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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 68| Part 9| September 2012| Page o2644
doi:10.1107/S1600536812034137

(Z)-2-[Meth­­oxy(phen­yl)methyl­­idene]-3,4,5-tri­methyl-2,3-di­hydro-1,3-thia­zole

Biplab Maji,a Herbert Mayra and Peter Mayera*

aLudwig-Maximilians-Universität, Department, Butenandtstrasse 5–13, 81377 München, Germany
*Correspondence e-mail: pemay@cup.uni-muenchen.de

(Received 20 July 2012; accepted 31 July 2012; online 4 August 2012)

In the title compound, C14H17NOS, the plane defined by the bridging methyl­ene C atom and its three substituents makes dihedral angles of 14.37 (8)° with the heterocycle and 26.17 (8)° with the phenyl ring, while the dihedral angle between the heterocycle and the phenyl ring is 36.29 (7)°. In the crystal, mol­ecules are linked by C—H⋯π contacts.

Related literature

For chemical background, see: Ukai et al. (1943[Ukai, T., Tanaka, R. & Dokawa, T. (1943). J. Pharm. Soc. Jpn, 63, 296-300.]); Enders et al. (2007[Enders, D., Niemeier, O. & Henseler, A. (2007). Chem. Rev. 107, 5606-5655.]); Biju et al. (2011[Biju, A. T., Kuhl, N. & Glorius, F. (2011). Acc. Chem. Res. 44, 1182-1195.]); Breslow (1958[Breslow, R. (1958). J. Am. Chem. Soc. 80, 3719-3726.]). For a related structure, see: Reisser et al. (2003[Reisser, M., Maier, A. & Maas, G. (2003). Eur. J. Org. Chem. pp. 2071-2079.]).

[Scheme 1]

Experimental

Crystal data

  • C14H17NOS

  • Mr = 247.36

  • Monoclinic, P 21 /c

  • a = 15.9660 (7) Å

  • b = 6.8902 (3) Å

  • c = 12.1520 (6) Å

  • β = 103.381 (5)°

  • V = 1300.54 (10) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.23 mm−1

  • T = 173 K

  • 0.35 × 0.25 × 0.17 mm
Data collection

  • Oxford Diffraction Xcalibur diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, England.]) Tmin = 0.953, Tmax = 1.000

  • 9041 measured reflections

  • 2637 independent reflections

  • 2023 reflections with I > 2σ(I)

  • Rint = 0.029
Refinement

  • R[F2 > 2σ(F2)] = 0.036

  • wR(F2) = 0.104

  • S = 1.08

  • 2637 reflections

  • 158 parameters

  • H-atom parameters constrained

  • Δρmax = 0.29 e Å−3

  • Δρmin = −0.19 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C5–C10 ring.
D—H⋯A D—H H⋯A D⋯A D—H⋯A
C8—H8⋯Cg1i 0.95 2.83 3.6324 (16) 142
C13—H13B⋯Cg1ii 0.98 2.74 3.5657 (15) 143
Symmetry codes: (i) [-x, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) x, y+1, z.

Data collection: CrysAlis PRO (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SIR99 (Altomare et al., 1999[Altomare, A., Burla, M. C., Camalli, M., Cascarano, G. L., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G. & Spagna, R. (1999). J. Appl. Cryst. 32, 115-119.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812034137/su2484sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812034137/su2484Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812034137/su2484Isup3.cml

checkCIF report


Comment top

Thiazolium ions (Ukai et al., 1943) are known to catalyze benzoin condensations of aldehydes (Enders et al., 2007; Biju et al., 2011) in presence of a base. An acyl anion equivalent, the so-called Breslow intermediate (Breslow, 1958) was proposed to be the key intermediate of these transformations. To understand the structure of these intermediates we now report the X-ray analysis of the O-methyl-protected Breslow intermediate derived from 3,4,5-trimethylthiazolium ion and benzaldehyde.

The molecular structure of the title compound is shown in Fig. 1. The exocyclic double bond has a length of 1.349 (2) Å which is comparable to that observed for a related structure [1.353 Å; Reisser et al., 2003]. The endocyclic double bond length is 1.330 (2) Å [1.332 Å; Reisser et al., 2003]. The angle sum around the methylene carbon atom, C4, amounts to 360° resulting in a trigonal planar environment of the methylene atom. However, this mean plane (C4/O1/C3/C5) is not coplanar with either the plane of the heterocycle (S1/N1/C1-C3) or the plane of the phenyl ring (C5-C10). The corresponding dihedral angles are 14.37 (8)° and 26.17 (8)°, respectively. The dihedral angle between the heterocycle and the phenyl ring is 36.29 (7)°.

In the crystal, molecules are linked via C–H···π contacts (Table 1 and Fig. 2).

Related literature top

For chemical background, see: Ukai et al. (1943); Enders et al. (2007); Biju et al. (2011); Breslow (1958). For a related structure, see: Reisser et al. (2003).

Experimental top

A solution of 2-(methoxy(phenyl)methyl)-3,4,5-trimethylthiazolium trifluoromethanesulfonate (397 mg, 1.00 mmol) in THF (6 ml) was added dropwise to a stirred suspension of NaH (36 mg, 1.5 mmol) in dry THF (5 ml) at -20 °C under nitrogen, and the reaction mixture was allowed to stir for 36 h in the dark. After warming to room temperature, the solvent was removed under vacuum, and the residue was suspended in dry toluene (20 ml) and filtered through a celite pad under nitrogen. Then the solvent was evaporated to give 205 mg (0.829 mmol, 83%) of the title compound as 2:1 mixture of Z:E isomers. Crystals of the title compound suitable for X-ray diffraction analysis were grown by slow evaporation of a solution in n-pentane under nitrogen.

Refinement top

The C-bound H atoms were included in calculated positions and treated as riding atoms: C-H = 0.95 and 0.98 Å for CH and CH3 -atoms, respectively, with Uiso(H) = k × Ueq(C), where k = 1.5 for CH3 H atoms and = 1.2 for other H atoms. The methyl groups were allowed to rotate along the C–X bonds (X = C, O, N) to best fit the experimental electron density.

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell refinement: CrysAlis PRO (Oxford Diffraction, 2009); data reduction: CrysAlis PRO (Oxford Diffraction, 2009); program(s) used to solve structure: SIR99 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title molecule, with atom labelling. Displacement ellipsoids are drawn at 50% probability level.
[Figure 2] Fig. 2. The crystal packing of the title compound viewed along the b axis.
(Z)-2-[Methoxy(phenyl)methylidene]-3,4,5-trimethyl-2,3-dihydro- 1,3-thiazole top
Crystal data top
C14H17NOSF(000) = 528
Mr = 247.36Dx = 1.263 (1) Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 4082 reflections
a = 15.9660 (7) Åθ = 4.5–26.2°
b = 6.8902 (3) ŵ = 0.23 mm−1
c = 12.1520 (6) ÅT = 173 K
β = 103.381 (5)°Block, yellow
V = 1300.54 (10) Å30.35 × 0.25 × 0.17 mm
Z = 4
Data collection top
Oxford Diffraction Xcalibur
diffractometer		2637 independent reflections
Radiation source: fine-focus sealed tube2023 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.029
Detector resolution: 15.9809 pixels mm-1θmax = 26.3°, θmin = 4.5°
ω scansh = −19→18
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2009)		k = −7→8
Tmin = 0.953, Tmax = 1.000l = −13→15
9041 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)] = 0.036Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.104H-atom parameters constrained
S = 1.08 w = 1/[σ2(Fo2) + (0.0601P)2]
where P = (Fo2 + 2Fc2)/3
2637 reflections(Δ/σ)max < 0.001
158 parametersΔρmax = 0.29 e Å−3
0 restraintsΔρmin = −0.19 e Å−3
Crystal data top
C14H17NOSV = 1300.54 (10) Å3
Mr = 247.36Z = 4
Monoclinic, P21/cMo Kα radiation
a = 15.9660 (7) ŵ = 0.23 mm−1
b = 6.8902 (3) ÅT = 173 K
c = 12.1520 (6) Å0.35 × 0.25 × 0.17 mm
β = 103.381 (5)°
Data collection top
Oxford Diffraction Xcalibur
diffractometer		2637 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2009)		2023 reflections with I > 2σ(I)
Tmin = 0.953, Tmax = 1.000Rint = 0.029
9041 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0360 restraints
wR(F2) = 0.104H-atom parameters constrained
S = 1.08Δρmax = 0.29 e Å−3
2637 reflectionsΔρmin = −0.19 e Å−3
158 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 > 2σ(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
S10.39851 (3)0.51962 (7)0.17439 (4)0.03514 (16)
O10.33687 (7)0.25112 (16)0.31574 (8)0.0298 (3)
N10.23682 (8)0.61091 (19)0.10461 (10)0.0248 (3)
C10.36863 (11)0.7059 (3)0.07369 (13)0.0314 (4)
C20.28401 (11)0.7353 (2)0.04813 (12)0.0282 (4)
C30.28957 (10)0.4751 (2)0.17383 (12)0.0229 (3)
C40.26767 (9)0.3291 (2)0.23561 (12)0.0227 (3)
C50.18289 (9)0.2433 (2)0.22982 (12)0.0213 (3)
C60.11844 (10)0.2412 (2)0.12977 (12)0.0246 (3)
H60.12860.30310.06420.030*
C70.04027 (10)0.1508 (2)0.12457 (13)0.0271 (4)
H7−0.00270.15250.05590.033*
C80.02412 (10)0.0577 (2)0.21848 (14)0.0297 (4)
H8−0.0297−0.00400.21490.036*
C90.08769 (11)0.0561 (2)0.31769 (13)0.0294 (4)
H90.0775−0.00840.38240.035*
C100.16563 (10)0.1466 (2)0.32384 (12)0.0252 (3)
H100.20830.14350.39280.030*
C110.43748 (12)0.8120 (3)0.03234 (16)0.0437 (5)
H11A0.41100.9126−0.02160.065*
H11B0.46890.7204−0.00490.065*
H11C0.47750.87250.09660.065*
C120.23515 (12)0.8848 (3)−0.03065 (15)0.0425 (5)
H12A0.21600.98810.01330.064*
H12B0.18490.8242−0.08060.064*
H12C0.27250.9401−0.07620.064*
C130.15990 (10)0.6830 (2)0.13668 (13)0.0288 (4)
H13A0.10860.62960.08530.043*
H13B0.15850.82500.13190.043*
H13C0.16100.64290.21440.043*
C140.35969 (12)0.0583 (3)0.28898 (16)0.0424 (5)
H14A0.3103−0.02820.28430.064*
H14B0.40820.01210.34820.064*
H14C0.37620.05940.21620.064*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0248 (2)0.0356 (3)0.0462 (3)−0.00279 (18)0.01062 (19)0.00815 (19)
O10.0287 (6)0.0251 (7)0.0319 (6)0.0017 (5)−0.0005 (5)0.0051 (5)
N10.0293 (7)0.0198 (7)0.0265 (7)0.0006 (6)0.0094 (5)0.0047 (5)
C10.0376 (10)0.0279 (9)0.0311 (9)−0.0085 (8)0.0129 (7)−0.0003 (7)
C20.0385 (10)0.0235 (9)0.0241 (8)−0.0066 (7)0.0105 (7)0.0006 (6)
C30.0223 (8)0.0220 (8)0.0247 (8)0.0002 (6)0.0061 (6)−0.0015 (6)
C40.0235 (8)0.0203 (8)0.0237 (8)0.0030 (6)0.0040 (6)0.0014 (6)
C50.0249 (8)0.0150 (8)0.0247 (8)0.0017 (6)0.0074 (6)−0.0015 (6)
C60.0311 (9)0.0179 (8)0.0261 (8)0.0042 (7)0.0091 (6)0.0005 (6)
C70.0268 (8)0.0195 (8)0.0326 (9)0.0032 (7)0.0019 (7)−0.0051 (6)
C80.0269 (9)0.0205 (9)0.0437 (10)−0.0023 (7)0.0119 (7)−0.0036 (7)
C90.0379 (10)0.0217 (9)0.0324 (9)−0.0027 (7)0.0161 (7)0.0013 (7)
C100.0311 (9)0.0211 (8)0.0237 (8)−0.0003 (7)0.0070 (6)0.0000 (6)
C110.0455 (11)0.0442 (12)0.0455 (10)−0.0170 (9)0.0192 (9)0.0017 (9)
C120.0496 (11)0.0405 (12)0.0375 (10)−0.0028 (9)0.0103 (8)0.0157 (8)
C130.0321 (9)0.0225 (9)0.0330 (9)0.0036 (7)0.0101 (7)0.0026 (7)
C140.0347 (10)0.0302 (11)0.0598 (12)0.0092 (8)0.0059 (9)0.0059 (9)
Geometric parameters (Å, º) top
S1—C11.7614 (17)C8—C91.385 (2)
S1—C31.7646 (16)C8—H80.9500
O1—C41.3999 (17)C9—C101.378 (2)
O1—C141.435 (2)C9—H90.9500
N1—C31.402 (2)C10—H100.9500
N1—C21.4186 (19)C11—H11A0.9800
N1—C131.4589 (19)C11—H11B0.9800
C1—C21.330 (2)C11—H11C0.9800
C1—C111.500 (2)C12—H12A0.9800
C2—C121.497 (2)C12—H12B0.9800
C3—C41.349 (2)C12—H12C0.9800
C4—C51.464 (2)C13—H13A0.9800
C5—C61.399 (2)C13—H13B0.9800
C5—C101.404 (2)C13—H13C0.9800
C6—C71.383 (2)C14—H14A0.9800
C6—H60.9500C14—H14B0.9800
C7—C81.384 (2)C14—H14C0.9800
C7—H70.9500
C1—S1—C390.90 (8)C10—C9—H9119.5
C4—O1—C14113.50 (12)C8—C9—H9119.5
C3—N1—C2112.39 (13)C9—C10—C5121.03 (14)
C3—N1—C13119.55 (12)C9—C10—H10119.5
C2—N1—C13119.85 (13)C5—C10—H10119.5
C2—C1—C11129.13 (16)C1—C11—H11A109.5
C2—C1—S1111.73 (12)C1—C11—H11B109.5
C11—C1—S1119.09 (13)H11A—C11—H11B109.5
C1—C2—N1114.82 (15)C1—C11—H11C109.5
C1—C2—C12127.22 (15)H11A—C11—H11C109.5
N1—C2—C12117.94 (15)H11B—C11—H11C109.5
C4—C3—N1129.40 (14)C2—C12—H12A109.5
C4—C3—S1120.65 (12)C2—C12—H12B109.5
N1—C3—S1109.95 (11)H12A—C12—H12B109.5
C3—C4—O1114.14 (13)C2—C12—H12C109.5
C3—C4—C5129.08 (13)H12A—C12—H12C109.5
O1—C4—C5116.78 (12)H12B—C12—H12C109.5
C6—C5—C10117.31 (14)N1—C13—H13A109.5
C6—C5—C4122.12 (13)N1—C13—H13B109.5
C10—C5—C4120.40 (13)H13A—C13—H13B109.5
C7—C6—C5121.24 (14)N1—C13—H13C109.5
C7—C6—H6119.4H13A—C13—H13C109.5
C5—C6—H6119.4H13B—C13—H13C109.5
C6—C7—C8120.62 (14)O1—C14—H14A109.5
C6—C7—H7119.7O1—C14—H14B109.5
C8—C7—H7119.7H14A—C14—H14B109.5
C7—C8—C9118.86 (15)O1—C14—H14C109.5
C7—C8—H8120.6H14A—C14—H14C109.5
C9—C8—H8120.6H14B—C14—H14C109.5
C10—C9—C8120.94 (14)
C3—S1—C1—C23.05 (13)S1—C3—C4—O113.63 (19)
C3—S1—C1—C11−179.13 (14)N1—C3—C4—C514.8 (3)
C11—C1—C2—N1−178.57 (16)S1—C3—C4—C5−166.26 (12)
S1—C1—C2—N1−1.02 (18)C14—O1—C4—C3−110.21 (16)
C11—C1—C2—C120.3 (3)C14—O1—C4—C569.70 (17)
S1—C1—C2—C12177.82 (15)C3—C4—C5—C628.4 (2)
C3—N1—C2—C1−2.3 (2)O1—C4—C5—C6−151.44 (14)
C13—N1—C2—C1146.04 (15)C3—C4—C5—C10−156.27 (16)
C3—N1—C2—C12178.72 (14)O1—C4—C5—C1023.8 (2)
C13—N1—C2—C12−32.9 (2)C10—C5—C6—C71.3 (2)
C2—N1—C3—C4−176.49 (15)C4—C5—C6—C7176.69 (14)
C13—N1—C3—C435.0 (2)C5—C6—C7—C8−0.7 (2)
C2—N1—C3—S14.49 (15)C6—C7—C8—C9−0.2 (2)
C13—N1—C3—S1−143.98 (12)C7—C8—C9—C100.6 (2)
C1—S1—C3—C4176.64 (13)C8—C9—C10—C50.0 (2)
C1—S1—C3—N1−4.25 (11)C6—C5—C10—C9−0.9 (2)
N1—C3—C4—O1−165.29 (14)C4—C5—C10—C9−176.45 (14)
Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the C5–C10 ring.
D—H···AD—HH···AD···AD—H···A
C8—H8···Cg1i0.952.833.6324 (16)142
C13—H13B···Cg1ii0.982.743.5657 (15)143
Symmetry codes: (i) −x, y−1/2, −z+1/2; (ii) x, y+1, z.

Experimental details

Crystal data
Chemical formulaC14H17NOS
Mr247.36
Crystal system, space groupMonoclinic, P21/c
Temperature (K)173
a, b, c (Å)15.9660 (7), 6.8902 (3), 12.1520 (6)
β (°) 103.381 (5)
V (Å3)1300.54 (10)
Z4
Radiation typeMo Kα
µ (mm−1)0.23
Crystal size (mm)0.35 × 0.25 × 0.17
Data collection
DiffractometerOxford Diffraction Xcalibur
diffractometer
Absorption correctionMulti-scan
(CrysAlis PRO; Oxford Diffraction, 2009)
Tmin, Tmax0.953, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections		9041, 2637, 2023
Rint0.029
(sin θ/λ)max (Å−1)0.624
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.036, 0.104, 1.08
No. of reflections2637
No. of parameters158
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.29, −0.19

Computer programs: CrysAlis PRO (Oxford Diffraction, 2009), SIR99 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the C5–C10 ring.
D—H···AD—HH···AD···AD—H···A
C8—H8···Cg1i0.952.833.6324 (16)142
C13—H13B···Cg1ii0.982.743.5657 (15)143
Symmetry codes: (i) −x, y−1/2, −z+1/2; (ii) x, y+1, z.
 

Acknowledgements

The authors thank Prof. Thomas M. Klapötke for generous allocation of diffractometer time.

References

First citationAltomare, A., Burla, M. C., Camalli, M., Cascarano, G. L., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G. & Spagna, R. (1999). J. Appl. Cryst. 32, 115–119.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationBiju, A. T., Kuhl, N. & Glorius, F. (2011). Acc. Chem. Res. 44, 1182–1195.  Web of Science CrossRef CAS PubMed Google Scholar
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ISSN: 2056-9890
Volume 68| Part 9| September 2012| Page o2644
doi:10.1107/S1600536812034137
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