1,2-Di-2-thienyl-2-hydroxy­ethanone (2,2'-thenoin)

The title compound, C₁₀H₈O₂S₂, is the 2-thienyl symmetric analog of benzoin. 2,2'-Thenoin can be synthesized in good yield utilizing the benzoin condensation reaction (starting with 2-thio­phene­carbox­aldehyde). The crystal structure of 2,2'-thenoin has been determined at room temperature.

Key indicators

• Single-crystal X-ray study
• T = 294 K
• Mean [sigma](C-C) = 0.007 Å
• R factor = 0.048
• wR factor = 0.172
• Data-to-parameter ratio = 9.3

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level A:



THETM_01  Alert A The value of sine(theta_max)/wavelength is less than 0.550
          Calculated sin(theta_max)/wavelength =    0.5207

Author response: Data was collected on several samples and this was the best data set obtained for these small platelike crystals.

 Alert Level C:



REFNR_01  Alert C Ratio of reflections to parameters is < 10 for a
          centrosymmetric structure
          sine(theta)/lambda                0.5207
          Proportion of unique data used    1.0000
          Ratio reflections to parameters   9.3150


 1 Alert Level A = Potentially serious problem

 0 Alert Level B = Potential problem

 1 Alert Level C = Please check

---

Computing details

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SHELXTL-Plus (Sheldrick, 1990); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXL97; software used to prepare material for publication: SHELXL97.

1,2-di-2-thienyl-2-hydroxyethanone

Crystal data

C10H8O2S2	Dx = 1.483 Mg m^−3
Mr = 224.28	Melting point: 117-118° K
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 10.8436 (11) Å	Cell parameters from 3834 reflections
b = 6.0348 (6) Å	θ = 2.0–23.3°
c = 16.336 (2) Å	µ = 0.50 mm^−1
β = 110.001 (2)°	T = 294 K
V = 1004.55 (19) Å^3	Plate, colorless
Z = 4	0.2 × 0.1 × 0.1 mm
F(000) = 464

Data collection

Siemens SMART P3/512CCD diffractometer	1010 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.038
Graphite monochromator	θmax = 21.7°, θmin = 2.0°
ω scans	h = −11→5
3645 measured reflections	k = −6→6
1183 independent reflections	l = −14→17

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.048	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.173	H-atom parameters constrained
S = 1.37	w = 1/[σ^2(Fo^2) + (0.1P)^2] where P = (Fo^2 + 2Fc^2)/3
1183 reflections	(Δ/σ)max = 0.003
127 parameters	Δρmax = 0.33 e Å^−3
0 restraints	Δρmin = −0.35 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
S1	0.15529 (13)	0.2560 (2)	−0.00550 (8)	0.0554 (6)
O1	0.1107 (3)	0.1771 (5)	0.1613 (2)	0.0507 (9)
C1	0.1333 (4)	0.3704 (8)	0.1516 (2)	0.0359 (11)
S2	0.37359 (14)	0.4110 (2)	0.34324 (9)	0.0657 (6)
O2	0.0627 (3)	0.4570 (5)	0.27023 (19)	0.0506 (10)
H2A	0.0193	0.5558	0.2817	0.076*
C2	0.1625 (4)	0.4455 (7)	0.0747 (3)	0.0383 (11)
C3	0.1947 (5)	0.6554 (7)	0.0532 (3)	0.0447 (12)
H3A	0.2051	0.7798	0.0885	0.054*
C4	0.2095 (5)	0.6546 (9)	−0.0292 (3)	0.0607 (15)
H4A	0.2300	0.7799	−0.0551	0.073*
C5	0.1907 (5)	0.4507 (9)	−0.0665 (3)	0.0562 (14)
H5A	0.1969	0.4222	−0.1209	0.067*
C6	0.1352 (4)	0.5454 (7)	0.2201 (3)	0.0365 (11)
H6A	0.0914	0.6798	0.1904	0.044*
C7	0.2735 (4)	0.6009 (7)	0.2743 (3)	0.0376 (11)
C8	0.3400 (4)	0.8026 (7)	0.2791 (3)	0.0438 (12)
H8A	0.3036	0.9289	0.2475	0.053*
C9	0.4696 (6)	0.7881 (10)	0.3385 (4)	0.0699 (16)
H9A	0.5287	0.9054	0.3494	0.084*
C10	0.4995 (5)	0.5929 (10)	0.3771 (4)	0.0702 (16)
H10A	0.5808	0.5594	0.4183	0.084*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0633 (10)	0.0502 (9)	0.0530 (9)	0.0110 (6)	0.0201 (7)	−0.0079 (6)
O1	0.062 (2)	0.037 (2)	0.059 (2)	−0.0017 (17)	0.0270 (17)	0.0004 (15)
C1	0.029 (2)	0.040 (3)	0.037 (2)	0.003 (2)	0.0094 (19)	0.002 (2)
S2	0.0555 (10)	0.0587 (10)	0.0713 (10)	0.0004 (7)	0.0066 (7)	0.0114 (7)
O2	0.050 (2)	0.058 (2)	0.0559 (19)	0.0028 (17)	0.0327 (17)	0.0028 (16)
C2	0.033 (3)	0.046 (3)	0.035 (2)	0.003 (2)	0.0101 (19)	−0.003 (2)
C3	0.067 (3)	0.034 (3)	0.039 (3)	0.003 (2)	0.025 (2)	0.002 (2)
C4	0.080 (4)	0.060 (3)	0.052 (3)	−0.005 (3)	0.035 (3)	0.010 (3)
C5	0.063 (3)	0.070 (4)	0.042 (3)	0.018 (3)	0.027 (3)	0.006 (3)
C6	0.035 (3)	0.038 (3)	0.040 (2)	0.003 (2)	0.018 (2)	0.006 (2)
C7	0.045 (3)	0.040 (3)	0.031 (2)	0.001 (2)	0.018 (2)	−0.0043 (19)
C8	0.040 (3)	0.038 (3)	0.048 (3)	−0.005 (2)	0.010 (2)	0.002 (2)
C9	0.062 (4)	0.060 (4)	0.087 (4)	−0.022 (3)	0.024 (3)	−0.014 (3)
C10	0.042 (3)	0.083 (4)	0.071 (4)	0.002 (3)	0.000 (3)	−0.003 (3)

Geometric parameters (Å, º)

S1—C5	1.668 (5)	C4—C5	1.357 (7)
S1—C2	1.721 (4)	C4—H4A	0.9300
O1—C1	1.214 (5)	C5—H5A	0.9300
C1—C2	1.468 (6)	C6—C7	1.495 (6)
C1—C6	1.533 (6)	C6—H6A	0.9800
S2—C10	1.691 (6)	C7—C8	1.403 (6)
S2—C7	1.710 (4)	C8—C9	1.410 (7)
O2—C6	1.419 (5)	C8—H8A	0.9300
O2—H2A	0.8200	C9—C10	1.324 (7)
C2—C3	1.390 (6)	C9—H9A	0.9300
C3—C4	1.409 (6)	C10—H10A	0.9300
C3—H3A	0.9300
C5—S1—C2	91.6 (2)	O2—C6—C7	112.6 (3)
O1—C1—C2	121.4 (4)	O2—C6—C1	106.9 (3)
O1—C1—C6	121.3 (4)	C7—C6—C1	110.3 (3)
C2—C1—C6	117.3 (4)	O2—C6—H6A	109.0
C10—S2—C7	92.3 (3)	C7—C6—H6A	109.0
C6—O2—H2A	109.5	C1—C6—H6A	109.0
C3—C2—C1	130.1 (4)	C8—C7—C6	128.3 (4)
C3—C2—S1	111.3 (3)	C8—C7—S2	110.2 (3)
C1—C2—S1	118.7 (3)	C6—C7—S2	121.5 (3)
C2—C3—C4	111.0 (4)	C7—C8—C9	110.9 (4)
C2—C3—H3A	124.5	C7—C8—H8A	124.5
C4—C3—H3A	124.5	C9—C8—H8A	124.5
C5—C4—C3	112.6 (4)	C10—C9—C8	114.0 (5)
C5—C4—H4A	123.7	C10—C9—H9A	123.0
C3—C4—H4A	123.7	C8—C9—H9A	123.0
C4—C5—S1	113.6 (3)	C9—C10—S2	112.5 (4)
C4—C5—H5A	123.2	C9—C10—H10A	123.8
S1—C5—H5A	123.2	S2—C10—H10A	123.8