rac-cis-5-Methyl-2,3-diphenyl-1,3-thia­zolidin-4-one

Yennawar, H.P.; Tierney, J.; Silverberg, L.J.

doi:10.1107/S2414314617016625

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 2| Part 11| November 2017| x171662

https://doi.org/10.1107/S2414314617016625

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rac-cis-5-Methyl-2,3-diphenyl-1,3-thiazolidin-4-one

Hemant P. Yennawar,^a John Tierney ^b and Lee J. Silverberg ^c ^*

^aDepartment of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA 16802, USA, ^bPennsylvania State University, Brandywine Campus, 312 Main Building, Brandywine, PA 19063, USA, and ^cPennsylvania State University, Schuylkill Campus, 200 University Drive, Schuylkill Haven, PA 17972, USA
^*Correspondence e-mail: ljs43@psu.edu

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 10 November 2017; accepted 17 November 2017; online 24 November 2017)

In the racemic title compound, C₁₆H₁₅NOS, the thiazolidine ring adopts an envelope conformation, with the S atom as the flap. The dihedral angles between the heterocycle (all atoms) and pendant C– and N-bound benzene rings are 69.75 (14) and 56.56 (11)°, respectively; the aromatic rings are almost orthogonal to each other, with a dihedral angle of 76.04 (14)° between them. In the crystal, molecules are linked by weak C—H⋯O hydrogen bonds to generate [101] chains, with alternating molecules being enantiomers. A weak C—H⋯π interaction is also observed.

Keywords: crystal structure; thiazolidine; envelope pucker; C—H⋯O interactions; weak aromatic interactions.

CCDC reference: 1586333

Structure description

1,3-Thiazolidin-4-ones are of great interest due to their high and diverse biological activity (Jain et al., 2012 ). 5-Methyl-2,3-diaryl-1,3-thiazolidinones are readily available by use of thiolactic acid in the preparation (Patel et al., 1976 ) and show antimicrobial activity (Piscopo et al., 1988 ; Piscopo, Diurno, Gagliardi, Mazzoni, Parrilli & Veneruso, 1989 ; Piscopo, Diurno, Gagliardi, Mazzoni, De Franceso & Veneruso, 1989 ; Piscopo, Diurno, Gagliardi, Mazzoni & Veneruso, 1989 ). However, while the crystal structures of a number of 5-methyl-1,3-thiazolidin-4-ones have been reported (Rang et al., 1997 ; Özturk et al., 2000 ; Dandia et al.; 2006 ; Yalçin et al., 2008 ; Akkurt et al., 2010 , 2011 , 2012 ; Ostapiuk et al., 2012 ; Jiang et al., 2012 ), only two of them were 2,3-diaryl substituted (Özturk et al., 2000; Dandia et al.; 2006).

Herein, we report the synthesis and crystal structure of the cis isomer of rac-5-methyl-2,3-diphenyl-1,3-thiazolidin-4-one. Woolston et al. (1993 ) have reported observing a 3:1 cis:trans ratio in the product, although the method of isolation was not specified. We have previously reported the structure of 2,3-diphenyl-1,3-thiazolidin-4-one (Yennawar et al., 2014 ). The most closely related 5-methyl compound whose crystal structure is known is the 3-(p-chlorophenyl)-2-(8-quinolinyl) compound of Özturk et al. (2000), which displayed an envelope conformation for the thiazolidinone ring.

The title compound (Fig. 1) shows an envelope conformation for the five-membered 1,3-thiazolidin-4-one ring with substitutions at the 2, 3, and 5 ring positions. The phenyl rings at the 2 and 3 positions are close to orthogonal to each other with a dihedral angle of 76.04 (14)° between their planes. In the arbitrarily chosen asymmetric molecule (Fig. 1), C1 and C3 have S and R configurations, respectively, but crystal symmetry generates a racemic mixture. In the extended structure (Fig. 2), the oxygen atom connected to the 4 position of the heterocycle accepts a C—H⋯O interaction (Table 1) arising from a phenyl ring at the 3 position of a symmetry-related enantiomer, resulting in a chain-link in the [101] direction. A weak C—H⋯O interaction (Table 1) is also observed.

Table 1
Hydrogen-bond geometry (Å, °)

Cg3 is the centroid of the C11–C16 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C13—H13⋯O1ⁱ	0.93	2.51	3.366 (3)	154
C3—H3⋯Cg3ⁱⁱ	0.98	2.90	3.783 (3)	151
Symmetry codes: (i) $[x-1, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (ii) $[x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ .

Figure 1
The molecular structure of the title compound, with displacement ellipsoids drawn at the 50% probability level.

Figure 2
Packing diagram of the title compound, with red dotted lines representing C—H⋯O contacts forming chains propagating in the [101] direction.

Synthesis and crystallization

0.05 mol of N-benzylideneaniline and a slight excess of thiolactic acid were dissolved in 60 ml of toluene in a 100 ml round-bottomed flask. The flask was connected to a Dean–Stark trap and condenser and refluxed for 6 h. After cooling, the excess thiolactic acid was neutralized with 5% aqueous NaHCO₃ solution. The toluene layer was removed under vacuum on a rotary evaporator. The product was recrystallized from 95% ethanol solution: m.p. 391–393 K (no literature reports). Crystals for X-ray diffraction studies were grown by slow evaporation from ethanol solution. Only the cis isomer was isolated.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2.

Table 2
Experimental details

Crystal data
Chemical formula	C₁₆H₁₅NOS
M_r	269.35
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	298
a, b, c (Å)	6.2271 (16), 22.531 (6), 9.937 (3)
β (°)	96.545 (4)
V (Å³)	1385.1 (6)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.23
Crystal size (mm)	0.15 × 0.1 × 0.09

Data collection
Diffractometer	Bruker SAINT CCD area detector
Absorption correction	Multi-scan (SADABS; Bruker, 2001 )
T_min, T_max	0.838, 0.9
No. of measured, independent and observed [I > 2σ(I)] reflections	10624, 3360, 2378
R_int	0.037
(sin θ/λ)_max (Å⁻¹)	0.668

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.063, 0.171, 1.04
No. of reflections	3360
No. of parameters	173
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.46, −0.18
Computer programs: SMART and SAINT (Bruker, 2001), SHELXS97 and SHELXL97 (Sheldrick, 2008 ), OLEX2 (Dolomanov et al., 2009 ) and publCIF (Westrip, 2010 ).

Structural data

CCDC reference: 1586333

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2414314617016625/hb4181sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314617016625/hb4181Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314617016625/hb4181Isup3.mol

Supporting information file. DOI: https://doi.org/10.1107/S2414314617016625/hb4181Isup4.cml

checkCIF report

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009) and publCIF (Westrip, 2010).

rac-cis-5-Methyl-2,3-diphenyl-1,3-thiazolidin-4-one top

Crystal data top

C₁₆H₁₅NOS	F(000) = 568
M_r = 269.35	D_x = 1.292 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 6.2271 (16) Å	Cell parameters from 2561 reflections
b = 22.531 (6) Å	θ = 2.3–25.6°
c = 9.937 (3) Å	µ = 0.23 mm⁻¹
β = 96.545 (4)°	T = 298 K
V = 1385.1 (6) Å³	Block, colorless
Z = 4	0.15 × 0.1 × 0.09 mm

Data collection top

Bruker SAINT CCD area detector diffractometer	3360 independent reflections
Radiation source: fine-focus sealed tube	2378 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.037
phi and ω scans	θ_max = 28.3°, θ_min = 1.8°
Absorption correction: multi-scan (SADABS; Bruker, 2001)	h = −8→7
T_min = 0.838, T_max = 0.9	k = −30→29
10624 measured reflections	l = −12→13

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)] = 0.063	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.171	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + (0.0811P)² + 0.3983P] where P = (F_o² + 2F_c²)/3
3360 reflections	(Δ/σ)_max = 0.001
173 parameters	Δρ_max = 0.46 e Å⁻³
0 restraints	Δρ_min = −0.18 e Å⁻³

Special details top

Experimental. The data collection nominally covered a full sphere of reciprocal space by a combination of 4 sets of ω scans each set at different φ and/or 2θ angles and each scan (30 s exposure) covering -0.300° degrees in ω. The crystal to detector distance was 5.82 cm.

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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	0.41425 (13)	0.39324 (4)	1.01291 (7)	0.0782 (3)
O1	0.7411 (3)	0.29432 (8)	0.80393 (16)	0.0588 (5)
N1	0.4230 (3)	0.34551 (7)	0.77525 (17)	0.0393 (4)
C1	0.2685 (4)	0.37863 (10)	0.8464 (2)	0.0476 (5)
H1	0.1414	0.3540	0.8557	0.057*
C2	0.5992 (3)	0.32204 (10)	0.8504 (2)	0.0440 (5)
C3	0.5912 (4)	0.33075 (12)	1.0016 (2)	0.0568 (6)
H3	0.5222	0.2958	1.0365	0.068*
C4	0.8088 (5)	0.33802 (15)	1.0804 (3)	0.0754 (8)
H4A	0.8720	0.3747	1.0556	0.113*
H4B	0.9003	0.3056	1.0608	0.113*
H4C	0.7939	0.3384	1.1755	0.113*
C5	0.1991 (4)	0.43677 (10)	0.7778 (2)	0.0490 (6)
C6	−0.0051 (5)	0.45857 (14)	0.7878 (4)	0.0784 (9)
H6	−0.1011	0.4371	0.8341	0.094*
C7	−0.0674 (6)	0.51299 (16)	0.7282 (5)	0.0978 (12)
H7	−0.2034	0.5285	0.7374	0.117*
C8	0.0701 (6)	0.54313 (13)	0.6571 (4)	0.0914 (11)
H8	0.0259	0.5785	0.6144	0.110*
C9	0.2736 (6)	0.52196 (13)	0.6475 (4)	0.0880 (10)
H9	0.3688	0.5433	0.6005	0.106*
C10	0.3364 (5)	0.46888 (11)	0.7080 (3)	0.0674 (7)
H10	0.4748	0.4545	0.7012	0.081*
C11	0.3725 (3)	0.33221 (8)	0.6344 (2)	0.0364 (4)
C12	0.1711 (3)	0.31056 (9)	0.5866 (2)	0.0461 (5)
H12	0.0676	0.3043	0.6456	0.055*
C13	0.1239 (4)	0.29816 (10)	0.4495 (3)	0.0549 (6)
H13	−0.0110	0.2830	0.4171	0.066*
C14	0.2734 (5)	0.30799 (11)	0.3619 (2)	0.0587 (7)
H14	0.2396	0.3002	0.2700	0.070*
C15	0.4750 (5)	0.32947 (11)	0.4101 (3)	0.0589 (6)
H15	0.5777	0.3356	0.3505	0.071*
C16	0.5252 (4)	0.34184 (10)	0.5455 (2)	0.0471 (5)
H16	0.6610	0.3566	0.5774	0.057*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0871 (6)	0.1043 (6)	0.0412 (4)	0.0397 (4)	−0.0008 (3)	−0.0177 (3)
O1	0.0519 (10)	0.0811 (12)	0.0429 (9)	0.0258 (8)	0.0034 (7)	0.0011 (8)
N1	0.0373 (9)	0.0469 (9)	0.0335 (9)	0.0062 (7)	0.0036 (7)	−0.0016 (7)
C1	0.0421 (12)	0.0592 (13)	0.0418 (12)	0.0086 (10)	0.0067 (9)	−0.0020 (10)
C2	0.0423 (12)	0.0532 (12)	0.0357 (11)	0.0045 (9)	0.0017 (9)	0.0013 (9)
C3	0.0554 (15)	0.0754 (16)	0.0396 (12)	0.0111 (12)	0.0050 (11)	0.0025 (11)
C4	0.0681 (18)	0.114 (2)	0.0408 (14)	0.0151 (16)	−0.0070 (13)	−0.0096 (14)
C5	0.0447 (12)	0.0516 (13)	0.0492 (13)	0.0081 (10)	−0.0018 (10)	−0.0094 (10)
C6	0.0573 (17)	0.0719 (18)	0.106 (3)	0.0172 (14)	0.0090 (16)	−0.0056 (17)
C7	0.071 (2)	0.077 (2)	0.140 (4)	0.0350 (18)	−0.011 (2)	−0.007 (2)
C8	0.102 (3)	0.0477 (15)	0.116 (3)	0.0148 (17)	−0.024 (2)	−0.0010 (16)
C9	0.104 (3)	0.0518 (16)	0.108 (3)	0.0031 (16)	0.010 (2)	0.0053 (16)
C10	0.0656 (17)	0.0515 (14)	0.085 (2)	0.0066 (12)	0.0094 (15)	0.0011 (13)
C11	0.0397 (11)	0.0332 (9)	0.0355 (10)	0.0045 (8)	0.0005 (8)	0.0008 (8)
C12	0.0404 (12)	0.0484 (12)	0.0484 (13)	0.0003 (9)	−0.0005 (10)	0.0058 (9)
C13	0.0519 (14)	0.0490 (12)	0.0580 (15)	−0.0020 (10)	−0.0183 (12)	−0.0003 (11)
C14	0.0752 (18)	0.0578 (14)	0.0395 (12)	0.0074 (12)	−0.0096 (12)	−0.0077 (10)
C15	0.0683 (17)	0.0684 (15)	0.0415 (13)	0.0031 (12)	0.0130 (12)	−0.0035 (11)
C16	0.0452 (12)	0.0560 (13)	0.0396 (11)	−0.0043 (10)	0.0031 (10)	−0.0019 (10)

Geometric parameters (Å, º) top

S1—C1	1.824 (2)	C7—H7	0.9300
S1—C3	1.799 (3)	C7—C8	1.354 (5)
O1—C2	1.216 (3)	C8—H8	0.9300
N1—C1	1.461 (3)	C8—C9	1.367 (5)
N1—C2	1.362 (3)	C9—H9	0.9300
N1—C11	1.431 (3)	C9—C10	1.375 (4)
C1—H1	0.9800	C10—H10	0.9300
C1—C5	1.517 (3)	C11—C12	1.379 (3)
C2—C3	1.521 (3)	C11—C16	1.387 (3)
C3—H3	0.9800	C12—H12	0.9300
C3—C4	1.495 (4)	C12—C13	1.389 (3)
C4—H4A	0.9600	C13—H13	0.9300
C4—H4B	0.9600	C13—C14	1.363 (4)
C4—H4C	0.9600	C14—H14	0.9300
C5—C6	1.377 (3)	C14—C15	1.379 (4)
C5—C10	1.367 (4)	C15—H15	0.9300
C6—H6	0.9300	C15—C16	1.375 (3)
C6—C7	1.397 (5)	C16—H16	0.9300

C3—S1—C1	92.68 (11)	C6—C7—H7	120.0
C2—N1—C1	117.80 (17)	C8—C7—C6	120.0 (3)
C2—N1—C11	121.92 (17)	C8—C7—H7	120.0
C11—N1—C1	119.78 (16)	C7—C8—H8	119.7
S1—C1—H1	109.9	C7—C8—C9	120.5 (3)
N1—C1—S1	104.13 (14)	C9—C8—H8	119.7
N1—C1—H1	109.9	C8—C9—H9	120.2
N1—C1—C5	113.16 (18)	C8—C9—C10	119.5 (3)
C5—C1—S1	109.79 (16)	C10—C9—H9	120.2
C5—C1—H1	109.9	C5—C10—C9	121.2 (3)
O1—C2—N1	124.5 (2)	C5—C10—H10	119.4
O1—C2—C3	123.3 (2)	C9—C10—H10	119.4
N1—C2—C3	112.13 (19)	C12—C11—N1	120.07 (18)
S1—C3—H3	108.1	C12—C11—C16	119.9 (2)
C2—C3—S1	104.59 (16)	C16—C11—N1	120.02 (19)
C2—C3—H3	108.1	C11—C12—H12	120.3
C4—C3—S1	114.0 (2)	C11—C12—C13	119.4 (2)
C4—C3—C2	113.7 (2)	C13—C12—H12	120.3
C4—C3—H3	108.1	C12—C13—H13	119.7
C3—C4—H4A	109.5	C14—C13—C12	120.7 (2)
C3—C4—H4B	109.5	C14—C13—H13	119.7
C3—C4—H4C	109.5	C13—C14—H14	120.1
H4A—C4—H4B	109.5	C13—C14—C15	119.8 (2)
H4A—C4—H4C	109.5	C15—C14—H14	120.1
H4B—C4—H4C	109.5	C14—C15—H15	119.8
C6—C5—C1	119.6 (2)	C16—C15—C14	120.5 (2)
C10—C5—C1	121.5 (2)	C16—C15—H15	119.8
C10—C5—C6	118.9 (2)	C11—C16—H16	120.1
C5—C6—H6	120.1	C15—C16—C11	119.7 (2)
C5—C6—C7	119.8 (3)	C15—C16—H16	120.1
C7—C6—H6	120.1

S1—C1—C5—C6	−94.9 (3)	C2—N1—C11—C12	125.9 (2)
S1—C1—C5—C10	83.8 (3)	C2—N1—C11—C16	−54.9 (3)
O1—C2—C3—S1	160.9 (2)	C3—S1—C1—N1	−24.32 (17)
O1—C2—C3—C4	35.9 (4)	C3—S1—C1—C5	−145.76 (17)
N1—C1—C5—C6	149.2 (2)	C5—C6—C7—C8	2.2 (5)
N1—C1—C5—C10	−32.1 (3)	C6—C5—C10—C9	−0.4 (4)
N1—C2—C3—S1	−23.0 (2)	C6—C7—C8—C9	−2.7 (6)
N1—C2—C3—C4	−148.0 (2)	C7—C8—C9—C10	1.6 (6)
N1—C11—C12—C13	179.64 (18)	C8—C9—C10—C5	−0.1 (5)
N1—C11—C16—C15	−179.4 (2)	C10—C5—C6—C7	−0.6 (4)
C1—S1—C3—C2	26.91 (18)	C11—N1—C1—S1	−172.77 (15)
C1—S1—C3—C4	151.7 (2)	C11—N1—C1—C5	−53.6 (3)
C1—N1—C2—O1	−178.9 (2)	C11—N1—C2—O1	9.2 (3)
C1—N1—C2—C3	5.0 (3)	C11—N1—C2—C3	−166.80 (19)
C1—N1—C11—C12	−45.7 (3)	C11—C12—C13—C14	−1.0 (3)
C1—N1—C11—C16	133.4 (2)	C12—C11—C16—C15	−0.3 (3)
C1—C5—C6—C7	178.1 (3)	C12—C13—C14—C15	1.2 (4)
C1—C5—C10—C9	−179.1 (3)	C13—C14—C15—C16	−0.9 (4)
C2—N1—C1—S1	15.2 (2)	C14—C15—C16—C11	0.5 (4)
C2—N1—C1—C5	134.4 (2)	C16—C11—C12—C13	0.5 (3)

Hydrogen-bond geometry (Å, º) top

Cg3 is the centroid of the C11–C16 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C13—H13···O1ⁱ	0.93	2.51	3.366 (3)	154
C3—H3···Cg3ⁱⁱ	0.98	2.90	3.783 (3)	151

Symmetry codes: (i) x−1, −y+1/2, z−1/2; (ii) x, −y+1/2, z+1/2.

Funding information

We thank Penn State Schuylkill for financial support and National Science Foundation (grant No. CHEM-0131112) for the X-ray diffractometer.

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