3,3,4,4,5,5-Hexafluoro-1,2-bis­{3-methyl-5-[3-(trifluoro­meth­yl)phen­yl]-2-thien­yl}cyclo­pent-1-ene

The title compound, C₂₉H₁₆F₁₂S₂, a photochromic dithienyl­ethene, is a potential material for optical storage. It adopts a photo-active antiparallel conformation in the single crystalline phase. The distance between the two reactive C atoms is 3.624 (8) Å. The mol­ecule has crystallographic twofold rotation symmetry. The dihedral angles between the cyclo­pentene ring and the attached thio­phene and benzene rings are 47.2 (2) and 17.9 (2)°, respectively.

Key indicators

• Single-crystal X-ray study
• T = 295 K
• Mean [sigma](C-C) = 0.006 Å
• R factor = 0.075
• wR factor = 0.145
• Data-to-parameter ratio = 12.4

checkCIF/PLATON results

No syntax errors found



Alert level A
PLAT242_ALERT_2_A Check Low       Ueq as Compared to Neighbors for         C3

Author Response: The cyclopentene composed of C1, C2, C3, C1A and C2A is planar which is the average of two envelope conformations so that the displacement parameters of florine atoms of C2 and C3 are large. The displacement parameters of florine atoms of trifloromethyl are large because of the rotation of C10-C14 Single bond.

PLAT242_ALERT_2_A Check Low       Ueq as Compared to Neighbors for        C14

Author Response: The cyclopentene composed of C1, C2, C3, C1A and C2A is planar which is the average of two envelope conformations so that the displacement parameters of florine atoms of C2 and C3 are large. The displacement parameters of florine atoms of trifloromethyl are large because of the rotation of C10-C14 Single bond.

Alert level B
PLAT242_ALERT_2_B Check Low       Ueq as Compared to Neighbors for         C2

Author Response: The cyclopentene composed of C1, C2, C3, C1A and C2A is planar which is the average of two envelope conformations so that the displacement parameters of florine atoms of C2 and C3 are large. The displacement parameters of florine atoms of trifloromethyl are large because of the rotation of C10-C14 Single bond.

Alert level C
PLAT213_ALERT_2_C Atom F3      has ADP max/min Ratio .............       3.70 prolat
PLAT220_ALERT_2_C Large Non-Solvent    F     Ueq(max)/Ueq(min) ...       2.68 Ratio
PLAT230_ALERT_2_C Hirshfeld Test Diff for    F4     -   C14     ..       5.12 su
PLAT340_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          6

   2 ALERT level A = In general: serious problem
   1 ALERT level B = Potentially serious problem
   4 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   6 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: XSCANS (Bruker, 1997); cell refinement: XSCANS; data reduction: XSCANS; program(s) used to solve structure: SHELXTL (Bruker, 1997); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

3,3,4,4,5,5-Hexafluoro-1,2-bis{3-methyl-5-[3-(trifluoromethyl)phenyl}- 2-thienyl]cyclopent-1-ene

Crystal data

C29H16F12S2	F(000) = 1320
Mr = 656.54	Dx = 1.577 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 37 reflections
a = 20.011 (2) Å	θ = 4.8–12.5°
b = 8.6936 (8) Å	µ = 0.29 mm^−1
c = 16.3481 (16) Å	T = 295 K
β = 103.498 (8)°	Prism, yellow
V = 2765.5 (5) Å^3	0.5 × 0.4 × 0.4 mm
Z = 4

Data collection

Bruker P4 diffractometer	1876 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.028
Graphite monochromator	θmax = 25.0°, θmin = 2.6°
ω scans	h = −1→23
Absorption correction: empirical (using intensity measurements) (North et al., 1968)	k = −10→1
Tmin = 0.843, Tmax = 0.889	l = −19→18
2996 measured reflections	3 standard reflections every 97 reflections
2422 independent reflections	intensity decay: none

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)] = 0.075	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.145	H-atom parameters constrained
S = 1.01	w = 1/[σ^2(Fo^2) + (0.001P)^2 + 13P] where P = (Fo^2 + 2Fc^2)/3
2422 reflections	(Δ/σ)max = 0.001
196 parameters	Δρmax = 0.56 e Å^−3
0 restraints	Δρmin = −0.48 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	0.38674 (6)	1.08574 (13)	0.58465 (7)	0.0694 (3)
F1	0.4928 (2)	1.4229 (4)	0.6099 (2)	0.1144 (12)
F2	0.40109 (18)	1.4168 (4)	0.6513 (3)	0.1323 (14)
F3	0.5443 (4)	1.5833 (6)	0.7316 (3)	0.307 (6)
F4	0.2878 (2)	0.3479 (5)	0.4435 (4)	0.179 (2)
F5	0.2978 (4)	0.3801 (6)	0.3227 (3)	0.233 (3)
F6	0.3843 (2)	0.3753 (4)	0.4253 (3)	0.1250 (12)
C1	0.4842 (2)	1.2295 (4)	0.7086 (2)	0.0601 (10)
C2	0.4683 (3)	1.3908 (5)	0.6771 (3)	0.0762 (13)
C3	0.5000	1.4928 (8)	0.7500	0.122 (4)
C4	0.4670 (2)	1.0995 (5)	0.6516 (2)	0.0595 (10)
C5	0.5084 (2)	0.9765 (5)	0.6420 (2)	0.0587 (10)
C6	0.4728 (2)	0.8730 (5)	0.5801 (3)	0.0640 (11)
H6A	0.4930	0.7842	0.5652	0.077*
C7	0.4068 (2)	0.9134 (5)	0.5443 (2)	0.0612 (10)
C8	0.3548 (2)	0.8310 (5)	0.4808 (2)	0.0624 (10)
C9	0.3626 (2)	0.6754 (5)	0.4659 (3)	0.0675 (11)
H9A	0.4013	0.6231	0.4957	0.081*
C10	0.3136 (2)	0.5982 (6)	0.4072 (3)	0.0713 (12)
C11	0.2567 (3)	0.6720 (7)	0.3621 (3)	0.0830 (14)
H11A	0.2243	0.6193	0.3217	0.100*
C12	0.2478 (3)	0.8249 (7)	0.3770 (3)	0.0878 (15)
H12A	0.2086	0.8750	0.3470	0.105*
C13	0.2943 (2)	0.9036 (6)	0.4340 (3)	0.0716 (12)
H13A	0.2869	1.0072	0.4429	0.086*
C14	0.3219 (3)	0.4310 (7)	0.3949 (4)	0.0998 (18)
C15	0.5817 (2)	0.9549 (5)	0.6877 (3)	0.0737 (12)
H15A	0.6022	1.0534	0.7040	0.110*
H15B	0.6062	0.9042	0.6515	0.110*
H15C	0.5837	0.8932	0.7369	0.110*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0706 (7)	0.0580 (6)	0.0748 (7)	0.0121 (5)	0.0072 (5)	−0.0026 (5)
F1	0.182 (3)	0.0718 (19)	0.098 (2)	−0.001 (2)	0.049 (2)	0.0193 (17)
F2	0.099 (2)	0.072 (2)	0.214 (4)	0.0303 (18)	0.012 (2)	0.013 (2)
F3	0.520 (14)	0.202 (5)	0.130 (4)	−0.258 (7)	−0.064 (6)	0.057 (4)
F4	0.148 (4)	0.086 (3)	0.316 (7)	−0.001 (3)	0.083 (4)	0.008 (4)
F5	0.397 (9)	0.124 (4)	0.115 (3)	0.058 (4)	−0.069 (4)	−0.056 (3)
F6	0.119 (3)	0.085 (2)	0.169 (3)	0.010 (2)	0.029 (2)	−0.028 (2)
C1	0.063 (2)	0.047 (2)	0.073 (2)	0.0028 (18)	0.021 (2)	0.0034 (18)
C2	0.092 (3)	0.051 (3)	0.085 (3)	0.007 (2)	0.022 (3)	0.006 (2)
C3	0.214 (11)	0.033 (3)	0.106 (6)	0.000	0.012 (7)	0.000
C4	0.065 (2)	0.052 (2)	0.061 (2)	0.0025 (19)	0.0157 (19)	0.0020 (19)
C5	0.061 (2)	0.055 (2)	0.061 (2)	0.0027 (19)	0.0164 (19)	0.0027 (19)
C6	0.070 (3)	0.055 (2)	0.067 (2)	0.007 (2)	0.016 (2)	−0.004 (2)
C7	0.068 (3)	0.055 (2)	0.060 (2)	0.005 (2)	0.0138 (19)	0.0026 (19)
C8	0.069 (3)	0.064 (3)	0.054 (2)	0.002 (2)	0.0145 (19)	0.0009 (19)
C9	0.070 (3)	0.069 (3)	0.062 (2)	0.006 (2)	0.011 (2)	−0.002 (2)
C10	0.079 (3)	0.071 (3)	0.064 (3)	0.000 (2)	0.015 (2)	−0.006 (2)
C11	0.081 (3)	0.096 (4)	0.066 (3)	−0.004 (3)	0.005 (2)	−0.007 (3)
C12	0.084 (3)	0.095 (4)	0.077 (3)	0.016 (3)	0.003 (3)	0.010 (3)
C13	0.077 (3)	0.067 (3)	0.068 (3)	0.012 (2)	0.011 (2)	0.005 (2)
C14	0.091 (4)	0.080 (4)	0.118 (5)	−0.004 (3)	0.006 (4)	−0.025 (4)
C15	0.064 (3)	0.067 (3)	0.088 (3)	0.006 (2)	0.013 (2)	−0.007 (2)

Geometric parameters (Å, º)

S1—C7	1.721 (4)	C6—C7	1.360 (5)
S1—C4	1.724 (4)	C6—H6A	0.9300
F1—C2	1.334 (5)	C7—C8	1.472 (6)
F2—C2	1.331 (6)	C8—C9	1.390 (6)
F3—C3	1.272 (6)	C8—C13	1.420 (6)
F4—C14	1.368 (8)	C9—C10	1.376 (6)
F5—C14	1.247 (7)	C9—H9A	0.9300
F6—C14	1.324 (6)	C10—C11	1.364 (6)
C1—C1^i	1.354 (8)	C10—C14	1.482 (7)
C1—C4	1.454 (5)	C11—C12	1.370 (7)
C1—C2	1.502 (6)	C11—H11A	0.9300
C2—C3	1.502 (6)	C12—C13	1.341 (7)
C3—F3^i	1.272 (6)	C12—H12A	0.9300
C3—C2^i	1.502 (6)	C13—H13A	0.9300
C4—C5	1.384 (5)	C15—H15A	0.9600
C5—C6	1.415 (6)	C15—H15B	0.9600
C5—C15	1.495 (5)	C15—H15C	0.9600
C7—S1—C4	92.2 (2)	C9—C8—C7	120.5 (4)
C1^i—C1—C4	128.7 (2)	C13—C8—C7	122.5 (4)
C1^i—C1—C2	110.8 (2)	C10—C9—C8	120.4 (4)
C4—C1—C2	120.5 (4)	C10—C9—H9A	119.8
F2—C2—F1	104.0 (4)	C8—C9—H9A	119.8
F2—C2—C3	111.1 (4)	C11—C10—C9	121.2 (5)
F1—C2—C3	111.2 (4)	C11—C10—C14	119.6 (5)
F2—C2—C1	112.6 (4)	C9—C10—C14	119.2 (5)
F1—C2—C1	112.8 (4)	C10—C11—C12	119.1 (5)
C3—C2—C1	105.2 (4)	C10—C11—H11A	120.4
F3—C3—F3^i	103.6 (9)	C12—C11—H11A	120.4
F3—C3—C2	111.5 (3)	C13—C12—C11	121.3 (5)
F3^i—C3—C2	111.3 (4)	C13—C12—H12A	119.3
F3—C3—C2^i	111.3 (4)	C11—C12—H12A	119.3
F3^i—C3—C2^i	111.5 (3)	C12—C13—C8	120.9 (5)
C2—C3—C2^i	107.7 (6)	C12—C13—H13A	119.5
C5—C4—C1	128.0 (4)	C8—C13—H13A	119.5
C5—C4—S1	111.6 (3)	F5—C14—F6	110.4 (6)
C1—C4—S1	120.4 (3)	F5—C14—F4	103.1 (6)
C4—C5—C6	111.0 (4)	F6—C14—F4	98.2 (5)
C4—C5—C15	125.7 (4)	F5—C14—C10	116.5 (6)
C6—C5—C15	123.3 (4)	F6—C14—C10	115.7 (5)
C7—C6—C5	114.8 (4)	F4—C14—C10	110.7 (5)
C7—C6—H6A	122.6	C5—C15—H15A	109.5
C5—C6—H6A	122.6	C5—C15—H15B	109.5
C6—C7—C8	129.3 (4)	H15A—C15—H15B	109.5
C6—C7—S1	110.4 (3)	C5—C15—H15C	109.5
C8—C7—S1	120.3 (3)	H15A—C15—H15C	109.5
C9—C8—C13	117.0 (4)	H15B—C15—H15C	109.5

Symmetry code: (i) −x+1, y, −z+3/2.