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2,3-Di­phenyl-2,3,5,6-tetra­hydro-4H-1,3-thia­zin-4-one

aDepartment of Chemistry, Pennsylvania State University, University Park, PA 16802, USA, and bPennsylvania State University, Schuylkill Campus, 200 University Drive, Schuylkill Haven, PA 17972, USA
*Correspondence e-mail: ljs43@psu.edu

(Received 7 November 2013; accepted 6 January 2014; online 15 January 2014)

The six-membered thia­zine ring in the title compound, C16H15NOS, adopts a half-chair conformation, with the S atom forming the back of the chair. The base of the chair has a slight twist reflected in the r.m.s. deviation (0.0756 Å) of those five atoms from the plane defined by them. The phenyl substituents are almost perpendicular to each other [dihedral angle 87.06 (9)°]. In the crystal, mol­ecules are linked into chains parallel to the c axis through C—H⋯O inter­actions.

Related literature

For a review of 1,3-thia­zin-4-ones, see: Ryabukhin et al. (1996[Ryabukhin, Y. I., Korzhavina, O. B. & Suzdalev, K. F. (1996). Adv. Heterocycl. Chem. 66, 131-191.]). For an unsuccessful attempt to make the title compound, see: Surrey et al. (1958[Surrey, A. R., Webb, W. G. & Gesler, R. M. (1958). J. Am. Chem. Soc. 80, 3469-3471.]). For applications of 2,4,6-tripropyl-1,3,5,2,4,6-trioxatri­phospho­rinane-2,4,6-trioxide (T3P) in the synthesis of amide bonds and heterocycles, see: Dunetz et al. (2011[Dunetz, J. R., Xiang, Y., Baldwin, A. & Ringling, J. (2011). Org. Lett. 13, 5048-5051.]); Unsworth et al. (2013[Unsworth, W. P., Kitsiou, C. & Taylor, R. J. K. (2013). Org. Lett. 15, 258-261.]). For the synthesis and structures of related compounds, see: Yennawar et al. (2013[Yennawar, H. P., Silverberg, L. J., Minehan, M. J. & Tierney, J. (2013). Acta Cryst. E69, o1679.]); Yennawar & Silverberg (2013[Yennawar, H. P. & Silverberg, L. J. (2013). Acta Cryst. E69, o1659.]).

[Scheme 1]

Experimental

Crystal data
  • C16H15NOS

  • Mr = 269.35

  • Monoclinic, P 21 /c

  • a = 13.745 (3) Å

  • b = 8.240 (2) Å

  • c = 12.151 (3) Å

  • β = 100.079 (6)°

  • V = 1355.0 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.23 mm−1

  • T = 298 K

  • 0.20 × 0.18 × 0.07 mm

Data collection
  • Bruker SMART APEX CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2001[Bruker (2001). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.956, Tmax = 0.984

  • 12350 measured reflections

  • 3342 independent reflections

  • 2558 reflections with I > 2σ(I)

  • Rint = 0.041

Refinement
  • R[F2 > 2σ(F2)] = 0.061

  • wR(F2) = 0.140

  • S = 1.13

  • 3342 reflections

  • 172 parameters

  • H-atom parameters not refined

  • Δρmax = 0.31 e Å−3

  • Δρmin = −0.18 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C4—H4⋯O1i 0.98 2.33 3.265 (3) 159
Symmetry code: (i) [x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}].

Data collection: SMART (Bruker, 2001[Bruker (2001). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2001[Bruker (2001). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT (Bruker, 2001[Bruker (2001). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]).

Supporting information


Comment top

The 2,3,5,6-tetrahydro-1,3-thiazin-4-ones are an important class of heterocycle with substantial biological activity (Ryabukhin et al., 1996). Surrey has reported that the title compound could not be prepared by condensation of N-benzylideneaniline with 3-mercaptopropionic acid in refluxing benzene, unlike when the imine was N-alkyl (Surrey et al., 1958). Here we report the synthesis of the novel title molecule by condensation of N-benzylideneaniline with 3-mercaptopropionic acid in the presence of 2,4,6-tripropyl-1,3,5,2,4,6-trioxatriphosphorinane-2,4,6-trioxide (T3P) and pyridine (Dunetz et al., 2011). We have recently reported the syntheses of 2-(3-nitrophenyl)-3-phenyl-2,3-dihydro-4H-1,3-benzothiazin-4-one (Yennawar et al., 2013) and 6,7-diphenyl-5-thia-7-azaspiro[2.6]nonan-8-one (Yennawar & Silverberg, 2013) by this method. A similar preparation of a 2,3-dialkyl-2,3-dihydro-1,3-benzothiazin-4-one was also recently reported (Unsworth et al., 2013).

Related literature top

For a review of 1,3-thiazin-4-ones, see: Ryabukhin et al. (1996). For an unsuccessful attempt to make the title compound, see: Surrey et al. (1958). For applications of 2,4,6-tripropyl-1,3,5,2,4,6-trioxatriphosphorinane-2,4,6-trioxide (T3P) in the synthesis of amide bonds and heterocycles, see: Dunetz et al. (2011); Unsworth et al. (2013). For the synthesis and structures of related compounds, see: Yennawar et al. (2013); Yennawar & Silverberg (2013).

Experimental top

A two-necked 25 ml roundbottom flask was oven-dried, cooled under N2, and charged with a stir bar and N-benzylideneaniline (1.087 g, 6 mmol). Tetrahydrofuran (2.3 ml) was added, the solid dissolved, and the solution was stirred. Pyridine (1.95 ml, 24 mmol) was added and then 3-mercaptopropionic acid (0.523 ml, 6 mmol) was added. Finally, 2,4,6-tripropyl-1,3,5,2,4,6-trioxatriphosphorinane-2,4,6-trioxide in 2-methyltetrahydrofuran (50 weight percent; 7.1 ml, 12 mmol) was added. The reaction was stirred at room temperature for 23 h, then poured into a separatory funnel with dichloromethane (20 ml). The mixture was washed with water (10 ml). The aqueous was then extracted twice with dichloromethane (10 ml each). The organics were combined and washed with saturated sodium bicarbonate (10 ml) and saturated sodium chloride (10 ml). The organic was dried over sodium sulfate, concentrated in vacuo and chromatographed on 30 g flash silica gel, eluting with mixtures of ethyl acetate and hexanes (20% to 100% ethyl acetate). The product eluted with 60–100% EtOAc/hexanes and was concentrated in vacuo to pale yellow viscous oil (1.3720 g). Recrystallization from ethanol gave white solid (0.7669 g, 47.5%). m.p.: 95–96.5°C. Rf = 0.32 (50% EtOAc/hexanes). Crystals for X-ray crystallography were grown by dissolving the solid in ethanol, adding some water, and then allowing slow evaporation to occur. After crystals grew, the supernatant was decanted off, and the crystals were rinsed twice with 95% ethanol.

Refinement top

The C–bound H atoms were geometrically placed with C—H = 0.93–0.97 Å, and refined as riding with Uiso(H) = 1.2Ueq(C).

Structure description top

The 2,3,5,6-tetrahydro-1,3-thiazin-4-ones are an important class of heterocycle with substantial biological activity (Ryabukhin et al., 1996). Surrey has reported that the title compound could not be prepared by condensation of N-benzylideneaniline with 3-mercaptopropionic acid in refluxing benzene, unlike when the imine was N-alkyl (Surrey et al., 1958). Here we report the synthesis of the novel title molecule by condensation of N-benzylideneaniline with 3-mercaptopropionic acid in the presence of 2,4,6-tripropyl-1,3,5,2,4,6-trioxatriphosphorinane-2,4,6-trioxide (T3P) and pyridine (Dunetz et al., 2011). We have recently reported the syntheses of 2-(3-nitrophenyl)-3-phenyl-2,3-dihydro-4H-1,3-benzothiazin-4-one (Yennawar et al., 2013) and 6,7-diphenyl-5-thia-7-azaspiro[2.6]nonan-8-one (Yennawar & Silverberg, 2013) by this method. A similar preparation of a 2,3-dialkyl-2,3-dihydro-1,3-benzothiazin-4-one was also recently reported (Unsworth et al., 2013).

For a review of 1,3-thiazin-4-ones, see: Ryabukhin et al. (1996). For an unsuccessful attempt to make the title compound, see: Surrey et al. (1958). For applications of 2,4,6-tripropyl-1,3,5,2,4,6-trioxatriphosphorinane-2,4,6-trioxide (T3P) in the synthesis of amide bonds and heterocycles, see: Dunetz et al. (2011); Unsworth et al. (2013). For the synthesis and structures of related compounds, see: Yennawar et al. (2013); Yennawar & Silverberg (2013).

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: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures top
[Figure 1] Fig. 1. ORTEP view of the title comound. Displacement ellipsoids were drawn at the 50% probability level.
[Figure 2] Fig. 2. Crystal packing.
2,3-Diphenyl-2,3,5,6-tetrahydro-4H-1,3-thiazin-4-one top
Crystal data top
C16H15NOSF(000) = 568
Mr = 269.35Dx = 1.320 Mg m3
Monoclinic, P21/cMelting point: 369 K
Hall symbol: -P 2ybcMo Kα radiation, λ = 0.71073 Å
a = 13.745 (3) ÅCell parameters from 2176 reflections
b = 8.240 (2) Åθ = 2.9–24.6°
c = 12.151 (3) ŵ = 0.23 mm1
β = 100.079 (6)°T = 298 K
V = 1355.0 (6) Å3Block, colorless
Z = 40.20 × 0.18 × 0.07 mm
Data collection top
Bruker SMART APEX CCD
diffractometer
3342 independent reflections
Radiation source: fine-focus sealed tube2558 reflections with I > 2σ(I)
Parallel, graphite monochromatorRint = 0.041
Detector resolution: 8.34 pixels mm-1θmax = 28.3°, θmin = 2.9°
φ and ω scansh = 1818
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
k = 1010
Tmin = 0.956, Tmax = 0.984l = 1615
12350 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.061Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.140H-atom parameters not refined
S = 1.13 w = 1/[σ2(Fo2) + (0.0575P)2 + 0.2756P]
where P = (Fo2 + 2Fc2)/3
3342 reflections(Δ/σ)max = 0.001
172 parametersΔρmax = 0.31 e Å3
0 restraintsΔρmin = 0.18 e Å3
Crystal data top
C16H15NOSV = 1355.0 (6) Å3
Mr = 269.35Z = 4
Monoclinic, P21/cMo Kα radiation
a = 13.745 (3) ŵ = 0.23 mm1
b = 8.240 (2) ÅT = 298 K
c = 12.151 (3) Å0.20 × 0.18 × 0.07 mm
β = 100.079 (6)°
Data collection top
Bruker SMART APEX CCD
diffractometer
3342 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
2558 reflections with I > 2σ(I)
Tmin = 0.956, Tmax = 0.984Rint = 0.041
12350 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0610 restraints
wR(F2) = 0.140H-atom parameters not refined
S = 1.13Δρmax = 0.31 e Å3
3342 reflectionsΔρmin = 0.18 e Å3
172 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
xyzUiso*/Ueq
C10.70658 (15)0.2133 (3)0.70023 (17)0.0367 (5)
C20.59588 (16)0.2058 (3)0.66146 (19)0.0443 (5)
H2A0.57050.31580.66000.053*
H2B0.58380.16640.58510.053*
C30.53595 (16)0.1031 (3)0.72800 (19)0.0468 (6)
H3A0.54810.01100.71620.056*
H3B0.46610.12390.70350.056*
C40.69656 (14)0.0797 (2)0.88595 (16)0.0306 (4)
H40.73130.12140.95770.037*
C50.70157 (14)0.1039 (2)0.89528 (16)0.0317 (4)
C60.73750 (16)0.2034 (3)0.8207 (2)0.0433 (5)
H60.75840.15870.75850.052*
C70.74288 (18)0.3710 (3)0.8377 (3)0.0586 (7)
H70.76700.43760.78680.070*
C80.71254 (19)0.4369 (3)0.9293 (3)0.0625 (8)
H80.71660.54840.94110.075*
C90.6762 (2)0.3388 (3)1.0037 (2)0.0606 (7)
H90.65500.38401.06550.073*
C100.67093 (18)0.1745 (3)0.98732 (19)0.0475 (6)
H100.64650.10911.03860.057*
C110.85580 (14)0.1465 (3)0.82879 (18)0.0367 (5)
C120.91089 (17)0.0689 (3)0.7593 (2)0.0535 (6)
H120.87960.01990.69360.064*
C131.0121 (2)0.0647 (4)0.7881 (3)0.0781 (9)
H131.04920.01180.74200.094*
C141.0589 (2)0.1379 (5)0.8843 (3)0.0823 (11)
H141.12740.13560.90280.099*
C151.0044 (2)0.2145 (4)0.9531 (3)0.0749 (9)
H151.03620.26371.01850.090*
C160.90219 (17)0.2192 (3)0.9258 (2)0.0524 (6)
H160.86530.27110.97270.063*
N10.74904 (11)0.14718 (19)0.79997 (13)0.0316 (4)
O10.75623 (12)0.2813 (2)0.64049 (14)0.0575 (5)
S10.57039 (4)0.15171 (7)0.87256 (5)0.04271 (18)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0418 (11)0.0387 (11)0.0300 (10)0.0028 (9)0.0075 (9)0.0028 (9)
C20.0424 (12)0.0530 (13)0.0352 (12)0.0065 (10)0.0006 (9)0.0050 (10)
C30.0327 (11)0.0543 (13)0.0510 (14)0.0016 (10)0.0008 (10)0.0004 (11)
C40.0321 (10)0.0345 (10)0.0260 (9)0.0025 (8)0.0073 (8)0.0002 (8)
C50.0271 (9)0.0337 (10)0.0324 (10)0.0023 (7)0.0001 (8)0.0023 (8)
C60.0378 (11)0.0417 (12)0.0525 (14)0.0020 (9)0.0138 (10)0.0028 (10)
C70.0433 (13)0.0410 (13)0.094 (2)0.0012 (10)0.0176 (13)0.0159 (14)
C80.0509 (14)0.0345 (12)0.096 (2)0.0045 (11)0.0033 (14)0.0155 (14)
C90.0751 (19)0.0483 (15)0.0552 (16)0.0134 (13)0.0024 (14)0.0187 (13)
C100.0596 (15)0.0456 (13)0.0380 (12)0.0084 (11)0.0105 (11)0.0057 (10)
C110.0304 (10)0.0388 (11)0.0416 (12)0.0023 (8)0.0079 (8)0.0100 (9)
C120.0406 (13)0.0620 (16)0.0622 (16)0.0002 (11)0.0210 (12)0.0015 (13)
C130.0433 (15)0.101 (2)0.096 (2)0.0096 (15)0.0308 (16)0.016 (2)
C140.0302 (13)0.116 (3)0.100 (3)0.0001 (15)0.0103 (16)0.032 (2)
C150.0471 (16)0.099 (2)0.071 (2)0.0182 (16)0.0107 (14)0.0139 (17)
C160.0413 (13)0.0632 (16)0.0502 (14)0.0058 (11)0.0010 (11)0.0036 (12)
N10.0297 (8)0.0362 (9)0.0296 (8)0.0012 (7)0.0073 (6)0.0046 (7)
O10.0549 (10)0.0746 (12)0.0447 (10)0.0011 (9)0.0138 (8)0.0237 (9)
S10.0376 (3)0.0476 (3)0.0466 (3)0.0076 (2)0.0176 (2)0.0004 (3)
Geometric parameters (Å, º) top
C1—O11.217 (2)C7—H70.9300
C1—N11.363 (3)C8—C91.370 (4)
C1—C21.513 (3)C8—H80.9300
C2—C31.511 (3)C9—C101.368 (3)
C2—H2A0.9700C9—H90.9300
C2—H2B0.9700C10—H100.9300
C3—S11.783 (2)C11—C161.376 (3)
C3—H3A0.9700C11—C121.385 (3)
C3—H3B0.9700C11—N11.448 (2)
C4—N11.478 (2)C12—C131.374 (4)
C4—C51.518 (3)C12—H120.9300
C4—S11.813 (2)C13—C141.371 (5)
C4—H40.9800C13—H130.9300
C5—C61.377 (3)C14—C151.370 (5)
C5—C101.390 (3)C14—H140.9300
C6—C71.396 (3)C15—C161.387 (4)
C6—H60.9300C15—H150.9300
C7—C81.368 (4)C16—H160.9300
O1—C1—N1121.12 (19)C7—C8—H8120.0
O1—C1—C2118.13 (19)C9—C8—H8120.0
N1—C1—C2120.75 (18)C10—C9—C8120.3 (2)
C3—C2—C1117.96 (18)C10—C9—H9119.9
C3—C2—H2A107.8C8—C9—H9119.9
C1—C2—H2A107.8C9—C10—C5121.0 (2)
C3—C2—H2B107.8C9—C10—H10119.5
C1—C2—H2B107.8C5—C10—H10119.5
H2A—C2—H2B107.2C16—C11—C12120.2 (2)
C2—C3—S1109.00 (16)C16—C11—N1120.3 (2)
C2—C3—H3A109.9C12—C11—N1119.6 (2)
S1—C3—H3A109.9C13—C12—C11119.6 (3)
C2—C3—H3B109.9C13—C12—H12120.2
S1—C3—H3B109.9C11—C12—H12120.2
H3A—C3—H3B108.3C14—C13—C12120.6 (3)
N1—C4—C5113.97 (16)C14—C13—H13119.7
N1—C4—S1113.02 (13)C12—C13—H13119.7
C5—C4—S1111.29 (13)C15—C14—C13119.9 (3)
N1—C4—H4105.9C15—C14—H14120.1
C5—C4—H4105.9C13—C14—H14120.1
S1—C4—H4105.9C14—C15—C16120.4 (3)
C6—C5—C10118.4 (2)C14—C15—H15119.8
C6—C5—C4124.14 (19)C16—C15—H15119.8
C10—C5—C4117.46 (18)C11—C16—C15119.4 (3)
C5—C6—C7120.5 (2)C11—C16—H16120.3
C5—C6—H6119.8C15—C16—H16120.3
C7—C6—H6119.8C1—N1—C11118.34 (16)
C8—C7—C6119.8 (2)C1—N1—C4126.35 (16)
C8—C7—H7120.1C11—N1—C4115.27 (15)
C6—C7—H7120.1C3—S1—C495.72 (10)
C7—C8—C9120.0 (2)
O1—C1—C2—C3172.2 (2)C13—C14—C15—C160.3 (5)
N1—C1—C2—C38.5 (3)C12—C11—C16—C150.2 (4)
C1—C2—C3—S149.0 (2)N1—C11—C16—C15178.7 (2)
N1—C4—C5—C69.7 (3)C14—C15—C16—C110.1 (4)
S1—C4—C5—C6119.51 (19)O1—C1—N1—C115.6 (3)
N1—C4—C5—C10167.98 (17)C2—C1—N1—C11175.19 (19)
S1—C4—C5—C1062.8 (2)O1—C1—N1—C4172.0 (2)
C10—C5—C6—C70.1 (3)C2—C1—N1—C47.2 (3)
C4—C5—C6—C7177.6 (2)C16—C11—N1—C1122.7 (2)
C5—C6—C7—C80.2 (4)C12—C11—N1—C158.8 (3)
C6—C7—C8—C90.5 (4)C16—C11—N1—C455.1 (3)
C7—C8—C9—C100.6 (4)C12—C11—N1—C4123.4 (2)
C8—C9—C10—C50.3 (4)C5—C4—N1—C1108.3 (2)
C6—C5—C10—C90.0 (3)S1—C4—N1—C120.1 (2)
C4—C5—C10—C9177.9 (2)C5—C4—N1—C1174.1 (2)
C16—C11—C12—C130.2 (4)S1—C4—N1—C11157.54 (14)
N1—C11—C12—C13178.4 (2)C2—C3—S1—C464.60 (17)
C11—C12—C13—C140.6 (4)N1—C4—S1—C351.31 (16)
C12—C13—C14—C150.7 (5)C5—C4—S1—C378.43 (16)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C4—H4···O1i0.982.333.265 (3)159
Symmetry code: (i) x, y+1/2, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C4—H4···O1i0.982.333.265 (3)159
Symmetry code: (i) x, y+1/2, z+1/2.
 

Acknowledgements

We acknowledge NSF funding (CHEM-0131112) for the X-ray diffractometer. We also express gratitude to Euticals for gift of T3P in 2-methyl­tetra­hydro­furan.

References

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