An unexpected N-substituted oxindole: 1-(3,3,5-trimethyl-2-phenyl-1,2-oxazolidin-5-yl)-1H-indol-3(2H)-one

The mol­ecule of the title compound, C₂₀H₂₂N₂O₂, an N-substituted oxindole obtained unexpectedly, is composed of a heterocyclic ring, which adopts an N-envelope conformation, and an isoindole group which is essentially planar.

Key indicators

• Single-crystal X-ray study
• T = 173 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.042
• wR factor = 0.108
• Data-to-parameter ratio = 17.4

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   1 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: COLLECT (Hooft, 1998); cell refinement: DENZO (Otwinowski & Minor, 1997); data reduction: SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SAPI91 (Fan, 1991); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).

1-(3,3,5-trimethyl-2-phenyl-1,2-oxazolidin-5-yl)-1H-indol-3(2H)-one

Crystal data

C20H22N2O2	F(000) = 688
Mr = 322.40	Dx = 1.277 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 6053 reflections
a = 10.321 (3) Å	θ = 3.5–27.5°
b = 14.446 (4) Å	µ = 0.08 mm^−1
c = 11.378 (4) Å	T = 173 K
β = 98.554 (12)°	Prism, colorless
V = 1677.6 (9) Å^3	0.28 × 0.20 × 0.16 mm
Z = 4

Data collection

Nonius KappaCCD diffractometer	3825 independent reflections
Radiation source: fine-focus sealed tube	2632 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.025
ω and φ scans	θmax = 27.5°, θmin = 3.5°
Absorption correction: multi-scan (SORTAV; Blessing, 1997)	h = −11→13
Tmin = 0.977, Tmax = 0.987	k = −17→18
6053 measured reflections	l = −14→14

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.108	H-atom parameters constrained
S = 1.02	w = 1/[σ^2(Fo^2) + (0.052P)^2 + 0.104P] where P = (Fo^2 + 2Fc^2)/3
3825 reflections	(Δ/σ)max = 0.001
220 parameters	Δρmax = 0.20 e Å^−3
0 restraints	Δρmin = −0.21 e Å^−3

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1	0.32076 (8)	0.06343 (6)	−0.02365 (7)	0.0251 (2)
O2	0.11403 (9)	0.04877 (7)	−0.37098 (8)	0.0343 (3)
N1	0.20768 (9)	0.06345 (7)	0.04153 (9)	0.0226 (3)
N2	0.22364 (10)	−0.01500 (8)	−0.19824 (9)	0.0244 (3)
C1	0.26463 (12)	0.07637 (9)	−0.14353 (11)	0.0241 (3)
C2	0.14409 (12)	0.13848 (10)	−0.13813 (12)	0.0273 (3)
H2A	0.1544	0.1989	−0.1767	0.033*
H2B	0.0633	0.1083	−0.1782	0.033*
C3	0.13877 (12)	0.15100 (9)	−0.00516 (11)	0.0245 (3)
C4	0.37133 (12)	0.11751 (10)	−0.20610 (12)	0.0299 (3)
H4A	0.3398	0.1219	−0.2915	0.036*
H4B	0.4491	0.0778	−0.1929	0.036*
H4C	0.3939	0.1794	−0.1743	0.036*
C5	−0.00048 (12)	0.15053 (10)	0.02358 (13)	0.0323 (3)
H5A	−0.0502	0.2014	−0.0187	0.039*
H5B	0.0015	0.1585	0.1094	0.039*
H5C	−0.0425	0.0915	−0.0014	0.039*
C6	0.21117 (13)	0.23798 (10)	0.04388 (13)	0.0322 (3)
H6A	0.1666	0.2927	0.0064	0.039*
H6B	0.3014	0.2361	0.0267	0.039*
H6C	0.2120	0.2410	0.1300	0.039*
C7	0.25868 (12)	0.06192 (9)	0.16572 (11)	0.0238 (3)
C8	0.17162 (13)	0.03570 (10)	0.24268 (12)	0.0300 (3)
H8	0.0845	0.0182	0.2114	0.036*
C9	0.21170 (15)	0.03505 (10)	0.36421 (13)	0.0351 (4)
H9	0.1512	0.0195	0.4163	0.042*
C10	0.33994 (15)	0.05701 (11)	0.41012 (13)	0.0369 (4)
H10	0.3678	0.0561	0.4935	0.044*
C11	0.42687 (14)	0.08027 (10)	0.33391 (13)	0.0350 (4)
H11	0.5152	0.0941	0.3653	0.042*
C12	0.38697 (13)	0.08371 (10)	0.21185 (12)	0.0298 (3)
H12	0.4473	0.1009	0.1603	0.036*
C13	0.15714 (12)	−0.01865 (10)	−0.31306 (12)	0.0276 (3)
C14	0.14893 (14)	−0.11871 (10)	−0.35257 (13)	0.0345 (3)
H14A	0.0570	−0.1405	−0.3662	0.041*
H14B	0.1877	−0.1273	−0.4264	0.041*
C15	0.22670 (13)	−0.16867 (10)	−0.25062 (12)	0.0302 (3)
C16	0.25781 (14)	−0.26120 (11)	−0.23552 (14)	0.0397 (4)
H16	0.2292	−0.3046	−0.2967	0.048*
C17	0.33152 (15)	−0.29019 (11)	−0.12971 (15)	0.0434 (4)
H17	0.3546	−0.3536	−0.1187	0.052*
C18	0.37126 (14)	−0.22708 (11)	−0.04071 (14)	0.0372 (4)
H18	0.4208	−0.2481	0.0314	0.045*
C19	0.34072 (12)	−0.13343 (10)	−0.05376 (13)	0.0302 (3)
H19	0.3680	−0.0906	0.0083	0.036*
C20	0.26919 (11)	−0.10490 (9)	−0.16041 (11)	0.0247 (3)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0248 (4)	0.0323 (6)	0.0191 (5)	0.0012 (4)	0.0059 (4)	−0.0016 (4)
O2	0.0445 (6)	0.0341 (6)	0.0233 (5)	0.0010 (5)	0.0021 (4)	0.0012 (5)
N1	0.0248 (5)	0.0238 (6)	0.0204 (6)	0.0008 (4)	0.0070 (4)	−0.0003 (5)
N2	0.0294 (5)	0.0240 (6)	0.0198 (6)	0.0002 (5)	0.0033 (4)	−0.0009 (5)
C1	0.0275 (6)	0.0259 (8)	0.0188 (7)	−0.0004 (5)	0.0031 (5)	−0.0005 (5)
C2	0.0301 (7)	0.0275 (8)	0.0242 (7)	0.0020 (6)	0.0039 (5)	0.0000 (6)
C3	0.0289 (6)	0.0211 (7)	0.0240 (7)	0.0003 (5)	0.0051 (5)	−0.0002 (6)
C4	0.0318 (7)	0.0318 (8)	0.0267 (7)	−0.0029 (6)	0.0066 (5)	0.0006 (6)
C5	0.0303 (7)	0.0338 (8)	0.0338 (8)	0.0041 (6)	0.0083 (6)	0.0018 (7)
C6	0.0398 (7)	0.0240 (8)	0.0327 (8)	−0.0012 (6)	0.0052 (6)	−0.0012 (6)
C7	0.0305 (7)	0.0193 (7)	0.0218 (7)	0.0012 (5)	0.0042 (5)	−0.0020 (5)
C8	0.0332 (7)	0.0308 (8)	0.0271 (8)	−0.0001 (6)	0.0079 (6)	0.0017 (6)
C9	0.0469 (8)	0.0328 (9)	0.0283 (8)	0.0069 (7)	0.0141 (6)	0.0045 (7)
C10	0.0537 (9)	0.0356 (9)	0.0208 (7)	0.0125 (7)	0.0033 (6)	0.0000 (6)
C11	0.0367 (7)	0.0364 (9)	0.0295 (8)	0.0029 (6)	−0.0028 (6)	−0.0044 (7)
C12	0.0320 (7)	0.0318 (8)	0.0258 (7)	−0.0004 (6)	0.0053 (5)	−0.0016 (6)
C13	0.0309 (7)	0.0314 (8)	0.0211 (7)	−0.0011 (6)	0.0060 (5)	−0.0021 (6)
C14	0.0426 (8)	0.0317 (9)	0.0290 (8)	−0.0024 (7)	0.0042 (6)	−0.0078 (7)
C15	0.0328 (7)	0.0280 (8)	0.0310 (8)	−0.0028 (6)	0.0086 (6)	−0.0035 (6)
C16	0.0449 (8)	0.0285 (8)	0.0457 (10)	−0.0030 (7)	0.0069 (7)	−0.0067 (7)
C17	0.0457 (9)	0.0280 (9)	0.0565 (11)	0.0007 (7)	0.0078 (8)	0.0046 (8)
C18	0.0360 (7)	0.0324 (9)	0.0422 (9)	0.0005 (6)	0.0025 (6)	0.0088 (7)
C19	0.0295 (7)	0.0308 (8)	0.0306 (8)	−0.0023 (6)	0.0053 (6)	0.0019 (6)
C20	0.0241 (6)	0.0230 (7)	0.0284 (7)	−0.0012 (5)	0.0086 (5)	0.0019 (6)

Geometric parameters (Å, º)

O1—C1	1.4128 (15)	C7—C8	1.3970 (18)
O1—N1	1.4730 (13)	C8—C9	1.383 (2)
O2—C13	1.2221 (17)	C8—H8	0.9500
N1—C7	1.4328 (17)	C9—C10	1.386 (2)
N1—C3	1.5083 (17)	C9—H9	0.9500
N2—C13	1.3834 (17)	C10—C11	1.379 (2)
N2—C20	1.4257 (17)	C10—H10	0.9500
N2—C1	1.4934 (18)	C11—C12	1.390 (2)
C1—C4	1.5186 (17)	C11—H11	0.9500
C1—C2	1.5426 (18)	C12—H12	0.9500
C2—C3	1.5328 (19)	C13—C14	1.512 (2)
C2—H2A	0.9900	C14—C15	1.495 (2)
C2—H2B	0.9900	C14—H14A	0.9900
C3—C5	1.5206 (18)	C14—H14B	0.9900
C3—C6	1.5247 (19)	C15—C16	1.379 (2)
C4—H4A	0.9800	C15—C20	1.4003 (19)
C4—H4B	0.9800	C16—C17	1.390 (2)
C4—H4C	0.9800	C16—H16	0.9500
C5—H5A	0.9800	C17—C18	1.379 (2)
C5—H5B	0.9800	C17—H17	0.9500
C5—H5C	0.9800	C18—C19	1.392 (2)
C6—H6A	0.9800	C18—H18	0.9500
C6—H6B	0.9800	C19—C20	1.3860 (19)
C6—H6C	0.9800	C19—H19	0.9500
C7—C12	1.3860 (19)
C1—O1—N1	104.14 (8)	C12—C7—N1	124.06 (11)
C7—N1—O1	107.11 (9)	C8—C7—N1	116.50 (11)
C7—N1—C3	116.43 (10)	C9—C8—C7	120.26 (13)
O1—N1—C3	100.97 (9)	C9—C8—H8	119.9
C13—N2—C20	110.21 (11)	C7—C8—H8	119.9
C13—N2—C1	119.82 (11)	C8—C9—C10	120.15 (13)
C20—N2—C1	128.24 (10)	C8—C9—H9	119.9
O1—C1—N2	109.60 (10)	C10—C9—H9	119.9
O1—C1—C4	106.42 (10)	C11—C10—C9	119.54 (14)
N2—C1—C4	109.32 (10)	C11—C10—H10	120.2
O1—C1—C2	104.82 (10)	C9—C10—H10	120.2
N2—C1—C2	110.52 (10)	C10—C11—C12	120.89 (14)
C4—C1—C2	115.87 (11)	C10—C11—H11	119.6
C3—C2—C1	104.80 (10)	C12—C11—H11	119.6
C3—C2—H2A	110.8	C7—C12—C11	119.65 (12)
C1—C2—H2A	110.8	C7—C12—H12	120.2
C3—C2—H2B	110.8	C11—C12—H12	120.2
C1—C2—H2B	110.8	O2—C13—N2	124.65 (13)
H2A—C2—H2B	108.9	O2—C13—C14	126.98 (13)
N1—C3—C5	109.37 (10)	N2—C13—C14	108.37 (12)
N1—C3—C6	112.48 (11)	C15—C14—C13	103.35 (11)
C5—C3—C6	110.64 (11)	C15—C14—H14A	111.1
N1—C3—C2	99.47 (10)	C13—C14—H14A	111.1
C5—C3—C2	112.67 (11)	C15—C14—H14B	111.1
C6—C3—C2	111.77 (11)	C13—C14—H14B	111.1
C1—C4—H4A	109.5	H14A—C14—H14B	109.1
C1—C4—H4B	109.5	C16—C15—C20	120.30 (14)
H4A—C4—H4B	109.5	C16—C15—C14	130.75 (14)
C1—C4—H4C	109.5	C20—C15—C14	108.95 (13)
H4A—C4—H4C	109.5	C15—C16—C17	119.15 (15)
H4B—C4—H4C	109.5	C15—C16—H16	120.4
C3—C5—H5A	109.5	C17—C16—H16	120.4
C3—C5—H5B	109.5	C18—C17—C16	120.12 (15)
H5A—C5—H5B	109.5	C18—C17—H17	119.9
C3—C5—H5C	109.5	C16—C17—H17	119.9
H5A—C5—H5C	109.5	C17—C18—C19	121.76 (15)
H5B—C5—H5C	109.5	C17—C18—H18	119.1
C3—C6—H6A	109.5	C19—C18—H18	119.1
C3—C6—H6B	109.5	C20—C19—C18	117.71 (14)
H6A—C6—H6B	109.5	C20—C19—H19	121.1
C3—C6—H6C	109.5	C18—C19—H19	121.1
H6A—C6—H6C	109.5	C19—C20—C15	120.94 (13)
H6B—C6—H6C	109.5	C19—C20—N2	130.09 (12)
C12—C7—C8	119.44 (13)	C15—C20—N2	108.95 (12)
C1—O1—N1—C7	−173.08 (10)	C7—C8—C9—C10	−2.5 (2)
C1—O1—N1—C3	−50.81 (11)	C8—C9—C10—C11	0.6 (2)
N1—O1—C1—N2	−85.70 (10)	C9—C10—C11—C12	1.3 (2)
N1—O1—C1—C4	156.20 (10)	C8—C7—C12—C11	−0.8 (2)
N1—O1—C1—C2	32.93 (12)	N1—C7—C12—C11	179.90 (13)
C13—N2—C1—O1	175.20 (9)	C10—C11—C12—C7	−1.1 (2)
C20—N2—C1—O1	−21.35 (15)	C20—N2—C13—O2	−175.45 (12)
C13—N2—C1—C4	−68.51 (14)	C1—N2—C13—O2	−9.25 (18)
C20—N2—C1—C4	94.93 (14)	C20—N2—C13—C14	4.16 (13)
C13—N2—C1—C2	60.16 (14)	C1—N2—C13—C14	170.37 (10)
C20—N2—C1—C2	−136.39 (12)	O2—C13—C14—C15	175.51 (12)
O1—C1—C2—C3	−3.43 (13)	N2—C13—C14—C15	−4.10 (14)
N2—C1—C2—C3	114.58 (11)	C13—C14—C15—C16	−177.97 (14)
C4—C1—C2—C3	−120.39 (12)	C13—C14—C15—C20	2.61 (14)
C7—N1—C3—C5	−80.50 (13)	C20—C15—C16—C17	0.1 (2)
O1—N1—C3—C5	163.97 (10)	C14—C15—C16—C17	−179.23 (14)
C7—N1—C3—C6	42.86 (14)	C15—C16—C17—C18	0.8 (2)
O1—N1—C3—C6	−72.67 (12)	C16—C17—C18—C19	−0.7 (2)
C7—N1—C3—C2	161.28 (10)	C17—C18—C19—C20	−0.5 (2)
O1—N1—C3—C2	45.75 (10)	C18—C19—C20—C15	1.46 (18)
C1—C2—C3—N1	−26.08 (12)	C18—C19—C20—N2	179.55 (12)
C1—C2—C3—C5	−141.81 (12)	C16—C15—C20—C19	−1.31 (19)
C1—C2—C3—C6	92.87 (13)	C14—C15—C20—C19	178.18 (11)
O1—N1—C7—C12	16.82 (16)	C16—C15—C20—N2	−179.76 (11)
C3—N1—C7—C12	−95.22 (15)	C14—C15—C20—N2	−0.27 (14)
O1—N1—C7—C8	−162.54 (11)	C13—N2—C20—C19	179.24 (12)
C3—N1—C7—C8	85.42 (14)	C1—N2—C20—C19	14.5 (2)
C12—C7—C8—C9	2.6 (2)	C13—N2—C20—C15	−2.49 (13)
N1—C7—C8—C9	−178.05 (12)	C1—N2—C20—C15	−167.22 (11)