4-Methyl-2,4,6-triphenyl-4H-thio­pyran

Rahmani, H.; Pirelahi, H.; Ng, S.W.

doi:10.1107/S1600536809005911

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 65| Part 3| March 2009| Page o603

doi:10.1107/S1600536809005911

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4-Methyl-2,4,6-triphenyl-4H-thiopyran

Hossein Rahmani,^a Hooshang Pirelahi ^b and Seik Weng Ng ^c ^*

^aInstitute of Chemical Industries, Iranian Research Organization for Science and Technology, PO Box 15815-358, Tehran, Iran, ^bDepartment of Chemistry, College of Science, University of Tehran, PO Box 13145-143, Tehran, Iran, and ^cDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
^*Correspondence e-mail: seikweng@um.edu.my

(Received 18 February 2009; accepted 19 February 2009; online 25 February 2009)

The six-membered thiopyran ring in the title compound, C₂₄H₂₀S, adopts a flattened boat conformation, with the S atom displaced by 0.273 (2) Å and the 3-methylene C atom by 0.294 (3) Å from the plane of the other four sp²-hydridized C atoms. The methyl group on the methylene carbon lies in a axial position with the phenyl equatorial.

Related literature

2,4,4,6-Tetraaryl- or 4-alkyl-2,4,6-triaryl-4H-thiopyrans undergo UV-induced isomerization to form aryl-migrated 2H-thiopyrans; for a discussion of the photoisomerization mechanism, see: Pirelahi et al. (2004 ); Pirelahi & Rahmani (1997 ). 4-Methyl-2,4,6-triphenyl-4H-thiopyran does not react in the solid state, but in solution is converted to 4-methyl-2,3,6-triphenyl-2H-thiopyran; see: Mori & Maeda (1991 ). For the synthesis, see: Suld & Price (1962 ).

Experimental

Crystal data

C₂₄H₂₀S
M_r = 340.46
Monoclinic, C c
a = 9.8737 (2) Å
b = 22.5282 (4) Å
c = 9.2288 (2) Å
β = 118.987 (1)°
V = 1795.67 (6) Å³
Z = 4
Mo Kα radiation
μ = 0.18 mm⁻¹
T = 115 K
0.35 × 0.20 × 0.10 mm

Data collection

Bruker SMART APEX diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.917, T_max = 0.982
8464 measured reflections
3883 independent reflections
3698 reflections with I > σ(I)
R_int = 0.024

Refinement

R[F² > 2σ(F²)] = 0.029
wR(F²) = 0.072
S = 1.03
3883 reflections
227 parameters
2 restraints
H-atom parameters constrained
Δρ_max = 0.28 e Å⁻³
Δρ_min = −0.18 e Å⁻³
Absolute structure: Flack (1983 ), 1825 Friedel pairs
Flack parameter: 0.00 (5)

Data collection: APEX2 (Bruker, 2008 ); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001 ); software used to prepare material for publication: publCIF (Westrip, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809005911/sj2578sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809005911/sj2578Isup2.hkl

checkCIF report

Related literature top

2,4,4,6-Tetraaryl- or 4-alkyl-2,4,6-triaryl-4H-thiopyrans undergo UV-induced isomerization to form aryl-migrated 2H-thiopyrans; for a discussion of the photoisomerization mechanism, see: Pirelahi et al. (2004); Pirelahi & Rahmani (1997). 4-Methyl-2,4,6-triphenyl-4H-thiopyran does not react in the solid state, but in solution is converted to 4-methyl-2,3,6-triphenyl-2H-thiopyran; see: Mori & Maeda (1991). For the synthesis, see: Suld & Price (1962).

Experimental top

The compound was synthesized by the reaction of methyl magnesium bromide and 2,4,6-triphenylthiopyrylium perchlorate in dry ether under an argon atmosphere according to a reported method (Suld & Price, 1962). The product was isolated by TLC on neutral alumina (petroleum ether 40–60 °C) and purified by recrystalization from ethanol.

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2009).

Figures top

Fig. 1. Thermal ellisoid plot (Barbour, 2001) of C₂₄H₂₀S; probability levels are set at 70% and H-atoms are drawn as spheres of arbitrary radius.

4-Methyl-2,4,6-triphenyl-4H-thiopyran top

Crystal data top

C₂₄H₂₀S	F(000) = 720
M_r = 340.46	D_x = 1.259 Mg m⁻³
Monoclinic, Cc	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: C -2yc	Cell parameters from 4067 reflections
a = 9.8737 (2) Å	θ = 2.5–28.0°
b = 22.5282 (4) Å	µ = 0.18 mm⁻¹
c = 9.2288 (2) Å	T = 115 K
β = 118.987 (1)°	Prism, colorless
V = 1795.67 (6) Å³	0.35 × 0.20 × 0.10 mm
Z = 4

Data collection top

Bruker SMART APEX diffractometer	3883 independent reflections
Radiation source: fine-focus sealed tube	3698 reflections with I > σ(I)
Graphite monochromator	R_int = 0.024
ω scans	θ_max = 27.5°, θ_min = 1.8°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −12→12
T_min = 0.917, T_max = 0.982	k = −29→29
8464 measured reflections	l = −11→11

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)] = 0.029	H-atom parameters constrained
wR(F²) = 0.072	w = 1/[σ²(F_o²) + (0.0401P)² + 0.2571P] where P = (F_o² + 2F_c²)/3
S = 1.03	(Δ/σ)_max = 0.001
3883 reflections	Δρ_max = 0.28 e Å⁻³
227 parameters	Δρ_min = −0.18 e Å⁻³
2 restraints	Absolute structure: Flack (1983), 1825 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.00 (5)

Crystal data top

C₂₄H₂₀S	V = 1795.67 (6) Å³
M_r = 340.46	Z = 4
Monoclinic, Cc	Mo Kα radiation
a = 9.8737 (2) Å	µ = 0.18 mm⁻¹
b = 22.5282 (4) Å	T = 115 K
c = 9.2288 (2) Å	0.35 × 0.20 × 0.10 mm
β = 118.987 (1)°

Data collection top

Bruker SMART APEX diffractometer	3883 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	3698 reflections with I > σ(I)
T_min = 0.917, T_max = 0.982	R_int = 0.024
8464 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.029	H-atom parameters constrained
wR(F²) = 0.072	Δρ_max = 0.28 e Å⁻³
S = 1.03	Δρ_min = −0.18 e Å⁻³
3883 reflections	Absolute structure: Flack (1983), 1825 Friedel pairs
227 parameters	Absolute structure parameter: 0.00 (5)
2 restraints

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
S1	0.49977 (4)	0.892322 (17)	0.49963 (4)	0.01993 (9)
C1	0.48277 (17)	0.87133 (6)	0.67575 (18)	0.0169 (3)
C2	0.37550 (18)	0.83350 (7)	0.66660 (19)	0.0197 (3)
H2	0.3740	0.8259	0.7671	0.024*
C3	0.25547 (17)	0.80107 (7)	0.51476 (19)	0.0187 (3)
C4	0.22225 (18)	0.83423 (7)	0.35828 (18)	0.0180 (3)
H4	0.1228	0.8283	0.2651	0.022*
C5	0.31709 (16)	0.87086 (6)	0.33675 (17)	0.0156 (3)
C6	0.3178 (2)	0.73921 (7)	0.5054 (2)	0.0252 (4)
H6A	0.3487	0.7178	0.6092	0.038*
H6B	0.4075	0.7437	0.4879	0.038*
H6C	0.2366	0.7168	0.4131	0.038*
C7	0.59735 (17)	0.90088 (7)	0.83149 (19)	0.0174 (3)
C8	0.55816 (18)	0.91435 (7)	0.95401 (19)	0.0210 (3)
H8	0.4585	0.9041	0.9379	0.025*
C9	0.66275 (19)	0.94253 (7)	1.0990 (2)	0.0241 (3)
H9	0.6341	0.9517	1.1810	0.029*
C10	0.8091 (2)	0.95738 (7)	1.1249 (2)	0.0236 (4)
H10	0.8809	0.9766	1.2245	0.028*
C11	0.84996 (18)	0.94407 (7)	1.0045 (2)	0.0237 (3)
H11	0.9503	0.9540	1.0221	0.028*
C12	0.74509 (18)	0.91643 (7)	0.85877 (19)	0.0207 (3)
H12	0.7738	0.9079	0.7765	0.025*
C13	0.10640 (17)	0.79667 (7)	0.52855 (18)	0.0183 (3)
C14	0.0894 (2)	0.75238 (8)	0.6233 (2)	0.0255 (3)
H14	0.1679	0.7231	0.6742	0.031*
C15	−0.0402 (2)	0.75009 (8)	0.6451 (2)	0.0294 (4)
H15	−0.0487	0.7198	0.7118	0.035*
C16	−0.1572 (2)	0.79169 (8)	0.5702 (2)	0.0284 (4)
H16	−0.2465	0.7899	0.5836	0.034*
C17	−0.14174 (19)	0.83609 (8)	0.47516 (19)	0.0257 (4)
H17	−0.2212	0.8649	0.4232	0.031*
C18	−0.01103 (19)	0.83879 (7)	0.45533 (18)	0.0222 (3)
H18	−0.0016	0.8698	0.3910	0.027*
C19	0.27339 (17)	0.89872 (7)	0.17441 (18)	0.0165 (3)
C20	0.18705 (18)	0.86626 (7)	0.02926 (18)	0.0191 (3)
H20	0.1658	0.8255	0.0359	0.023*
C21	0.13179 (19)	0.89302 (7)	−0.1250 (2)	0.0222 (3)
H21	0.0729	0.8706	−0.2230	0.027*
C22	0.16242 (19)	0.95233 (8)	−0.1358 (2)	0.0238 (4)
H22	0.1232	0.9708	−0.2412	0.029*
C23	0.25068 (19)	0.98482 (7)	0.0078 (2)	0.0242 (3)
H23	0.2722	1.0255	0.0005	0.029*
C24	0.30752 (18)	0.95805 (7)	0.16187 (18)	0.0192 (3)
H24	0.3700	0.9802	0.2594	0.023*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.01477 (16)	0.02749 (19)	0.01650 (17)	−0.00309 (16)	0.00676 (13)	−0.00013 (15)
C1	0.0159 (7)	0.0177 (7)	0.0151 (7)	0.0022 (6)	0.0060 (6)	0.0015 (6)
C2	0.0202 (7)	0.0213 (8)	0.0151 (7)	0.0008 (6)	0.0067 (6)	0.0030 (6)
C3	0.0183 (7)	0.0174 (7)	0.0179 (7)	−0.0021 (6)	0.0069 (6)	0.0014 (5)
C4	0.0177 (7)	0.0189 (7)	0.0146 (7)	−0.0021 (6)	0.0056 (6)	−0.0022 (6)
C5	0.0144 (7)	0.0154 (7)	0.0151 (7)	0.0006 (5)	0.0056 (6)	−0.0027 (5)
C6	0.0260 (9)	0.0207 (8)	0.0305 (9)	0.0010 (7)	0.0150 (7)	0.0016 (7)
C7	0.0144 (7)	0.0168 (7)	0.0159 (7)	0.0014 (6)	0.0032 (6)	0.0022 (5)
C8	0.0149 (7)	0.0237 (8)	0.0219 (8)	−0.0006 (6)	0.0070 (6)	−0.0016 (6)
C9	0.0233 (8)	0.0294 (8)	0.0197 (8)	0.0019 (7)	0.0105 (6)	−0.0021 (6)
C10	0.0203 (8)	0.0216 (8)	0.0206 (8)	−0.0008 (7)	0.0034 (6)	−0.0044 (6)
C11	0.0167 (7)	0.0261 (8)	0.0250 (8)	−0.0027 (6)	0.0075 (6)	−0.0014 (6)
C12	0.0201 (8)	0.0237 (8)	0.0190 (8)	−0.0008 (6)	0.0100 (6)	0.0002 (6)
C13	0.0172 (7)	0.0187 (7)	0.0153 (7)	−0.0034 (6)	0.0048 (6)	−0.0022 (5)
C14	0.0258 (8)	0.0221 (8)	0.0262 (8)	−0.0006 (7)	0.0107 (7)	0.0051 (6)
C15	0.0318 (9)	0.0282 (9)	0.0302 (9)	−0.0090 (7)	0.0167 (8)	0.0027 (7)
C16	0.0208 (8)	0.0378 (10)	0.0267 (9)	−0.0079 (7)	0.0115 (7)	−0.0065 (7)
C17	0.0198 (8)	0.0340 (9)	0.0182 (8)	0.0035 (7)	0.0050 (6)	−0.0011 (6)
C18	0.0246 (8)	0.0228 (8)	0.0166 (8)	−0.0005 (6)	0.0079 (7)	0.0008 (5)
C19	0.0140 (7)	0.0203 (7)	0.0165 (8)	0.0010 (6)	0.0084 (6)	−0.0008 (6)
C20	0.0188 (7)	0.0198 (7)	0.0202 (8)	−0.0007 (6)	0.0106 (6)	−0.0012 (6)
C21	0.0184 (8)	0.0318 (9)	0.0166 (8)	−0.0006 (6)	0.0086 (6)	−0.0019 (6)
C22	0.0195 (8)	0.0346 (9)	0.0197 (8)	0.0068 (7)	0.0113 (7)	0.0079 (7)
C23	0.0262 (8)	0.0216 (8)	0.0314 (9)	−0.0006 (7)	0.0191 (7)	0.0027 (6)
C24	0.0182 (7)	0.0222 (8)	0.0192 (8)	−0.0019 (6)	0.0106 (6)	−0.0027 (6)

Geometric parameters (Å, º) top

S1—C5	1.7661 (14)	C11—H11	0.9500
S1—C1	1.7772 (15)	C12—H12	0.9500
C1—C2	1.330 (2)	C13—C14	1.390 (2)
C1—C7	1.488 (2)	C13—C18	1.393 (2)
C2—C3	1.514 (2)	C14—C15	1.390 (2)
C2—H2	0.9500	C14—H14	0.9500
C3—C4	1.514 (2)	C15—C16	1.384 (3)
C3—C13	1.541 (2)	C15—H15	0.9500
C3—C6	1.543 (2)	C16—C17	1.386 (3)
C4—C5	1.333 (2)	C16—H16	0.9500
C4—H4	0.9500	C17—C18	1.390 (2)
C5—C19	1.483 (2)	C17—H17	0.9500
C6—H6A	0.9800	C18—H18	0.9500
C6—H6B	0.9800	C19—C20	1.396 (2)
C6—H6C	0.9800	C19—C24	1.397 (2)
C7—C8	1.394 (2)	C20—C21	1.391 (2)
C7—C12	1.399 (2)	C20—H20	0.9500
C8—C9	1.386 (2)	C21—C22	1.384 (2)
C8—H8	0.9500	C21—H21	0.9500
C9—C10	1.387 (3)	C22—C23	1.390 (2)
C9—H9	0.9500	C22—H22	0.9500
C10—C11	1.386 (2)	C23—C24	1.388 (2)
C10—H10	0.9500	C23—H23	0.9500
C11—C12	1.386 (2)	C24—H24	0.9500

C5—S1—C1	101.27 (7)	C11—C12—C7	120.71 (15)
C2—C1—C7	123.89 (14)	C11—C12—H12	119.6
C2—C1—S1	122.53 (12)	C7—C12—H12	119.6
C7—C1—S1	113.57 (11)	C14—C13—C18	117.92 (14)
C1—C2—C3	127.59 (14)	C14—C13—C3	120.65 (14)
C1—C2—H2	116.2	C18—C13—C3	121.32 (14)
C3—C2—H2	116.2	C15—C14—C13	121.22 (16)
C4—C3—C2	110.82 (12)	C15—C14—H14	119.4
C4—C3—C13	109.66 (12)	C13—C14—H14	119.4
C2—C3—C13	107.77 (13)	C16—C15—C14	120.43 (16)
C4—C3—C6	107.47 (13)	C16—C15—H15	119.8
C2—C3—C6	109.47 (13)	C14—C15—H15	119.8
C13—C3—C6	111.67 (12)	C15—C16—C17	118.94 (16)
C5—C4—C3	127.18 (13)	C15—C16—H16	120.5
C5—C4—H4	116.4	C17—C16—H16	120.5
C3—C4—H4	116.4	C16—C17—C18	120.56 (16)
C4—C5—C19	122.09 (13)	C16—C17—H17	119.7
C4—C5—S1	122.96 (11)	C18—C17—H17	119.7
C19—C5—S1	114.91 (11)	C17—C18—C13	120.92 (15)
C3—C6—H6A	109.5	C17—C18—H18	119.5
C3—C6—H6B	109.5	C13—C18—H18	119.5
H6A—C6—H6B	109.5	C20—C19—C24	118.78 (14)
C3—C6—H6C	109.5	C20—C19—C5	119.41 (13)
H6A—C6—H6C	109.5	C24—C19—C5	121.68 (13)
H6B—C6—H6C	109.5	C21—C20—C19	120.60 (15)
C8—C7—C12	118.32 (14)	C21—C20—H20	119.7
C8—C7—C1	120.06 (14)	C19—C20—H20	119.7
C12—C7—C1	121.62 (14)	C22—C21—C20	120.09 (15)
C9—C8—C7	120.86 (15)	C22—C21—H21	120.0
C9—C8—H8	119.6	C20—C21—H21	120.0
C7—C8—H8	119.6	C21—C22—C23	119.82 (15)
C8—C9—C10	120.22 (15)	C21—C22—H22	120.1
C8—C9—H9	119.9	C23—C22—H22	120.1
C10—C9—H9	119.9	C24—C23—C22	120.22 (15)
C11—C10—C9	119.59 (15)	C24—C23—H23	119.9
C11—C10—H10	120.2	C22—C23—H23	119.9
C9—C10—H10	120.2	C23—C24—C19	120.44 (14)
C12—C11—C10	120.30 (15)	C23—C24—H24	119.8
C12—C11—H11	119.9	C19—C24—H24	119.8
C10—C11—H11	119.9

C5—S1—C1—C2	17.61 (15)	C4—C3—C13—C14	157.18 (14)
C5—S1—C1—C7	−161.33 (11)	C2—C3—C13—C14	−82.11 (17)
C7—C1—C2—C3	−179.48 (15)	C6—C3—C13—C14	38.2 (2)
S1—C1—C2—C3	1.7 (2)	C4—C3—C13—C18	−26.78 (19)
C1—C2—C3—C4	−24.4 (2)	C2—C3—C13—C18	93.93 (16)
C1—C2—C3—C13	−144.35 (16)	C6—C3—C13—C18	−145.80 (14)
C1—C2—C3—C6	94.01 (19)	C18—C13—C14—C15	−0.2 (2)
C2—C3—C4—C5	26.5 (2)	C3—C13—C14—C15	175.99 (16)
C13—C3—C4—C5	145.30 (15)	C13—C14—C15—C16	1.0 (3)
C6—C3—C4—C5	−93.12 (19)	C14—C15—C16—C17	−0.9 (3)
C3—C4—C5—C19	177.18 (14)	C15—C16—C17—C18	0.0 (3)
C3—C4—C5—S1	−5.5 (2)	C16—C17—C18—C13	0.8 (2)
C1—S1—C5—C4	−15.81 (15)	C14—C13—C18—C17	−0.7 (2)
C1—S1—C5—C19	161.67 (11)	C3—C13—C18—C17	−176.85 (14)
C2—C1—C7—C8	−31.3 (2)	C4—C5—C19—C20	−37.1 (2)
S1—C1—C7—C8	147.59 (12)	S1—C5—C19—C20	145.37 (12)
C2—C1—C7—C12	149.37 (16)	C4—C5—C19—C24	138.58 (16)
S1—C1—C7—C12	−31.71 (19)	S1—C5—C19—C24	−38.92 (19)
C12—C7—C8—C9	0.1 (2)	C24—C19—C20—C21	−2.1 (2)
C1—C7—C8—C9	−179.21 (15)	C5—C19—C20—C21	173.78 (14)
C7—C8—C9—C10	−0.5 (3)	C19—C20—C21—C22	0.1 (2)
C8—C9—C10—C11	0.2 (3)	C20—C21—C22—C23	1.0 (2)
C9—C10—C11—C12	0.4 (3)	C21—C22—C23—C24	−0.3 (2)
C10—C11—C12—C7	−0.8 (3)	C22—C23—C24—C19	−1.7 (2)
C8—C7—C12—C11	0.5 (2)	C20—C19—C24—C23	2.8 (2)
C1—C7—C12—C11	179.82 (15)	C5—C19—C24—C23	−172.93 (14)

Experimental details

Crystal data
Chemical formula	C₂₄H₂₀S
M_r	340.46
Crystal system, space group	Monoclinic, Cc
Temperature (K)	115
a, b, c (Å)	9.8737 (2), 22.5282 (4), 9.2288 (2)
β (°)	118.987 (1)
V (Å³)	1795.67 (6)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.18
Crystal size (mm)	0.35 × 0.20 × 0.10

Data collection
Diffractometer	Bruker SMART APEX diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.917, 0.982
No. of measured, independent and observed [I > σ(I)] reflections	8464, 3883, 3698
R_int	0.024
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.029, 0.072, 1.03
No. of reflections	3883
No. of parameters	227
No. of restraints	2
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.28, −0.18
Absolute structure	Flack (1983), 1825 Friedel pairs
Absolute structure parameter	0.00 (5)

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2009).

Acknowledgements

We thank the Iranian Research Organization for Science and Technology and the University of Malaya for supporting this study.

References

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