7-Fluoro­isatin–dimethyl sulfoxide (1/1)

The title dimethyl sulfoxide (DMSO) solvate, C₈H₄FNO₂·C₂H₆OS, was isolated during a manual crystallization screen on 7-fluoro­isatin (7-fluoro­indoline-2,3-dione). Mol­ecules of 7-fluoro­isatin are linked via C—H...O inter­actions to form chains parallel to the a direction, from which N—H...O hydrogen-bonded mol­ecules of DMSO protrude.

Key indicators

• Single-crystal X-ray study
• T = 150 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.031
• wR factor = 0.085
• Data-to-parameter ratio = 16.5

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT432_ALERT_2_B Short Inter X...Y Contact  O3     ..  C1      ..       2.87 Ang.

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 .....................       0.94
PLAT369_ALERT_2_C Long   C(sp2)-C(sp2) Bond  C1     -   C2     ...       1.56 Ang.
PLAT432_ALERT_2_C Short Inter X...Y Contact  O3     ..  C2      ..       2.93 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      0.943
            Tmax scaled      0.943 Tmin scaled      0.836

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

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 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 7-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), chains of 7-fluoroisatin are formed by C—H···O interactions and each 7-fluoroisatin is linked to a DMSO molecule via a N—H···O hydrogen bond. Two identical chains form ribbons by the interdigitation of the DMSO molecules (Figure 2 and Table 1). The C—H···O interactions for this compound occur using O1 (i.e. the O adjacent to the N position) whereas the chain formed by 5-fluoroisatin DMSO (Mohamed et al., 2007a) uses O2. On viewing down the c axis, these ribbons can be seen to form planes parallel to (1 - 1 0) with separations of 2.36 Å and 3.40 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). The 1,4-dioxane solvate of 7-fluoroisatin (Shankland et al., 2007) and the DMSO solvate of 5-fluoroisatin (Mohamed et al., 2007a) have also been prepared, as well as the oxindole derivative of 5-fluoroisatin (Mohamed et al., 2007b).

S2. Experimental

Single crystals of the title compound were crystallized from a saturated dimethyl sulfoxide solution by slow evaporation at 298 K over the course of four months.

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 geometrically placed and refined using a riding model with C—H = 0.95 Å and N—H = 0.88 Å, and with U_iso(H) = 1.20 U_eq(C, N). 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 7-fluoroisatin and DMSO in (I) 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.
	Fig. 3. Packing diagram showing the stacking of the ribbons in (I). Colour code: C - dark grey, H - light grey, N - blue, O - red, F - green, S - yellow.

7-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 = 7.4917 (12) Å	Cell parameters from 3848 reflections
b = 8.4911 (14) Å	θ = 2.4–28.3°
c = 8.9542 (15) Å	µ = 0.31 mm^−1
α = 106.207 (2)°	T = 150 K
β = 98.648 (2)°	Rhomboid block, orange
γ = 96.242 (3)°	0.53 × 0.26 × 0.19 mm
V = 533.89 (15) Å^3

Data collection

Bruker SMART APEX diffractometer	2439 independent reflections
Radiation source: fine-focus sealed tube	2355 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.028
ω rotation with narrow frames scans	θmax = 28.3°, θmin = 2.4°
Absorption correction: multi-scan (SADABS; Bruker, 2001)	h = −9→9
Tmin = 0.886, Tmax = 1.000	k = −10→11
4718 measured reflections	l = −11→11

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.031	H-atom parameters constrained
wR(F^2) = 0.085	w = 1/[σ^2(Fo^2) + (0.04P)^2 + 0.2177P] where P = (Fo^2 + 2Fc^2)/3
S = 1.08	(Δ/σ)max = 0.001
2436 reflections	Δρmax = 0.37 e Å^−3
148 parameters	Δρmin = −0.25 e Å^−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 1997), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.036 (6)

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	0.48025 (17)	0.24882 (16)	0.36792 (14)	0.0223 (3)
C2	0.33034 (17)	0.10687 (15)	0.37074 (14)	0.0225 (3)
C3	0.33940 (16)	0.12133 (15)	0.53918 (14)	0.0205 (2)
C4	0.24087 (18)	0.03106 (16)	0.61588 (17)	0.0264 (3)
H4A	0.1467	−0.0588	0.5575	0.032*
C5	0.2834 (2)	0.07534 (17)	0.78007 (17)	0.0290 (3)
H5A	0.2168	0.0159	0.8349	0.035*
C6	0.42278 (19)	0.20619 (17)	0.86501 (15)	0.0265 (3)
H6A	0.4514	0.2354	0.9773	0.032*
C7	0.51927 (17)	0.29330 (15)	0.78552 (14)	0.0215 (2)
C8	0.47933 (16)	0.25344 (14)	0.62275 (14)	0.0185 (2)
N1	0.56176 (14)	0.32541 (13)	0.52209 (12)	0.0208 (2)
H1A	0.6534	0.4085	0.5539	0.025*
O1	0.51535 (14)	0.28218 (13)	0.25143 (11)	0.0301 (2)
O2	0.23455 (14)	0.00815 (12)	0.25429 (11)	0.0320 (2)
F1	0.65707 (11)	0.41893 (10)	0.86828 (9)	0.0312 (2)
C9	1.0906 (2)	0.46043 (18)	0.75001 (16)	0.0293 (3)
H9A	0.9919	0.4039	0.7857	0.044*
H9B	1.2019	0.4892	0.8315	0.044*
H9C	1.1139	0.3867	0.6516	0.044*
C10	0.9842 (2)	0.74243 (17)	0.90954 (15)	0.0302 (3)
H10A	0.9334	0.8442	0.9103	0.045*
H10B	1.0995	0.7701	0.9863	0.045*
H10C	0.8972	0.6662	0.9381	0.045*
O3	0.83993 (12)	0.59461 (11)	0.60778 (10)	0.0224 (2)
S1	1.02562 (4)	0.64525 (4)	0.71564 (3)	0.02143 (12)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0228 (6)	0.0253 (6)	0.0189 (6)	0.0085 (5)	0.0023 (4)	0.0060 (5)
C2	0.0230 (6)	0.0207 (6)	0.0213 (6)	0.0072 (5)	−0.0003 (4)	0.0032 (5)
C3	0.0210 (6)	0.0184 (5)	0.0208 (6)	0.0053 (4)	0.0016 (4)	0.0040 (4)
C4	0.0238 (6)	0.0210 (6)	0.0336 (7)	0.0016 (5)	0.0054 (5)	0.0074 (5)
C5	0.0332 (7)	0.0267 (6)	0.0324 (7)	0.0049 (5)	0.0131 (5)	0.0134 (5)
C6	0.0332 (7)	0.0289 (6)	0.0204 (6)	0.0096 (5)	0.0077 (5)	0.0092 (5)
C7	0.0226 (6)	0.0211 (6)	0.0186 (6)	0.0035 (4)	0.0012 (4)	0.0040 (4)
C8	0.0194 (5)	0.0183 (5)	0.0182 (5)	0.0054 (4)	0.0026 (4)	0.0059 (4)
N1	0.0216 (5)	0.0227 (5)	0.0173 (5)	0.0006 (4)	0.0019 (4)	0.0066 (4)
O1	0.0332 (5)	0.0411 (6)	0.0196 (4)	0.0103 (4)	0.0059 (4)	0.0126 (4)
O2	0.0350 (5)	0.0264 (5)	0.0246 (5)	0.0042 (4)	−0.0070 (4)	−0.0016 (4)
F1	0.0330 (4)	0.0338 (4)	0.0188 (4)	−0.0061 (3)	−0.0036 (3)	0.0038 (3)
C9	0.0341 (7)	0.0335 (7)	0.0249 (6)	0.0150 (6)	0.0060 (5)	0.0124 (5)
C10	0.0391 (7)	0.0267 (6)	0.0197 (6)	0.0048 (5)	−0.0008 (5)	0.0024 (5)
O3	0.0201 (4)	0.0250 (4)	0.0195 (4)	0.0013 (3)	−0.0012 (3)	0.0060 (3)
S1	0.01927 (17)	0.02451 (18)	0.01990 (17)	−0.00010 (11)	0.00060 (11)	0.00866 (12)

Geometric parameters (Å, º)

C1—O1	1.2118 (16)	C7—F1	1.3572 (14)
C1—N1	1.3640 (16)	C7—C8	1.3783 (17)
C1—C2	1.5640 (18)	C8—N1	1.3999 (15)
C2—O2	1.2087 (15)	N1—H1A	0.8800
C2—C3	1.4692 (17)	S1—O3	1.5122 (9)
C3—C4	1.3883 (18)	S1—C9	1.7848 (14)
C3—C8	1.3990 (16)	S1—C10	1.7914 (14)
C4—C5	1.389 (2)	C9—H9A	0.9800
C4—H4A	0.9500	C9—H9B	0.9800
C5—C6	1.393 (2)	C9—H9C	0.9800
C5—H5A	0.9500	C10—H10A	0.9800
C6—C7	1.3816 (18)	C10—H10B	0.9800
C6—H6A	0.9500	C10—H10C	0.9800
O1—C1—N1	127.72 (13)	C7—C8—C3	118.45 (11)
O1—C1—C2	126.38 (12)	C7—C8—N1	129.33 (11)
N1—C1—C2	105.91 (10)	C3—C8—N1	112.22 (10)
O2—C2—C3	130.21 (13)	C1—N1—C8	110.58 (10)
O2—C2—C1	124.66 (12)	C1—N1—H1A	124.7
C3—C2—C1	105.10 (10)	C8—N1—H1A	124.7
C4—C3—C8	121.77 (11)	O3—S1—C9	106.48 (6)
C4—C3—C2	132.07 (12)	O3—S1—C10	105.88 (6)
C8—C3—C2	106.16 (11)	C9—S1—C10	97.75 (6)
C3—C4—C5	118.36 (12)	S1—C9—H9A	109.5
C3—C4—H4A	120.8	S1—C9—H9B	109.5
C5—C4—H4A	120.8	H9A—C9—H9B	109.5
C4—C5—C6	120.58 (12)	S1—C9—H9C	109.5
C4—C5—H5A	119.7	H9A—C9—H9C	109.5
C6—C5—H5A	119.7	H9B—C9—H9C	109.5
C7—C6—C5	119.82 (12)	S1—C10—H10A	109.5
C7—C6—H6A	120.1	S1—C10—H10B	109.5
C5—C6—H6A	120.1	H10A—C10—H10B	109.5
F1—C7—C8	119.24 (11)	S1—C10—H10C	109.5
F1—C7—C6	119.73 (11)	H10A—C10—H10C	109.5
C8—C7—C6	121.02 (12)	H10B—C10—H10C	109.5
O1—C1—C2—O2	2.9 (2)	C5—C6—C7—C8	0.33 (19)
N1—C1—C2—O2	−177.03 (12)	F1—C7—C8—C3	178.67 (10)
O1—C1—C2—C3	−178.51 (12)	C6—C7—C8—C3	−0.56 (18)
N1—C1—C2—C3	1.60 (12)	F1—C7—C8—N1	−0.18 (19)
O2—C2—C3—C4	−1.6 (2)	C6—C7—C8—N1	−179.41 (12)
C1—C2—C3—C4	179.85 (13)	C4—C3—C8—C7	0.20 (18)
O2—C2—C3—C8	177.65 (13)	C2—C3—C8—C7	−179.16 (10)
C1—C2—C3—C8	−0.88 (12)	C4—C3—C8—N1	179.24 (11)
C8—C3—C4—C5	0.37 (19)	C2—C3—C8—N1	−0.12 (13)
C2—C3—C4—C5	179.55 (13)	O1—C1—N1—C8	178.40 (12)
C3—C4—C5—C6	−0.6 (2)	C2—C1—N1—C8	−1.72 (13)
C4—C5—C6—C7	0.3 (2)	C7—C8—N1—C1	−179.85 (12)
C5—C6—C7—F1	−178.89 (12)	C3—C8—N1—C1	1.25 (14)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O3	0.88	1.89	2.7679 (14)	175
C6—H6A···O1^i	0.95	2.34	3.2870 (17)	175

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