Ethyl 2-amino-7,7-dimethyl-2',5-dioxo-spiro-[5,6,7,8-tetra-hydro-4H-chromene-4,3'(2'H)-1H-indole]-3-carboxyl-ate.

In the mol-ecule of the title compound, C(21)H(22)N(2)O(5), the indole system and the spiro-pyran ring are almost planar [maximum deviations of 0.0447 (17) and 0.0781 (17) Å, respectively]; the dihedral angle between them is 84.6 (3)°. The remaining six-membered ring adopts a twisted conformation. Intra-molecular N-H⋯O hydrogen bonds occur. In the crystal structure, intera-molecular N-H⋯O and C-H⋯O hydrogen bonds link the mol-ecules.

Related literature

For the indole nucleus, see: da Silva et al., (2001 ▶). For the anti­bacterial and fungicidal activities of n class="Chemical">indoles, see: Joshi & Chand (1982 ▶). Spiro­oxindole ring systems are found in a number of alkaloids, see: Abdel-Rahman et al. (2004 ▶). For our work on the preparation of heterocyclic compounds involving indole derivatives, see: Zhu et al. (2007 ▶). For puckering parameters, see: Cremer & Pople (1975 ▶).

Experimental

Crystal data

C21H22N2O5

M = 382.41

Monoclinic,

a = 8.4298 (14) Å

b = 11.6791 (17) Å

c = 19.024 (3) Å

β = 99.136 (4)°

V = 1849.2 (5) Å3

Z = 4

Mo Kα radiation

μ = 0.10 mm−1

T = 153 K

0.50 × 0.35 × 0.12 mm

Data collection

Rigaku Mercury diffractometer

Absorption correction: multi-scan (Jacobson, 1998 ▶) T min = 0.814, T max = 0.988

17728 measured reflections

3374 independent reflections

2944 reflections with I > 2σ(I)

R int = 0.041

Refinement

R[F 2 > 2σ(F 2)] = 0.049

wR(F 2) = 0.107

S = 1.15

3374 reflections

257 parameters

H-atom parameters constrained

Δρmax = 0.20 e Å−3

Δρmin = −0.23 e Å−3

Data collection: CrystalClear (Rigaku/MSC, 2001 ▶); cell refinement: CrystalClear; data reduction: CrystalStructure (Rigaku/MSC, 2004 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEPII (Johnson, 1976 ▶) and PLATON (Spek, 2009 ▶); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009 ▶).

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809055809/ds2016sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809055809/ds2016Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

C21H22N2O5	F(000) = 808
Mr = 382.41	Dx = 1.374 Mg m−3
Monoclinic, P21/n	Melting point = 518–519 K
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71070 Å
a = 8.4298 (14) Å	Cell parameters from 6298 reflections
b = 11.6791 (17) Å	θ = 3.0–25.3°
c = 19.024 (3) Å	µ = 0.10 mm−1
β = 99.136 (4)°	T = 153 K
V = 1849.2 (5) Å3	Block, colorless
Z = 4	0.50 × 0.35 × 0.12 mm

Rigaku Mercury diffractometer	3374 independent reflections
Radiation source: fine-focus sealed tube	2944 reflections with I > 2σ(I)
graphite	Rint = 0.041
Detector resolution: 7.31 pixels mm-1	θmax = 25.4°, θmin = 3.0°
ω scans	h = −10→10
Absorption correction: multi-scan (Jacobson, 1998)	k = −14→13
Tmin = 0.814, Tmax = 0.988	l = −22→22
17728 measured reflections

Refinement on F2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.049	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.107	H-atom parameters constrained
S = 1.15	w = 1/[σ2(Fo2) + (0.040P)2 + 0.757P] where P = (Fo2 + 2Fc2)/3
3374 reflections	(Δ/σ)max < 0.001
257 parameters	Δρmax = 0.20 e Å−3
0 restraints	Δρmin = −0.23 e Å−3

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.

	x	y	z	Uiso*/Ueq
O1	0.58254 (15)	0.33374 (11)	0.25244 (6)	0.0258 (3)
O2	0.34545 (16)	0.04523 (12)	0.09660 (7)	0.0315 (3)
O3	0.76243 (15)	0.05137 (11)	0.13053 (7)	0.0271 (3)
O4	0.93311 (15)	0.42547 (11)	0.12924 (7)	0.0276 (3)
O5	0.84779 (15)	0.28028 (12)	0.05510 (7)	0.0290 (3)
N1	0.7795 (2)	0.45339 (14)	0.23971 (9)	0.0323 (4)
H1A	0.8561	0.4825	0.2187	0.039*
H1B	0.7603	0.4822	0.2803	0.039*
N2	0.62096 (18)	0.09772 (13)	0.02113 (8)	0.0220 (3)
H2	0.6506	0.0396	−0.0032	0.026*
C1	0.4876 (2)	0.24020 (15)	0.23304 (9)	0.0213 (4)
C2	0.4815 (2)	0.18729 (15)	0.17020 (9)	0.0200 (4)
C3	0.5860 (2)	0.22220 (15)	0.11542 (9)	0.0200 (4)
C4	0.7072 (2)	0.31183 (15)	0.14793 (9)	0.0209 (4)
C5	0.6927 (2)	0.36589 (16)	0.21015 (9)	0.0229 (4)
C6	0.3686 (2)	0.09070 (16)	0.15531 (10)	0.0226 (4)
C7	0.2872 (2)	0.04575 (16)	0.21471 (10)	0.0255 (4)
H7A	0.3577	−0.0125	0.2415	0.031*
H7B	0.1864	0.0070	0.1936	0.031*
C8	0.2471 (2)	0.13669 (16)	0.26702 (9)	0.0231 (4)
C9	0.3984 (2)	0.20711 (17)	0.29162 (10)	0.0256 (4)
H9A	0.3679	0.2775	0.3152	0.031*
H9B	0.4710	0.1624	0.3275	0.031*
C10	0.1122 (2)	0.21397 (18)	0.23047 (11)	0.0316 (5)
H10A	0.1494	0.2558	0.1915	0.047*
H10B	0.0818	0.2686	0.2651	0.047*
H10C	0.0189	0.1670	0.2114	0.047*
C11	0.1937 (2)	0.07742 (18)	0.33125 (10)	0.0309 (5)
H11A	0.0951	0.0339	0.3155	0.046*
H11B	0.1734	0.1352	0.3661	0.046*
H11C	0.2784	0.0253	0.3532	0.046*
C12	0.6698 (2)	0.11300 (15)	0.09176 (9)	0.0213 (4)
C13	0.5176 (2)	0.18514 (15)	−0.00876 (9)	0.0215 (4)
C14	0.4506 (2)	0.20069 (17)	−0.07895 (10)	0.0279 (5)
H14	0.4678	0.1471	−0.1145	0.033*
C15	0.3570 (2)	0.29760 (18)	−0.09573 (11)	0.0324 (5)
H15	0.3084	0.3103	−0.1437	0.039*
C16	0.3332 (2)	0.37610 (18)	−0.04389 (11)	0.0319 (5)
H16	0.2705	0.4427	−0.0567	0.038*
C17	0.4006 (2)	0.35815 (16)	0.02711 (10)	0.0261 (4)
H17	0.3839	0.4116	0.0629	0.031*
C18	0.4919 (2)	0.26158 (15)	0.04424 (9)	0.0206 (4)
C19	0.8378 (2)	0.34677 (16)	0.11166 (9)	0.0226 (4)
C20	0.9853 (2)	0.29242 (19)	0.01860 (11)	0.0353 (5)
H20A	1.0827	0.3117	0.0529	0.042*
H20B	0.9661	0.3540	−0.0175	0.042*
C21	1.0062 (3)	0.1792 (2)	−0.01643 (12)	0.0434 (6)
H21A	1.0244	0.1191	0.0199	0.065*
H21B	1.0986	0.1833	−0.0417	0.065*
H21C	0.9091	0.1615	−0.0503	0.065*

	U11	U22	U33	U12	U13	U23
O1	0.0258 (7)	0.0279 (7)	0.0249 (7)	−0.0071 (6)	0.0076 (5)	−0.0071 (6)
O2	0.0358 (8)	0.0318 (8)	0.0291 (8)	−0.0101 (6)	0.0120 (6)	−0.0115 (6)
O3	0.0269 (7)	0.0275 (7)	0.0271 (7)	0.0066 (6)	0.0047 (6)	0.0049 (6)
O4	0.0237 (7)	0.0265 (7)	0.0321 (7)	−0.0066 (6)	0.0031 (6)	0.0005 (6)
O5	0.0266 (7)	0.0351 (8)	0.0275 (7)	−0.0099 (6)	0.0117 (6)	−0.0045 (6)
N1	0.0331 (10)	0.0342 (10)	0.0308 (9)	−0.0124 (8)	0.0087 (7)	−0.0130 (8)
N2	0.0249 (8)	0.0209 (8)	0.0213 (8)	−0.0001 (7)	0.0074 (6)	−0.0028 (6)
C1	0.0190 (9)	0.0216 (10)	0.0230 (9)	−0.0001 (7)	0.0024 (7)	−0.0002 (8)
C2	0.0192 (9)	0.0202 (10)	0.0212 (9)	0.0000 (7)	0.0049 (7)	0.0006 (7)
C3	0.0193 (9)	0.0198 (9)	0.0211 (9)	−0.0006 (7)	0.0040 (7)	−0.0015 (7)
C4	0.0197 (9)	0.0204 (10)	0.0223 (9)	−0.0003 (7)	0.0020 (7)	0.0006 (7)
C5	0.0202 (9)	0.0247 (10)	0.0235 (10)	−0.0015 (8)	0.0024 (8)	−0.0001 (8)
C6	0.0214 (9)	0.0205 (10)	0.0266 (10)	0.0026 (8)	0.0061 (8)	−0.0024 (8)
C7	0.0255 (10)	0.0232 (10)	0.0291 (10)	−0.0012 (8)	0.0082 (8)	0.0007 (8)
C8	0.0212 (9)	0.0241 (10)	0.0253 (10)	0.0019 (8)	0.0072 (8)	0.0026 (8)
C9	0.0261 (10)	0.0285 (11)	0.0229 (10)	0.0035 (8)	0.0066 (8)	0.0001 (8)
C10	0.0237 (10)	0.0332 (12)	0.0383 (12)	0.0061 (9)	0.0062 (9)	0.0047 (9)
C11	0.0317 (11)	0.0330 (12)	0.0308 (11)	0.0012 (9)	0.0134 (9)	0.0045 (9)
C12	0.0207 (9)	0.0203 (10)	0.0242 (10)	−0.0039 (8)	0.0073 (8)	0.0009 (8)
C13	0.0189 (9)	0.0239 (10)	0.0220 (9)	−0.0050 (8)	0.0047 (7)	0.0005 (8)
C14	0.0280 (10)	0.0342 (11)	0.0218 (10)	−0.0088 (9)	0.0051 (8)	0.0005 (8)
C15	0.0267 (11)	0.0413 (13)	0.0270 (11)	−0.0059 (9)	−0.0021 (8)	0.0092 (9)
C16	0.0238 (10)	0.0308 (11)	0.0391 (12)	0.0014 (9)	−0.0005 (9)	0.0122 (9)
C17	0.0212 (10)	0.0239 (10)	0.0333 (11)	−0.0017 (8)	0.0045 (8)	0.0001 (8)
C18	0.0175 (9)	0.0209 (10)	0.0235 (9)	−0.0042 (7)	0.0039 (7)	0.0006 (7)
C19	0.0212 (9)	0.0235 (10)	0.0219 (9)	−0.0001 (8)	−0.0003 (7)	0.0032 (8)
C20	0.0305 (11)	0.0459 (13)	0.0333 (11)	−0.0100 (10)	0.0167 (9)	−0.0016 (10)
C21	0.0393 (13)	0.0514 (15)	0.0449 (13)	−0.0047 (11)	0.0229 (11)	−0.0058 (11)

O1—C1	1.370 (2)	C8—C10	1.530 (3)
O1—C5	1.374 (2)	C8—C11	1.533 (3)
O2—C6	1.224 (2)	C9—H9A	0.9900
O3—C12	1.220 (2)	C9—H9B	0.9900
O4—C19	1.232 (2)	C10—H10A	0.9800
O5—C19	1.340 (2)	C10—H10B	0.9800
O5—C20	1.450 (2)	C10—H10C	0.9800
N1—C5	1.328 (2)	C11—H11A	0.9800
N1—H1A	0.8800	C11—H11B	0.9800
N1—H1B	0.8800	C11—H11C	0.9800
N2—C12	1.353 (2)	C13—C14	1.377 (3)
N2—C13	1.403 (2)	C13—C18	1.389 (3)
N2—H2	0.8800	C14—C15	1.387 (3)
C1—C2	1.339 (2)	C14—H14	0.9500
C1—C9	1.491 (3)	C15—C16	1.384 (3)
C2—C6	1.474 (3)	C15—H15	0.9500
C2—C3	1.523 (2)	C16—C17	1.396 (3)
C3—C4	1.524 (2)	C16—H16	0.9500
C3—C18	1.528 (2)	C17—C18	1.375 (3)
C3—C12	1.559 (3)	C17—H17	0.9500
C4—C5	1.364 (3)	C20—C21	1.503 (3)
C4—C19	1.448 (3)	C20—H20A	0.9900
C6—C7	1.507 (3)	C20—H20B	0.9900
C7—C8	1.530 (3)	C21—H21A	0.9800
C7—H7A	0.9900	C21—H21B	0.9800
C7—H7B	0.9900	C21—H21C	0.9800
C8—C9	1.527 (3)
C1—O1—C5	118.72 (14)	C8—C10—H10B	109.5
C19—O5—C20	119.01 (15)	H10A—C10—H10B	109.5
C5—N1—H1A	120.0	C8—C10—H10C	109.5
C5—N1—H1B	120.0	H10A—C10—H10C	109.5
H1A—N1—H1B	120.0	H10B—C10—H10C	109.5
C12—N2—C13	112.20 (15)	C8—C11—H11A	109.5
C12—N2—H2	123.9	C8—C11—H11B	109.5
C13—N2—H2	123.9	H11A—C11—H11B	109.5
C2—C1—O1	123.13 (16)	C8—C11—H11C	109.5
C2—C1—C9	126.52 (17)	H11A—C11—H11C	109.5
O1—C1—C9	110.34 (15)	H11B—C11—H11C	109.5
C1—C2—C6	117.18 (16)	O3—C12—N2	125.94 (17)
C1—C2—C3	122.87 (16)	O3—C12—C3	125.73 (16)
C6—C2—C3	119.95 (15)	N2—C12—C3	108.32 (15)
C2—C3—C4	109.24 (14)	C14—C13—C18	122.13 (18)
C2—C3—C18	114.32 (14)	C14—C13—N2	128.45 (17)
C4—C3—C18	111.93 (14)	C18—C13—N2	109.39 (15)
C2—C3—C12	108.45 (14)	C13—C14—C15	117.47 (18)
C4—C3—C12	111.94 (14)	C13—C14—H14	121.3
C18—C3—C12	100.71 (14)	C15—C14—H14	121.3
C5—C4—C19	117.57 (16)	C16—C15—C14	121.19 (18)
C5—C4—C3	121.57 (16)	C16—C15—H15	119.4
C19—C4—C3	120.78 (15)	C14—C15—H15	119.4
N1—C5—C4	127.17 (17)	C15—C16—C17	120.47 (19)
N1—C5—O1	109.90 (15)	C15—C16—H16	119.8
C4—C5—O1	122.93 (16)	C17—C16—H16	119.8
O2—C6—C2	120.78 (16)	C18—C17—C16	118.64 (18)
O2—C6—C7	120.50 (17)	C18—C17—H17	120.7
C2—C6—C7	118.66 (16)	C16—C17—H17	120.7
C6—C7—C8	114.84 (16)	C17—C18—C13	120.07 (17)
C6—C7—H7A	108.6	C17—C18—C3	130.49 (17)
C8—C7—H7A	108.6	C13—C18—C3	109.33 (15)
C6—C7—H7B	108.6	O4—C19—O5	121.92 (17)
C8—C7—H7B	108.6	O4—C19—C4	126.41 (17)
H7A—C7—H7B	107.5	O5—C19—C4	111.66 (15)
C9—C8—C7	108.25 (15)	O5—C20—C21	106.56 (16)
C9—C8—C10	110.24 (16)	O5—C20—H20A	110.4
C7—C8—C10	109.82 (16)	C21—C20—H20A	110.4
C9—C8—C11	109.61 (15)	O5—C20—H20B	110.4
C7—C8—C11	109.16 (15)	C21—C20—H20B	110.4
C10—C8—C11	109.72 (15)	H20A—C20—H20B	108.6
C1—C9—C8	113.97 (15)	C20—C21—H21A	109.5
C1—C9—H9A	108.8	C20—C21—H21B	109.5
C8—C9—H9A	108.8	H21A—C21—H21B	109.5
C1—C9—H9B	108.8	C20—C21—H21C	109.5
C8—C9—H9B	108.8	H21A—C21—H21C	109.5
H9A—C9—H9B	107.7	H21B—C21—H21C	109.5
C8—C10—H10A	109.5
C5—O1—C1—C2	−9.1 (3)	C10—C8—C9—C1	−76.1 (2)
C5—O1—C1—C9	169.84 (15)	C11—C8—C9—C1	163.06 (16)
O1—C1—C2—C6	−177.43 (15)	C13—N2—C12—O3	−178.32 (17)
C9—C1—C2—C6	3.8 (3)	C13—N2—C12—C3	2.29 (19)
O1—C1—C2—C3	3.2 (3)	C2—C3—C12—O3	−61.1 (2)
C9—C1—C2—C3	−175.58 (17)	C4—C3—C12—O3	59.5 (2)
C1—C2—C3—C4	7.4 (2)	C18—C3—C12—O3	178.58 (17)
C6—C2—C3—C4	−171.98 (15)	C2—C3—C12—N2	118.30 (15)
C1—C2—C3—C18	−118.89 (19)	C4—C3—C12—N2	−121.10 (16)
C6—C2—C3—C18	61.7 (2)	C18—C3—C12—N2	−2.03 (17)
C1—C2—C3—C12	129.65 (18)	C12—N2—C13—C14	176.80 (18)
C6—C2—C3—C12	−49.7 (2)	C12—N2—C13—C18	−1.6 (2)
C2—C3—C4—C5	−13.0 (2)	C18—C13—C14—C15	1.0 (3)
C18—C3—C4—C5	114.60 (19)	N2—C13—C14—C15	−177.16 (17)
C12—C3—C4—C5	−133.18 (18)	C13—C14—C15—C16	0.6 (3)
C2—C3—C4—C19	170.14 (16)	C14—C15—C16—C17	−1.3 (3)
C18—C3—C4—C19	−62.2 (2)	C15—C16—C17—C18	0.5 (3)
C12—C3—C4—C19	50.0 (2)	C16—C17—C18—C13	1.1 (3)
C19—C4—C5—N1	4.7 (3)	C16—C17—C18—C3	176.77 (18)
C3—C4—C5—N1	−172.18 (17)	C14—C13—C18—C17	−1.8 (3)
C19—C4—C5—O1	−174.29 (16)	N2—C13—C18—C17	176.64 (16)
C3—C4—C5—O1	8.8 (3)	C14—C13—C18—C3	−178.38 (16)
C1—O1—C5—N1	−176.23 (15)	N2—C13—C18—C3	0.1 (2)
C1—O1—C5—C4	2.9 (3)	C2—C3—C18—C17	69.0 (2)
C1—C2—C6—O2	173.11 (17)	C4—C3—C18—C17	−55.8 (2)
C3—C2—C6—O2	−7.5 (3)	C12—C3—C18—C17	−174.93 (18)
C1—C2—C6—C7	−9.4 (2)	C2—C3—C18—C13	−114.90 (17)
C3—C2—C6—C7	170.05 (16)	C4—C3—C18—C13	120.22 (16)
O2—C6—C7—C8	−147.85 (17)	C12—C3—C18—C13	1.13 (18)
C2—C6—C7—C8	34.6 (2)	C20—O5—C19—O4	7.4 (3)
C6—C7—C8—C9	−50.6 (2)	C20—O5—C19—C4	−171.23 (16)
C6—C7—C8—C10	69.8 (2)	C5—C4—C19—O4	−4.3 (3)
C6—C7—C8—C11	−169.86 (16)	C3—C4—C19—O4	172.61 (17)
C2—C1—C9—C8	−23.1 (3)	C5—C4—C19—O5	174.22 (16)
O1—C1—C9—C8	158.03 (15)	C3—C4—C19—O5	−8.8 (2)
C7—C8—C9—C1	44.1 (2)	C19—O5—C20—C21	154.05 (17)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O4	0.88	2.03	2.658 (2)	128
N1—H1B···O3i	0.88	1.92	2.794 (2)	175
N2—H2···O2ii	0.88	2.04	2.8435 (19)	152
C16—H16···O4iii	0.95	2.54	3.448 (2)	159

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯O4	0.88	2.03	2.658 (2)	128
N1—H1B⋯O3i	0.88	1.92	2.794 (2)	175
N2—H2⋯O2ii	0.88	2.04	2.8435 (19)	152
C16—H16⋯O4iii	0.95	2.54	3.448 (2)	159

Symmetry codes: (i) ; (ii) ; (iii) .