Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536805042030/rz6147sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536805042030/rz6147Isup2.hkl |
CCDC reference: 296724
A mixture of chloral hydrate (90 g, 0.54 mol) in water (1200 ml), sodium sulfate (1300 g), aniline (46.5 g, 0.5 mol) in water (300 ml), hydrochloric acid (43 ml, 0.52 mol) and hydroxylamine hydrochloride (110 g, 1.58 mol) was heated to boiling. After two minutes of vigorous boiling, the reaction was complete. The mixture was cooled to room temperature and the solid collected by vacuum filtration to give the title compound (yield 82%). Single crystals suitable for X-ray analysis were obtained by slow evaporation of an ethanol solution.
Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); 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, 1997); software used to prepare material for publication: SHELXTL.
C8H8N2O2 | Dx = 1.394 Mg m−3 |
Mr = 164.16 | Melting point: 448K K |
Orthorhombic, Pbca | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ac 2ab | Cell parameters from 2586 reflections |
a = 9.6551 (11) Å | θ = 4.6–49.5° |
b = 9.1665 (10) Å | µ = 0.10 mm−1 |
c = 17.673 (2) Å | T = 293 K |
V = 1564.1 (3) Å3 | Block, colourless |
Z = 8 | 0.51 × 0.47 × 0.33 mm |
F(000) = 688 |
Bruker SMART CCD area-detector diffractometer | 1710 independent reflections |
Radiation source: fine-focus sealed tube | 1316 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.115 |
ϕ and ω scans | θmax = 27.0°, θmin = 2.3° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −9→12 |
Tmin = 0.764, Tmax = 0.970 | k = −11→11 |
8540 measured reflections | l = −22→20 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.048 | All H-atom parameters refined |
wR(F2) = 0.139 | w = 1/[σ2(Fo2) + (0.087P)2] where P = (Fo2 + 2Fc2)/3 |
S = 0.99 | (Δ/σ)max < 0.001 |
1710 reflections | Δρmax = 0.24 e Å−3 |
142 parameters | Δρmin = −0.21 e Å−3 |
0 restraints | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.014 (4) |
C8H8N2O2 | V = 1564.1 (3) Å3 |
Mr = 164.16 | Z = 8 |
Orthorhombic, Pbca | Mo Kα radiation |
a = 9.6551 (11) Å | µ = 0.10 mm−1 |
b = 9.1665 (10) Å | T = 293 K |
c = 17.673 (2) Å | 0.51 × 0.47 × 0.33 mm |
Bruker SMART CCD area-detector diffractometer | 1710 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 1316 reflections with I > 2σ(I) |
Tmin = 0.764, Tmax = 0.970 | Rint = 0.115 |
8540 measured reflections |
R[F2 > 2σ(F2)] = 0.048 | 0 restraints |
wR(F2) = 0.139 | All H-atom parameters refined |
S = 0.99 | Δρmax = 0.24 e Å−3 |
1710 reflections | Δρmin = −0.21 e Å−3 |
142 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.66161 (12) | 1.18186 (11) | 0.42893 (7) | 0.0573 (4) | |
O2 | 0.95936 (13) | 1.11072 (14) | 0.58949 (7) | 0.0622 (4) | |
N1 | 0.62442 (14) | 0.93660 (13) | 0.43406 (7) | 0.0483 (4) | |
N2 | 0.86575 (13) | 1.14534 (13) | 0.53268 (7) | 0.0476 (4) | |
C1 | 0.52623 (14) | 0.91247 (15) | 0.37619 (8) | 0.0444 (4) | |
C2 | 0.48807 (19) | 1.01550 (19) | 0.32307 (9) | 0.0587 (5) | |
C3 | 0.3919 (2) | 0.9790 (2) | 0.26803 (10) | 0.0671 (5) | |
C4 | 0.3332 (2) | 0.8436 (2) | 0.26599 (11) | 0.0689 (5) | |
C5 | 0.3729 (2) | 0.7405 (2) | 0.31822 (10) | 0.0693 (5) | |
C6 | 0.46916 (17) | 0.77368 (19) | 0.37263 (9) | 0.0562 (4) | |
C7 | 0.68479 (14) | 1.06102 (14) | 0.45590 (8) | 0.0437 (4) | |
C8 | 0.78712 (16) | 1.03994 (16) | 0.51731 (8) | 0.0477 (4) | |
H1 | 0.6532 (18) | 0.854 (2) | 0.4560 (11) | 0.063 (5)* | |
H2 | 0.5335 (16) | 1.105 (2) | 0.3234 (10) | 0.059 (5)* | |
H3 | 0.3719 (18) | 1.049 (2) | 0.2317 (11) | 0.072 (5)* | |
H4 | 0.266 (2) | 0.816 (2) | 0.2313 (12) | 0.083 (6)* | |
H5 | 0.327 (2) | 0.647 (2) | 0.3169 (13) | 0.088 (7)* | |
H6 | 0.505 (2) | 0.700 (2) | 0.4115 (12) | 0.072 (5)* | |
H8 | 0.7932 (17) | 0.9489 (18) | 0.5438 (10) | 0.056 (4)* | |
H2A | 1.016 (2) | 1.190 (3) | 0.5903 (13) | 0.087 (7)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0656 (7) | 0.0376 (6) | 0.0687 (8) | 0.0014 (5) | −0.0066 (5) | 0.0095 (5) |
O2 | 0.0683 (8) | 0.0565 (7) | 0.0617 (8) | −0.0098 (6) | −0.0144 (6) | 0.0052 (5) |
N1 | 0.0613 (8) | 0.0350 (7) | 0.0485 (7) | 0.0011 (5) | −0.0050 (6) | 0.0040 (5) |
N2 | 0.0559 (8) | 0.0427 (7) | 0.0441 (7) | −0.0005 (5) | 0.0022 (5) | 0.0002 (5) |
C1 | 0.0502 (8) | 0.0434 (8) | 0.0397 (8) | 0.0029 (6) | 0.0047 (6) | −0.0027 (6) |
C2 | 0.0804 (12) | 0.0465 (9) | 0.0490 (9) | 0.0068 (8) | −0.0045 (8) | 0.0020 (7) |
C3 | 0.0882 (13) | 0.0664 (11) | 0.0466 (10) | 0.0204 (10) | −0.0083 (9) | 0.0006 (8) |
C4 | 0.0700 (11) | 0.0840 (14) | 0.0525 (10) | 0.0047 (10) | −0.0115 (9) | −0.0101 (9) |
C5 | 0.0800 (12) | 0.0710 (12) | 0.0569 (10) | −0.0177 (10) | −0.0103 (9) | −0.0011 (9) |
C6 | 0.0654 (11) | 0.0546 (9) | 0.0487 (9) | −0.0082 (7) | −0.0045 (7) | 0.0042 (7) |
C7 | 0.0490 (8) | 0.0362 (7) | 0.0459 (8) | 0.0010 (6) | 0.0073 (6) | 0.0016 (6) |
C8 | 0.0573 (9) | 0.0363 (8) | 0.0496 (9) | −0.0010 (6) | 0.0021 (7) | 0.0035 (6) |
O1—C7 | 1.2265 (17) | C2—H2 | 0.930 (18) |
O2—N2 | 1.3876 (17) | C3—C4 | 1.364 (3) |
O2—H2A | 0.91 (2) | C3—H3 | 0.93 (2) |
N1—C7 | 1.3377 (18) | C4—C5 | 1.375 (3) |
N1—C1 | 1.4120 (19) | C4—H4 | 0.93 (2) |
N1—H1 | 0.89 (2) | C5—C6 | 1.372 (2) |
N2—C8 | 1.2584 (19) | C5—H5 | 0.96 (2) |
C1—C2 | 1.382 (2) | C6—H6 | 1.02 (2) |
C1—C6 | 1.388 (2) | C7—C8 | 1.480 (2) |
C2—C3 | 1.386 (2) | C8—H8 | 0.958 (17) |
N2—O2—H2A | 102.7 (15) | C3—C4—H4 | 123.6 (13) |
C7—N1—C1 | 129.43 (13) | C5—C4—H4 | 116.9 (13) |
C7—N1—H1 | 117.4 (12) | C6—C5—C4 | 120.46 (19) |
C1—N1—H1 | 113.0 (12) | C6—C5—H5 | 121.6 (14) |
C8—N2—O2 | 111.93 (12) | C4—C5—H5 | 117.9 (14) |
C2—C1—C6 | 119.34 (15) | C5—C6—C1 | 120.27 (16) |
C2—C1—N1 | 124.34 (14) | C5—C6—H6 | 123.6 (12) |
C6—C1—N1 | 116.30 (13) | C1—C6—H6 | 116.1 (12) |
C1—C2—C3 | 119.36 (17) | O1—C7—N1 | 125.34 (14) |
C1—C2—H2 | 118.3 (11) | O1—C7—C8 | 121.64 (13) |
C3—C2—H2 | 122.2 (11) | N1—C7—C8 | 113.02 (12) |
C4—C3—C2 | 121.10 (18) | N2—C8—C7 | 117.43 (13) |
C4—C3—H3 | 121.8 (12) | N2—C8—H8 | 121.8 (10) |
C2—C3—H3 | 117.1 (12) | C7—C8—H8 | 120.8 (10) |
C3—C4—C5 | 119.44 (18) | ||
C7—N1—C1—C2 | 9.6 (3) | C2—C1—C6—C5 | −1.9 (2) |
C7—N1—C1—C6 | −172.32 (15) | N1—C1—C6—C5 | 179.98 (15) |
C6—C1—C2—C3 | 1.0 (2) | C1—N1—C7—O1 | 1.7 (3) |
N1—C1—C2—C3 | 179.05 (15) | C1—N1—C7—C8 | −177.72 (14) |
C1—C2—C3—C4 | 0.7 (3) | O2—N2—C8—C7 | −178.22 (12) |
C2—C3—C4—C5 | −1.7 (3) | O1—C7—C8—N2 | −11.3 (2) |
C3—C4—C5—C6 | 0.9 (3) | N1—C7—C8—N2 | 168.19 (13) |
C4—C5—C6—C1 | 0.9 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2A···O1i | 0.91 (2) | 1.86 (3) | 2.7448 (17) | 163 (2) |
N1—H1···O1ii | 0.89 (2) | 2.434 (18) | 3.1191 (17) | 133.9 (15) |
N1—H1···N2ii | 0.89 (2) | 2.35 (2) | 3.1898 (17) | 156.0 (15) |
Symmetry codes: (i) x+1/2, −y+5/2, −z+1; (ii) −x+3/2, y−1/2, z. |
Experimental details
Crystal data | |
Chemical formula | C8H8N2O2 |
Mr | 164.16 |
Crystal system, space group | Orthorhombic, Pbca |
Temperature (K) | 293 |
a, b, c (Å) | 9.6551 (11), 9.1665 (10), 17.673 (2) |
V (Å3) | 1564.1 (3) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.51 × 0.47 × 0.33 |
Data collection | |
Diffractometer | Bruker SMART CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.764, 0.970 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 8540, 1710, 1316 |
Rint | 0.115 |
(sin θ/λ)max (Å−1) | 0.639 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.048, 0.139, 0.99 |
No. of reflections | 1710 |
No. of parameters | 142 |
H-atom treatment | All H-atom parameters refined |
Δρmax, Δρmin (e Å−3) | 0.24, −0.21 |
Computer programs: SMART (Bruker, 1997), SAINT (Bruker, 1997), SAINT, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL (Bruker, 1997), SHELXTL.
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2A···O1i | 0.91 (2) | 1.86 (3) | 2.7448 (17) | 163 (2) |
N1—H1···O1ii | 0.89 (2) | 2.434 (18) | 3.1191 (17) | 133.9 (15) |
N1—H1···N2ii | 0.89 (2) | 2.35 (2) | 3.1898 (17) | 156.0 (15) |
Symmetry codes: (i) x+1/2, −y+5/2, −z+1; (ii) −x+3/2, y−1/2, z. |
The title compound, (I), is a key intermediate in the synthesis of oxindole (Marvel & Hiers, 1941). The molecular structure of (I) is illustrated in Fig. 1. The molecule is roughly planar, the largest deviation from the mean plane being 0.224 (2) Å for atom C3. Bond lengths and angles are within normal ranges (Allen et al., 1987). The values of the N1—C7 [1.338 (2) Å] and O1—C7 [1.226(2 Å] bond lengths suggest partial sp2 character of the N atom. In the crystal structure (Fig. 2), the molecules are linked by intermolecular O—H···O, N—H···O and N—H···N hydrogen-bonding interactions (Table 1).