114.00 (9) | P2—C6—H6B | 109.5 |
C3—C2—P1 | 106.13 (9) | H6A—C6—H6B | 109.5 |
C4—C2—P1 | 109.97 (10) | P2—C6—H6C | 109.5 |
C2—C3—H3A | 109.5 | H6A—C6—H6C | 109.5 |
C2—C3—H3B | 109.5 | H6B—C6—H6C | 109.5 |
| | | |
C6—P2—C1—P1 | −56.87 (6) | C1—P1—C2—C3 | −62.98 (11) |
S2—P2—C1—P1 | 180.0 | C2i—P1—C2—C3 | −175.03 (7) |
C2—P1—C1—P2 | 120.17 (5) | S1—P1—C2—C3 | 59.71 (10) |
S1—P1—C1—P2 | 0.0 | C1—P1—C2—C4 | −179.55 (10) |
C1—P1—C2—C5 | 57.22 (11) | C2i—P1—C2—C4 | 68.40 (13) |
C2i—P1—C2—C5 | −54.83 (13) | S1—P1—C2—C4 | −56.86 (10) |
S1—P1—C2—C5 | 179.91 (8) | | |
Symmetry code: (i) x, −y+1/2, z. |
Experimental details
Crystal data |
Chemical formula | C11H26P2S2 |
Mr | 284.38 |
Crystal system, space group | Orthorhombic, Pnma |
Temperature (K) | 143 |
a, b, c (Å) | 18.298 (5), 12.792 (3), 6.586 (2) |
V (Å3) | 1541.6 (7) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.53 |
Crystal size (mm) | 0.7 × 0.6 × 0.5 |
|
Data collection |
Diffractometer | Stoe STADI-4 diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 2346, 1854, 1712 |
Rint | 0.020 |
(sin θ/λ)max (Å−1) | 0.650 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.027, 0.072, 1.07 |
No. of reflections | 1854 |
No. of parameters | 80 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.37, −0.35 |
Selected geometric parameters (Å, º) topP1—C1 | 1.8464 (18) | P2—C6 | 1.7948 (15) |
P1—C2 | 1.8711 (13) | P2—C1 | 1.8266 (18) |
P1—S1 | 1.9631 (8) | P2—S2 | 1.9552 (8) |
| | | |
C1—P1—C2 | 103.61 (5) | C6—P2—C1 | 108.37 (6) |
C2—P1—C2i | 114.34 (8) | C6—P2—S2 | 112.87 (5) |
C1—P1—S1 | 114.18 (6) | C1—P2—S2 | 108.91 (6) |
C2—P1—S1 | 110.43 (5) | P2—C1—P1 | 124.31 (10) |
C6i—P2—C6 | 105.27 (11) | | |
| | | |
S2—P2—C1—P1 | 180.0 | S1—P1—C1—P2 | 0.0 |
C2—P1—C1—P2 | 120.17 (5) | C1—P1—C2—C4 | −179.55 (10) |
Symmetry code: (i) x, −y+1/2, z. |
The title compound, (I), arose as an unexpected product during studies of triphosphines (Krill et al., 1993; see Experimental). The molecule, which is shown in Fig. 1, displays crystallographic mirror symmetry, with both P and S atoms and the central atom C1 lying in the mirror plane at y = 0.25. The configuration about the bond P1—C1 is that atoms S1 and P2 are exactly synperiplanar; in contrast, atoms S2 and P1 are exactly antiperiplanar about C1—P2. A search of the Cambridge Structural Database (Allen & Kennard, 1993; Version of April 2002) revealed only one other bis(dialkyl)phosphinomethane disulfide, namely the tetramethyl analogue, henceforth `Me4' (Karsch et al., 1992); this has no imposed symmetry (but twofold symmetry to a close approximation) and has S—P—C—P torsion angles of 48.4 and 48.7 (5)°.
Selected molecular dimensions for (I) are presented in Table 1. The P═S and P—C(methylene) bond lengths in (I) are comparable with those of Me4 [P═S 1.958 (1) and 1.960 (1) Å, and P—C 1.822 (2) and 1.818 (2) Å], although P—C2 is slightly longer. This may be attributable to the steric pressure of the bulky tert-butyl group, as may the appreciably different bond lengths P1—C2 and P2—C6. The bond angle S1═P1—C1 appears normal [cf. Me4; 115.5 (1) and 116.6 (1)°], but S2═P2—C1 is unusually narrow at 108.91 (6)°. The angle at the methylene C atom is wide [cf. Me4 119.0 (1)°], which may also be caused by steric effects; comparable structures for a more detailed analysis are not available.