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

Journal logoSTRUCTURAL
CHEMISTRY
ISSN: 2053-2296
Volume 62| Part 6| June 2006| Pages o321-o323
doi:10.1107/S0108270106014284

Hydrogen-bonded chains of rings linked by iodo–carbonyl inter­actions in 5-iodo­isatin and hydrogen-bonded sheets in 7-tri­fluoro­methyl­isatin

CROSSMARK_Color_square_no_text.svg
Simon J. Garden,a Angelo C. Pinto,a James L. Wardell,b John N. Lowc and Christopher Glidewelld*

aInstituto de Química, Departamento de Química Orgânica, Universidade Federal do Rio de Janeiro, CP 68563, 21945-970 Rio de Janeiro, RJ, Brazil, bInstituto de Química, Departamento de Química Inorgânica, Universidade Federal do Rio de Janeiro, CP 68563, 21945-970 Rio de Janeiro, RJ, Brazil, cDepartment of Chemistry, University of Aberdeen, Meston Walk, Old Aberdeen AB24 3UE, Scotland, and dSchool of Chemistry, University of St Andrews, Fife KY16 9ST, Scotland
*Correspondence e-mail: cg@st-andrews.ac.uk

(Received 19 April 2006; accepted 20 April 2006; online 16 May 2006)

In 5-iodo­isatin (5-iodo-1H-indole-2,3-dione), C8H4INO2, the mol­ecules are linked into chains of rings by N—H⋯O and C—H⋯O hydrogen bonds, and these chains are linked into sheets by iodo–carbonyl inter­actions. In 7-trifluoro­methyl­isatin (7-trifluoro­methyl-1H-indole-2,3-dione), C9H4F3NO2, the mol­ecules are linked into sheets of centrosymmetric R22(8) and R66(34) rings by N—H⋯O and C—H⋯O hydrogen bonds.

Comment

Isatin and its derivatives are versatile substrates, useful in the syntheses of a large variety of heterocyclic compounds, such as indoles and quinolines, and as raw materials for drug synthesis. Isatins have also been found in mammalian tissue and their function as a modulator of biochemical processes has been the subject of much discussion (da Silva et al., 2001[Silva, J. F. M. da, Garden, S. J. & Pinto, A. C. (2001). J. Braz. Chem. Soc. 12, 273-286.]). We report here the mol­ecular and supra­molecular structures of two monosubstituted isatins, namely 5-iodo­isatin, (I)[link], and 7-tri­fluoromethyl­isatin, (II)[link] (Figs. 1[link] and 2[link]).

[Scheme 1]

The bond distances in compounds (I)[link] and (II)[link] (Table 3[link]) are, in general, similar to those in isatin itself [Cambridge Structural Database (CSD; Allen, 2002[Allen, F. H. (2002). Acta Cryst. B58, 380-388.]) refcode ISATIN03 (Palenik et al., 1990[Palenik, G. J., Koziol, A. E., Katritzky, A. R. & Fan, W.-Q. (1990). Chem. Commun. pp. 715-716.])], although with a rather smaller range for the C—C bonds in the fragment C3a/C4–C7/C7a. In particular, the C2—C3 bond, which is longer than a typical single bond between two three-coordinate C atoms, is of similar length in each of (I)[link] and (II)[link] to that in isatin itself, compound (III)[link] [1.555 (3) Å; Palenik et al., 1990[Palenik, G. J., Koziol, A. E., Katritzky, A. R. & Fan, W.-Q. (1990). Chem. Commun. pp. 715-716.]], where this long bond was ascribed to lone-pair–lone-pair repulsions involving two adjacent O atoms. This deduction was based on a survey of 1,2-diketone structures recorded in the CSD; the C(O)—C(O) distance was found to have a mean value of 1.542 (17) Å in cis-1,2-diketones but 1.476 (27) Å in trans-1,2-diketones. Similarly, long C—C bonds are typical of simple oxalate derivatives (Allen et al., 1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

In (I)[link], the mol­ecules are linked into chains of rings by a combination of N—H⋯O and C—H⋯O hydrogen bonds (Table 1[link]), and these chains are linked into sheets by a short and almost linear iodo–carbonyl inter­action. Atoms N1 and C7 in the mol­ecule at (x, y, z) act as hydrogen-bond donors, respectively, to atoms O3 and O2 in the mol­ecule at (−x + 2, y − [{1\over 2}], −z + [{3\over 2}]), so forming a C(5)C(6)[R22(9)] chain of rings (Bernstein et al., 1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]) running parallel to the [010] direction and generated by the 21 screw axis along (1, y, [3\over4]) (Fig. 3[link]). Atom I5 in the mol­ecule at (x, y, z) makes a rather short contact with atom O2 in the mol­ecule at (x − 1, y, z − 1) [I⋯Oiv = 3.226 (2) Å and C—I⋯Oiv = 167.2 (2)°; symmetry code: (iv) x − 1, y, z − 1], and this inter­action links the [010] chains to form a ([\overline{1}]01) sheet of R22(9) and R43(16) (Bernstein et al., 1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]; Starbuck et al., 1999[Starbuck, J., Norman, N. C. & Orpen, A. G. (1999). New J. Chem. 23, 969-972.]) rings (Fig. 3[link]).

The mol­ecules of (II)[link] are linked by paired N—H⋯O hydrogen bonds (Table 2[link]) into centrosymmetric dimers, and these dimers are further linked by a single C—H⋯O hydrogen bond to form sheets. Amine atom N1 in the mol­ecule at (x, y, z) acts as a hydrogen-bond donor to carbonyl atom O2 in the mol­ecule at (−x + 1, −y + 1, −z + 1), so generating an R22(8) (Bernstein et al., 1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]) dimer centred at ([1\over2], [1\over2], [1\over2]) (Fig. 4[link]). In addition, atoms C6 in the mol­ecules at (x, y, z) and (−x + 1, −y + 1, −z + 1) act as donors, respectively, to carbonyl atoms O3 in the mol­ecules at (x − 1, −y + [{1\over 2}], z + [{1\over 2}]) and (−x + 2, y + [{1\over 2}], −z + [{1\over 2}]), which are components of the R22(8) dimers centred at (−[1\over2], 0, 1) and ([3\over2], 1, 0), respectively. In a similar way, atoms O3 in the mol­ecules at (x, y, z) and (−x + 1, −y + 1, −z + 1) accept hydrogen bonds from atoms C6 in the mol­ecules at (x + 1, −y + [{1\over 2}], z − [{1\over 2}]) and (−x, y + [{1\over 2}], −z + [{3\over 2}]), which are themselves components of the dimers centred at ([3\over2], 0, 0) and (−[1\over2], 1, 1), respectively. Propagation by the space group then generates a (102) sheet built from R22(8) and R66(34) rings, both centrosymmetric, alternating in a chess-board fashion (Fig. 4[link]). However, there are no direction-specific inter­actions between adjacent sheets; in particular, C—H⋯π(arene) hydrogen bonds and aromatic π–π stacking inter­actions are both absent from the structure of (II)[link].

It is of inter­est to compare the supra­molecular aggregation in compounds (I)[link] and (II)[link] with that in (III)[link]; for this purpose we have used the atomic coordinates for ISATIN03 (Palenik et al., 1990[Palenik, G. J., Koziol, A. E., Katritzky, A. R. & Fan, W.-Q. (1990). Chem. Commun. pp. 715-716.]) retrieved from the CSD. The mol­ecules are linked by paired N—H⋯O hydrogen bonds into centrosymmetric dimers, as first established by Goldschmidt & Llewellyn (1950[Goldschmidt, G. H. & Llewellyn, F. J. (1950). Acta Cryst. 3, 294-299.]). In addition, however, we find that these dimers are weakly linked into (100) sheets by a single aromatic π–π stacking inter­action. The aryl rings of the mol­ecules at (x, y, z) and (x, −y + [{1\over 2}], z ± [{1\over 2}]) are inclined to one another at only 0.7 (2)°; the separation of ring centroids is 3.857 (2) Å, with an inter­planar spacing of ca 3.444 Å, corresponding to a ring offset of ca 1.736 Å. Propagation of this inter­action links the hydrogen-bonded R22(8) dimers into a sheet (Fig. 5[link]). If individual mol­ecules are regarded as the nodes of the resulting net, this is of (6,3)-type, while if the dimers are regarded as the nodes then the net is of (4,4)-type (Batten & Robson, 1998[Batten, S. R. & Robson, R. (1998). Angew. Chem. Int. Ed. 37, 1460-1494.]).

[Figure 1]
Figure 1
The mol­ecule of (I)[link], showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2]
Figure 2
The mol­ecule of (II)[link], showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 3]
Figure 3
Part of the crystal structure of (I)[link], showing the formation of a ([\overline{1}]01) sheet built from alternating chains of R22(9) and R43(16) rings. For the sake of clarity, H atoms not involved in the motifs shown have been omitted. Atoms marked with an asterisk (*), a hash (#), a dollar sign ($), an ampersand (&) or an `at' sign (@) are at the symmetry positions (−x + 2, y − [{1\over 2}], −z + [3\over2]), (−x + 2, y + [{1\over 2}], −z + [3\over2]), (−x + 1, y − [{1\over 2}], −z + [{1\over 2}]), (x − 1, y, z − 1) and (−x + 1, y + [{1\over 2}], −z + [{1\over 2}]), respectively.
[Figure 4]
Figure 4
A stereoview of part of the crystal structure of (II)[link], showing the formation of a (102) sheet built from alternating R22(8) and R66(34) rings. For the sake of clarity, H atoms not involved in the motifs shown have been omitted.
[Figure 5]
Figure 5
A stereoview of part of the crystal structure of (III)[link], showing the formation of a (100) sheet of π-stacked R22(8) dimers. For the sake of clarity, H atoms not involved in the motifs shown have been omitted. The original atomic coordinates (Palenik et al., 1990[Palenik, G. J., Koziol, A. E., Katritzky, A. R. & Fan, W.-Q. (1990). Chem. Commun. pp. 715-716.]) have been used.

Experimental

5-Iodo­isatin was prepared by the reaction of aqueous KICl2 with isatin (Garden et al., 2001[Garden, S. J., Torres, J. C., de Souza Melo, S. C., Lima, A. S., Pinto, A. C. & Lima, E. L. S. (2001). Tetrahedron Lett. 42, 2089-2092.]). 7-Trifluoro­methyl­isatin was prepared following a modified Sandmeyer methodology (Garden et al., 1997[Garden, S. J., Torres, J. C., Ferreira, A. A., Silva, R. B. & Pinto, A. C. (1997). Tetrahedron Lett. 38, 1501-1504.]).

Compound (I)[link]

Crystal data

  • C8H4INO2

  • Mr = 273.02

  • Monoclinic, P 21 /c

  • a = 9.3617 (6) Å

  • b = 11.0930 (5) Å

  • c = 7.6482 (4) Å

  • β = 101.146 (2)°

  • V = 779.28 (7) Å3

  • Z = 4

  • Dx = 2.327 Mg m−3

  • Mo Kα radiation

  • μ = 4.06 mm−1

  • T = 120 (2) K

  • Block, red

  • 0.48 × 0.42 × 0.22 mm
Data collection

  • Bruker–Nonius KappaCCD diffractometer

  • φ and ω scans

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2003[Sheldrick, G. M. (2003). SADABS. Version 2.10. University of Göttingen, Germany.]) Tmin = 0.142, Tmax = 0.408

  • 8625 measured reflections

  • 1778 independent reflections

  • 1623 reflections with I > 2σ(I)

  • Rint = 0.031

  • θmax = 27.5°
Refinement

  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.020

  • wR(F2) = 0.051

  • S = 1.09

  • 1778 reflections

  • 97 parameters

  • H-atom parameters constrained

  • w = 1/[σ2(Fo2) + (0.0231P)2 + 0.9452P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max = 0.001

  • Δρmax = 0.74 e Å−3

  • Δρmin = −0.97 e Å−3

Table 1
Hydrogen-bond geometry (Å, °) for (I)[link]

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N1—H1⋯O3i 0.88 2.02 2.892 (3) 170
C7—H7⋯O2i 0.95 2.35 3.278 (3) 164
Symmetry code: (i) [-x+2, y-{\script{1\over 2}}, -z+{\script{3\over 2}}].

Compound (II)[link]

Crystal data

  • C9H4F3NO2

  • Mr = 215.13

  • Monoclinic, P 21 /c

  • a = 5.1704 (2) Å

  • b = 15.5609 (11) Å

  • c = 10.5780 (7) Å

  • β = 102.713 (4)°

  • V = 830.20 (9) Å3

  • Z = 4

  • Dx = 1.721 Mg m−3

  • Mo Kα radiation

  • μ = 0.17 mm−1

  • T = 120 (2) K

  • Plate, yellow

  • 0.35 × 0.15 × 0.02 mm
Data collection

  • Bruker–Nonius KappaCCD diffractometer

  • φ and ω scans

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2003[Sheldrick, G. M. (2003). SADABS. Version 2.10. University of Göttingen, Germany.]) Tmin = 0.934, Tmax = 0.997

  • 9284 measured reflections

  • 1893 independent reflections

  • 1412 reflections with I > 2σ(I)

  • Rint = 0.037

  • θmax = 27.5°
Refinement

  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.041

  • wR(F2) = 0.105

  • S = 1.04

  • 1893 reflections

  • 137 parameters

  • H-atom parameters constrained

  • w = 1/[σ2(Fo2) + (0.0465P)2 + 0.3729P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max < 0.001

  • Δρmax = 0.29 e Å−3

  • Δρmin = −0.26 e Å−3

Table 2
Hydrogen-bond geometry (Å, °) for (II)[link]

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N1—H1⋯O2ii 0.88 2.06 2.913 (2) 164
C6—H6⋯O3iii 0.95 2.33 3.219 (2) 156
Symmetry codes: (ii) -x+1, -y+1, -z+1; (iii) [x-1, -y+{\script{1\over 2}}, z+{\script{1\over 2}}].

Table 3
Selected bond distances (Å) for compounds (I) and (II)

  (I) (II)
N1—C2 1.356 (3) 1.360 (2)
C2—C3 1.565 (3) 1.562 (2)
C3—C3a 1.468 (3) 1.473 (2)
C3a—C7a 1.400 (3) 1.402 (2)
C7a—N1 1.405 (3) 1.408 (2)
C2—O2 1.210 (3) 1.219 (2)
C3—O3 1.208 (4) 1.205 (2)
C5—I5 2.101 (2)  
C7—C71   1.496 (2)

For each of (I)[link] and (II)[link], the space group P21/c was uniquely assigned from the systematic absences. All H atoms were located in difference maps and then treated as riding atoms, with C—H and N—H = 0.95 and 0.88 Å, respectively, and Uiso(H) = 1.2Ueq(C,N)

For both compounds, data collection: COLLECT (Hooft, 1999[Hooft, R. W. W. (1999). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: DENZO (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]) and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: OSCAIL (McArdle, 2003[McArdle, P. (2003). OSCAIL for Windows. Version 10. Crystallography Centre, Chemistry Department, NUI Galway, Ireland.]) and SHELXS97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); program(s) used to refine structure: OSCAIL and SHELXL97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); molecular graphics: PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]); software used to prepare material for publication: SHELXL97 and PRPKAPPA (Ferguson, 1999[Ferguson, G. (1999). PRPKAPPA. University of Guelph, Canada.]).

Supporting information

Crystal structure: contains datablocks global, I, II. DOI: 10.1107/S0108270106014284/sk3019sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S0108270106014284/sk3019Isup2.hkl

Structure factors: contains datablock II. DOI: 10.1107/S0108270106014284/sk3019IIsup3.hkl


Comment top

Isatin and its derivatives are versatile substrates, useful in the syntheses of a large variety of heterocyclic compounds, such as indoles and quinolines, and as raw materials for drug synthesis. Isatins have also been found in mammalian tissue and their function as a modulator of biochemical processes has been the subject of much discussion (da Silva et al., 2001). We report here the molecular and supramolecular structures of two monosubstituted isatins, 5-iodoisatin, (I), and 7-trifluoromethylisatin, (II) (Figs. 1 and 2).

The bond distances in compounds (I) and (II) (Table 3) are, in general, fairly similar to those in isatin itself [Cambridge Structural Database (CSD; Allen, 2002) refcode ISATIN03; Palenik et al., 1990], although with a rather smaller range for the C—C bonds in the fragment C3A/C4–C7/C7A. In particular, the C2—C3 bond, which is longer than a typical single bond between two three-coordinate C atoms, is of similar length in each of (I) and (II) to that in isatin [1.555 (3) Å; Palenik et al., 1990], where this long bond was ascribed to lone-pair–lone-pair repulsions involving two adjacent O atoms. This deduction was based on a survey of 1,2-diketone structures recorded in the CSD: the C(O)—C(O) distance was found to have a mean value of 1.542 (17) Å in cis-1,2-diketones but 1.476 (27) Å in trans-1,2-diketones. Similarly, long C—C bonds are typical of simple oxalate derivatives (Allen et al., 1987).

In compound (I), the molecules are linked into chains of rings by a combination of N—H···O and C—H···O hydrogen bonds (Table 1), and these chains are linked into sheets by a short and almost linear iodo–carbonyl interaction. Atoms N1 and C7 in the molecule at (x, y, z) act as hydrogen-bond donors, respectively, to atoms O3 and O2 in the molecule at (2 − x, −1/2 + y, 3/2 − z), so forming a C(5)C(6)[R22(9)] chain of rings (Bernstein et al., 1995) running parallel to the [010] direction and generated by the 21 screw axis along (1, y, 3/4) (Fig. 3). Atom I5 in the molecule at (x, y, z) makes a rather short contact with atom O2 in the molecule at (−1 + x, y, −1 + z) [I···Oiv = 3.226 (2) Å and C—I···Oiv = 167.2 (2)°; symmetry code: (iv) x − 1, y, z − 1], and this interaction links the [010] chains to form a (101) sheet of R22(9) and R34(16) (Bernstein et al., 1995; Starbuck et al., 1999) rings (Fig. 3).

The molecules of compound (II) are linked by paired N—H···O hydrogen bonds (Table) into centrosymmetric dimers, and these dimers are further linked by a single C—H···O hydrogen bond to form sheets. Amino atom N1 in the molecule at (x, y, z) acts as a hydrogen-bond donor to carbonyl atom O2 in the molecule at (1 − x, 1 − y, 1 − z), so generating an R22(8) (Bernstein et al., 1995) dimer centred at (1/2, 1/2, 1/2) (Fig. 4). In addition, atoms C6 in the molecules at (x, y, z) and (1 − x, 1 − y, 1 − z) act as donors, respectively, to carbonyl atoms O3 in the molecules at (−1 + x, 1/2 − y, 1/2 + z) and (2 − x, 1/2 + y, 1/2 − z), which are components of the R22(8) dimers centred at (−1/2, 0, 1) and (3/2, 1, 0), respectively. In a similar way, atoms O3 in the molecules at (x, y, z) and (1 − x, 1 − y, 1 − z) accept hydrogen bonds from atoms C6 in the molecules at (1 + x, 1/2 − y, −1/2 + z) and (−x, 1/2 + y, 3/2 − z), which are themselves components of the dimers centred at (3/2, 0, 0) and (−1/2, 1, 1), respectively. Propagation by the space group then generates a (102) sheet built from R22(8) and R66(34) rings, both centrosymmetric, alternating in chess-board fashion (Fig. 4). However, there are no direction-specific interactions between adjacent sheets; in particular, C—H···π(arene) hydrogen bonds and aromatic π–π stacking interactions are both absent from the structure of (II).

It is of interest to compare the supramolecular aggregation in compounds (I) and (II) with that in isatin itself, compound (III); for this purpose we have used the atomic coordinates for ISATIN03 (Palenik et al., 1990) retrieved from the CSD. The molecules are linked by paired N—H···O hydrogen bonds into centrosymmetric dimers, as first established by Goldschmidt & Llewellyn (1950). In addition, however, we find that these dimers are weakly linked into (100) sheets by a single aromatic π–π stacking interaction. The aryl rings of the molecules at (x, y, z) and (x, 1/2 − y, ±1/2 + z) are inclined to one another at only 0.7 (2)°; the ring centroid separation is 3.857 (2) Å, with an interplanar spacing of ca 3.444 Å, corresponding to a ring offset of ca 1.736 Å. Propagation of this interaction links the hydrogen-bonded R22(8) dimers into a sheet (Fig. 5). If individual molecules are regarded as the nodes of the resulting net, this is of (6,3)-type, while if the dimers are regarded as the nodes then the net is of (4,4)-type (Batten & Robson, 1998).

Experimental top

5-Iodoisatin was prepared by the reaction of aqueous KICl2 with isatin (Garden et al., 2001). 7-Trifluoromethylisatin was prepared following a modified Sandmeyer methodology (Garden et al., 1997).

Refinement top

For each of (I) and (II), the space group P21/c was uniquely assigned from the systematic absences. All H atoms were located in difference maps and then treated as riding atoms, with C—H and N—H distances of 0.95 and 0.88 Å, respectively, and with Uiso(H) = 1.2Ueq(C,N)

Computing details top

For both compounds, data collection: COLLECT (Hooft, 1999); cell refinement: DENZO (Otwinowski & Minor, 1997) and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: OSCAIL (McArdle, 2003) and SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: OSCAIL and SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 and PRPKAPPA (Ferguson, 1999).

Figures top
[Figure 1] Fig. 1. The molecule of (I), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. The molecule of (II), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 3] Fig. 3. Part of the crystal structure of (I), showing the formation of a (101) sheet built from alternating chains of R22(9) and R34(16) rings. For the sake of clarity, H atoms not involved in the motifs shown have been omitted. Atoms marked with an asterisk (*), a hash (#), a dollar sign ($), an ampersand (&) or an at sign (@) are at the symmetry positions (2 − x, −1/2 + y, 1.5 − z), (2 − x, 1/2 + y, 1.5 − z), (1 − x, −1/2 + y, 1/2 − z), (−1 + x, y, −1 + z) and (1 − x, 1/2 + y, 1/2 − z), respectively.
[Figure 4] Fig. 4. A stereoview of part of the crystal structure of (II), showing the formation of a (102) sheet built from alternating R22(8) and R66(34) rings. For the sake of clarity, H atoms not involved in the motifs shown have been omitted.
[Figure 5] Fig. 5. A stereoview of part of the crystal structure of (III), showing the formation of a (100) sheet of π-stacked R22(8) dimers. For the sake of clarity, H atoms not involved in the motifs shown have been omitted. The original atom coordinates (Palenik et al., 1990) have been used.
(I) 5-iodo-1H-indole-2,3-dione top
Crystal data top
C8H4INO2F(000) = 512
Mr = 273.02Dx = 2.327 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1818 reflections
a = 9.3617 (6) Åθ = 2.9–27.4°
b = 11.0930 (5) ŵ = 4.06 mm−1
c = 7.6482 (4) ÅT = 120 K
β = 101.146 (2)°Block, red
V = 779.28 (7) Å30.48 × 0.42 × 0.22 mm
Z = 4
Data collection top
Bruker–Nonius KappaCCD
diffractometer		1778 independent reflections
Radiation source: Bruker-Nonius FR591 rotating anode1623 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.031
Detector resolution: 9.091 pixels mm-1θmax = 27.5°, θmin = 3.7°
ϕ and ω scansh = −12→11
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		k = −14→11
Tmin = 0.142, Tmax = 0.408l = −9→9
8625 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)] = 0.020Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.051H-atom parameters constrained
S = 1.09 w = 1/[σ2(Fo2) + (0.0231P)2 + 0.9452P]
where P = (Fo2 + 2Fc2)/3
1778 reflections(Δ/σ)max = 0.001
97 parametersΔρmax = 0.74 e Å−3
0 restraintsΔρmin = −0.97 e Å−3
Crystal data top
C8H4INO2V = 779.28 (7) Å3
Mr = 273.02Z = 4
Monoclinic, P21/cMo Kα radiation
a = 9.3617 (6) ŵ = 4.06 mm−1
b = 11.0930 (5) ÅT = 120 K
c = 7.6482 (4) Å0.48 × 0.42 × 0.22 mm
β = 101.146 (2)°
Data collection top
Bruker–Nonius KappaCCD
diffractometer		1778 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		1623 reflections with I > 2σ(I)
Tmin = 0.142, Tmax = 0.408Rint = 0.031
8625 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0200 restraints
wR(F2) = 0.051H-atom parameters constrained
S = 1.09Δρmax = 0.74 e Å−3
1778 reflectionsΔρmin = −0.97 e Å−3
97 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
N10.9489 (2)0.59853 (18)0.6930 (3)0.0147 (4)
C20.9913 (3)0.7132 (2)0.7379 (3)0.0146 (5)
O21.0895 (2)0.74742 (17)0.8541 (2)0.0198 (4)
C30.8832 (2)0.7957 (2)0.6088 (3)0.0121 (5)
O30.88944 (18)0.90452 (17)0.6072 (2)0.0173 (4)
C3A0.7797 (3)0.7125 (2)0.5018 (3)0.0133 (3)
C40.6559 (3)0.7327 (2)0.3725 (3)0.0122 (5)
C50.5766 (3)0.6322 (2)0.2997 (3)0.0134 (5)
I50.381940 (16)0.653274 (14)0.11269 (2)0.01570 (8)
C60.6229 (2)0.5167 (2)0.3537 (3)0.0145 (5)
C70.7475 (3)0.4957 (2)0.4822 (3)0.0133 (3)
C7A0.8244 (3)0.5958 (2)0.5568 (3)0.0133 (3)
H10.99380.53390.74290.018*
H40.62640.81200.33510.015*
H60.56760.44960.30100.017*
H70.77840.41620.51720.016*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0143 (10)0.0109 (10)0.0166 (10)0.0022 (8)−0.0029 (9)0.0012 (8)
C20.0150 (12)0.0159 (12)0.0131 (11)0.0013 (9)0.0029 (9)−0.0005 (9)
O20.0152 (9)0.0228 (10)0.0183 (9)−0.0024 (8)−0.0046 (7)−0.0017 (7)
C30.0132 (12)0.0139 (12)0.0096 (11)0.0003 (8)0.0031 (9)−0.0013 (8)
O30.0191 (10)0.0122 (9)0.0189 (10)−0.0012 (7)−0.0003 (8)−0.0013 (6)
C3A0.0148 (7)0.0110 (7)0.0139 (6)0.0002 (5)0.0023 (5)−0.0004 (5)
C40.0125 (11)0.0116 (11)0.0120 (11)0.0025 (9)0.0012 (9)−0.0001 (8)
C50.0114 (12)0.0170 (12)0.0109 (11)0.0001 (9)0.0000 (9)−0.0006 (9)
I50.01298 (11)0.01754 (11)0.01439 (11)−0.00088 (6)−0.00279 (7)−0.00040 (6)
C60.0122 (12)0.0123 (12)0.0178 (12)−0.0029 (9)0.0000 (10)0.0004 (9)
C70.0148 (7)0.0110 (7)0.0139 (6)0.0002 (5)0.0023 (5)−0.0004 (5)
C7A0.0148 (7)0.0110 (7)0.0139 (6)0.0002 (5)0.0023 (5)−0.0004 (5)
Geometric parameters (Å, º) top
N1—C21.356 (3)C4—C51.395 (3)
N1—C7A1.405 (3)C4—H40.95
N1—H10.88C5—C61.389 (3)
C2—O21.210 (3)C5—I52.101 (2)
C2—C31.565 (3)C6—C71.392 (3)
C3—O31.208 (4)C6—H60.95
C3—C3A1.468 (3)C7—C7A1.385 (3)
C3A—C41.388 (3)C7—H70.95
C3A—C7A1.400 (3)
C2—N1—C7A111.6 (2)C5—C4—H4121.2
C2—N1—H1124.2C6—C5—C4120.5 (2)
C7A—N1—H1124.2C6—C5—I5119.00 (17)
O2—C2—N1128.6 (2)C4—C5—I5120.50 (18)
O2—C2—C3125.9 (2)C5—C6—C7122.3 (2)
N1—C2—C3105.5 (2)C5—C6—H6118.8
O3—C3—C3A130.6 (2)C7—C6—H6118.8
O3—C3—C2124.4 (2)C7A—C7—C6117.0 (2)
C3A—C3—C2105.1 (2)C7A—C7—H7121.5
C4—C3A—C7A121.6 (2)C6—C7—H7121.5
C4—C3A—C3131.7 (2)C7—C7A—C3A121.1 (2)
C7A—C3A—C3106.7 (2)C7—C7A—N1127.8 (2)
C3A—C4—C5117.5 (2)C3A—C7A—N1111.1 (2)
C3A—C4—H4121.2
C7A—N1—C2—O2176.5 (3)C3A—C4—C5—I5176.90 (18)
C7A—N1—C2—C3−2.4 (3)C4—C5—C6—C70.8 (4)
O2—C2—C3—O32.7 (4)I5—C5—C6—C7−177.37 (19)
N1—C2—C3—O3−178.4 (2)C5—C6—C7—C7A0.5 (4)
O2—C2—C3—C3A−176.4 (3)C6—C7—C7A—C3A−1.4 (4)
N1—C2—C3—C3A2.6 (2)C6—C7—C7A—N1177.1 (3)
O3—C3—C3A—C4−2.7 (5)C4—C3A—C7A—C70.9 (4)
C2—C3—C3A—C4176.3 (3)C3—C3A—C7A—C7179.2 (2)
O3—C3—C3A—C7A179.2 (2)C4—C3A—C7A—N1−177.8 (2)
C2—C3—C3A—C7A−1.8 (2)C3—C3A—C7A—N10.5 (3)
C7A—C3A—C4—C50.4 (4)C2—N1—C7A—C7−177.3 (2)
C3—C3A—C4—C5−177.4 (2)C2—N1—C7A—C3A1.3 (3)
C3A—C4—C5—C6−1.2 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O3i0.882.022.892 (3)170
C7—H7···O2i0.952.353.278 (3)164
Symmetry code: (i) −x+2, y−1/2, −z+3/2.
(II) 7-trifluoromethyl-1H-indole-2,3-dione top
Crystal data top
C9H4F3NO2F(000) = 432
Mr = 215.13Dx = 1.721 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1893 reflections
a = 5.1704 (2) Åθ = 4.0–27.5°
b = 15.5609 (11) ŵ = 0.17 mm−1
c = 10.5780 (7) ÅT = 120 K
β = 102.713 (4)°Plate, yellow
V = 830.20 (9) Å30.35 × 0.15 × 0.02 mm
Z = 4
Data collection top
Bruker–Nonius KappaCCD
diffractometer		1893 independent reflections
Radiation source: Bruker–Nonius FR591 rotating anode1412 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.037
Detector resolution: 9.091 pixels mm-1θmax = 27.5°, θmin = 4.0°
ϕ and ω scansh = −6→6
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		k = −18→20
Tmin = 0.934, Tmax = 0.997l = −13→13
9284 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)] = 0.041Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.105H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0465P)2 + 0.3729P]
where P = (Fo2 + 2Fc2)/3
1893 reflections(Δ/σ)max < 0.001
137 parametersΔρmax = 0.29 e Å−3
0 restraintsΔρmin = −0.26 e Å−3
Crystal data top
C9H4F3NO2V = 830.20 (9) Å3
Mr = 215.13Z = 4
Monoclinic, P21/cMo Kα radiation
a = 5.1704 (2) ŵ = 0.17 mm−1
b = 15.5609 (11) ÅT = 120 K
c = 10.5780 (7) Å0.35 × 0.15 × 0.02 mm
β = 102.713 (4)°
Data collection top
Bruker–Nonius KappaCCD
diffractometer		1893 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		1412 reflections with I > 2σ(I)
Tmin = 0.934, Tmax = 0.997Rint = 0.037
9284 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0410 restraints
wR(F2) = 0.105H-atom parameters constrained
S = 1.04Δρmax = 0.29 e Å−3
1893 reflectionsΔρmin = −0.26 e Å−3
137 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
N10.3672 (3)0.41319 (9)0.58953 (14)0.0247 (3)
C20.5015 (3)0.37017 (11)0.51217 (16)0.0241 (4)
O20.6305 (3)0.40066 (8)0.43947 (12)0.0297 (3)
C30.4568 (3)0.27249 (11)0.53387 (16)0.0238 (4)
O30.5537 (3)0.21499 (8)0.48362 (13)0.0314 (3)
C3A0.2815 (3)0.27031 (11)0.62630 (16)0.0231 (4)
C40.1682 (4)0.20243 (11)0.67924 (18)0.0275 (4)
C50.0043 (4)0.22067 (12)0.76393 (18)0.0297 (4)
C6−0.0380 (3)0.30540 (12)0.79553 (17)0.0267 (4)
C70.0772 (3)0.37402 (11)0.74381 (16)0.0230 (4)
C710.0352 (4)0.46486 (12)0.78114 (18)0.0293 (4)
F71−0.1323 (3)0.47130 (8)0.85986 (13)0.0521 (4)
F720.2598 (2)0.50350 (8)0.83885 (13)0.0511 (4)
F73−0.0669 (2)0.51364 (7)0.67699 (11)0.0389 (3)
C7A0.2354 (3)0.35583 (10)0.65696 (16)0.0218 (4)
H10.36320.46950.59650.046 (6)*
H40.20170.14470.65820.033*
H5−0.07860.17520.80010.036*
H6−0.14890.31690.85420.032*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0319 (8)0.0174 (7)0.0306 (8)−0.0022 (6)0.0191 (6)0.0002 (6)
C20.0261 (9)0.0220 (9)0.0268 (9)−0.0010 (7)0.0116 (7)0.0003 (7)
O20.0361 (7)0.0254 (7)0.0351 (7)−0.0033 (5)0.0237 (6)0.0005 (5)
C30.0246 (9)0.0226 (9)0.0265 (9)0.0000 (7)0.0107 (7)0.0003 (7)
O30.0366 (7)0.0270 (7)0.0353 (7)0.0037 (5)0.0179 (6)−0.0030 (5)
C3A0.0254 (9)0.0207 (9)0.0257 (9)0.0003 (6)0.0110 (7)0.0018 (7)
C40.0323 (10)0.0190 (9)0.0338 (9)0.0011 (7)0.0135 (7)0.0026 (7)
C50.0316 (10)0.0268 (9)0.0338 (10)−0.0032 (7)0.0142 (8)0.0081 (8)
C60.0263 (9)0.0300 (10)0.0277 (9)0.0012 (7)0.0143 (7)0.0045 (7)
C70.0249 (9)0.0223 (9)0.0249 (8)0.0020 (6)0.0119 (7)0.0007 (7)
C710.0331 (10)0.0285 (10)0.0316 (10)0.0005 (7)0.0185 (8)−0.0013 (8)
F710.0757 (9)0.0365 (7)0.0624 (8)0.0061 (6)0.0549 (7)−0.0026 (6)
F720.0464 (8)0.0383 (7)0.0654 (9)−0.0029 (6)0.0050 (6)−0.0205 (6)
F730.0528 (7)0.0229 (6)0.0437 (7)0.0070 (5)0.0165 (5)0.0037 (5)
C7A0.0221 (8)0.0208 (9)0.0249 (8)−0.0002 (6)0.0106 (7)0.0030 (7)
Geometric parameters (Å, º) top
N1—C21.360 (2)C4—H40.95
N1—C7A1.408 (2)C5—C61.389 (3)
N1—H10.88C5—H50.95
C2—O21.219 (2)C6—C71.392 (2)
C2—C31.562 (2)C6—H60.95
C3—O31.205 (2)C7—C7A1.387 (2)
C3—C3A1.473 (2)C7—C711.496 (2)
C3A—C41.384 (2)C71—F721.330 (2)
C3A—C7A1.402 (2)C71—F711.3308 (19)
C4—C51.391 (2)C71—F731.346 (2)
C2—N1—C7A111.16 (14)C4—C5—H5120.0
C2—N1—H1124.4C5—C6—C7121.98 (15)
C7A—N1—H1124.4C5—C6—H6119.0
O2—C2—N1127.62 (16)C7—C6—H6119.0
O2—C2—C3126.19 (15)C7A—C7—C6118.01 (16)
N1—C2—C3106.18 (13)C7A—C7—C71120.57 (15)
O3—C3—C3A130.72 (16)C6—C7—C71121.42 (14)
O3—C3—C2124.65 (15)F72—C71—F71107.53 (15)
C3A—C3—C2104.63 (13)F72—C71—F73105.44 (15)
C4—C3A—C7A121.46 (15)F71—C71—F73106.10 (14)
C4—C3A—C3131.53 (15)F72—C71—C7112.67 (15)
C7A—C3A—C3107.01 (14)F71—C71—C7112.86 (15)
C3A—C4—C5118.47 (16)F73—C71—C7111.73 (14)
C3A—C4—H4120.8C7—C7A—C3A120.12 (15)
C5—C4—H4120.8C7—C7A—N1128.88 (15)
C6—C5—C4119.93 (16)C3A—C7A—N1111.00 (14)
C6—C5—H5120.0
C7A—N1—C2—O2178.32 (17)C7A—C7—C71—F72−61.3 (2)
C7A—N1—C2—C3−1.30 (19)C6—C7—C71—F72118.12 (18)
O2—C2—C3—O32.7 (3)C7A—C7—C71—F71176.71 (16)
N1—C2—C3—O3−177.70 (16)C6—C7—C71—F71−3.9 (2)
O2—C2—C3—C3A−178.05 (17)C7A—C7—C71—F7357.2 (2)
N1—C2—C3—C3A1.58 (18)C6—C7—C71—F73−123.39 (17)
O3—C3—C3A—C4−2.7 (3)C6—C7—C7A—C3A−1.8 (2)
C2—C3—C3A—C4178.08 (19)C71—C7—C7A—C3A177.62 (16)
O3—C3—C3A—C7A177.95 (18)C6—C7—C7A—N1178.26 (17)
C2—C3—C3A—C7A−1.27 (18)C71—C7—C7A—N1−2.3 (3)
C7A—C3A—C4—C50.4 (3)C4—C3A—C7A—C71.2 (3)
C3—C3A—C4—C5−178.87 (17)C3—C3A—C7A—C7−179.40 (15)
C3A—C4—C5—C6−1.3 (3)C4—C3A—C7A—N1−178.87 (16)
C4—C5—C6—C70.7 (3)C3—C3A—C7A—N10.56 (19)
C5—C6—C7—C7A0.9 (3)C2—N1—C7A—C7−179.52 (17)
C5—C6—C7—C71−178.51 (17)C2—N1—C7A—C3A0.5 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O2i0.882.062.913 (2)164
C6—H6···O3ii0.952.333.219 (2)156
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x−1, −y+1/2, z+1/2.

Experimental details

(I)(II)
Crystal data
Chemical formulaC8H4INO2C9H4F3NO2
Mr273.02215.13
Crystal system, space groupMonoclinic, P21/cMonoclinic, P21/c
Temperature (K)120120
a, b, c (Å)9.3617 (6), 11.0930 (5), 7.6482 (4)5.1704 (2), 15.5609 (11), 10.5780 (7)
β (°) 101.146 (2) 102.713 (4)
V (Å3)779.28 (7)830.20 (9)
Z44
Radiation typeMo KαMo Kα
µ (mm−1)4.060.17
Crystal size (mm)0.48 × 0.42 × 0.220.35 × 0.15 × 0.02
Data collection
DiffractometerBruker–Nonius KappaCCD
diffractometer		Bruker–Nonius KappaCCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2003)		Multi-scan
(SADABS; Sheldrick, 2003)
Tmin, Tmax0.142, 0.4080.934, 0.997
No. of measured, independent and
observed [I > 2σ(I)] reflections		8625, 1778, 1623 9284, 1893, 1412
Rint0.0310.037
(sin θ/λ)max (Å−1)0.6500.651
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.020, 0.051, 1.09 0.041, 0.105, 1.04
No. of reflections17781893
No. of parameters97137
H-atom treatmentH-atom parameters constrainedH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.74, −0.970.29, −0.26

Computer programs: COLLECT (Hooft, 1999), DENZO (Otwinowski & Minor, 1997) and COLLECT, DENZO and COLLECT, OSCAIL (McArdle, 2003) and SHELXS97 (Sheldrick, 1997), OSCAIL and SHELXL97 (Sheldrick, 1997), PLATON (Spek, 2003), SHELXL97 and PRPKAPPA (Ferguson, 1999).

Hydrogen-bond geometry (Å, º) for (I) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O3i0.882.022.892 (3)170
C7—H7···O2i0.952.353.278 (3)164
Symmetry code: (i) −x+2, y−1/2, −z+3/2.
Hydrogen-bond geometry (Å, º) for (II) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O2i0.882.062.913 (2)164
C6—H6···O3ii0.952.333.219 (2)156
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x−1, −y+1/2, z+1/2.
Selected bond distances (Å) for compounds (I) and (II) top
Parameter(I)(II)
N1—C21.356 (3)1.360 (2)
C2—C31.565 (3)1.562 (2)
C3—C3A1.468 (3)1.473 (2)
C3A—C7A1.400 (3)1.402 (2)
C7A—N11.405 (3)1.408 (2)
C2—O21.210 (3)1.219 (2)
C3—O31.208 (4)1.205 (2)
C5—I52.101 (2)
C7—C711.496 (2)
 

Acknowledgements

X-ray data were collected at the EPSRC X-ray Crystallographic Service, University of Southampton, England; the authors thank the staff of the Service for all their help and advice. JLW thanks CNPq and FAPERJ for financial support.

References

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Journal logoSTRUCTURAL
CHEMISTRY
ISSN: 2053-2296
Volume 62| Part 6| June 2006| Pages o321-o323
doi:10.1107/S0108270106014284
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