2–Propyl mesityl sulfone, C12H18O2S, (I), is entirely devoid of the rotational disorder displayed in the corresponding 2-bromo- and 2-chloro-2-propyl mesityl sulfones. Each molecule of (I) hydrogen bonds with four other molecules, each utilizing the acidic α-H atom of its 2-propyl group and a p-methyl-H atom as donors, and its two sulfonyl-O atoms as acceptors, resulting in a structure consisting of two-dimensional layers of hydrogen-bonded molecules.
Supporting information
CCDC reference: 198981
Key indicators
- Single-crystal X-ray study
- T = 296 K
- Mean (C-C) = 0.004 Å
- R factor = 0.036
- wR factor = 0.120
- Data-to-parameter ratio = 15.4
checkCIF results
No syntax errors found
ADDSYM reports no extra symmetry
Compound (I) was prepared from mesitylenethiol and 2-bromopropane; m.p. 347.5–349.0 K (literature: m.p. 353 K; Shostakovskii & Bobrov, 1969), 1H NMR (CDCl3, p.p.m.): δ 1.33, (d, J = 7 Hz, 6 H), 2.27 (s, 3 H), 2.68 (s, 6 H), 3.28 (hep, J = 7 Hz, 1 H), 6.98 (s, 2 H).
The rotational orientations of the methyl groups were determined by the circular Fourier refinement method available in SHELXL97 (Sheldrick, 1997). All H atoms were treated as riding, with C—H distances in the range 0.93–0.98 Å. All methyl groups were allowed to rotate but not to tip.
Data collection: MSC/AFC Diffractometer Control Software
(Molecular Structure Corporation, 1996); cell refinement: MSC/AFC Diffractometer Control Software; data reduction: PROCESS in TEXSAN (Molecular Structure Corporation, 1997); program(s) used to solve structure: SIR92 (Burla et al., 1989); program(s) used to refine structure: LS in TEXSAN and SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2000); software used to prepare material for publication: TEXSAN, SHELXL97, and PLATON (Spek, 2000).
2-Propyl mesityl sulfone
top
Crystal data top
C12H18O2S | Dx = 1.215 Mg m−3 |
Mr = 226.32 | Melting point: 353 K |
Orthorhombic, Pbca | Mo Kα radiation, λ = 0.71069 Å |
a = 18.728 (2) Å | Cell parameters from 25 reflections |
b = 17.0310 (16) Å | θ = 16.6–17.8° |
c = 7.758 (3) Å | µ = 0.24 mm−1 |
V = 2474.5 (9) Å3 | T = 296 K |
Z = 8 | Prism, colorless |
F(000) = 976 | 0.50 × 0.30 × 0.21 mm |
Data collection top
Rigaku AFC-5S diffractometer | Rint = 0.018 |
Radiation source: fine-focus sealed tube | θmax = 25.0°, θmin = 2.2° |
Graphite monochromator | h = 0→22 |
ω scans | k = 0→20 |
2878 measured reflections | l = −9→2 |
2189 independent reflections | 3 standard reflections every 100 reflections |
1386 reflections with I > 2σ(I) | intensity decay: 2.3% |
Refinement top
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.036 | H-atom parameters constrained |
wR(F2) = 0.120 | w = 1/[σ2(Fo2) + (0.0609P)2 + 0.5143P] where P = (Fo2 + 2Fc2)/3 |
S = 1.02 | (Δ/σ)max = 0.001 |
2189 reflections | Δρmax = 0.22 e Å−3 |
142 parameters | Δρmin = −0.22 e Å−3 |
0 restraints | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0046 (8) |
Crystal data top
C12H18O2S | V = 2474.5 (9) Å3 |
Mr = 226.32 | Z = 8 |
Orthorhombic, Pbca | Mo Kα radiation |
a = 18.728 (2) Å | µ = 0.24 mm−1 |
b = 17.0310 (16) Å | T = 296 K |
c = 7.758 (3) Å | 0.50 × 0.30 × 0.21 mm |
Data collection top
Rigaku AFC-5S diffractometer | Rint = 0.018 |
2878 measured reflections | 3 standard reflections every 100 reflections |
2189 independent reflections | intensity decay: 2.3% |
1386 reflections with I > 2σ(I) | |
Refinement top
R[F2 > 2σ(F2)] = 0.036 | 0 restraints |
wR(F2) = 0.120 | H-atom parameters constrained |
S = 1.02 | Δρmax = 0.22 e Å−3 |
2189 reflections | Δρmin = −0.22 e Å−3 |
142 parameters | |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Uiso*/Ueq | |
S1 | 0.60692 (3) | 0.11120 (4) | 0.65916 (9) | 0.0460 (2) | |
O1 | 0.59804 (10) | 0.16247 (12) | 0.8045 (3) | 0.0676 (6) | |
O2 | 0.57660 (9) | 0.03436 (10) | 0.6747 (3) | 0.0620 (5) | |
C1 | 0.70020 (12) | 0.10381 (13) | 0.6124 (3) | 0.0394 (5) | |
C2 | 0.74233 (12) | 0.17221 (14) | 0.6269 (3) | 0.0438 (6) | |
C3 | 0.81501 (13) | 0.16497 (16) | 0.5951 (3) | 0.0526 (7) | |
C4 | 0.84738 (13) | 0.09515 (16) | 0.5506 (3) | 0.0533 (7) | |
C5 | 0.80384 (14) | 0.03023 (16) | 0.5338 (3) | 0.0521 (7) | |
C6 | 0.73103 (12) | 0.03167 (14) | 0.5625 (3) | 0.0443 (6) | |
C7 | 0.69147 (16) | −0.04496 (14) | 0.5362 (4) | 0.0619 (8) | |
C8 | 0.71563 (14) | 0.25325 (14) | 0.6717 (4) | 0.0609 (7) | |
C9 | 0.92635 (15) | 0.0899 (2) | 0.5182 (5) | 0.0828 (10) | |
C10 | 0.56837 (13) | 0.15653 (15) | 0.4733 (4) | 0.0548 (7) | |
C11 | 0.48909 (16) | 0.1714 (2) | 0.5102 (5) | 0.0893 (12) | |
C12 | 0.57917 (17) | 0.10706 (18) | 0.3139 (4) | 0.0700 (8) | |
H3 | 0.8434 | 0.2096 | 0.6044 | 0.063* | |
H5 | 0.8246 | −0.0171 | 0.5012 | 0.063* | |
H7A | 0.7228 | −0.0825 | 0.4834 | 0.093* | |
H7B | 0.6510 | −0.0362 | 0.4628 | 0.093* | |
H7C | 0.6756 | −0.0647 | 0.6456 | 0.093* | |
H8A | 0.7529 | 0.2909 | 0.6520 | 0.091* | |
H8B | 0.7018 | 0.2546 | 0.7908 | 0.091* | |
H8C | 0.6752 | 0.2658 | 0.6008 | 0.091* | |
H9A | 0.9483 | 0.0590 | 0.6071 | 0.124* | |
H9B | 0.9466 | 0.1417 | 0.5186 | 0.124* | |
H9C | 0.9346 | 0.0657 | 0.4083 | 0.124* | |
H10 | 0.5918 | 0.2073 | 0.4553 | 0.066* | |
H11A | 0.4670 | 0.1942 | 0.4104 | 0.134* | |
H11B | 0.4846 | 0.2067 | 0.6061 | 0.134* | |
H11C | 0.4660 | 0.1226 | 0.5372 | 0.134* | |
H12A | 0.5531 | 0.0588 | 0.3255 | 0.105* | |
H12B | 0.6291 | 0.0958 | 0.3002 | 0.105* | |
H12C | 0.5622 | 0.1352 | 0.2148 | 0.105* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
S1 | 0.0408 (3) | 0.0475 (4) | 0.0497 (4) | −0.0042 (3) | 0.0068 (3) | 0.0040 (3) |
O1 | 0.0612 (12) | 0.0794 (13) | 0.0623 (13) | −0.0002 (10) | 0.0184 (10) | −0.0153 (10) |
O2 | 0.0528 (10) | 0.0555 (11) | 0.0777 (14) | −0.0114 (8) | 0.0107 (10) | 0.0194 (10) |
C1 | 0.0381 (12) | 0.0465 (13) | 0.0337 (12) | −0.0039 (10) | 0.0027 (10) | 0.0025 (10) |
C2 | 0.0454 (13) | 0.0477 (13) | 0.0385 (12) | −0.0054 (10) | 0.0005 (11) | −0.0010 (11) |
C3 | 0.0458 (13) | 0.0614 (16) | 0.0507 (15) | −0.0152 (12) | 0.0029 (12) | −0.0037 (13) |
C4 | 0.0414 (14) | 0.0737 (19) | 0.0448 (15) | 0.0000 (12) | −0.0015 (12) | −0.0065 (14) |
C5 | 0.0535 (15) | 0.0580 (15) | 0.0448 (15) | 0.0119 (13) | −0.0022 (12) | −0.0045 (13) |
C6 | 0.0497 (14) | 0.0472 (13) | 0.0359 (12) | 0.0007 (11) | 0.0005 (11) | 0.0024 (11) |
C7 | 0.0743 (19) | 0.0414 (14) | 0.0700 (19) | −0.0018 (13) | 0.0057 (16) | −0.0019 (14) |
C8 | 0.0627 (15) | 0.0491 (14) | 0.0709 (19) | −0.0076 (13) | 0.0072 (15) | −0.0073 (14) |
C9 | 0.0448 (16) | 0.115 (3) | 0.089 (2) | 0.0001 (17) | 0.0039 (16) | −0.028 (2) |
C10 | 0.0435 (14) | 0.0494 (14) | 0.0714 (19) | −0.0042 (12) | −0.0043 (13) | 0.0144 (14) |
C11 | 0.0523 (17) | 0.096 (2) | 0.119 (3) | 0.0122 (17) | −0.0044 (19) | 0.026 (2) |
C12 | 0.0685 (18) | 0.079 (2) | 0.0625 (19) | −0.0067 (16) | −0.0157 (16) | 0.0069 (16) |
Geometric parameters (Å, º) top
S1—O2 | 1.4316 (17) | C7—H7A | 0.9600 |
S1—O1 | 1.436 (2) | C7—H7B | 0.9600 |
S1—C10 | 1.788 (3) | C7—H7C | 0.9600 |
S1—C1 | 1.789 (2) | C8—H8A | 0.9600 |
C1—C6 | 1.412 (3) | C8—H8B | 0.9600 |
C1—C2 | 1.411 (3) | C8—H8C | 0.9600 |
C2—C3 | 1.389 (3) | C9—H9A | 0.9600 |
C2—C8 | 1.509 (3) | C9—H9B | 0.9600 |
C3—C4 | 1.379 (4) | C9—H9C | 0.9600 |
C4—C5 | 1.380 (4) | C10—H10 | 0.9800 |
C4—C9 | 1.503 (4) | C11—H11A | 0.9600 |
C5—C6 | 1.382 (3) | C11—H11B | 0.9600 |
C6—C7 | 1.515 (3) | C11—H11C | 0.9600 |
C10—C12 | 1.510 (4) | C12—H12A | 0.9600 |
C10—C11 | 1.533 (4) | C12—H12B | 0.9600 |
C3—H3 | 0.9300 | C12—H12C | 0.9600 |
C5—H5 | 0.9300 | | |
| | | |
O2—S1—O1 | 116.34 (12) | C6—C7—H7C | 109.5 |
O2—S1—C10 | 107.62 (12) | H7A—C7—H7C | 109.5 |
O1—S1—C10 | 108.91 (13) | H7B—C7—H7C | 109.5 |
O2—S1—C1 | 109.89 (11) | C2—C8—H8A | 109.5 |
O1—S1—C1 | 108.36 (11) | C2—C8—H8B | 109.5 |
C10—S1—C1 | 105.15 (11) | H8A—C8—H8B | 109.5 |
C6—C1—C2 | 120.8 (2) | C2—C8—H8C | 109.5 |
C6—C1—S1 | 121.09 (17) | H8A—C8—H8C | 109.5 |
C2—C1—S1 | 118.16 (17) | H8B—C8—H8C | 109.5 |
C3—C2—C1 | 117.4 (2) | C4—C9—H9A | 109.5 |
C3—C2—C8 | 116.5 (2) | C4—C9—H9B | 109.5 |
C1—C2—C8 | 126.0 (2) | H9A—C9—H9B | 109.5 |
C4—C3—C2 | 123.5 (2) | C4—C9—H9C | 109.5 |
C3—C4—C5 | 117.1 (2) | H9A—C9—H9C | 109.5 |
C3—C4—C9 | 121.7 (3) | H9B—C9—H9C | 109.5 |
C5—C4—C9 | 121.2 (3) | C12—C10—H10 | 108.4 |
C4—C5—C6 | 123.6 (2) | C11—C10—H10 | 108.4 |
C5—C6—C1 | 117.6 (2) | S1—C10—H10 | 108.4 |
C5—C6—C7 | 116.5 (2) | C10—C11—H11A | 109.5 |
C1—C6—C7 | 125.9 (2) | C10—C11—H11B | 109.5 |
C12—C10—C11 | 112.0 (3) | H11A—C11—H11B | 109.5 |
C12—C10—S1 | 111.43 (19) | C10—C11—H11C | 109.5 |
C11—C10—S1 | 108.2 (2) | H11A—C11—H11C | 109.5 |
C4—C3—H3 | 118.2 | H11B—C11—H11C | 109.5 |
C2—C3—H3 | 118.2 | C10—C12—H12A | 109.5 |
C4—C5—H5 | 118.2 | C10—C12—H12B | 109.5 |
C6—C5—H5 | 118.2 | H12A—C12—H12B | 109.5 |
C6—C7—H7A | 109.5 | C10—C12—H12C | 109.5 |
C6—C7—H7B | 109.5 | H12A—C12—H12C | 109.5 |
H7A—C7—H7B | 109.5 | H12B—C12—H12C | 109.5 |
| | | |
O2—S1—C1—C6 | 12.6 (2) | C3—C4—C5—C6 | −1.4 (4) |
O1—S1—C1—C6 | 140.7 (2) | C9—C4—C5—C6 | 179.7 (3) |
C10—S1—C1—C6 | −102.9 (2) | C4—C5—C6—C1 | −0.2 (4) |
O2—S1—C1—C2 | −167.34 (18) | C4—C5—C6—C7 | 179.4 (2) |
O1—S1—C1—C2 | −39.2 (2) | C2—C1—C6—C5 | 1.9 (3) |
C10—S1—C1—C2 | 77.1 (2) | S1—C1—C6—C5 | −178.07 (18) |
C6—C1—C2—C3 | −1.8 (3) | C2—C1—C6—C7 | −177.7 (2) |
S1—C1—C2—C3 | 178.12 (19) | S1—C1—C6—C7 | 2.4 (3) |
C6—C1—C2—C8 | 177.4 (2) | O2—S1—C10—C12 | −55.8 (2) |
S1—C1—C2—C8 | −2.7 (3) | O1—S1—C10—C12 | 177.25 (18) |
C1—C2—C3—C4 | 0.1 (4) | C1—S1—C10—C12 | 61.3 (2) |
C8—C2—C3—C4 | −179.2 (3) | O2—S1—C10—C11 | 67.7 (2) |
C2—C3—C4—C5 | 1.5 (4) | O1—S1—C10—C11 | −59.2 (2) |
C2—C3—C4—C9 | −179.7 (3) | C1—S1—C10—C11 | −175.2 (2) |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
C9—H9C···O2i | 0.96 | 2.50 | 3.403 (4) | 158 |
C10—H10···O1ii | 0.98 | 2.51 | 3.395 (4) | 150 |
Symmetry codes: (i) −x+3/2, −y, z−1/2; (ii) x, −y+1/2, z−1/2. |
Experimental details
Crystal data |
Chemical formula | C12H18O2S |
Mr | 226.32 |
Crystal system, space group | Orthorhombic, Pbca |
Temperature (K) | 296 |
a, b, c (Å) | 18.728 (2), 17.0310 (16), 7.758 (3) |
V (Å3) | 2474.5 (9) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.24 |
Crystal size (mm) | 0.50 × 0.30 × 0.21 |
|
Data collection |
Diffractometer | Rigaku AFC-5S diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 2878, 2189, 1386 |
Rint | 0.018 |
(sin θ/λ)max (Å−1) | 0.596 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.036, 0.120, 1.02 |
No. of reflections | 2189 |
No. of parameters | 142 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.22, −0.22 |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
C9—H9C···O2i | 0.96 | 2.50 | 3.403 (4) | 158 |
C10—H10···O1ii | 0.98 | 2.51 | 3.395 (4) | 150 |
Symmetry codes: (i) −x+3/2, −y, z−1/2; (ii) x, −y+1/2, z−1/2. |
We have reported that crystalline 2-bromo-2-propyl mesityl sulfone, (II) (Chan-Yu-King et al., 2001), 2-chloro-2-propyl mesityl sulfone, (III) (Meyers et al., 2001), and a related ketone, 2-bromo-2-propyl 2-(5-tert-butyl-1,3-xylyl) ketone, (IV) (Robinson, Sandrock et al., 2001), all exhibit rotational disorder, while 2-bromo-2-propyl phenyl sulfone, (V) (Robinson, Parady et al., 2001), and dichloromethyl phenyl sulfone, (VI) (Chan-Yu-King et al., 2002), do not. To learn more about the relationship between structure and rotational disorder, we have now examined crystalline 2-propyl mesityl sulfone, (I), the only 2-propyl mesityl structure in this series possessing an α-H atom.
The structure of (I), prepared as illustrated (see Scheme), is shown with its atom numbering in Fig. 1. An important aspect of this structure resides in its extensive hydrogen bonding, shown in Fig. 2. Each molecule hydrogen bonds with four mirror-image molecules, each utilizing the acidic α-H atom of its 2-propyl group and a p-methyl-H atom, as well as its two sulfonyl-O atoms as acceptors. Hydrogen-bond geometry is given in Table 1. As a consequence, the molecular packing consists of two-dimensional layers of intermoleculary hydrogen-bonded molecules. Four such layers, in an edge-on configuration normal to [100], are shown in Fig. 3.
This information suggests that rotational disorder in crystalline mesityl 2-propyl sulfones and ketones, e.g. (II), (III) and (IV), is associated with a combination of the steric effect of the mesityl group and absence of intermolecular hydrogen bonding involving an acidic α-H atom. In such a situation, crystallization would provide a packing structure of molecules without a common conformation of their 2-propyl group. This reasoning would account for the absence of rotational disorder in (I) (possessing a mesityl group and an acidic α-H atom providing extensive intermolecular hydrogen bonding with the sulfonyl group), (V) (possessing neither a mesityl group nor α-H atom) and (VI) (possessing an α-H atom but no mesityl group).
The effect of intermolecular hydrogen bonding in reducing intermolecular proximity and, thus, rotational disorder, in the packing structure is illustrated by the following example. In compound (II), which exhibits extensive rotational disorder (Chan-Yu-King et al., 2001), the intermolecular distance between atoms O1 and Br1 is 0.13 Å greater than the sum of their van der Waals radii. But, in compound (I), showing no rotational disorder, the intermolecular distance between the corresponding, but ostensibly hydrogen-bonded atoms O1 and H10 is 0.21 Å less than the sum of their van der Waals radii, and even its O1···C10 distance is only 0.17 Å greater than the sum of its van der Waals radii.