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

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ISSN: 2056-9890

3-Hydr­­oxy-3-[(2-methyl­propano­yl)meth­yl]indolin-2-one

aCollege of Chemistry and Chemical Engineering, Xi'an Shiyou University, Dianzi'er Road No. 18 Xi'an 710065, Xi'an, People's Republic of China, and bCollege of Environment and Chemical Engineering, Xi'an Polytechnic University, Nouth Jinhua Roud No. 19 Xi'an 710048, Xi'an, People's Republic of China
*Correspondence e-mail: gangchen@xsyu.edu.cn

(Received 26 November 2008; accepted 26 June 2009; online 1 July 2009)

The title compound, C13H15NO3, was synthesized by the Aldol reaction of isatin and 3-methyl­butan-2-one refluxing in methanol catalyzed by dimethyl­amine. The packing of the mol­ecules in the crystal structure features inter­molecular N—H⋯O and O—H⋯O hydrogen bonds.

Related literature

For related structures, see: Garden et al. (2002[Garden, S. J., da Silva, R. B. & Pinto, A. C. (2002). Tetrahedron, 58, 8399-8412.]); Li, et al. (2008[Li, Y. M., Zhang, Z. K., Jia, Y. T., Shen, Y. M., He, H. P., Fang, R. X., Chen, X. Y. & Hao, X. J. (2008). Plant Biotechnol. J. 6, 301-308.]). For the bioactivity of derivatives, see: Glover et al. (1988[Glover, V., Halket, J. M., Watkins, P. J., Clow, A., Goodwin, B. L. & Sandler, M. (1988). J. Neurochem. 51, 656-659.]); Marti & Carreira (2003[Marti, C. & Carreira, E. M. (2003). Eur. J. Org. Chem. pp. 2209-2219.]); Pandeya et al. (2000[Pandeya, S. N., Sriram, D., Nath, G. & DeClercq, E. (2000). Eur. J. Med. Chem. 35, 249-255.]); Sun et al. (1998[Sun, L., Tran, N., Tang, F., App, H., Hirth, P., McMahon, G. & Tang, C. (1998). J. Med. Chem. 41, 2588-2603.]); Teitz et al. (1994[Teitz, Y., Ronen, D., Vansover, A., Stematsky, T. & Riggs, J. L. (1994). Antivir. Res. 24, 305-314.]).

[Scheme 1]

Experimental

Crystal data
  • C13H15NO3

  • Mr = 233.26

  • Monoclinic, P 21 /c

  • a = 11.885 (2) Å

  • b = 5.9244 (12) Å

  • c = 16.695 (3) Å

  • β = 98.60 (3)°

  • V = 1162.3 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 293 K

  • 0.23 × 0.18 × 0.15 mm

Data collection
  • Bruker SMART CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2005[Sheldrick, G. M. (2005). SADABS. University of Göttingen, Germany.]) Tmin = 0.945, Tmax = 0.985

  • 8623 measured reflections

  • 2577 independent reflections

  • 1902 reflections with I > 2σ(I)

  • Rint = 0.028

Refinement
  • R[F2 > 2σ(F2)] = 0.045

  • wR(F2) = 0.161

  • S = 1.09

  • 2577 reflections

  • 155 parameters

  • H-atom parameters constrained

  • Δρmax = 0.24 e Å−3

  • Δρmin = −0.22 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1A⋯O2i 0.86 2.22 3.0049 (18) 151
O2—H2A⋯O1ii 0.82 2.00 2.8220 (17) 175
Symmetry codes: (i) x, y+1, z; (ii) -x+1, -y+1, -z+1.

Data collection: SMART (Bruker, 2002[Bruker (2002). SMART and SAINT for WNT/2000. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2002[Bruker (2002). SMART and SAINT for WNT/2000. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and DIAMOND (Brandenburg, 1999[Brandenburg, K. (1999). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information


Comment top

Isatin, an endogenous compound in mammalian tissues and body fluids (Glover, et al., 1988), has caught great attention of many researchers as a versatile lead molecule for designing of potential drugs (Pandeya, et al., 2000; Sun, et al., 1998; Teitz, et al., 1994). In our previous study, 3-hydroxy-3-(2-oxo-propyl)-1,3-dihydro-indol-2-one, yielded from the Aldol reaction of isatin with acetone, was found to be a new chemical activator against tobacco mosaic virus (TMV) infection (Li, 2008). In tobacco plant, external application of 3-hydroxy-3-(2-oxo-propyl)-1,3-dihydro-indol-2-one results in restriction of TMV multiplication and spread, accumulation of salicylic acid level expression of PR-1 gene, and activation and increase of phenylalanine ammonia-lyase (PAL) activity. With these findings, some analogs need to be synthesized for structure activity relationship research to find more potent molecules.

One of these analogs, 3-hydroxy-3-(3-methyl-2-oxo-butyl)-1,3-dihydro-indol-2-one (compound I), was synthesized by the Aldol reaction of isatin with 3-methyl-butan-2-one. In order to provide the structural information of compound I, we studied its crystal structure. The title compound was synthesized in a one step Aldol reaction of isatin (0.01 mmol) with 3-methyl-butan-2-one, according to the reported method (Garden et al., 2002). The molar ratio of isatin: 3-methyl-butan-2-one = 1:3 refluxed in methanol gave compound I in 72% yield, and colorless crystals of compound I were obtained in ethanol by recrystallization. The values of the geometric parameters of compound I are within normal ranges and experimental errors.

The molecular structure of compound I is illustrated in Fig. 1. In the molecule, the 2-oxo-indole ring is planar, and the angle between hydroxyl group and 3-methyl-2-oxo-butyl group is 105.10 (12)°. The intermolecular interactions are primarily responsible for the formation of the crystal structure of compound I. Each molecule is fixed by four hydrogen bond of other three molecules. N1–H1 acts as a hydrogen bond donor, and O1 is a hydrogen bond accepter. To O2–H2, it acts as both a hydrogen bond donor and a hydrogen bond accepter, which connects with two molecules by O–H···O and O···H–N with the angle of 119.21 (9)°. There is no anticipated intramolecular hydrogen bond between O2–H2 and O3, and O3 is not involved in any hydrogen bond (Fig. 2).

Related literature top

For related structures, see: Garden et al. (2002); Li, et al. (2008). For the bioactivity of derivatives, see: Glover et al. (1988); Marti & Carreira (2003); Pandeya et al. (2000); Sun et al. (1998); Teitz et al. (1994).

For related literature, see: Brandenburg (1999).

Experimental top

A mixture of isatin (0.01 mmol) and 3-methyl-butan-2-one (0.03 mmol) was refluxed in methanol (60 ml), catalyzed by a drop of dimethylamine, until the disappearance of the starting material, as evidenced by thin-layer chromatography. The solvent was removed in vacuo and the residue was separated by column chromatography (silica gel, petroleum ether/ethyl acetate = 5:1), giving the title compound I 0.168 g, yield 72%. 1H-NMR (CDCl3, 400 MHz): 8.5 (1H,s), 7.32 (1H, d, J = 7.2 Hz), 7.24 (1H, t, J = 7.6 Hz), 7.03 (1H, t, J = 7.2 Hz), 6.88 (1H, d, J = 16.8 Hz), 4.81 (1H, s), 3.25 (1H, d, J = 16.8 Hz), 3.17 (1H, d, J = 16.8 Hz), 2.56 (1H, q, J = 6.8 Hz), 1.05 (6H, dd, J = 29.2, 6.8 Hz); 13C-NMR (CDCl3, 100 MHz): 213.9, 178.5, 140.6, 130.3, 129.9, 124.1, 123.1, 110.5, 74.7, 45.6, 41.9, 17.6; MS (EI) m/z: 219 (M+). 30 mg of compound I was dissolved in 30 ml methanol and the solution was kept at room temperature for 4 d, natural evaporation gave colorless single crystals of compound I suitable for X-ray analysis.

Refinement top

All H atoms were positioned geometrically, with C–H = 0.93–0.98 Å, and refined using riding model, with Uiso(H) = 1.2Ueq(carrier).

Computing details top

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 1999); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. An ORTEP-3 drawing of compound I, with the atom-numbering scheme and 30% probability displacement ellipsoids.
[Figure 2] Fig. 2. Packing diagram of the title compound. Dashed lines indicate hydrogen bonds.
3-Hydroxy-3-[(2-methylpropanoyl)methyl]indolin-2-one top
Crystal data top
C13H15NO3F(000) = 496
Mr = 233.26Dx = 1.333 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3113 reflections
a = 11.885 (2) Åθ = 1.9–27.4°
b = 5.9244 (12) ŵ = 0.10 mm1
c = 16.695 (3) ÅT = 293 K
β = 98.60 (3)°Block, colorless
V = 1162.3 (5) Å30.23 × 0.18 × 0.15 mm
Z = 4
Data collection top
Bruker SMART CCD area-detector
diffractometer
2577 independent reflections
Radiation source: fine-focus sealed tube1902 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.028
ϕ and ω scansθmax = 27.5°, θmin = 1.7°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2005)
h = 1514
Tmin = 0.945, Tmax = 0.985k = 77
8623 measured reflectionsl = 2115
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.045H-atom parameters constrained
wR(F2) = 0.161 w = 1/[σ2(Fo2) + (0.0562P)2 + 0.2707P]
where P = (Fo2 + 2Fc2)/3
S = 1.09(Δ/σ)max < 0.001
2577 reflectionsΔρmax = 0.24 e Å3
155 parametersΔρmin = 0.22 e Å3
0 restraintsExtinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4'
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.018 (4)
Crystal data top
C13H15NO3V = 1162.3 (5) Å3
Mr = 233.26Z = 4
Monoclinic, P21/cMo Kα radiation
a = 11.885 (2) ŵ = 0.10 mm1
b = 5.9244 (12) ÅT = 293 K
c = 16.695 (3) Å0.23 × 0.18 × 0.15 mm
β = 98.60 (3)°
Data collection top
Bruker SMART CCD area-detector
diffractometer
2577 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2005)
1902 reflections with I > 2σ(I)
Tmin = 0.945, Tmax = 0.985Rint = 0.028
8623 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0450 restraints
wR(F2) = 0.161H-atom parameters constrained
S = 1.09Δρmax = 0.24 e Å3
2577 reflectionsΔρmin = 0.22 e Å3
155 parameters
Special details top

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 (Å2) top
xyzUiso*/Ueq
O20.57929 (9)0.14669 (16)0.55228 (6)0.0335 (3)
H2A0.51830.21280.54110.050*
O10.62325 (9)0.59992 (19)0.48205 (6)0.0368 (3)
N10.60709 (11)0.6720 (2)0.61556 (8)0.0324 (3)
H1A0.58300.80880.61030.039*
O30.87069 (11)0.5445 (2)0.61665 (9)0.0542 (4)
C10.63221 (12)0.5435 (2)0.55343 (9)0.0292 (4)
C80.66420 (12)0.3373 (2)0.67659 (9)0.0278 (4)
C90.77543 (13)0.2149 (3)0.56337 (10)0.0320 (4)
H9A0.78680.06110.58290.038*
H9B0.76790.21050.50470.038*
C100.87990 (14)0.3519 (3)0.59554 (10)0.0347 (4)
C70.62536 (13)0.5539 (2)0.69000 (9)0.0289 (4)
C20.66509 (12)0.3034 (2)0.58702 (9)0.0276 (4)
C30.69101 (13)0.1899 (3)0.74041 (9)0.0322 (4)
H3A0.71850.04620.73200.039*
C60.61006 (14)0.6260 (3)0.76617 (10)0.0351 (4)
H6A0.58320.77020.77460.042*
C40.67614 (14)0.2602 (3)0.81790 (10)0.0383 (4)
H4A0.69310.16210.86150.046*
C50.63660 (14)0.4736 (3)0.83018 (10)0.0381 (4)
H5A0.62730.51760.88230.046*
C110.99369 (15)0.2365 (3)0.59805 (12)0.0500 (5)
H11A0.99320.15390.54710.060*
C121.0100 (2)0.0663 (4)0.66754 (18)0.0843 (9)
H12A0.94720.03750.66140.126*
H12B1.01330.14460.71820.126*
H12C1.07960.01530.66670.126*
C131.09104 (19)0.4058 (5)0.60623 (16)0.0752 (7)
H13A1.07970.50890.56140.113*
H13B1.16170.32710.60650.113*
H13C1.09310.48800.65600.113*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O20.0286 (6)0.0262 (6)0.0431 (7)0.0024 (4)0.0035 (5)0.0012 (4)
O10.0390 (7)0.0385 (7)0.0323 (6)0.0007 (5)0.0031 (5)0.0073 (5)
N10.0381 (8)0.0242 (6)0.0349 (8)0.0044 (5)0.0053 (6)0.0016 (5)
O30.0401 (8)0.0400 (8)0.0817 (10)0.0055 (5)0.0068 (7)0.0124 (7)
C10.0247 (8)0.0269 (8)0.0353 (9)0.0018 (6)0.0021 (6)0.0021 (6)
C80.0247 (8)0.0271 (8)0.0317 (8)0.0010 (6)0.0044 (6)0.0004 (6)
C90.0290 (8)0.0312 (8)0.0352 (8)0.0019 (6)0.0025 (6)0.0032 (6)
C100.0325 (9)0.0390 (9)0.0334 (9)0.0020 (7)0.0074 (7)0.0007 (7)
C70.0252 (8)0.0283 (8)0.0332 (8)0.0003 (6)0.0041 (6)0.0025 (6)
C20.0263 (8)0.0253 (8)0.0300 (8)0.0016 (6)0.0002 (6)0.0015 (6)
C30.0324 (9)0.0277 (8)0.0360 (9)0.0022 (6)0.0034 (7)0.0036 (6)
C60.0346 (9)0.0301 (9)0.0415 (9)0.0009 (6)0.0085 (7)0.0054 (7)
C40.0377 (10)0.0429 (10)0.0333 (9)0.0001 (7)0.0022 (7)0.0066 (7)
C50.0340 (9)0.0512 (11)0.0298 (8)0.0023 (7)0.0071 (6)0.0045 (7)
C110.0313 (10)0.0610 (12)0.0566 (12)0.0022 (8)0.0033 (8)0.0117 (10)
C120.0569 (15)0.0593 (14)0.127 (2)0.0053 (11)0.0164 (14)0.0254 (15)
C130.0335 (12)0.1033 (19)0.0886 (18)0.0095 (12)0.0084 (11)0.0082 (15)
Geometric parameters (Å, º) top
O2—C21.4356 (16)C3—C41.395 (2)
O2—H2A0.8200C3—H3A0.9300
O1—C11.2270 (18)C6—C51.399 (2)
N1—C11.355 (2)C6—H6A0.9300
N1—C71.4144 (19)C4—C51.375 (3)
N1—H1A0.8600C4—H4A0.9300
O3—C101.204 (2)C5—H5A0.9300
C1—C21.557 (2)C11—C131.522 (3)
C8—C31.378 (2)C11—C121.527 (3)
C8—C71.393 (2)C11—H11A0.9800
C8—C21.510 (2)C12—H12A0.9600
C9—C101.513 (2)C12—H12B0.9600
C9—C21.518 (2)C12—H12C0.9600
C9—H9A0.9700C13—H13A0.9600
C9—H9B0.9700C13—H13B0.9600
C10—C111.511 (2)C13—H13C0.9600
C7—C61.379 (2)
C2—O2—H2A109.5C8—C3—H3A120.6
C1—N1—C7111.85 (12)C4—C3—H3A120.6
C1—N1—H1A124.1C7—C6—C5117.29 (15)
C7—N1—H1A124.1C7—C6—H6A121.4
O1—C1—N1126.39 (14)C5—C6—H6A121.4
O1—C1—C2125.40 (14)C5—C4—C3120.42 (15)
N1—C1—C2108.04 (13)C5—C4—H4A119.8
C3—C8—C7120.23 (14)C3—C4—H4A119.8
C3—C8—C2130.26 (14)C4—C5—C6121.53 (15)
C7—C8—C2109.47 (12)C4—C5—H5A119.2
C10—C9—C2114.65 (13)C6—C5—H5A119.2
C10—C9—H9A108.6C13—C11—C10111.69 (16)
C2—C9—H9A108.6C13—C11—C12111.02 (18)
C10—C9—H9B108.6C10—C11—C12109.35 (17)
C2—C9—H9B108.6C13—C11—H11A108.2
H9A—C9—H9B107.6C10—C11—H11A108.2
O3—C10—C11122.77 (15)C12—C11—H11A108.2
O3—C10—C9120.45 (15)C11—C12—H12A109.5
C11—C10—C9116.77 (14)C11—C12—H12B109.5
C6—C7—C8121.75 (14)H12A—C12—H12B109.5
C6—C7—N1129.26 (14)C11—C12—H12C109.5
C8—C7—N1108.99 (13)H12A—C12—H12C109.5
O2—C2—C8112.10 (12)H12B—C12—H12C109.5
O2—C2—C9105.10 (11)C11—C13—H13A109.5
C8—C2—C9115.95 (12)C11—C13—H13B109.5
O2—C2—C1108.68 (11)H13A—C13—H13B109.5
C8—C2—C1101.33 (11)C11—C13—H13C109.5
C9—C2—C1113.69 (13)H13A—C13—H13C109.5
C8—C3—C4118.76 (15)H13B—C13—H13C109.5
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O2i0.862.223.0049 (18)151
O2—H2A···O1ii0.822.002.8220 (17)175
Symmetry codes: (i) x, y+1, z; (ii) x+1, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC13H15NO3
Mr233.26
Crystal system, space groupMonoclinic, P21/c
Temperature (K)293
a, b, c (Å)11.885 (2), 5.9244 (12), 16.695 (3)
β (°) 98.60 (3)
V3)1162.3 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.23 × 0.18 × 0.15
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2005)
Tmin, Tmax0.945, 0.985
No. of measured, independent and
observed [I > 2σ(I)] reflections
8623, 2577, 1902
Rint0.028
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.045, 0.161, 1.09
No. of reflections2577
No. of parameters155
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.24, 0.22

Computer programs: SMART (Bruker, 2002), SAINT (Bruker, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 1999), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O2i0.862.223.0049 (18)151
O2—H2A···O1ii0.822.002.8220 (17)175
Symmetry codes: (i) x, y+1, z; (ii) x+1, y+1, z+1.
 

Acknowledgements

This work was supported financially by grants from the National Science Foundation of China (No. 50874092) and the Scientific Research Plan Projects of Shaanxi Education Department (08 J K 413).

References

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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
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