Ethyl 7-hydr­oxy-1H-indole-1-carboxyl­ate

The two independent mol­ecules in the asymmetric unit of the title compound, C₁₁H₁₁NO₃, show similar conformations. In both mol­ecules, there is an intra­molecular O—H...O hydrogen bond and the ethoxy­carbonyl substituent is almost coplanar with the indole ring system. C—H...O and C—H...π inter­actions link the mol­ecules into a ladder-like structure along the b axis.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.035
• wR factor = 0.089
• Data-to-parameter ratio = 16.4

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT063_ALERT_3_C Crystal Probably too Large for Beam Size .......       0.69 mm
PLAT220_ALERT_2_C Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       2.65 Ratio

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

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 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: APEX2 (Bruker, 2005); cell refinement: APEX2; data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 1998); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2003).

Ethyl 7-hydroxy-1H-indole-1-carboxylate

Crystal data

C11H11NO3	F(000) = 1728
Mr = 205.21	Dx = 1.365 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 9895 reflections
a = 29.6743 (4) Å	θ = 2.4–37.9°
b = 7.7695 (1) Å	µ = 0.10 mm^−1
c = 21.7331 (3) Å	T = 100 K
β = 127.118 (1)°	Block, colourless
V = 3995.48 (11) Å^3	0.69 × 0.36 × 0.23 mm
Z = 16

Data collection

Bruker SMART APEX2 CCD area-detector diffractometer	4536 independent reflections
Radiation source: fine-focus sealed tube	4041 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.028
Detector resolution: 8.33 pixels mm^-1	θmax = 27.5°, θmin = 1.7°
ω scans	h = −38→36
Absorption correction: multi-scan (SADABS; Bruker, 2005)	k = −9→10
Tmin = 0.902, Tmax = 0.977	l = −28→28
23267 measured reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.035	H-atom parameters constrained
wR(F^2) = 0.089	w = 1/[σ^2(Fo^2) + (0.0381P)^2 + 3.1532P] where P = (Fo^2 + 2Fc^2)/3
S = 1.03	(Δ/σ)max = 0.001
4536 reflections	Δρmax = 0.26 e Å^−3
276 parameters	Δρmin = −0.21 e Å^−3
0 restraints	Extinction correction: SHELXTL, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.00061 (11)

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
O1A	0.09837 (3)	0.69226 (10)	0.05051 (4)	0.02269 (18)
O2A	0.15730 (3)	0.54423 (10)	0.16064 (4)	0.02248 (18)
O3A	0.00350 (3)	0.63918 (10)	−0.08580 (4)	0.02290 (18)
H3A	0.0310	0.6752	−0.0442	0.034*
N1A	0.09057 (4)	0.39911 (12)	0.05519 (5)	0.01815 (19)
C1A	0.11393 (5)	0.24223 (14)	0.09503 (6)	0.0206 (2)
H1A	0.1457	0.2319	0.1461	0.025*
C2A	0.08336 (5)	0.11028 (14)	0.04794 (7)	0.0218 (2)
H2A	0.0904	−0.0058	0.0608	0.026*
C3A	0.03767 (5)	0.17939 (14)	−0.02608 (6)	0.0199 (2)
C4A	−0.00569 (5)	0.09878 (15)	−0.09475 (7)	0.0232 (2)
H4A	−0.0085	−0.0206	−0.0983	0.028*
C5A	−0.04410 (5)	0.20130 (16)	−0.15704 (7)	0.0245 (2)
H5A	−0.0732	0.1503	−0.2033	0.029*
C6A	−0.03989 (5)	0.38048 (15)	−0.15164 (6)	0.0223 (2)
H6A	−0.0667	0.4461	−0.1945	0.027*
C7A	0.00305 (5)	0.46416 (14)	−0.08439 (6)	0.0189 (2)
C8A	0.04235 (4)	0.36006 (14)	−0.02086 (6)	0.0178 (2)
C9A	0.11440 (5)	0.55716 (14)	0.08639 (6)	0.0189 (2)
C10A	0.18517 (5)	0.70441 (16)	0.20056 (7)	0.0265 (3)
H10A	0.1576	0.7895	0.1907	0.032*
H10B	0.2064	0.7501	0.1835	0.032*
C11A	0.22403 (7)	0.6606 (2)	0.28463 (8)	0.0471 (4)
H11A	0.2448	0.7614	0.3137	0.071*
H11B	0.2499	0.5726	0.2931	0.071*
H11C	0.2023	0.6197	0.3010	0.071*
O1B	0.21034 (3)	0.50527 (11)	0.57214 (5)	0.02549 (19)
O2B	0.18296 (3)	0.58053 (11)	0.45426 (5)	0.02482 (19)
O3B	0.29969 (4)	0.38471 (14)	0.70062 (5)	0.0336 (2)
H3B	0.2687	0.4199	0.6639	0.050*
N1B	0.26764 (4)	0.45789 (13)	0.53556 (5)	0.0219 (2)
C1B	0.27593 (5)	0.46283 (16)	0.47821 (7)	0.0257 (3)
H1B	0.2495	0.5012	0.4279	0.031*
C2B	0.32778 (5)	0.40372 (16)	0.50719 (7)	0.0259 (3)
H2B	0.3430	0.3940	0.4805	0.031*
C3B	0.35569 (5)	0.35788 (15)	0.58680 (7)	0.0227 (2)
C4B	0.41001 (5)	0.29559 (16)	0.64314 (7)	0.0265 (3)
H4B	0.4352	0.2748	0.6320	0.032*
C5B	0.42508 (5)	0.26587 (16)	0.71601 (7)	0.0279 (3)
H5B	0.4611	0.2248	0.7545	0.033*
C6B	0.38733 (5)	0.29625 (16)	0.73303 (7)	0.0262 (3)
H6B	0.3988	0.2740	0.7826	0.031*
C7B	0.33320 (5)	0.35870 (15)	0.67816 (7)	0.0233 (2)
C8B	0.31761 (5)	0.39094 (14)	0.60402 (6)	0.0205 (2)
C9B	0.21893 (5)	0.51434 (15)	0.52407 (6)	0.0213 (2)
C10B	0.12858 (5)	0.63411 (16)	0.43547 (7)	0.0247 (2)
H10C	0.1342	0.7229	0.4709	0.030*
H10D	0.1099	0.5370	0.4393	0.030*
C11B	0.09350 (5)	0.70196 (17)	0.35441 (7)	0.0293 (3)
H11D	0.0578	0.7413	0.3405	0.044*
H11E	0.0874	0.6120	0.3198	0.044*
H11F	0.1129	0.7960	0.3511	0.044*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1A	0.0271 (4)	0.0154 (4)	0.0247 (4)	−0.0004 (3)	0.0152 (3)	0.0008 (3)
O2A	0.0251 (4)	0.0189 (4)	0.0210 (4)	−0.0011 (3)	0.0126 (3)	−0.0015 (3)
O3A	0.0270 (4)	0.0156 (4)	0.0230 (4)	0.0013 (3)	0.0135 (3)	0.0021 (3)
N1A	0.0216 (4)	0.0150 (5)	0.0202 (4)	0.0010 (3)	0.0139 (4)	0.0017 (3)
C1A	0.0242 (5)	0.0176 (5)	0.0243 (5)	0.0041 (4)	0.0169 (5)	0.0051 (4)
C2A	0.0274 (6)	0.0152 (5)	0.0295 (6)	0.0024 (4)	0.0208 (5)	0.0036 (4)
C3A	0.0244 (5)	0.0166 (5)	0.0259 (5)	−0.0001 (4)	0.0191 (5)	0.0006 (4)
C4A	0.0288 (6)	0.0166 (6)	0.0293 (6)	−0.0039 (4)	0.0202 (5)	−0.0035 (4)
C5A	0.0252 (6)	0.0253 (6)	0.0246 (5)	−0.0054 (5)	0.0158 (5)	−0.0056 (4)
C6A	0.0235 (5)	0.0237 (6)	0.0212 (5)	0.0014 (4)	0.0143 (5)	0.0018 (4)
C7A	0.0227 (5)	0.0166 (5)	0.0232 (5)	0.0011 (4)	0.0170 (5)	0.0011 (4)
C8A	0.0209 (5)	0.0168 (5)	0.0208 (5)	−0.0012 (4)	0.0152 (4)	−0.0011 (4)
C9A	0.0218 (5)	0.0181 (5)	0.0221 (5)	0.0003 (4)	0.0161 (5)	−0.0005 (4)
C10A	0.0264 (6)	0.0217 (6)	0.0277 (6)	−0.0027 (5)	0.0143 (5)	−0.0065 (4)
C11A	0.0444 (8)	0.0374 (8)	0.0278 (7)	0.0016 (7)	0.0051 (6)	−0.0073 (6)
O1B	0.0253 (4)	0.0326 (5)	0.0241 (4)	0.0018 (4)	0.0178 (4)	−0.0009 (3)
O2B	0.0229 (4)	0.0307 (5)	0.0240 (4)	0.0036 (3)	0.0158 (3)	0.0016 (3)
O3B	0.0307 (5)	0.0507 (6)	0.0277 (4)	0.0124 (4)	0.0219 (4)	0.0097 (4)
N1B	0.0228 (5)	0.0252 (5)	0.0219 (5)	0.0004 (4)	0.0158 (4)	−0.0001 (4)
C1B	0.0291 (6)	0.0306 (7)	0.0239 (5)	−0.0005 (5)	0.0194 (5)	0.0003 (5)
C2B	0.0281 (6)	0.0299 (7)	0.0284 (6)	−0.0020 (5)	0.0216 (5)	−0.0025 (5)
C3B	0.0245 (5)	0.0211 (6)	0.0274 (6)	−0.0036 (4)	0.0183 (5)	−0.0043 (4)
C4B	0.0234 (6)	0.0281 (6)	0.0335 (6)	−0.0012 (5)	0.0201 (5)	−0.0031 (5)
C5B	0.0222 (6)	0.0282 (7)	0.0296 (6)	0.0006 (5)	0.0137 (5)	0.0000 (5)
C6B	0.0272 (6)	0.0276 (6)	0.0243 (6)	0.0000 (5)	0.0159 (5)	0.0005 (4)
C7B	0.0263 (6)	0.0229 (6)	0.0264 (5)	−0.0012 (5)	0.0188 (5)	−0.0015 (4)
C8B	0.0209 (5)	0.0186 (6)	0.0235 (5)	−0.0020 (4)	0.0141 (5)	−0.0024 (4)
C9B	0.0226 (5)	0.0200 (6)	0.0236 (5)	−0.0023 (4)	0.0151 (5)	−0.0033 (4)
C10B	0.0212 (5)	0.0298 (6)	0.0256 (6)	0.0020 (5)	0.0154 (5)	−0.0026 (5)
C11B	0.0288 (6)	0.0300 (7)	0.0270 (6)	0.0030 (5)	0.0156 (5)	0.0002 (5)

Geometric parameters (Å, º)

O1A—C9A	1.2200 (13)	O1B—C9B	1.2179 (13)
O2A—C9A	1.3249 (13)	O2B—C9B	1.3232 (14)
O2A—C10A	1.4559 (14)	O2B—C10B	1.4660 (13)
O3A—C7A	1.3604 (14)	O3B—C7B	1.3613 (14)
O3A—H3A	0.82	O3B—H3B	0.82
N1A—C9A	1.3745 (14)	N1B—C9B	1.3815 (15)
N1A—C1A	1.4112 (14)	N1B—C1B	1.4091 (14)
N1A—C8A	1.4202 (14)	N1B—C8B	1.4215 (14)
C1A—C2A	1.3420 (16)	C1B—C2B	1.3436 (17)
C1A—H1A	0.93	C1B—H1B	0.93
C2A—C3A	1.4430 (16)	C2B—C3B	1.4411 (16)
C2A—H2A	0.93	C2B—H2B	0.93
C3A—C4A	1.3992 (16)	C3B—C4B	1.3962 (17)
C3A—C8A	1.4084 (16)	C3B—C8B	1.4117 (15)
C4A—C5A	1.3798 (17)	C4B—C5B	1.3806 (17)
C4A—H4A	0.93	C4B—H4B	0.93
C5A—C6A	1.3963 (17)	C5B—C6B	1.3956 (17)
C5A—H5A	0.93	C5B—H5B	0.93
C6A—C7A	1.3910 (16)	C6B—C7B	1.3878 (17)
C6A—H6A	0.93	C6B—H6B	0.93
C7A—C8A	1.4060 (15)	C7B—C8B	1.4049 (15)
C10A—C11A	1.4969 (18)	C10B—C11B	1.5005 (16)
C10A—H10A	0.97	C10B—H10C	0.97
C10A—H10B	0.97	C10B—H10D	0.97
C11A—H11A	0.96	C11B—H11D	0.96
C11A—H11B	0.96	C11B—H11E	0.96
C11A—H11C	0.96	C11B—H11F	0.96
C9A—O2A—C10A	116.34 (9)	C9B—O2B—C10B	114.86 (9)
C7A—O3A—H3A	109.5	C7B—O3B—H3B	109.5
C9A—N1A—C1A	123.57 (9)	C9B—N1B—C1B	123.62 (10)
C9A—N1A—C8A	128.47 (9)	C9B—N1B—C8B	128.48 (9)
C1A—N1A—C8A	107.85 (9)	C1B—N1B—C8B	107.88 (9)
C2A—C1A—N1A	109.64 (10)	C2B—C1B—N1B	109.74 (10)
C2A—C1A—H1A	125.2	C2B—C1B—H1B	125.1
N1A—C1A—H1A	125.2	N1B—C1B—H1B	125.1
C1A—C2A—C3A	108.29 (10)	C1B—C2B—C3B	108.25 (10)
C1A—C2A—H2A	125.9	C1B—C2B—H2B	125.9
C3A—C2A—H2A	125.9	C3B—C2B—H2B	125.9
C4A—C3A—C8A	120.97 (10)	C4B—C3B—C8B	121.03 (11)
C4A—C3A—C2A	131.55 (11)	C4B—C3B—C2B	131.42 (11)
C8A—C3A—C2A	107.49 (10)	C8B—C3B—C2B	107.53 (10)
C5A—C4A—C3A	118.14 (11)	C5B—C4B—C3B	117.87 (11)
C5A—C4A—H4A	120.9	C5B—C4B—H4B	121.1
C3A—C4A—H4A	120.9	C3B—C4B—H4B	121.1
C4A—C5A—C6A	120.94 (11)	C4B—C5B—C6B	121.29 (11)
C4A—C5A—H5A	119.5	C4B—C5B—H5B	119.4
C6A—C5A—H5A	119.5	C6B—C5B—H5B	119.4
C7A—C6A—C5A	122.21 (11)	C7B—C6B—C5B	121.97 (11)
C7A—C6A—H6A	118.9	C7B—C6B—H6B	119.0
C5A—C6A—H6A	118.9	C5B—C6B—H6B	119.0
O3A—C7A—C6A	117.30 (10)	O3B—C7B—C6B	117.45 (10)
O3A—C7A—C8A	125.70 (10)	O3B—C7B—C8B	125.36 (11)
C6A—C7A—C8A	117.00 (10)	C6B—C7B—C8B	117.19 (10)
C7A—C8A—C3A	120.74 (10)	C7B—C8B—C3B	120.63 (11)
C7A—C8A—N1A	132.53 (10)	C7B—C8B—N1B	132.78 (10)
C3A—C8A—N1A	106.72 (9)	C3B—C8B—N1B	106.59 (9)
O1A—C9A—O2A	124.14 (10)	O1B—C9B—O2B	124.37 (10)
O1A—C9A—N1A	124.56 (10)	O1B—C9B—N1B	124.37 (10)
O2A—C9A—N1A	111.30 (9)	O2B—C9B—N1B	111.26 (9)
O2A—C10A—C11A	105.97 (10)	O2B—C10B—C11B	107.09 (9)
O2A—C10A—H10A	110.5	O2B—C10B—H10C	110.3
C11A—C10A—H10A	110.5	C11B—C10B—H10C	110.3
O2A—C10A—H10B	110.5	O2B—C10B—H10D	110.3
C11A—C10A—H10B	110.5	C11B—C10B—H10D	110.3
H10A—C10A—H10B	108.7	H10C—C10B—H10D	108.6
C10A—C11A—H11A	109.5	C10B—C11B—H11D	109.5
C10A—C11A—H11B	109.5	C10B—C11B—H11E	109.5
H11A—C11A—H11B	109.5	H11D—C11B—H11E	109.5
C10A—C11A—H11C	109.5	C10B—C11B—H11F	109.5
H11A—C11A—H11C	109.5	H11D—C11B—H11F	109.5
H11B—C11A—H11C	109.5	H11E—C11B—H11F	109.5
C9A—N1A—C1A—C2A	−175.86 (10)	C9B—N1B—C1B—C2B	178.36 (11)
C8A—N1A—C1A—C2A	0.57 (12)	C8B—N1B—C1B—C2B	−0.17 (14)
N1A—C1A—C2A—C3A	−0.27 (13)	N1B—C1B—C2B—C3B	−0.26 (14)
C1A—C2A—C3A—C4A	179.58 (11)	C1B—C2B—C3B—C4B	−177.90 (13)
C1A—C2A—C3A—C8A	−0.13 (13)	C1B—C2B—C3B—C8B	0.59 (14)
C8A—C3A—C4A—C5A	−0.66 (16)	C8B—C3B—C4B—C5B	0.59 (18)
C2A—C3A—C4A—C5A	179.66 (11)	C2B—C3B—C4B—C5B	178.90 (13)
C3A—C4A—C5A—C6A	−0.11 (17)	C3B—C4B—C5B—C6B	0.26 (19)
C4A—C5A—C6A—C7A	0.75 (18)	C4B—C5B—C6B—C7B	−0.5 (2)
C5A—C6A—C7A—O3A	179.26 (10)	C5B—C6B—C7B—O3B	−179.72 (12)
C5A—C6A—C7A—C8A	−0.56 (16)	C5B—C6B—C7B—C8B	−0.12 (18)
O3A—C7A—C8A—C3A	179.98 (10)	O3B—C7B—C8B—C3B	−179.48 (11)
C6A—C7A—C8A—C3A	−0.22 (15)	C6B—C7B—C8B—C3B	0.95 (17)
O3A—C7A—C8A—N1A	0.13 (19)	O3B—C7B—C8B—N1B	1.5 (2)
C6A—C7A—C8A—N1A	179.93 (11)	C6B—C7B—C8B—N1B	−178.03 (12)
C4A—C3A—C8A—C7A	0.84 (16)	C4B—C3B—C8B—C7B	−1.22 (18)
C2A—C3A—C8A—C7A	−179.41 (9)	C2B—C3B—C8B—C7B	−179.89 (11)
C4A—C3A—C8A—N1A	−179.28 (10)	C4B—C3B—C8B—N1B	178.00 (11)
C2A—C3A—C8A—N1A	0.47 (12)	C2B—C3B—C8B—N1B	−0.68 (13)
C9A—N1A—C8A—C7A	−4.57 (19)	C9B—N1B—C8B—C7B	1.2 (2)
C1A—N1A—C8A—C7A	179.23 (11)	C1B—N1B—C8B—C7B	179.61 (12)
C9A—N1A—C8A—C3A	175.56 (10)	C9B—N1B—C8B—C3B	−177.91 (11)
C1A—N1A—C8A—C3A	−0.63 (11)	C1B—N1B—C8B—C3B	0.53 (12)
C10A—O2A—C9A—O1A	1.58 (15)	C10B—O2B—C9B—O1B	−3.97 (16)
C10A—O2A—C9A—N1A	−178.59 (9)	C10B—O2B—C9B—N1B	176.43 (9)
C1A—N1A—C9A—O1A	171.90 (10)	C1B—N1B—C9B—O1B	177.27 (11)
C8A—N1A—C9A—O1A	−3.76 (18)	C8B—N1B—C9B—O1B	−4.52 (19)
C1A—N1A—C9A—O2A	−7.93 (14)	C1B—N1B—C9B—O2B	−3.13 (16)
C8A—N1A—C9A—O2A	176.42 (9)	C8B—N1B—C9B—O2B	175.08 (10)
C9A—O2A—C10A—C11A	169.82 (11)	C9B—O2B—C10B—C11B	−178.96 (10)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3A—H3A···O1A	0.82	1.81	2.6088 (11)	164
O3B—H3B···O1B	0.82	1.80	2.6017 (13)	165
C2A—H2A···O1A^i	0.93	2.38	3.2741 (14)	161
C10B—H10C···Cg2^ii	0.97	2.78	3.4151 (17)	124
C11B—H11D···Cg3^ii	0.96	2.94	3.6826 (18)	135
C11B—H11F···Cg1^iii	0.96	2.99	3.8653 (15)	152

Symmetry codes: (i) x, y−1, z; (ii) −x+1/2, y+3/2, −z+1/2; (iii) −x+1/2, −y+3/2, −z+1.