supplementary materials


pv2603 scheme

Acta Cryst. (2012). E68, o3468-o3469    [ doi:10.1107/S160053681204706X ]

A triclinic polymorph of methyl (3R,3'S)-1',1''-dimethyl-2,2''-dioxodispiro[indoline-3,2'-pyrrolidine-3',3''-indoline]-4'-carboxylate

G. Ganesh, P. S. Yuvaraj, C. Divakara, B. S. R. Reddy and A. SubbiahPandi

Abstract top

In the title compound, C22H21N3O4, the central pyrrolidine ring adopts a C-envelope conformation with a C atom 0.6593 (13) Å displaced from the mean plane formed by the remaining ring atoms. The indoline ring systems (r.m.s. devisations of 0.0356 and 0.0547 Å) are almost perpendicular to the mean plane of the pyrrolidine ring, making dihedral angles of 89.7 (6) and 82.5 (6)°. The acetate group attached to the pyrrolidine ring assumes an extended conformation. In the crystal,N-H...O and C-H...O hydrogen bonds connect adjacent molecules, forming an infinite tape extending along [1-1-1]. The crystal packing is further consolidated by strong [pi]-[pi] interactions with a centroid-centroid distance of 3.2585 (8) Å. The title compound is a polymorph of previously reported monoclinic structure [Ganesh et al. (2012). Acta Cryst. E68, o2902-o2903].

Comment top

We have recently reported the structure of the title compound in the monoclinic system (Ganesh et al., 2012). Here we report the structural details of its triclinic polymorph.

The bond lengths and angles in the title molecule (Fig. 1) are within normal ranges and comparable to those reported for its triclinic polymorph (Ganesh et al., 2012) and a closely related structure (Wei et al., 2011). The indoline ring systems (N1/C2-C9 and N3/C12/C16-C22) are individually planar (rmsd's 0.0356 and 0.0547 Å, respectively) and make dihedral angles of 89.69 (6) ° and 82.48 (6)° with respect to the mean plane of the pyrrolidine ring system (N2/C3/C10–C12). The pyrrolidine ring [N2/C3/C10-C12] adopts a C12-envelop conformation with C12 0.6593 (13) Å displaced from the mean-plane formed by the remaining ring atoms. The acetate group assumes an extended conformation (torsion angle C10–C14–O4–C15 = 176.3 (2) °).

The crystal structure is stabilized by intermolecular N3—H3···O1 and C15—H15B···O1 hydrogen bonds. There are strong ππ interactions with a centroid-centroid distance of 3.2585 (8) Å between Cg1 and Cg3 rings. {Cg1 and Cg3 are the centroids of the N1/C2-C5 and N3/C12/C16-C18 rings respectively}.

Related literature top

For background literature and the previously reported polymorph, see: Ganesh et al. (2008). For a related structure, see: Wei et al. (2011).

Experimental top

A mixture of 1 eq of (E)-methyl 2-(1-methyl-2-oxoindolin-3-ylidene) acetate, 1 eq of isatin and 1.5 eq of sarcosine dissolved in acetonitrile was refluxed at 353 K for 8 h. Upon completion of the reaction as determined with the aid of TLC, the reaction mixture was extracted with ethyl acetate and water. The product was dried and purified by column chromatography using ethyl acetate and hexane (1:9) as an elutent to afford the title compound in pure form. (Yield = 90%). Single crystals suitable for X-ray diffraction were obtained by slow evaporation of a solution of the title compound in ethyl acetate at room temperature.

Refinement top

All H atoms were fixed geometrically and allowed to ride on their parent C atoms, with N—H = 0.86 Å and C—H distances in the range 0.93–0.98 Å with Uiso(H) = 1.5Ueq(methyl C) and 1.2Ueq(non-methyl C/N).

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with the atom numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are presented as small spheres of arbitrary radius.
[Figure 2] Fig. 2. A view of the hydrogen bonds (dotted lines) in the crystal structure of the title compound. H atoms non-participating in hydrogen- bonding were omitted for clarity.
Methyl (3R,3'S)-1',1''-dimethyl-2,2''-dioxodispiro[indoline- 3,2'-pyrrolidine-3',3''-indoline]-4'-carboxylate top
Crystal data top
C22H21N3O4Z = 2
Mr = 391.42F(000) = 412
Triclinic, P1Dx = 1.319 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 9.4418 (3) ÅCell parameters from 8469 reflections
b = 10.0132 (3) Åθ = 2.4–34.7°
c = 12.8861 (4) ŵ = 0.09 mm1
α = 67.465 (2)°T = 293 K
β = 88.237 (2)°Block, colourless
γ = 62.842 (1)°0.25 × 0.22 × 0.19 mm
V = 985.68 (5) Å3
Data collection top
Bruker APEXII CCD area-detector
diffractometer
8469 independent reflections
Radiation source: fine-focus sealed tube5108 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.028
ω and φ scansθmax = 34.7°, θmin = 2.4°
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
h = 1515
Tmin = 0.978, Tmax = 0.983k = 1616
23829 measured reflectionsl = 2020
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)] = 0.051Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.158H-atom parameters constrained
S = 1.08 w = 1/[σ2(Fo2) + (0.0823P)2 + 0.0657P]
where P = (Fo2 + 2Fc2)/3
8469 reflections(Δ/σ)max < 0.001
265 parametersΔρmax = 0.29 e Å3
0 restraintsΔρmin = 0.27 e Å3
Crystal data top
C22H21N3O4γ = 62.842 (1)°
Mr = 391.42V = 985.68 (5) Å3
Triclinic, P1Z = 2
a = 9.4418 (3) ÅMo Kα radiation
b = 10.0132 (3) ŵ = 0.09 mm1
c = 12.8861 (4) ÅT = 293 K
α = 67.465 (2)°0.25 × 0.22 × 0.19 mm
β = 88.237 (2)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer
8469 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
5108 reflections with I > 2σ(I)
Tmin = 0.978, Tmax = 0.983Rint = 0.028
23829 measured reflectionsθmax = 34.7°
Refinement top
R[F2 > 2σ(F2)] = 0.051H-atom parameters constrained
wR(F2) = 0.158Δρmax = 0.29 e Å3
S = 1.08Δρmin = 0.27 e Å3
8469 reflectionsAbsolute structure: ?
265 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
C10.7776 (3)1.0526 (3)0.51871 (15)0.0796 (6)
H1A0.66721.10890.52720.119*
H1B0.83111.11340.52100.119*
H1C0.83140.94420.57970.119*
C20.77232 (13)0.91697 (13)0.39598 (9)0.0340 (2)
C30.76315 (11)0.95234 (11)0.26878 (8)0.02661 (19)
C40.76056 (12)1.11630 (12)0.21751 (10)0.0322 (2)
C50.77058 (15)1.16217 (15)0.30477 (11)0.0422 (3)
C60.7641 (2)1.3110 (2)0.28366 (17)0.0670 (5)
H60.77391.33930.34290.080*
C70.7427 (2)1.41584 (19)0.17152 (19)0.0769 (6)
H70.73741.51720.15480.092*
C80.7291 (2)1.37485 (16)0.08406 (16)0.0648 (4)
H80.71361.44900.00910.078*
C90.73808 (15)1.22285 (14)0.10554 (11)0.0443 (3)
H90.72921.19470.04610.053*
C100.61443 (11)0.95525 (12)0.21822 (9)0.0294 (2)
H100.59640.86890.27570.035*
C110.66671 (12)0.90746 (15)0.11868 (10)0.0370 (2)
H11A0.64830.81730.12450.044*
H11B0.60701.00060.04650.044*
C120.90212 (11)0.81284 (11)0.24386 (8)0.02558 (18)
C130.93053 (14)0.73661 (15)0.08136 (10)0.0399 (3)
H13A1.04050.71580.08530.060*
H13B0.88290.77890.00330.060*
H13C0.92820.63570.12500.060*
C140.46237 (12)1.11772 (13)0.18539 (10)0.0347 (2)
C150.2897 (3)1.3079 (2)0.25589 (17)0.0936 (7)
H15A0.31431.39460.21310.140*
H15B0.26441.31250.32760.140*
H15C0.19861.32140.21350.140*
C160.92790 (12)0.63976 (11)0.32962 (8)0.0289 (2)
C171.16767 (12)0.63888 (13)0.34810 (9)0.0326 (2)
C181.06891 (11)0.79224 (12)0.26043 (9)0.0299 (2)
C191.13393 (14)0.89045 (15)0.19952 (12)0.0440 (3)
H191.06930.99230.13970.053*
C201.29723 (16)0.83568 (18)0.22851 (14)0.0543 (3)
H201.34220.90140.18800.065*
C211.39322 (15)0.68469 (19)0.31685 (14)0.0547 (4)
H211.50240.64990.33530.066*
C221.32993 (14)0.58367 (17)0.37874 (12)0.0482 (3)
H221.39460.48220.43890.058*
N10.78263 (14)1.03949 (13)0.41018 (9)0.0459 (3)
N20.83966 (10)0.85688 (10)0.12758 (7)0.02941 (18)
N31.08062 (11)0.55400 (11)0.38933 (8)0.0349 (2)
H31.11910.45870.44580.042*
O10.77037 (12)0.79974 (10)0.47206 (7)0.0499 (2)
O20.83142 (10)0.58935 (10)0.33842 (7)0.0409 (2)
O30.38293 (12)1.20557 (12)0.09240 (8)0.0593 (3)
O40.42723 (12)1.15085 (11)0.27609 (8)0.0563 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.1180 (16)0.0905 (13)0.0559 (10)0.0537 (12)0.0155 (10)0.0508 (10)
C20.0382 (5)0.0283 (5)0.0297 (5)0.0120 (4)0.0025 (4)0.0110 (4)
C30.0304 (4)0.0215 (4)0.0268 (5)0.0134 (3)0.0023 (3)0.0077 (3)
C40.0331 (5)0.0223 (4)0.0400 (6)0.0148 (4)0.0053 (4)0.0098 (4)
C50.0475 (6)0.0353 (6)0.0548 (8)0.0246 (5)0.0098 (5)0.0234 (5)
C60.0847 (11)0.0541 (8)0.0965 (13)0.0476 (8)0.0291 (9)0.0476 (9)
C70.0947 (13)0.0401 (7)0.1167 (16)0.0464 (9)0.0458 (11)0.0374 (9)
C80.0760 (10)0.0301 (6)0.0769 (11)0.0284 (7)0.0299 (8)0.0089 (7)
C90.0500 (6)0.0282 (5)0.0453 (7)0.0189 (5)0.0117 (5)0.0064 (5)
C100.0274 (4)0.0264 (4)0.0334 (5)0.0130 (4)0.0027 (4)0.0112 (4)
C110.0291 (4)0.0416 (6)0.0421 (6)0.0132 (4)0.0001 (4)0.0234 (5)
C120.0269 (4)0.0216 (4)0.0264 (5)0.0127 (3)0.0022 (3)0.0067 (3)
C130.0400 (5)0.0421 (6)0.0370 (6)0.0152 (5)0.0088 (4)0.0216 (5)
C140.0307 (5)0.0321 (5)0.0385 (6)0.0134 (4)0.0060 (4)0.0142 (4)
C150.0981 (14)0.0496 (9)0.0712 (11)0.0100 (9)0.0338 (10)0.0235 (8)
C160.0345 (5)0.0230 (4)0.0280 (5)0.0140 (4)0.0065 (4)0.0093 (4)
C170.0308 (4)0.0308 (5)0.0313 (5)0.0122 (4)0.0003 (4)0.0110 (4)
C180.0280 (4)0.0275 (4)0.0323 (5)0.0141 (4)0.0019 (4)0.0093 (4)
C190.0375 (5)0.0375 (6)0.0529 (7)0.0237 (5)0.0029 (5)0.0075 (5)
C200.0395 (6)0.0593 (8)0.0714 (10)0.0340 (6)0.0086 (6)0.0215 (7)
C210.0313 (5)0.0623 (8)0.0714 (9)0.0229 (6)0.0003 (6)0.0275 (7)
C220.0324 (5)0.0454 (7)0.0511 (7)0.0102 (5)0.0081 (5)0.0143 (6)
N10.0614 (6)0.0455 (6)0.0404 (6)0.0272 (5)0.0053 (5)0.0250 (5)
N20.0285 (4)0.0307 (4)0.0262 (4)0.0124 (3)0.0022 (3)0.0112 (3)
N30.0359 (4)0.0236 (4)0.0309 (5)0.0102 (3)0.0015 (3)0.0025 (3)
O10.0732 (6)0.0317 (4)0.0308 (4)0.0189 (4)0.0122 (4)0.0076 (3)
O20.0455 (4)0.0325 (4)0.0490 (5)0.0256 (3)0.0095 (4)0.0125 (4)
O30.0468 (5)0.0492 (5)0.0499 (6)0.0017 (4)0.0116 (4)0.0191 (5)
O40.0584 (6)0.0415 (5)0.0428 (5)0.0039 (4)0.0154 (4)0.0178 (4)
Geometric parameters (Å, º) top
C1—N11.4514 (18)C12—N21.4484 (13)
C1—H1A0.9600C12—C181.5028 (13)
C1—H1B0.9600C12—C161.5645 (13)
C1—H1C0.9600C13—N21.4548 (14)
C2—O11.2149 (13)C13—H13A0.9600
C2—N11.3529 (15)C13—H13B0.9600
C2—C31.5348 (14)C13—H13C0.9600
C3—C41.5052 (13)C14—O31.1904 (14)
C3—C101.5497 (13)C14—O41.3263 (14)
C3—C121.5558 (13)C15—O41.4389 (17)
C4—C91.3775 (16)C15—H15A0.9600
C4—C51.3879 (17)C15—H15B0.9600
C5—C61.3808 (18)C15—H15C0.9600
C5—N11.4035 (17)C16—O21.2112 (12)
C6—C71.376 (3)C16—N31.3565 (13)
C6—H60.9300C17—C221.3803 (15)
C7—C81.366 (3)C17—C181.3899 (14)
C7—H70.9300C17—N31.3946 (14)
C8—C91.4003 (18)C18—C191.3748 (15)
C8—H80.9300C19—C201.3871 (16)
C9—H90.9300C19—H190.9300
C10—C141.5048 (14)C20—C211.377 (2)
C10—C111.5276 (15)C20—H200.9300
C10—H100.9800C21—C221.386 (2)
C11—N21.4656 (13)C21—H210.9300
C11—H11A0.9700C22—H220.9300
C11—H11B0.9700N3—H30.8600
N1—C1—H1A109.5C18—C12—C16101.43 (7)
N1—C1—H1B109.5C3—C12—C16110.59 (7)
H1A—C1—H1B109.5N2—C13—H13A109.5
N1—C1—H1C109.5N2—C13—H13B109.5
H1A—C1—H1C109.5H13A—C13—H13B109.5
H1B—C1—H1C109.5N2—C13—H13C109.5
O1—C2—N1125.04 (11)H13A—C13—H13C109.5
O1—C2—C3126.49 (10)H13B—C13—H13C109.5
N1—C2—C3108.47 (9)O3—C14—O4123.86 (10)
C4—C3—C2101.98 (8)O3—C14—C10126.06 (10)
C4—C3—C10113.45 (8)O4—C14—C10110.09 (9)
C2—C3—C10113.21 (8)O4—C15—H15A109.5
C4—C3—C12114.98 (8)O4—C15—H15B109.5
C2—C3—C12113.55 (8)H15A—C15—H15B109.5
C10—C3—C12100.24 (7)O4—C15—H15C109.5
C9—C4—C5120.03 (10)H15A—C15—H15C109.5
C9—C4—C3131.23 (10)H15B—C15—H15C109.5
C5—C4—C3108.51 (10)O2—C16—N3126.22 (9)
C6—C5—C4122.02 (14)O2—C16—C12126.37 (9)
C6—C5—N1128.08 (13)N3—C16—C12107.37 (8)
C4—C5—N1109.88 (10)C22—C17—C18121.67 (11)
C7—C6—C5117.35 (15)C22—C17—N3128.28 (10)
C7—C6—H6121.3C18—C17—N3109.88 (9)
C5—C6—H6121.3C19—C18—C17119.80 (10)
C8—C7—C6121.67 (13)C19—C18—C12130.94 (9)
C8—C7—H7119.2C17—C18—C12109.02 (8)
C6—C7—H7119.2C18—C19—C20119.12 (11)
C7—C8—C9120.99 (15)C18—C19—H19120.4
C7—C8—H8119.5C20—C19—H19120.4
C9—C8—H8119.5C21—C20—C19120.50 (12)
C4—C9—C8117.92 (14)C21—C20—H20119.8
C4—C9—H9121.0C19—C20—H20119.8
C8—C9—H9121.0C20—C21—C22121.16 (11)
C14—C10—C11114.04 (9)C20—C21—H21119.4
C14—C10—C3113.06 (8)C22—C21—H21119.4
C11—C10—C3104.49 (8)C17—C22—C21117.72 (12)
C14—C10—H10108.3C17—C22—H22121.1
C11—C10—H10108.3C21—C22—H22121.1
C3—C10—H10108.3C2—N1—C5111.02 (10)
N2—C11—C10105.43 (8)C2—N1—C1122.76 (12)
N2—C11—H11A110.7C5—N1—C1125.37 (12)
C10—C11—H11A110.7C12—N2—C13115.72 (8)
N2—C11—H11B110.7C12—N2—C11108.13 (8)
C10—C11—H11B110.7C13—N2—C11114.45 (8)
H11A—C11—H11B108.8C16—N3—C17111.89 (8)
N2—C12—C18114.11 (8)C16—N3—H3124.1
N2—C12—C3100.86 (7)C17—N3—H3124.1
C18—C12—C3117.03 (8)C14—O4—C15116.15 (12)
N2—C12—C16113.33 (8)
O1—C2—C3—C4176.72 (11)C18—C12—C16—O2171.33 (10)
N1—C2—C3—C43.10 (11)C3—C12—C16—O263.84 (13)
O1—C2—C3—C1054.46 (14)N2—C12—C16—N3129.09 (9)
N1—C2—C3—C10125.36 (10)C18—C12—C16—N36.33 (10)
O1—C2—C3—C1258.99 (14)C3—C12—C16—N3118.50 (9)
N1—C2—C3—C12121.20 (10)C22—C17—C18—C192.17 (18)
C2—C3—C4—C9173.11 (11)N3—C17—C18—C19173.57 (10)
C10—C3—C4—C951.01 (15)C22—C17—C18—C12177.20 (10)
C12—C3—C4—C963.56 (15)N3—C17—C18—C121.46 (12)
C2—C3—C4—C51.16 (11)N2—C12—C18—C1947.46 (15)
C10—C3—C4—C5123.25 (10)C3—C12—C18—C1969.93 (15)
C12—C3—C4—C5122.17 (10)C16—C12—C18—C19169.68 (12)
C9—C4—C5—C62.22 (19)N2—C12—C18—C17126.83 (9)
C3—C4—C5—C6177.24 (12)C3—C12—C18—C17115.78 (10)
C9—C4—C5—N1176.11 (10)C16—C12—C18—C174.61 (11)
C3—C4—C5—N11.09 (13)C17—C18—C19—C201.35 (19)
C4—C5—C6—C71.7 (2)C12—C18—C19—C20175.14 (12)
N1—C5—C6—C7176.26 (14)C18—C19—C20—C210.2 (2)
C5—C6—C7—C80.3 (3)C19—C20—C21—C220.1 (2)
C6—C7—C8—C90.6 (3)C18—C17—C22—C211.76 (19)
C5—C4—C9—C81.18 (18)N3—C17—C22—C21173.13 (12)
C3—C4—C9—C8174.90 (12)C20—C21—C22—C170.6 (2)
C7—C8—C9—C40.2 (2)O1—C2—N1—C5175.84 (11)
C4—C3—C10—C1433.41 (12)C3—C2—N1—C53.98 (13)
C2—C3—C10—C1482.20 (10)O1—C2—N1—C15.9 (2)
C12—C3—C10—C14156.52 (8)C3—C2—N1—C1173.94 (13)
C4—C3—C10—C1191.15 (10)C6—C5—N1—C2174.92 (14)
C2—C3—C10—C11153.24 (8)C4—C5—N1—C23.28 (15)
C12—C3—C10—C1131.96 (9)C6—C5—N1—C15.3 (2)
C14—C10—C11—N2132.27 (9)C4—C5—N1—C1172.92 (14)
C3—C10—C11—N28.34 (11)C18—C12—N2—C1362.19 (11)
C4—C3—C12—N277.70 (9)C3—C12—N2—C13171.46 (8)
C2—C3—C12—N2165.37 (8)C16—C12—N2—C1353.25 (11)
C10—C3—C12—N244.33 (8)C18—C12—N2—C11167.94 (8)
C4—C3—C12—C1846.69 (12)C3—C12—N2—C1141.58 (9)
C2—C3—C12—C1870.23 (11)C16—C12—N2—C1176.63 (10)
C10—C3—C12—C18168.72 (8)C10—C11—N2—C1221.22 (11)
C4—C3—C12—C16162.12 (8)C10—C11—N2—C13151.79 (9)
C2—C3—C12—C1645.19 (10)O2—C16—N3—C17171.68 (10)
C10—C3—C12—C1675.85 (9)C12—C16—N3—C175.99 (11)
C11—C10—C14—O31.20 (16)C22—C17—N3—C16172.33 (12)
C3—C10—C14—O3120.39 (13)C18—C17—N3—C163.04 (12)
C11—C10—C14—O4178.99 (9)O3—C14—O4—C153.9 (2)
C3—C10—C14—O459.81 (12)C10—C14—O4—C15176.33 (15)
N2—C12—C16—O248.57 (13)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3···O1i0.862.102.9107 (12)157
C15—H15B···O1ii0.962.473.363 (2)155
Symmetry codes: (i) x+2, y+1, z+1; (ii) x+1, y+2, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3···O1i0.862.102.9107 (12)156.9
C15—H15B···O1ii0.962.473.363 (2)154.9
Symmetry codes: (i) x+2, y+1, z+1; (ii) x+1, y+2, z+1.
Acknowledgements top

The authors thank Dr Babu Varghese, SAIF, IIT, Chennai, India, for the data collection. ASP thanks the University Grants Commission, India, for a Minor research Project.

references
References top

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