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

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A hydrogen-bonded chain of edge-fused rings in 5-nitro­isatin

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

(Received 15 September 2006; accepted 15 September 2006; online 22 September 2006)

The title compound, C8H4N2O4, crystallizes with Z′ = 2. The mol­ecules are linked by a combination of N—H⋯O and C—H⋯O hydrogen bonds into chains of edge-fused R44(16) and R44(26) rings.

Comment

We report here the mol­ecular and supra­molecular structure of 5-nitro­isatin (I)[link], whose behaviour is briefly compared with that of 5-iodo­isatin (II), which we reported recently (Garden et al., 2006[Garden, S. J., Pinto, A. C., Wardell, J. L., Low, J. N. & Glidewell, C. (2006). Acta Cryst. C62, o321-o323.]).

[Scheme 1]

Compound (I)[link] crystallizes with Z′ = 2 in the space group P[\overline{1}] (Fig. 1[link]), and the two mol­ecules have very similar dimensions. Both exhibit long bonds, C11—C12 and C21—C22, between the two carbonyl groups (Table 1[link]), as typically found in isatins (Palenik et al., 1990[Palenik, G. J., Koziol, A. E., Katritzky, A. R. & Fan, W.-Q. (1990). Chem. Commun. pp. 715-716.]; Garden et al., 2006[Garden, S. J., Pinto, A. C., Wardell, J. L., Low, J. N. & Glidewell, C. (2006). Acta Cryst. C62, o321-o323.]), while the dihedral angles between the nitro groups and the adjacent aryl rings are 10.4 (2)° in mol­ecule 1 and 7.4 (2)° in mol­ecule 2.

The mol­ecules are linked into chains of edge-fused rings by a combination of N—H⋯O and C—H⋯O hydrogen bonds (Table 2[link]). The N—H⋯O hydrogen bonds link groups of four mol­ecules, two of each type, into centrosymmetric R44(16) rings (Bernstein et al., 1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]) (Fig. 2[link]), and these tetra­molecular aggregates are linked by a single C—H⋯O hydrogen bond into a chain of edge-fused rings along [001], with R44(16) rings centred at (½, ½, n + ½) (n = zero or integer) alternating with R44(26) rings centred at (½, ½, n) (n = zero or integer) (Fig. 3[link]).

These chain of rings are weakly linked by a sheared, parallel (type III, Allen et al., 1998[Allen, F. H., Baalham, C. A., Lommerse, J. P. M. & Raithby, P. R. (1998). Acta Cryst. B54, 320-329.]) carbon­yl–carbonyl inter­action. Atom O11 in the mol­ecule at (x, y, z), which lies in the chain along (½, ½, z), makes a short dipolar contact with atom C22 in the mol­ecule at (−x, 1 − y, 1 − z), which is part of the chain along (0, ½, z); the key dimensions are O11⋯·C22i = 2.835 (4) Å, O11⋯O22i = 3.266 (3) Å, C11—O11⋯C22i = 145.8 (2)° and C11—O11⋯O22i = 163.9 (2)° [symmetry code: (i) −x, 1 − y, 1 − z]. Propagation by inversion of this inter­action links the chains into sheets parallel to (010).

In 5-iodo­isatin, (II), by contrast, which crystallizes with Z′ = 1, the mol­ecules are linked by a combination of one N—H⋯O hydrogen bond, one C—H⋯O hydrogen bond and one iodo–carbonyl inter­action into sheets containing alternating columns of R22(9) and R43(16) rings, while in isatin itself, the mol­ecules are linked by paired N—H⋯O hydrogen bonds into R22(8) dimers which are themselves linked into sheets by aromatic ππ stacking inter­actions (Garden et al., 2006[Garden, S. J., Pinto, A. C., Wardell, J. L., Low, J. N. & Glidewell, C. (2006). Acta Cryst. C62, o321-o323.]).

[Figure 1]
Figure 1
The two independent mol­ecules of compound (I)[link], showing the atom-labelling scheme and the hydrogen-bond (dashed line) within the selected asymmetric unit. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2]
Figure 2
Part of the crystal structure of compound (I)[link], showing the formation of a centrosymmetric tetra­molecular aggregate built from N—H⋯O hydrogen bonds. For the sake of clarity, H atoms bonded to C atoms have been omitted. Atoms marked with an asterisk (*) are at the symmetry position (1 − x, 1 − y, 1 − z), and hydrogen bonds are shown as dashed lines
[Figure 3]
Figure 3
A stereoscopic view of part of the crystal structure of compound (I)[link], showing the formation of a chain of edge-fused R44(16) and R44(26) rings along [001]. Hydrogen bonds are shown as dashed lines, and for the sake of clarity, H atoms not involved in the motifs shown have been omitted.

Experimental

A commercial sample (Aldrich) of 5-nitro­isatin was recrystallized from ethanol.

Crystal data
  • C8H4N2O4

  • Mr = 192.13

  • Triclinic, [P \overline 1]

  • a = 5.5595 (6) Å

  • b = 12.0772 (13) Å

  • c = 12.2795 (14) Å

  • α = 87.322 (3)°

  • β = 87.355 (3)°

  • γ = 83.049 (3)°

  • V = 816.85 (16) Å3

  • Z = 4

  • Dx = 1.562 Mg m−3

  • Mo Kα radiation

  • μ = 0.13 mm−1

  • T = 291 (2) K

  • Thick plate, colourless

  • 0.28 × 0.12 × 0.07 mm

Data collection
  • Bruker SMART 1000 CCD area-detector diffractometer

  • φ and ω scans

  • Absorption correction: multi-scan (SADABS; Bruker, 2000[Bruker (2000). SMART (Version 5.624), SAINT-Plus (Version 6.02A) and SADABS (Version 2.03). Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.954, Tmax = 0.991

  • 6130 measured reflections

  • 4096 independent reflections

  • 1331 reflections with I > 2σ(I)

  • Rint = 0.040

  • θmax = 28.5°

Refinement
  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.061

  • wR(F2) = 0.109

  • S = 1.00

  • 4096 reflections

  • 253 parameters

  • H-atom parameters constrained

  • w = 1/[σ2(Fo2) + (0.0209P)2] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max < 0.001

  • Δρmax = 0.47 e Å−3

  • Δρmin = −0.17 e Å−3

Table 1
Selected geometric parameters (Å, °)

C11—C12 1.558 (4)
C21—C22 1.552 (4)
C14—C15—N15—O151 −11.5 (5)
C14—C15—N15—O152 169.8 (3)
C24—C25—N25—O251 8.0 (6)
C24—C25—N25—O252 −173.5 (4)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N11—H11⋯O21 0.86 2.11 2.888 (3) 151
N21—H21⋯O11i 0.86 2.03 2.875 (3) 168
C27—H27⋯O152ii 0.93 2.43 3.272 (4) 151
Symmetry codes: (i) -x+1, -y+1, -z+1; (ii) x, y, z-1.

All H atoms were located in difference maps and then treated as riding atoms, with C—H = 0.93 Å, N—H = 0.86 Å and Uiso(H) = 1.2Ueq(C,N).

Data collection: SMART (Bruker, 2000[Bruker (2000). SMART (Version 5.624), SAINT-Plus (Version 6.02A) and SADABS (Version 2.03). Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2000[Bruker (2000). SMART (Version 5.624), SAINT-Plus (Version 6.02A) and SADABS (Version 2.03). Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); program(s) used to refine structure: 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


Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 and PRPKAPPA (Ferguson, 1999).

5-nitroisatin top
Crystal data top
C8H4N2O4Z = 4
Mr = 192.13F(000) = 392
Triclinic, P1Dx = 1.562 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 5.5595 (6) ÅCell parameters from 4096 reflections
b = 12.0772 (13) Åθ = 2.3–28.5°
c = 12.2795 (14) ŵ = 0.13 mm1
α = 87.322 (3)°T = 291 K
β = 87.355 (3)°Plate, colourless
γ = 83.049 (3)°0.28 × 0.12 × 0.07 mm
V = 816.85 (16) Å3
Data collection top
Bruker SMART 1000 CCD area-detector
diffractometer
4096 independent reflections
Radiation source: fine-focus sealed X-ray tube1331 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.040
φ and ω scansθmax = 28.5°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Bruker, 2000)
h = 77
Tmin = 0.954, Tmax = 0.991k = 916
6130 measured reflectionsl = 1616
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)] = 0.061Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.109H-atom parameters constrained
S = 1.00 w = 1/[σ2(Fo2) + (0.0209P)2]
where P = (Fo2 + 2Fc2)/3
4096 reflections(Δ/σ)max < 0.001
253 parametersΔρmax = 0.47 e Å3
0 restraintsΔρmin = 0.17 e Å3
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
N110.3270 (4)0.52765 (19)0.6854 (2)0.0572 (7)
C110.5305 (5)0.4543 (3)0.6734 (3)0.0540 (9)
O110.5875 (3)0.39001 (17)0.60197 (17)0.0665 (6)
C120.6815 (6)0.4705 (3)0.7740 (3)0.0601 (9)
O120.8707 (4)0.41752 (17)0.79350 (18)0.0800 (7)
C130.5357 (5)0.5591 (2)0.8353 (2)0.0502 (8)
C140.5719 (5)0.6104 (3)0.9294 (2)0.0596 (9)
C150.3956 (6)0.6924 (3)0.9633 (3)0.0604 (9)
N150.4302 (7)0.7516 (3)1.0631 (3)0.0870 (10)
O1510.5978 (6)0.7118 (2)1.1205 (2)0.1182 (11)
O1520.2903 (5)0.8343 (2)1.0838 (2)0.1104 (10)
C160.1877 (6)0.7245 (3)0.9071 (3)0.0639 (9)
C170.1489 (5)0.6716 (2)0.8130 (3)0.0625 (9)
C180.3247 (5)0.5898 (2)0.7790 (2)0.0504 (8)
N210.0737 (4)0.71675 (19)0.4343 (2)0.0621 (8)
C210.1946 (6)0.6865 (3)0.5280 (3)0.0621 (9)
O210.1308 (4)0.61082 (18)0.59215 (18)0.0763 (7)
C220.4299 (6)0.7701 (3)0.5318 (3)0.0698 (10)
O220.5799 (5)0.7723 (2)0.6023 (2)0.1049 (9)
C230.4190 (5)0.8428 (2)0.4307 (2)0.0549 (8)
C240.5712 (6)0.9294 (3)0.3880 (3)0.0731 (10)
C250.5048 (7)0.9777 (3)0.2914 (4)0.0791 (11)
N250.6688 (8)1.0689 (3)0.2399 (4)0.1154 (15)
O2510.8492 (6)1.1031 (3)0.2982 (3)0.1604 (17)
O2520.6190 (6)1.1048 (3)0.1501 (3)0.1631 (17)
C260.2895 (7)0.9444 (3)0.2369 (3)0.0812 (11)
C270.1306 (6)0.8572 (3)0.2793 (3)0.0706 (10)
C280.2009 (5)0.8062 (2)0.3768 (3)0.0557 (8)
H110.21170.53520.64030.069*
H140.71060.59030.96880.072*
H160.07420.78150.93230.077*
H170.00880.69090.77440.075*
H210.06560.68430.41290.075*
H240.71670.95450.42430.088*
H260.24960.98040.17110.097*
H270.01690.83410.24370.085*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N110.0482 (17)0.0578 (17)0.0646 (19)0.0037 (13)0.0135 (13)0.0073 (14)
C110.053 (2)0.046 (2)0.064 (2)0.0084 (16)0.0050 (18)0.0027 (17)
O110.0613 (15)0.0629 (15)0.0755 (17)0.0028 (11)0.0079 (12)0.0256 (12)
C120.048 (2)0.061 (2)0.071 (2)0.0081 (17)0.0072 (18)0.0146 (18)
O120.0617 (15)0.0758 (16)0.0988 (19)0.0089 (12)0.0162 (13)0.0053 (13)
C130.050 (2)0.049 (2)0.051 (2)0.0031 (15)0.0012 (17)0.0018 (16)
C140.053 (2)0.067 (2)0.059 (2)0.0110 (17)0.0023 (18)0.0049 (18)
C150.070 (2)0.065 (2)0.051 (2)0.0243 (19)0.0047 (19)0.0083 (18)
N150.098 (3)0.092 (3)0.077 (3)0.032 (2)0.007 (2)0.019 (2)
O1510.131 (3)0.134 (3)0.099 (2)0.029 (2)0.035 (2)0.0329 (18)
O1520.118 (2)0.116 (2)0.101 (2)0.0201 (18)0.0192 (18)0.0535 (18)
C160.065 (2)0.055 (2)0.071 (3)0.0070 (17)0.008 (2)0.0085 (18)
C170.055 (2)0.062 (2)0.068 (3)0.0018 (17)0.0009 (18)0.0056 (18)
C180.050 (2)0.055 (2)0.046 (2)0.0057 (16)0.0025 (16)0.0014 (16)
N210.0507 (17)0.0605 (18)0.072 (2)0.0061 (13)0.0037 (15)0.0008 (15)
C210.057 (2)0.061 (2)0.070 (3)0.0070 (18)0.0160 (19)0.0118 (19)
O210.0721 (16)0.0747 (17)0.0816 (18)0.0048 (12)0.0245 (13)0.0130 (13)
C220.058 (2)0.084 (3)0.070 (3)0.0134 (19)0.0164 (19)0.038 (2)
O220.115 (2)0.102 (2)0.097 (2)0.0168 (16)0.0296 (17)0.0162 (15)
C230.057 (2)0.049 (2)0.058 (2)0.0044 (16)0.0006 (17)0.0028 (17)
C240.056 (2)0.051 (2)0.112 (3)0.0058 (18)0.003 (2)0.008 (2)
C250.075 (3)0.054 (2)0.110 (4)0.009 (2)0.033 (2)0.009 (2)
N250.098 (3)0.071 (3)0.180 (5)0.027 (2)0.047 (3)0.040 (3)
O2510.098 (3)0.097 (3)0.278 (5)0.005 (2)0.036 (3)0.057 (3)
O2520.188 (4)0.120 (3)0.188 (4)0.049 (2)0.085 (3)0.085 (3)
C260.107 (3)0.066 (3)0.076 (3)0.032 (2)0.018 (2)0.013 (2)
C270.068 (2)0.070 (3)0.075 (3)0.0117 (19)0.007 (2)0.008 (2)
C280.055 (2)0.053 (2)0.061 (2)0.0076 (17)0.0075 (18)0.0078 (17)
Geometric parameters (Å, º) top
N11—C111.357 (3)N21—C211.363 (4)
N11—C181.401 (3)N21—C281.399 (3)
N11—H110.86N21—H210.86
C11—O111.205 (3)C21—O211.209 (3)
C11—C121.558 (4)C21—C221.552 (4)
C12—O121.191 (3)C22—O221.173 (3)
C12—C131.476 (4)C22—C231.489 (4)
C13—C141.371 (4)C23—C241.363 (4)
C13—C181.392 (4)C23—C281.388 (4)
C14—C151.371 (4)C24—C251.353 (4)
C14—H140.93C24—H240.93
C15—C161.380 (4)C25—C261.370 (4)
C15—N151.479 (4)C25—N251.479 (4)
N15—O1521.218 (3)N25—O2521.200 (4)
N15—O1511.232 (3)N25—O2511.245 (4)
C16—C171.384 (4)C26—C271.388 (4)
C16—H160.93C26—H260.93
C17—C181.368 (3)C27—C281.383 (4)
C17—H170.93C27—H270.93
C11—N11—C18112.8 (3)C21—N21—C28112.6 (3)
C11—N11—H11123.6C21—N21—H21123.7
C18—N11—H11123.6C28—N21—H21123.7
O11—C11—N11129.0 (3)O21—C21—N21127.0 (3)
O11—C11—C12126.2 (3)O21—C21—C22128.7 (3)
N11—C11—C12104.7 (3)N21—C21—C22104.3 (3)
O12—C12—C13130.5 (3)O22—C22—C23129.2 (3)
O12—C12—C11124.4 (3)O22—C22—C21124.8 (4)
C13—C12—C11105.1 (2)C23—C22—C21106.0 (3)
C14—C13—C18120.0 (3)C24—C23—C28120.7 (3)
C14—C13—C12132.9 (3)C24—C23—C22133.6 (3)
C18—C13—C12107.1 (3)C28—C23—C22105.7 (2)
C13—C14—C15117.4 (3)C25—C24—C23118.2 (3)
C13—C14—H14121.3C25—C24—H24120.9
C15—C14—H14121.3C23—C24—H24120.9
C14—C15—C16123.0 (3)C24—C25—C26122.4 (3)
C14—C15—N15119.1 (3)C24—C25—N25120.0 (4)
C16—C15—N15117.9 (3)C26—C25—N25117.5 (4)
O152—N15—O151124.8 (4)O252—N25—O251125.8 (4)
O152—N15—C15118.4 (4)O252—N25—C25119.7 (5)
O151—N15—C15116.9 (4)O251—N25—C25114.4 (5)
C15—C16—C17119.7 (3)C25—C26—C27120.4 (3)
C15—C16—H16120.2C25—C26—H26119.8
C17—C16—H16120.2C27—C26—H26119.8
C18—C17—C16117.4 (3)C28—C27—C26117.2 (3)
C18—C17—H17121.3C28—C27—H27121.4
C16—C17—H17121.3C26—C27—H27121.4
C17—C18—C13122.5 (3)C27—C28—C23121.1 (3)
C17—C18—N11127.2 (3)C27—C28—N21127.5 (3)
C13—C18—N11110.2 (3)C23—C28—N21111.4 (3)
C18—N11—C11—O11179.5 (3)C28—N21—C21—O21178.2 (3)
C18—N11—C11—C120.4 (3)C28—N21—C21—C221.2 (3)
O11—C11—C12—O122.4 (5)O21—C21—C22—O222.3 (6)
N11—C11—C12—O12177.6 (3)N21—C21—C22—O22178.4 (3)
O11—C11—C12—C13179.2 (3)O21—C21—C22—C23178.1 (3)
N11—C11—C12—C130.8 (3)N21—C21—C22—C231.3 (3)
O12—C12—C13—C142.4 (6)O22—C22—C23—C241.2 (7)
C11—C12—C13—C14179.4 (3)C21—C22—C23—C24179.1 (4)
O12—C12—C13—C18177.5 (3)O22—C22—C23—C28178.7 (4)
C11—C12—C13—C180.8 (3)C21—C22—C23—C280.9 (4)
C18—C13—C14—C150.9 (4)C28—C23—C24—C250.6 (5)
C12—C13—C14—C15179.3 (3)C22—C23—C24—C25179.4 (4)
C13—C14—C15—C160.1 (5)C23—C24—C25—C261.4 (6)
C13—C14—C15—N15178.6 (3)C23—C24—C25—N25177.6 (3)
C14—C15—N15—O15111.5 (5)C24—C25—N25—O2518.0 (6)
C14—C15—N15—O152169.8 (3)C24—C25—N25—O252173.5 (4)
C16—C15—N15—O1528.7 (4)C26—C25—N25—O2525.5 (6)
C16—C15—N15—O151169.9 (3)C26—C25—N25—O251172.9 (4)
C14—C15—C16—C171.2 (5)C24—C25—C26—C270.8 (6)
N15—C15—C16—C17179.7 (3)N25—C25—C26—C27178.2 (3)
C15—C16—C17—C181.2 (4)C25—C26—C27—C280.6 (5)
C16—C17—C18—C130.2 (4)C26—C27—C28—C231.4 (5)
C16—C17—C18—N11178.3 (3)C26—C27—C28—N21179.3 (3)
C14—C13—C18—C170.9 (4)C24—C23—C28—C270.8 (5)
C12—C13—C18—C17179.3 (3)C22—C23—C28—C27179.1 (3)
C14—C13—C18—N11179.6 (2)C24—C23—C28—N21179.8 (3)
C12—C13—C18—N110.6 (3)C22—C23—C28—N210.3 (4)
C11—N11—C18—C17178.7 (3)C21—N21—C28—C27180.0 (3)
C11—N11—C18—C130.1 (3)C21—N21—C28—C230.6 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N11—H11···O210.862.112.888 (3)151
N21—H21···O11i0.862.032.875 (3)168
C27—H27···O152ii0.932.433.272 (4)151
Symmetry codes: (i) x+1, y+1, z+1; (ii) x, y, z1.
 

Acknowledgements

X-ray data were collected at the University of Aberdeen; the authors thank the University of Aberdeen for funding the purchase of the diffractometer. JLW thanks CNPq and FAPERJ for financial support.

References

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