5-Fluoro­isatin–dimethyl sufoxide (1/1)

The title dimethyl sulfoxide (DMSO) solvate, C₈H₄FNO₂·C₂H₆OS, was isolated during a manual crystallization screen on 5-fluoro­isatin (5-fluoro­indoline-2,3-dione). Mol­ecules of 5-fluoro­isatin are linked via C—H...O inter­actions to form chains parallel to (01) from which N—H...O hydrogen-bonded DMSO mol­ecules protrude.

Key indicators

• Single-crystal X-ray study
• T = 150 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.032
• wR factor = 0.087
• Data-to-parameter ratio = 14.9

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low .......       0.97
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.93
PLAT063_ALERT_3_C Crystal Probably too Large for Beam Size .......       0.79 mm
PLAT154_ALERT_1_C The su's on the Cell Angles are Equal  (x 10000)        200 Deg.
PLAT369_ALERT_2_C Long   C(sp2)-C(sp2) Bond  C1     -   C2     ...       1.56 Ang.

Alert level G
ABSTM02_ALERT_3_G  When printed, the submitted absorption T values will be
            replaced by the scaled T values. Since the ratio of scaled T's
            is identical to the ratio of reported T values, the scaling
            does not imply a change to the absorption corrections used in
            the study.
            Ratio of Tmax expected/reported      0.934
            Tmax scaled      0.934 Tmin scaled      0.814

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

   2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   3 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

The title solvate, (I), (Figure 1) was isolated during a manual crystallization screen on 5-fluoroisatin. The crystallization screen was motivated by a wider investigation into the potential polymorphism displayed by the isomeric compounds 7-fluoroisatin and 5-fluoroisatin (Shankland et al., 2007; Mohamed et al., 2007a,b).

In the crystal structure of (I), molecules of 5-fluoroisatin form chains via C—H···O interactions with the DMSO molecules then linked to one side of these chains by N—H···O hydrogen bonds. In the same way as the 7-fluoroisatin DMSO solvate (Mohamed et al., 2007b), ribbons are formed by the interdigitation of the DMSO molecules (Figure 2 and Table 1). The C—H···O interactions for this compound occur using O2 (i.e. the O not adjacent to the N position) whereas the chain formed by 7-fluoroisatin DMSO (Mohamed et al., 2007b) uses O1. Viewing down the a axis, these ribbons can be seen to form planes parallel to (0 - 1 1) with separations of 2.38 Å and 3.49 Å where the DMSO molecules interdigitate (Figure 3).

Related literature

7-Fluoroisatin is reported to be a suitable starting material for the preparation of 7-substituted-2-indolinones, a class of compounds which are understood to display anti-convulsant activity in animals (Canas-Rodriguez & Leeming, 1972). 5-Fluoroisatin forms sheets through double N—H···O hydrogen bonds and C—H···O interactions (Naumov et al., 2000). The 1,4-dioxane (Shankland et al., 2007) and DMSO (Mohamed et al., 2007a) solvates of 7-fluoroisatin have also been prepared, as well as the oxindole derivative of 5-fluoroisatin (Mohamed et al., 2007b).

S2. Experimental

Single crystals of the title solvate were grown from a saturated dimethylsulfoxide solution by slow solvent evaporation at 298 K over a period of approximately one month.

S3. Refinement

Methyl-H atoms were located from the difference map and refined using a rigid rotor model with C—H = 0.98 Å, and with U_iso(H) = 1.5U_eq(C). All other H atoms were refined freely so that the C—H distances were in the range 0.92 (2) to 0.958 (19) Å and N—H = 0.89 (2) Å. The three reflections with the greatest discrepancies were omitted from the refinement.

Computing details

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2000) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL97 and PLATON (Spek 2003).

Figures

	Fig. 1. The asymmetric unit of (I) showing the numbering scheme used. Displacement ellipsoids are drawn at the 50% probability level and hydrogen atoms have been omitted for clarity.
	Fig. 2. The ribbon formed by 5-fluoroisatin and DMSO in (I) showing the showing the hydrogen-bonding interactions as blue dotted lines Colour code: C - dark grey, H - light grey, N - blue, O - red, F - green, S - yellow.

5-fluoroindoline-2,3-dione–dimethyl sulfoxide (1/1)

Crystal data

C10H10FNO3S	Z = 2
Mr = 243.25	F(000) = 252
Triclinic, P1	Dx = 1.513 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.2828 (13) Å	Cell parameters from 3349 reflections
b = 8.3702 (13) Å	θ = 2.6–28.3°
c = 8.7613 (14) Å	µ = 0.31 mm^−1
α = 91.326 (2)°	T = 150 K
β = 117.099 (2)°	Block, orange
γ = 97.337 (2)°	0.79 × 0.47 × 0.22 mm
V = 534.02 (15) Å^3

Data collection

Bruker SMART APEX diffractometer	2429 independent reflections
Radiation source: fine-focus sealed tube	2282 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.025
ω rotation with narrow frames scans	θmax = 28.3°, θmin = 2.5°
Absorption correction: multi-scan (SADABS; Bruker, 2001)	h = −10→10
Tmin = 0.871, Tmax = 1.000	k = −11→11
4674 measured reflections	l = −11→11

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)] = 0.032	Hydrogen site location: difference Fourier map
wR(F^2) = 0.087	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0489P)^2 + 0.1972P] where P = (Fo^2 + 2Fc^2)/3
2426 reflections	(Δ/σ)max = 0.001
163 parameters	Δρmax = 0.38 e Å^−3
0 restraints	Δρmin = −0.24 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
C1	0.27263 (19)	0.28862 (15)	0.48470 (17)	0.0240 (3)
C2	0.20213 (18)	0.15613 (15)	0.33047 (17)	0.0216 (3)
C3	0.36806 (17)	0.12356 (15)	0.32246 (16)	0.0195 (2)
C4	0.39226 (19)	0.01360 (16)	0.21618 (17)	0.0239 (3)
H1	0.293 (3)	−0.059 (2)	0.128 (2)	0.036 (5)*
C5	0.5705 (2)	0.01559 (18)	0.24401 (18)	0.0274 (3)
C6	0.71742 (19)	0.12245 (19)	0.36432 (19)	0.0300 (3)
H2	0.831 (3)	0.116 (2)	0.372 (2)	0.041 (5)*
C7	0.69151 (18)	0.23337 (18)	0.46907 (18)	0.0273 (3)
H3	0.788 (3)	0.309 (2)	0.551 (2)	0.039 (5)*
C8	0.51515 (17)	0.22925 (15)	0.44893 (16)	0.0206 (2)
N1	0.45677 (16)	0.32363 (13)	0.54376 (14)	0.0239 (2)
H4	0.533 (3)	0.393 (2)	0.635 (2)	0.038 (5)*
O1	0.17722 (16)	0.34426 (13)	0.53751 (14)	0.0355 (3)
O2	0.04277 (13)	0.10042 (12)	0.24154 (14)	0.0305 (2)
F1	0.60203 (14)	−0.09251 (12)	0.14601 (12)	0.0407 (2)
C9	0.7818 (2)	0.41521 (18)	1.11959 (19)	0.0347 (3)
H9A	0.6925	0.3163	1.0666	0.052*
H9B	0.7853	0.4489	1.2291	0.052*
H9C	0.9036	0.3944	1.1405	0.052*
C10	0.90882 (19)	0.72168 (17)	1.10596 (17)	0.0277 (3)
H10A	1.0222	0.6799	1.1285	0.042*
H10B	0.9092	0.7493	1.2154	0.042*
H10C	0.9011	0.8186	1.0438	0.042*
O3	0.73930 (14)	0.52031 (12)	0.82378 (12)	0.0277 (2)
S1	0.71618 (4)	0.57126 (4)	0.97903 (4)	0.02225 (11)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0314 (7)	0.0205 (6)	0.0234 (6)	0.0050 (5)	0.0153 (5)	0.0022 (5)
C2	0.0245 (6)	0.0186 (6)	0.0260 (6)	0.0034 (5)	0.0154 (5)	0.0009 (5)
C3	0.0205 (6)	0.0187 (5)	0.0216 (6)	0.0034 (4)	0.0115 (5)	0.0032 (4)
C4	0.0263 (6)	0.0224 (6)	0.0259 (6)	0.0050 (5)	0.0143 (5)	0.0012 (5)
C5	0.0341 (7)	0.0315 (7)	0.0289 (7)	0.0153 (6)	0.0223 (6)	0.0093 (5)
C6	0.0213 (6)	0.0432 (8)	0.0329 (7)	0.0117 (6)	0.0164 (6)	0.0171 (6)
C7	0.0195 (6)	0.0331 (7)	0.0248 (6)	0.0002 (5)	0.0070 (5)	0.0087 (5)
C8	0.0228 (6)	0.0204 (6)	0.0185 (6)	0.0032 (5)	0.0094 (5)	0.0056 (4)
N1	0.0288 (6)	0.0209 (5)	0.0188 (5)	0.0009 (4)	0.0093 (4)	−0.0016 (4)
O1	0.0441 (6)	0.0347 (6)	0.0374 (6)	0.0116 (5)	0.0261 (5)	−0.0027 (4)
O2	0.0217 (5)	0.0288 (5)	0.0409 (6)	−0.0011 (4)	0.0161 (4)	−0.0056 (4)
F1	0.0485 (6)	0.0484 (6)	0.0435 (5)	0.0244 (4)	0.0325 (5)	0.0054 (4)
C9	0.0532 (9)	0.0262 (7)	0.0314 (7)	0.0078 (6)	0.0247 (7)	0.0061 (6)
C10	0.0280 (7)	0.0254 (7)	0.0241 (6)	−0.0001 (5)	0.0086 (5)	−0.0044 (5)
O3	0.0303 (5)	0.0305 (5)	0.0186 (4)	0.0033 (4)	0.0088 (4)	−0.0030 (4)
S1	0.01999 (17)	0.02330 (18)	0.02206 (17)	0.00339 (12)	0.00868 (13)	−0.00185 (12)

Geometric parameters (Å, º)

C1—O1	1.2135 (16)	C7—C8	1.3851 (18)
C1—N1	1.3563 (18)	C7—H3	0.94 (2)
C1—C2	1.5630 (18)	C8—N1	1.4076 (16)
C2—O2	1.2066 (16)	N1—H4	0.89 (2)
C2—C3	1.4666 (17)	C9—S1	1.7787 (15)
C3—C4	1.3899 (17)	C9—H9A	0.9800
C3—C8	1.3943 (18)	C9—H9B	0.9800
C4—C5	1.3805 (19)	C9—H9C	0.9800
C4—H1	0.958 (19)	C10—S1	1.7814 (13)
C5—F1	1.3610 (15)	C10—H10A	0.9800
C5—C6	1.379 (2)	C10—H10B	0.9800
C6—C7	1.393 (2)	C10—H10C	0.9800
C6—H2	0.92 (2)	O3—S1	1.5166 (10)
O1—C1—N1	128.94 (13)	C7—C8—C3	121.03 (12)
O1—C1—C2	125.24 (13)	C7—C8—N1	127.83 (12)
N1—C1—C2	105.82 (10)	C3—C8—N1	111.14 (11)
O2—C2—C3	130.81 (12)	C1—N1—C8	111.19 (11)
O2—C2—C1	124.37 (11)	C1—N1—H4	125.1 (12)
C3—C2—C1	104.81 (11)	C8—N1—H4	123.6 (12)
C4—C3—C8	121.86 (12)	S1—C9—H9A	109.5
C4—C3—C2	131.19 (12)	S1—C9—H9B	109.5
C8—C3—C2	106.95 (11)	H9A—C9—H9B	109.5
C5—C4—C3	115.84 (12)	S1—C9—H9C	109.5
C5—C4—H1	121.2 (11)	H9A—C9—H9C	109.5
C3—C4—H1	123.0 (11)	H9B—C9—H9C	109.5
F1—C5—C6	118.51 (12)	S1—C10—H10A	109.5
F1—C5—C4	118.10 (13)	S1—C10—H10B	109.5
C6—C5—C4	123.39 (13)	H10A—C10—H10B	109.5
C5—C6—C7	120.32 (12)	S1—C10—H10C	109.5
C5—C6—H2	117.3 (12)	H10A—C10—H10C	109.5
C7—C6—H2	122.3 (12)	H10B—C10—H10C	109.5
C8—C7—C6	117.46 (13)	O3—S1—C9	106.19 (6)
C8—C7—H3	120.1 (12)	O3—S1—C10	106.02 (6)
C6—C7—H3	122.4 (12)	C9—S1—C10	97.29 (7)
O1—C1—C2—O2	3.8 (2)	C4—C5—C6—C7	1.8 (2)
N1—C1—C2—O2	−176.78 (13)	C5—C6—C7—C8	1.1 (2)
O1—C1—C2—C3	−177.15 (13)	C6—C7—C8—C3	−3.22 (19)
N1—C1—C2—C3	2.24 (13)	C6—C7—C8—N1	177.15 (12)
O2—C2—C3—C4	−3.7 (2)	C4—C3—C8—C7	2.69 (19)
C1—C2—C3—C4	177.36 (13)	C2—C3—C8—C7	−177.12 (11)
O2—C2—C3—C8	176.07 (14)	C4—C3—C8—N1	−177.62 (11)
C1—C2—C3—C8	−2.86 (13)	C2—C3—C8—N1	2.58 (14)
C8—C3—C4—C5	0.11 (19)	O1—C1—N1—C8	178.59 (13)
C2—C3—C4—C5	179.86 (13)	C2—C1—N1—C8	−0.76 (14)
C3—C4—C5—F1	178.45 (11)	C7—C8—N1—C1	178.55 (13)
C3—C4—C5—C6	−2.3 (2)	C3—C8—N1—C1	−1.12 (15)
F1—C5—C6—C7	−179.01 (12)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H4···O3	0.89 (2)	1.92 (2)	2.7935 (15)	167.0 (18)
C6—H2···O2^i	0.92 (2)	2.51 (2)	3.3484 (17)	152.1 (16)

Symmetry code: (i) x+1, y, z.