Iso­propyl 2,4,6-triiso­propyl­phenyl sulfone: an aryl sulfone with unusual atom deviations from the aromatic least-squares plane

Iso­propyl 2,4,6-triiso­propyl­phenyl sulfone, C₁₈H₃₀O₂S, (I), has been synthesized for the first time. In spite of the bulky iso­propyl substituents on both ortho positions, crystalline (I) does not exhibit rotational disorder of the iso­propyl group bonded to the sulfonyl. In contrast, the corresponding bromo- and chloro­iso­propyl groups of crystalline aryl sulfones possessing much smaller di-ortho-methyl substituents display striking rotational disorder. While the aryl rings of the latter compounds are essentially planar, considerable atom deviation from the aromatic least-squares plane of (I) was observed. None of the intra- or intermolecular distances between the methyl C atoms of the sulfonyl­iso­propyl group and those of the two ortho-iso­propyl groups of (I) is shorter than the sum of their van der Waals radii, making it unlikely that they would interfere with the rotation of the α-iso­propyl group prior to crystallization.

Key indicators

• Single-crystal X-ray study
• T = 295 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.047
• wR factor = 0.134
• Data-to-parameter ratio = 16.8

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT220_ALERT_2_C Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       3.34 Ratio
PLAT222_ALERT_3_C Large Non-Solvent    H     Ueq(max)/Ueq(min) ...       3.54 Ratio
PLAT242_ALERT_2_C Check Low    U(eq) as Compared to Neighbors ....         C8
PLAT242_ALERT_2_C Check Low    U(eq) as Compared to Neighbors ....        C10

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   4 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: SMART (Bruker, 2001); cell refinement: SMART; data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SIR92 (Burla et al., 1989); program(s) used to refine structure: LS in TEXSAN (Molecular Structure Corporation, 1997) 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, 2003).

2,4,6-Triisopropylphenyl isopropyl sulfone

Crystal data

C18H30O2S	Dx = 1.092 Mg m^−3
Mr = 310.49	Melting point = 393–395 K
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 7039 reflections
a = 17.4705 (6) Å	θ = 2.4–25.1°
b = 11.5964 (4) Å	µ = 0.17 mm^−1
c = 18.6412 (7) Å	T = 295 K
V = 3776.6 (2) Å^3	Rectangular, colorless
Z = 8	0.44 × 0.31 × 0.10 mm
F(000) = 1360

Data collection

Bruker SMART CCD area-detector diffractometer	2530 reflections with I > 2σ(I)
Radiation source: sealed tube	Rint = 0.048
Graphite monochromator	θmax = 25.0°, θmin = 2.2°
φ and ω scans	h = −20→20
47817 measured reflections	k = −13→13
3319 independent reflections	l = −22→22

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.047	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.134	H-atom parameters constrained
S = 1.02	w = 1/[σ^2(Fo^2) + (0.0682P)^2 + 1.2339P] where P = (Fo^2 + 2Fc^2)/3
3319 reflections	(Δ/σ)max < 0.001
198 parameters	Δρmax = 0.26 e Å^−3
0 restraints	Δρmin = −0.22 e Å^−3

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

	x	y	z	Uiso*/Ueq
S1	0.26750 (3)	0.18789 (4)	0.68743 (3)	0.0530 (2)
O1	0.29869 (9)	0.26676 (13)	0.73887 (9)	0.0719 (5)
O2	0.19212 (9)	0.21430 (15)	0.66199 (9)	0.0729 (5)
C1	0.33006 (11)	0.17647 (16)	0.61105 (11)	0.0482 (5)
C2	0.40502 (12)	0.22266 (17)	0.61247 (12)	0.0528 (5)
C3	0.44467 (13)	0.22577 (19)	0.54772 (13)	0.0620 (6)
C4	0.41564 (14)	0.18375 (19)	0.48372 (13)	0.0639 (6)
C5	0.34502 (14)	0.13205 (19)	0.48617 (12)	0.0623 (6)
C6	0.30062 (12)	0.12626 (17)	0.54746 (11)	0.0543 (5)
C7	0.44725 (13)	0.2693 (2)	0.67762 (13)	0.0650 (6)
C8	0.46094 (18)	0.1940 (3)	0.41454 (16)	0.0896 (9)
C9	0.22496 (13)	0.0613 (2)	0.54023 (13)	0.0647 (6)
C10	0.26564 (12)	0.04734 (18)	0.72788 (12)	0.0566 (5)
C11	0.21031 (17)	0.0509 (3)	0.79086 (15)	0.0884 (8)
C12	0.34410 (14)	0.0074 (2)	0.74870 (16)	0.0807 (8)
C13	0.52705 (16)	0.2171 (3)	0.68480 (17)	0.0924 (9)
C14	0.45244 (18)	0.4007 (2)	0.67426 (18)	0.0953 (9)
C15	0.5264 (3)	0.1173 (3)	0.4121 (2)	0.161 (2)
C16	0.4773 (2)	0.3159 (3)	0.39546 (18)	0.1190 (13)
C17	0.17231 (17)	0.1174 (3)	0.48514 (17)	0.0927 (9)
C18	0.23945 (17)	−0.0643 (2)	0.52107 (17)	0.0885 (8)
H3	0.4934	0.2579	0.5474	0.074*
H5	0.3260	0.0991	0.4443	0.075*
H7	0.4179	0.2485	0.7205	0.078*
H8	0.4264	0.1661	0.3769	0.107*
H9	0.1991	0.0634	0.5869	0.078*
H10	0.2453	−0.0070	0.6924	0.068*
H11A	0.2065	−0.0245	0.8118	0.133*
H11B	0.1608	0.0749	0.7744	0.133*
H11C	0.2287	0.1044	0.8261	0.133*
H12A	0.3633	0.0551	0.7867	0.121*
H12B	0.3776	0.0127	0.7080	0.121*
H12C	0.3417	−0.0712	0.7647	0.121*
H13A	0.5235	0.1345	0.6831	0.139*
H13B	0.5491	0.2402	0.7297	0.139*
H13C	0.5587	0.2437	0.6461	0.139*
H14A	0.4811	0.4230	0.6326	0.143*
H14B	0.4776	0.4289	0.7165	0.143*
H14C	0.4019	0.4327	0.6715	0.143*
H15A	0.5579	0.1368	0.3716	0.241*
H15B	0.5091	0.0391	0.4075	0.241*
H15C	0.5556	0.1252	0.4554	0.241*
H16A	0.5086	0.3502	0.4320	0.178*
H16B	0.4300	0.3577	0.3917	0.178*
H16C	0.5038	0.3186	0.3504	0.178*
H17A	0.1957	0.1137	0.4386	0.139*
H17B	0.1638	0.1965	0.4980	0.139*
H17C	0.1243	0.0772	0.4842	0.139*
H18A	0.1919	−0.1058	0.5215	0.133*
H18B	0.2738	−0.0977	0.5555	0.133*
H18C	0.2618	−0.0688	0.4741	0.133*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0484 (3)	0.0481 (3)	0.0625 (3)	0.0044 (2)	0.0085 (2)	−0.0013 (2)
O1	0.0747 (11)	0.0610 (9)	0.0800 (11)	−0.0046 (8)	0.0145 (9)	−0.0197 (8)
O2	0.0519 (9)	0.0819 (11)	0.0848 (11)	0.0193 (8)	0.0067 (8)	0.0055 (9)
C1	0.0464 (11)	0.0425 (11)	0.0558 (12)	0.0025 (9)	0.0054 (9)	0.0055 (9)
C2	0.0505 (12)	0.0439 (11)	0.0639 (13)	−0.0006 (9)	0.0031 (10)	0.0052 (10)
C3	0.0502 (12)	0.0575 (13)	0.0782 (16)	−0.0057 (10)	0.0128 (11)	0.0092 (12)
C4	0.0691 (15)	0.0575 (13)	0.0650 (14)	−0.0017 (12)	0.0150 (12)	0.0024 (11)
C5	0.0712 (15)	0.0587 (13)	0.0569 (13)	−0.0046 (11)	0.0060 (11)	−0.0030 (11)
C6	0.0535 (12)	0.0475 (12)	0.0619 (13)	0.0008 (9)	0.0032 (10)	0.0030 (10)
C7	0.0547 (13)	0.0687 (15)	0.0715 (15)	−0.0087 (11)	0.0012 (11)	0.0005 (12)
C8	0.102 (2)	0.088 (2)	0.0790 (18)	−0.0102 (16)	0.0381 (16)	−0.0005 (15)
C9	0.0605 (14)	0.0671 (15)	0.0666 (14)	−0.0122 (11)	0.0002 (11)	−0.0019 (11)
C10	0.0567 (13)	0.0530 (12)	0.0602 (13)	−0.0026 (10)	0.0076 (10)	0.0032 (10)
C11	0.095 (2)	0.088 (2)	0.0825 (18)	0.0049 (16)	0.0356 (15)	0.0132 (15)
C12	0.0739 (17)	0.0729 (16)	0.0952 (19)	0.0118 (13)	0.0002 (15)	0.0195 (15)
C13	0.0650 (17)	0.115 (2)	0.098 (2)	0.0022 (16)	−0.0154 (15)	0.0072 (18)
C14	0.094 (2)	0.0752 (18)	0.117 (2)	−0.0159 (15)	−0.0115 (17)	−0.0165 (17)
C15	0.205 (5)	0.113 (3)	0.164 (4)	0.054 (3)	0.118 (4)	0.020 (3)
C16	0.161 (3)	0.106 (3)	0.090 (2)	0.005 (2)	0.043 (2)	0.0300 (19)
C17	0.0732 (17)	0.098 (2)	0.106 (2)	−0.0022 (16)	−0.0216 (16)	0.0008 (18)
C18	0.095 (2)	0.0620 (16)	0.109 (2)	−0.0218 (14)	−0.0021 (17)	0.0015 (15)

Geometric parameters (Å, º)

S1—O2	1.4328 (16)	C10—H10	0.9800
S1—O1	1.4328 (16)	C11—H11A	0.9600
S1—C10	1.796 (2)	C11—H11B	0.9600
S1—C1	1.800 (2)	C11—H11C	0.9600
C1—C2	1.415 (3)	C12—H12A	0.9600
C1—C6	1.417 (3)	C12—H12B	0.9600
C2—C3	1.392 (3)	C12—H12C	0.9600
C2—C7	1.520 (3)	C13—H13A	0.9600
C3—C4	1.385 (3)	C13—H13B	0.9600
C4—C5	1.373 (3)	C13—H13C	0.9600
C4—C8	1.518 (3)	C14—H14A	0.9600
C5—C6	1.383 (3)	C14—H14B	0.9600
C6—C9	1.527 (3)	C14—H14C	0.9600
C7—C13	1.526 (3)	C15—H15A	0.9600
C7—C14	1.527 (4)	C15—H15B	0.9600
C8—C15	1.450 (4)	C15—H15C	0.9600
C8—C16	1.486 (4)	C16—H16A	0.9600
C9—C18	1.522 (3)	C16—H16B	0.9600
C9—C17	1.524 (4)	C16—H16C	0.9600
C10—C12	1.498 (3)	C17—H17A	0.9600
C10—C11	1.521 (3)	C17—H17B	0.9600
C3—H3	0.9300	C17—H17C	0.9600
C5—H5	0.9300	C18—H18A	0.9600
C7—H7	0.9800	C18—H18B	0.9600
C8—H8	0.9800	C18—H18C	0.9600
C9—H9	0.9800
O2—S1—O1	115.76 (10)	C10—C11—H11A	109.5
O2—S1—C10	108.43 (10)	C10—C11—H11B	109.5
O1—S1—C10	107.77 (10)	H11A—C11—H11B	109.5
O2—S1—C1	108.18 (10)	C10—C11—H11C	109.5
O1—S1—C1	110.21 (10)	H11A—C11—H11C	109.5
C10—S1—C1	106.04 (9)	H11B—C11—H11C	109.5
C2—C1—C6	120.47 (19)	C10—C12—H12A	109.5
C3—C2—C1	117.0 (2)	C10—C12—H12B	109.5
C4—C3—C2	123.8 (2)	H12A—C12—H12B	109.5
C5—C4—C3	117.0 (2)	C10—C12—H12C	109.5
C4—C5—C6	123.6 (2)	H12A—C12—H12C	109.5
C5—C6—C1	117.88 (19)	H12B—C12—H12C	109.5
C2—C1—S1	121.28 (16)	C7—C13—H13A	109.5
C6—C1—S1	118.14 (15)	C7—C13—H13B	109.5
C3—C2—C7	116.22 (19)	H13A—C13—H13B	109.5
C1—C2—C7	126.78 (19)	C7—C13—H13C	109.5
C5—C4—C8	122.1 (2)	H13A—C13—H13C	109.5
C3—C4—C8	120.9 (2)	H13B—C13—H13C	109.5
C5—C6—C9	115.9 (2)	C7—C14—H14A	109.5
C1—C6—C9	126.19 (19)	C7—C14—H14B	109.5
C2—C7—C13	111.9 (2)	H14A—C14—H14B	109.5
C2—C7—C14	110.5 (2)	C7—C14—H14C	109.5
C13—C7—C14	110.2 (2)	H14A—C14—H14C	109.5
C15—C8—C16	115.1 (3)	H14B—C14—H14C	109.5
C15—C8—C4	113.0 (3)	C8—C15—H15A	109.5
C16—C8—C4	112.2 (2)	C8—C15—H15B	109.5
C18—C9—C17	110.5 (2)	H15A—C15—H15B	109.5
C18—C9—C6	110.4 (2)	C8—C15—H15C	109.5
C17—C9—C6	111.8 (2)	H15A—C15—H15C	109.5
C12—C10—C11	112.9 (2)	H15B—C15—H15C	109.5
C12—C10—S1	111.89 (16)	C8—C16—H16A	109.5
C11—C10—S1	108.13 (16)	C8—C16—H16B	109.5
C4—C3—H3	118.1	H16A—C16—H16B	109.5
C2—C3—H3	118.1	C8—C16—H16C	109.5
C4—C5—H5	118.2	H16A—C16—H16C	109.5
C6—C5—H5	118.2	H16B—C16—H16C	109.5
C2—C7—H7	108.0	C9—C17—H17A	109.5
C13—C7—H7	108.0	C9—C17—H17B	109.5
C14—C7—H7	108.0	H17A—C17—H17B	109.5
C15—C8—H8	105.1	C9—C17—H17C	109.5
C16—C8—H8	105.1	H17A—C17—H17C	109.5
C4—C8—H8	105.1	H17B—C17—H17C	109.5
C18—C9—H9	108.0	C9—C18—H18A	109.5
C17—C9—H9	108.0	C9—C18—H18B	109.5
C6—C9—H9	108.0	H18A—C18—H18B	109.5
C12—C10—H10	107.9	C9—C18—H18C	109.5
C11—C10—H10	107.9	H18A—C18—H18C	109.5
S1—C10—H10	107.9	H18B—C18—H18C	109.5
O2—S1—C1—C2	139.12 (17)	C2—C1—C6—C9	172.61 (19)
O1—S1—C1—C2	11.64 (19)	S1—C1—C6—C9	−11.3 (3)
C10—S1—C1—C2	−104.74 (17)	C3—C2—C7—C13	−50.2 (3)
O2—S1—C1—C6	−36.94 (18)	C1—C2—C7—C13	129.6 (2)
O1—S1—C1—C6	−164.41 (15)	C3—C2—C7—C14	73.0 (3)
C10—S1—C1—C6	79.21 (17)	C1—C2—C7—C14	−107.2 (3)
C6—C1—C2—C3	5.7 (3)	C5—C4—C8—C15	−107.5 (4)
S1—C1—C2—C3	−170.23 (15)	C3—C4—C8—C15	71.8 (4)
C6—C1—C2—C7	−174.1 (2)	C5—C4—C8—C16	120.3 (3)
S1—C1—C2—C7	9.9 (3)	C3—C4—C8—C16	−60.3 (4)
C1—C2—C3—C4	−1.8 (3)	C5—C6—C9—C18	62.2 (3)
C7—C2—C3—C4	178.0 (2)	C1—C6—C9—C18	−115.3 (3)
C2—C3—C4—C5	−2.9 (3)	C5—C6—C9—C17	−61.3 (3)
C2—C3—C4—C8	177.7 (2)	C1—C6—C9—C17	121.2 (2)
C3—C4—C5—C6	3.9 (3)	O2—S1—C10—C12	173.69 (17)
C8—C4—C5—C6	−176.7 (2)	O1—S1—C10—C12	−60.3 (2)
C4—C5—C6—C1	−0.1 (3)	C1—S1—C10—C12	57.7 (2)
C4—C5—C6—C9	−177.8 (2)	O2—S1—C10—C11	−61.3 (2)
C2—C1—C6—C5	−4.9 (3)	O1—S1—C10—C11	64.69 (19)
S1—C1—C6—C5	171.22 (16)	C1—S1—C10—C11	−177.30 (18)