1-[(4,5-Dimethyl­cyclo­hexa-1,4-dien-1-yl)sulfon­yl]-4-methyl­benzene

Gray, R.H.; Fronczek, F.R.; Vicente, M.G.H.

doi:10.1107/S1600536808021260

organic compounds

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ISSN: 2056-9890

Volume 64| Part 9| September 2008| Page o1669

doi:10.1107/S1600536808021260

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1-[(4,5-Dimethylcyclohexa-1,4-dien-1-yl)sulfonyl]-4-methylbenzene

Ryan H. Gray,^a Frank R. Fronczek ^a and M. Graça H. Vicente ^a ^*

^aDepartment of Chemistry, Louisiana State University, Baton Rouge, LA 70803-1804, USA
^*Correspondence e-mail: ffroncz@lsu.edu

(Received 30 June 2008; accepted 9 July 2008; online 6 August 2008)

In the title molecule, C₁₅H₁₈O₂S, the dimethylcyclohexadiene unit is slightly non-planar, having a folded conformation with the two double-bond planes forming a dihedral angle of 3.9 (6)°. Methyl groups of the dimethylcyclohexadiene ring tilt away from each other, forming internal C—C—C(Me) angles approximately 11° greater than the exterior angles.

Related literature

For related literature, see: Filatov et al. (2007 ); Glidewell et al. (2001 ); Loudet & Burgess (2007 ); Ogura et al. (2001 ); Tanui et al. (2008 ); Ongayi (2005 ); Pomarico (2009 ).

Experimental

Crystal data

C₁₅H₁₈O₂S
M_r = 262.35
Monoclinic, P 2₁ /c
a = 14.1607 (10) Å
b = 7.5766 (5) Å
c = 12.6923 (10) Å
β = 101.658 (5)°
V = 1333.66 (17) Å³
Z = 4
Cu Kα radiation
μ = 2.08 mm⁻¹
T = 90 K
0.37 × 0.29 × 0.21 mm

Data collection

Bruker Kappa APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2008 ) T_min = 0.513, T_max = 0.669
8185 measured reflections
2414 independent reflections
2388 reflections with I > 2σ(I)
R_int = 0.017

Refinement

R[F² > 2σ(F²)] = 0.031
wR(F²) = 0.079
S = 1.02
2414 reflections
167 parameters
H-atom parameters constrained
Δρ_max = 0.39 e Å⁻³
Δρ_min = −0.35 e Å⁻³

Data collection: APEX2 (Bruker, 2006 ); cell refinement: APEX2; data reduction: APEX2; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808021260/fl2208sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808021260/fl2208Isup2.hkl

checkCIF report

Comment top

The title compound, synonym 3,4-dimethyl-tosyl-cyclohexadiene, (I) is an important intermediate in the synthesis of 3,4-disubstituted pyrroles and isoindoles (Filatov et al., 2007). In particular, the 4,7-dihydroisoindole obtained in one step from (I) has been used in the total syntheses of tetrabenzoporphyrins (TBP) and tetrabenzocorroles (TBC) for application in cancer therapy by photodynamic therapy (PDT), and in the syntheses of BODIPY-type molecules for cancer imaging and diagnosis. On account of their strong absorptions and fluorescence emissions in the near IR region of the spectrum and their high chemical stability, these compounds have shown promise for the above biomedical applications (Ongayi, 2005; Loudet & Burgess, 2007). Compound (I) was prepared by a Diels-Alder cycloaddition reaction of 2,3-dimethylbutadiene with tosyl-acetylene at 60–70 °C.

Compound (I) contains a sulfonyl center which offsets both the tolyl and the dimethylcyclohexadienyl groups from linearity, with C1—S1—C9 angle 102.96 (6)°. Similarly, a 104.20 (5)° C—S—N angle is found in a related tosyl-pyrrole (Tanui et al., 2008).

The cyclohexadiene ring in (I) is nearly planar, exhibiting a slight fold along the C2···C5 line, which joins the two C—C==C—C planes. Those planes form a dihedral angle of 3.9 (6)°. The cyclohexadiene ring forms a dihedral angle of 85.70 (3)° with the phenyl ring plane. The two methyl groups on adjacent C atoms of the cyclohexadiene ring are bent away from each other, causing the interior C—C—C(Me) angles to be approximately 11° greater than exterior angles. The interior angles are 124.36 (15)° at C3 and 123.76 (15)° at C4, while the exterior angles are 112.90 (14)° at C3 and 113.97 (14)°. The methyl groups also twist out of plane, forming a C7—C3—C4—C8 torsion angle of 2.1 (2)°. These methyl groups have an intramolecular H···H contact 2.08 Å (based on H positions determined with HFIX 137), about 0.3 Å less than their van der Waals radii sum.

The structure of a related tosylate compounds have been reported, i.e. 3,4-dimethylbenzenesulfonyl chloride (Glidewell et al., 2001) and 3,4,4-trimethyldiphenyl sulfone (Ogura et al., 2001). The first, QIBREY, differs in 2 ways: a 3,4-dimethylphenyl rather than a 3,4-dimethylcyclohexadiene and a p-Cl phenyl rather than tolyl on the SO₂ center. QIBREY has very similar cell dimensions (in its P2₁/n setting) to (I), and also similar packing, but the two structures are not isomorphous.

Related literature top

For related literature, see: Filatov et al. (2007); Glidewell et al. (2001); Loudet & Burgess (2007); Ogura et al. (2001); Tanui et al. (2008); Ongayi (2005); Pomarico (2009).

Experimental top

The synthesis of the compound was adapted from Pomarico (2009): To a 50 ml round bottom flask, tosyl-acetylene (MW 180, 1.3305 g, 7.39 mmol) and 832 υl of 2,3-dimethylbutadiene (MW 82.15, d 0.726 g/ml) were dissolved in 25 ml of anhydrous toluene. N₂ was introduced for an inert atmosphere. Reaction tube was stirred at 60–70° C for 72 h. Residue was purified by a silica gel column and eluted with hexane-ethyl acetate (4:1). (I) was obtained in the first band. The desired fractions were covered with Parafilm and punctured to allow solvent evaporation. After 72 h, the most concentrated fraction(s) was driven to super-saturation and formed needle crystals (compound I) in solution. The other fractions yielded a yellow-white solid powder (compound I, impure). Yield: 71% (1.3864 g, 5.27 mmol). Spectroscopic analysis, ¹H NMR (400 MHz, CDCl₃, 299 K): 7.78 (2H, d, CH), 7.37 (2H, d, CH), 6.93 (1H, s, CH), 2.80 (2H, s, CH₂), 2.65 (2H, d, CH₂), 2.39 (3H, s, CH₃), 1.57 (6H, s, CH₃). MS (EI) m/z: 263.1098 (M⁺).

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: APEX2 (Bruker, 2006); data reduction: APEX2 (Bruker, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. Ellipsoids at the 50% level, with H atoms having arbitrary radius.
	Fig. 2. The packing viewed approximately down the symmetry direction. H atoms are not shown.

1-[(4,5-Dimethylcyclohexa-1,4-dien-1-yl)sulfonyl]-4-methylbenzene top

Crystal data top

C₁₅H₁₈O₂S	F(000) = 560
M_r = 262.35	D_x = 1.307 Mg m⁻³
Monoclinic, P2₁/c	Cu Kα radiation, λ = 1.54178 Å
Hall symbol: -P 2ybc	Cell parameters from 6824 reflections
a = 14.1607 (10) Å	θ = 3.1–69.6°
b = 7.5766 (5) Å	µ = 2.08 mm⁻¹
c = 12.6923 (10) Å	T = 90 K
β = 101.658 (5)°	Needle fragment, colourless
V = 1333.66 (17) Å³	0.37 × 0.29 × 0.21 mm
Z = 4

Data collection top

Bruker Kappa APEXII CCD area-detector diffractometer	2414 independent reflections
Radiation source: fine-focus sealed tube	2388 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.017
ϕ and ω scans	θ_max = 70.0°, θ_min = 6.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 2008)	h = −16→17
T_min = 0.513, T_max = 0.669	k = −8→8
8185 measured reflections	l = −14→15

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)] = 0.031	H-atom parameters constrained
wR(F²) = 0.079	w = 1/[σ²(F_o²) + (0.0349P)² + 1.1601P] where P = (F_o² + 2F_c²)/3
S = 1.02	(Δ/σ)_max = 0.001
2414 reflections	Δρ_max = 0.39 e Å⁻³
167 parameters	Δρ_min = −0.35 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0014 (2)

Crystal data top

C₁₅H₁₈O₂S	V = 1333.66 (17) Å³
M_r = 262.35	Z = 4
Monoclinic, P2₁/c	Cu Kα radiation
a = 14.1607 (10) Å	µ = 2.08 mm⁻¹
b = 7.5766 (5) Å	T = 90 K
c = 12.6923 (10) Å	0.37 × 0.29 × 0.21 mm
β = 101.658 (5)°

Data collection top

Bruker Kappa APEXII CCD area-detector diffractometer	2414 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2008)	2388 reflections with I > 2σ(I)
T_min = 0.513, T_max = 0.669	R_int = 0.017
8185 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.031	0 restraints
wR(F²) = 0.079	H-atom parameters constrained
S = 1.02	Δρ_max = 0.39 e Å⁻³
2414 reflections	Δρ_min = −0.35 e Å⁻³
167 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	U_iso*/U_eq
S1	0.72081 (2)	0.65111 (5)	0.77242 (3)	0.01466 (12)
O1	0.77069 (8)	0.81816 (14)	0.78620 (9)	0.0217 (3)
O2	0.69509 (8)	0.57537 (14)	0.66619 (8)	0.0203 (2)
C1	0.78977 (10)	0.4965 (2)	0.85979 (11)	0.0150 (3)
C2	0.84519 (10)	0.5644 (2)	0.96471 (12)	0.0181 (3)
H2A	0.8013	0.6342	1.0001	0.022*
H2B	0.8964	0.6447	0.9507	0.022*
C3	0.89062 (10)	0.4216 (2)	1.04018 (12)	0.0192 (3)
C4	0.88460 (10)	0.2504 (2)	1.01358 (12)	0.0199 (3)
C5	0.83462 (11)	0.1878 (2)	0.90446 (12)	0.0213 (3)
H5A	0.8827	0.1294	0.8695	0.026*
H5B	0.7863	0.0978	0.9137	0.026*
C6	0.78555 (10)	0.3272 (2)	0.83147 (12)	0.0172 (3)
H6	0.7501	0.2946	0.7625	0.021*
C7	0.93992 (11)	0.4914 (2)	1.14845 (12)	0.0258 (4)
H7A	0.8916	0.5402	1.1857	0.039*
H7B	0.9856	0.5841	1.1388	0.039*
H7C	0.9746	0.3951	1.1913	0.039*
C8	0.92390 (13)	0.1033 (3)	1.09036 (14)	0.0301 (4)
H8A	0.9855	0.1401	1.1352	0.045*
H8B	0.9339	−0.0023	1.0494	0.045*
H8C	0.8779	0.0768	1.1364	0.045*
C9	0.61462 (10)	0.67078 (18)	0.82478 (11)	0.0138 (3)
C10	0.53295 (10)	0.57652 (19)	0.77775 (12)	0.0171 (3)
H10	0.5326	0.5072	0.7153	0.021*
C11	0.45159 (10)	0.58476 (19)	0.82322 (12)	0.0185 (3)
H11	0.3950	0.5229	0.7903	0.022*
C12	0.45178 (11)	0.6823 (2)	0.91624 (12)	0.0178 (3)
C13	0.53499 (11)	0.7747 (2)	0.96241 (11)	0.0177 (3)
H13	0.5361	0.8410	1.0262	0.021*
C14	0.61613 (10)	0.77178 (19)	0.91700 (11)	0.0157 (3)
H14	0.6719	0.8375	0.9482	0.019*
C15	0.36432 (12)	0.6882 (2)	0.96662 (13)	0.0248 (4)
H15A	0.3324	0.8029	0.9519	0.037*
H15B	0.3841	0.6716	1.0445	0.037*
H15C	0.3196	0.5940	0.9363	0.037*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.01540 (19)	0.0156 (2)	0.01337 (19)	0.00057 (13)	0.00388 (13)	0.00124 (13)
O1	0.0225 (6)	0.0181 (5)	0.0260 (6)	−0.0034 (4)	0.0087 (4)	0.0027 (4)
O2	0.0232 (5)	0.0250 (6)	0.0128 (5)	0.0045 (4)	0.0039 (4)	0.0005 (4)
C1	0.0121 (6)	0.0188 (7)	0.0144 (7)	0.0010 (6)	0.0034 (5)	0.0008 (6)
C2	0.0149 (7)	0.0216 (8)	0.0172 (7)	0.0000 (6)	0.0018 (6)	−0.0032 (6)
C3	0.0123 (7)	0.0312 (9)	0.0144 (7)	0.0017 (6)	0.0037 (5)	−0.0014 (6)
C4	0.0153 (7)	0.0277 (9)	0.0175 (7)	0.0048 (6)	0.0055 (6)	0.0029 (6)
C5	0.0217 (8)	0.0199 (8)	0.0226 (8)	0.0034 (6)	0.0050 (6)	0.0005 (6)
C6	0.0152 (7)	0.0207 (8)	0.0155 (7)	−0.0004 (6)	0.0030 (6)	−0.0018 (6)
C7	0.0205 (8)	0.0399 (10)	0.0161 (7)	0.0047 (7)	0.0013 (6)	−0.0043 (7)
C8	0.0313 (9)	0.0366 (10)	0.0236 (8)	0.0125 (8)	0.0086 (7)	0.0093 (7)
C9	0.0147 (7)	0.0127 (7)	0.0141 (7)	0.0020 (5)	0.0033 (5)	0.0029 (5)
C10	0.0196 (7)	0.0139 (7)	0.0168 (7)	0.0017 (6)	0.0015 (6)	−0.0002 (6)
C11	0.0156 (7)	0.0143 (7)	0.0244 (8)	−0.0011 (5)	0.0012 (6)	0.0026 (6)
C12	0.0189 (7)	0.0151 (7)	0.0199 (7)	0.0051 (6)	0.0055 (6)	0.0084 (6)
C13	0.0219 (7)	0.0169 (7)	0.0141 (7)	0.0050 (6)	0.0031 (6)	0.0013 (6)
C14	0.0166 (7)	0.0140 (7)	0.0154 (7)	0.0014 (5)	0.0002 (5)	0.0007 (6)
C15	0.0224 (8)	0.0252 (8)	0.0292 (9)	0.0051 (6)	0.0110 (7)	0.0089 (7)

Geometric parameters (Å, º) top

S1—O1	1.4427 (11)	C7—H7C	0.9800
S1—O2	1.4427 (11)	C8—H8A	0.9800
S1—C1	1.7656 (14)	C8—H8B	0.9800
S1—C9	1.7687 (14)	C8—H8C	0.9800
C1—C6	1.331 (2)	C9—C10	1.387 (2)
C1—C2	1.4939 (19)	C9—C14	1.395 (2)
C2—C3	1.501 (2)	C10—C11	1.390 (2)
C2—H2A	0.9900	C10—H10	0.9500
C2—H2B	0.9900	C11—C12	1.392 (2)
C3—C4	1.339 (2)	C11—H11	0.9500
C3—C7	1.506 (2)	C12—C13	1.394 (2)
C4—C5	1.499 (2)	C12—C15	1.505 (2)
C4—C8	1.511 (2)	C13—C14	1.386 (2)
C5—C6	1.482 (2)	C13—H13	0.9500
C5—H5A	0.9900	C14—H14	0.9500
C5—H5B	0.9900	C15—H15A	0.9800
C6—H6	0.9500	C15—H15B	0.9800
C7—H7A	0.9800	C15—H15C	0.9800
C7—H7B	0.9800

O1—S1—O2	119.15 (7)	C3—C7—H7C	109.5
O1—S1—C1	108.10 (7)	H7A—C7—H7C	109.5
O2—S1—C1	109.04 (7)	H7B—C7—H7C	109.5
O1—S1—C9	108.25 (7)	C4—C8—H8A	109.5
O2—S1—C9	108.14 (7)	C4—C8—H8B	109.5
C1—S1—C9	102.96 (6)	H8A—C8—H8B	109.5
C6—C1—C2	124.03 (13)	C4—C8—H8C	109.5
C6—C1—S1	118.76 (11)	H8A—C8—H8C	109.5
C2—C1—S1	117.11 (11)	H8B—C8—H8C	109.5
C1—C2—C3	113.62 (13)	C10—C9—C14	120.90 (13)
C1—C2—H2A	108.8	C10—C9—S1	119.54 (11)
C3—C2—H2A	108.8	C14—C9—S1	119.43 (11)
C1—C2—H2B	108.8	C9—C10—C11	119.14 (13)
C3—C2—H2B	108.8	C9—C10—H10	120.4
H2A—C2—H2B	107.7	C11—C10—H10	120.4
C4—C3—C2	122.71 (13)	C10—C11—C12	121.07 (14)
C4—C3—C7	124.36 (15)	C10—C11—H11	119.5
C2—C3—C7	112.90 (14)	C12—C11—H11	119.5
C3—C4—C5	122.24 (14)	C11—C12—C13	118.66 (14)
C3—C4—C8	123.76 (15)	C11—C12—C15	121.03 (14)
C5—C4—C8	113.97 (14)	C13—C12—C15	120.31 (14)
C6—C5—C4	115.24 (13)	C14—C13—C12	121.22 (14)
C6—C5—H5A	108.5	C14—C13—H13	119.4
C4—C5—H5A	108.5	C12—C13—H13	119.4
C6—C5—H5B	108.5	C13—C14—C9	118.98 (13)
C4—C5—H5B	108.5	C13—C14—H14	120.5
H5A—C5—H5B	107.5	C9—C14—H14	120.5
C1—C6—C5	121.90 (14)	C12—C15—H15A	109.5
C1—C6—H6	119.0	C12—C15—H15B	109.5
C5—C6—H6	119.0	H15A—C15—H15B	109.5
C3—C7—H7A	109.5	C12—C15—H15C	109.5
C3—C7—H7B	109.5	H15A—C15—H15C	109.5
H7A—C7—H7B	109.5	H15B—C15—H15C	109.5

O1—S1—C1—C6	−150.24 (12)	C4—C5—C6—C1	3.0 (2)
O2—S1—C1—C6	−19.33 (14)	O1—S1—C9—C10	147.20 (11)
C9—S1—C1—C6	95.35 (13)	O2—S1—C9—C10	16.82 (13)
O1—S1—C1—C2	33.22 (12)	C1—S1—C9—C10	−98.50 (12)
O2—S1—C1—C2	164.13 (10)	O1—S1—C9—C14	−36.97 (13)
C9—S1—C1—C2	−81.20 (12)	O2—S1—C9—C14	−167.34 (11)
C6—C1—C2—C3	−4.3 (2)	C1—S1—C9—C14	77.34 (12)
S1—C1—C2—C3	172.03 (10)	C14—C9—C10—C11	0.5 (2)
C1—C2—C3—C4	2.4 (2)	S1—C9—C10—C11	176.30 (11)
C1—C2—C3—C7	−175.74 (12)	C9—C10—C11—C12	−1.6 (2)
C2—C3—C4—C5	2.1 (2)	C10—C11—C12—C13	1.1 (2)
C7—C3—C4—C5	−179.99 (14)	C10—C11—C12—C15	−178.78 (13)
C2—C3—C4—C8	−175.78 (14)	C11—C12—C13—C14	0.5 (2)
C7—C3—C4—C8	2.1 (2)	C15—C12—C13—C14	−179.66 (13)
C3—C4—C5—C6	−4.9 (2)	C12—C13—C14—C9	−1.5 (2)
C8—C4—C5—C6	173.25 (13)	C10—C9—C14—C13	1.0 (2)
C2—C1—C6—C5	1.6 (2)	S1—C9—C14—C13	−174.79 (11)
S1—C1—C6—C5	−174.69 (11)

Experimental details

Crystal data
Chemical formula	C₁₅H₁₈O₂S
M_r	262.35
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	90
a, b, c (Å)	14.1607 (10), 7.5766 (5), 12.6923 (10)
β (°)	101.658 (5)
V (Å³)	1333.66 (17)
Z	4
Radiation type	Cu Kα
µ (mm⁻¹)	2.08
Crystal size (mm)	0.37 × 0.29 × 0.21

Data collection
Diffractometer	Bruker Kappa APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2008)
T_min, T_max	0.513, 0.669
No. of measured, independent and observed [I > 2σ(I)] reflections	8185, 2414, 2388
R_int	0.017
(sin θ/λ)_max (Å⁻¹)	0.609

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.031, 0.079, 1.02
No. of reflections	2414
No. of parameters	167
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.39, −0.35

Computer programs: APEX2 (Bruker, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), SHELXTL (Sheldrick, 2008).

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