Ethyl 7-formyl­-1H-indole-1-carboxyl­ate

The non-H atoms of the title mol­ecule, C₁₂H₁₁NO₃, are nearly coplanar, with an r.m.s deviation of 0.054 Å. There are two intra­molecular C—H...O hydrogen bonds. Pairs of the mol­ecules are linked into centrosymmetric dimers via inter­molecular C—H...π inter­actions. The dimers are stacked along the a axis with weak π–π inter­actions.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.059
• wR factor = 0.190
• Data-to-parameter ratio = 21.3

checkCIF/PLATON results

No syntax errors found



Alert level C
ABSTM02_ALERT_3_C  The ratio of expected to reported Tmax/Tmin(RR') is < 0.90
            Tmin and Tmax reported:      0.825     0.989
            Tmin(prime) and Tmax expected:      0.966     0.989
            RR(prime) =      0.854
            Please check that your absorption correction is appropriate.
PLAT026_ALERT_3_C Ratio Observed / Unique Reflections too Low ....         44 Perc.
PLAT061_ALERT_3_C Tmax/Tmin Range Test RR' too Large .............       0.85
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for        C12
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C7
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C9

Alert level G
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K

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

   2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 ALERT type 2 Indicator that the structure model may be wrong or deficient
   3 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 (Sheldrick, 1998); molecular graphics: SHELXTL (Sheldrick, 1998); software used to prepare material for publication: SHELXTL and PLATON (Spek, 2003).

1- Carbethoxy-7-formylindole

Crystal data

C12H11NO3	F(000) = 456
Mr = 217.22	Dx = 1.340 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2085 reflections
a = 7.6525 (2) Å	θ = 3.0–20.1°
b = 19.2946 (6) Å	µ = 0.10 mm^−1
c = 8.0851 (2) Å	T = 293 K
β = 115.547 (1)°	Block, colourless
V = 1077.07 (5) Å^3	0.35 × 0.20 × 0.11 mm
Z = 4

Data collection

Bruker SMART APEX2 CCD area-detector diffractometer	3127 independent reflections
Radiation source: fine-focus sealed tube	1382 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.044
Detector resolution: 8.33 pixels mm^-1	θmax = 30.0°, θmin = 2.1°
ω scans	h = −10→9
Absorption correction: multi-scan (SADABS; Bruker, 2005)	k = −26→24
Tmin = 0.825, Tmax = 0.989	l = −11→11
15320 measured reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.059	H-atom parameters constrained
wR(F^2) = 0.190	w = 1/[σ^2(Fo^2) + (0.085P)^2 + 0.0079P] where P = (Fo^2 + 2Fc^2)/3
S = 1.04	(Δ/σ)max = 0.001
3127 reflections	Δρmax = 0.26 e Å^−3
147 parameters	Δρmin = −0.26 e Å^−3
0 restraints	Extinction correction: SHELXTL, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
32 constraints	Extinction coefficient: 0.015 (4)
Primary atom site location: structure-invariant direct methods

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
O1	0.2450 (3)	0.47693 (8)	0.2538 (2)	0.0897 (6)
O2	0.1983 (2)	0.37585 (7)	0.10656 (18)	0.0658 (5)
O3	0.3619 (3)	0.66176 (9)	0.3035 (2)	0.1126 (7)
N1	0.2327 (2)	0.47077 (8)	−0.0330 (2)	0.0591 (5)
C1	0.1961 (3)	0.43126 (12)	−0.1902 (3)	0.0716 (6)
H1	0.1696	0.3840	−0.2016	0.086*
C2	0.2049 (3)	0.47122 (12)	−0.3205 (3)	0.0729 (7)
H2	0.1853	0.4568	−0.4370	0.087*
C3	0.2494 (3)	0.53974 (11)	−0.2506 (2)	0.0593 (6)
C4	0.2766 (3)	0.60073 (13)	−0.3289 (3)	0.0730 (7)
H4	0.2676	0.6006	−0.4474	0.088*
C5	0.3164 (3)	0.66041 (13)	−0.2298 (3)	0.0773 (7)
H5	0.3310	0.7016	−0.2822	0.093*
C6	0.3354 (3)	0.66021 (12)	−0.0525 (3)	0.0707 (6)
H6	0.3652	0.7017	0.0125	0.085*
C7	0.3122 (3)	0.60097 (10)	0.0340 (3)	0.0583 (5)
C8	0.2682 (3)	0.53959 (10)	−0.0690 (2)	0.0538 (5)
C9	0.2262 (3)	0.44345 (11)	0.1230 (3)	0.0553 (5)
C10	0.1960 (4)	0.34024 (11)	0.2639 (3)	0.0756 (7)
H10A	0.0925	0.3581	0.2908	0.091*
H10B	0.3181	0.3469	0.3709	0.091*
C11	0.1645 (5)	0.26536 (12)	0.2158 (4)	0.1008 (9)
H11A	0.1613	0.2400	0.3166	0.151*
H11B	0.2682	0.2483	0.1903	0.151*
H11C	0.0436	0.2595	0.1094	0.151*
C12	0.3466 (5)	0.61013 (14)	0.2252 (3)	0.1060 (10)
H12	0.3576	0.5698	0.2919	0.127*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.1491 (16)	0.0700 (10)	0.0777 (10)	−0.0145 (9)	0.0750 (11)	−0.0121 (8)
O2	0.0863 (10)	0.0531 (9)	0.0610 (9)	0.0003 (7)	0.0346 (8)	0.0045 (7)
O3	0.191 (2)	0.0737 (12)	0.0784 (11)	−0.0082 (12)	0.0629 (13)	−0.0191 (10)
N1	0.0831 (12)	0.0497 (10)	0.0441 (8)	0.0035 (8)	0.0270 (8)	−0.0013 (7)
C1	0.0984 (17)	0.0564 (13)	0.0537 (12)	0.0067 (11)	0.0270 (11)	−0.0089 (10)
C2	0.0962 (16)	0.0749 (16)	0.0464 (11)	0.0173 (12)	0.0295 (11)	−0.0038 (11)
C3	0.0656 (12)	0.0686 (14)	0.0456 (10)	0.0101 (10)	0.0259 (9)	0.0042 (10)
C4	0.0839 (15)	0.0879 (18)	0.0548 (12)	0.0029 (12)	0.0370 (11)	0.0123 (12)
C5	0.0932 (17)	0.0739 (16)	0.0731 (15)	−0.0060 (12)	0.0436 (13)	0.0146 (13)
C6	0.0813 (15)	0.0627 (14)	0.0680 (13)	−0.0073 (11)	0.0322 (11)	0.0017 (11)
C7	0.0697 (13)	0.0556 (12)	0.0537 (11)	−0.0032 (9)	0.0303 (10)	−0.0012 (9)
C8	0.0609 (11)	0.0545 (12)	0.0481 (10)	0.0045 (9)	0.0255 (9)	0.0025 (9)
C9	0.0606 (12)	0.0543 (13)	0.0538 (11)	0.0010 (9)	0.0271 (9)	−0.0007 (9)
C10	0.0987 (17)	0.0681 (15)	0.0685 (14)	0.0007 (12)	0.0440 (13)	0.0098 (11)
C11	0.155 (3)	0.0605 (15)	0.110 (2)	0.0024 (16)	0.079 (2)	0.0120 (15)
C12	0.197 (3)	0.0633 (16)	0.0731 (16)	−0.0381 (17)	0.0723 (19)	−0.0195 (13)

Geometric parameters (Å, º)

O1—C9	1.193 (2)	C4—H4	0.93
O2—C9	1.319 (2)	C5—C6	1.377 (3)
O2—C10	1.453 (2)	C5—H5	0.93
O3—C12	1.159 (3)	C6—C7	1.391 (3)
N1—C9	1.388 (2)	C6—H6	0.93
N1—C1	1.403 (2)	C7—C8	1.403 (3)
N1—C8	1.411 (2)	C7—C12	1.463 (3)
C1—C2	1.331 (3)	C10—C11	1.489 (3)
C1—H1	0.93	C10—H10A	0.97
C2—C3	1.420 (3)	C10—H10B	0.97
C2—H2	0.93	C11—H11A	0.96
C3—C4	1.394 (3)	C11—H11B	0.96
C3—C8	1.412 (3)	C11—H11C	0.96
C4—C5	1.360 (3)	C12—H12	0.93
C9—O2—C10	116.22 (15)	C6—C7—C12	115.36 (19)
C9—N1—C1	123.07 (17)	C8—C7—C12	128.13 (19)
C9—N1—C8	129.12 (16)	C7—C8—N1	133.64 (17)
C1—N1—C8	107.78 (16)	C7—C8—C3	120.43 (18)
C2—C1—N1	110.13 (19)	N1—C8—C3	105.92 (16)
C2—C1—H1	124.9	O1—C9—O2	125.23 (18)
N1—C1—H1	124.9	O1—C9—N1	124.18 (19)
C1—C2—C3	108.04 (18)	O2—C9—N1	110.59 (16)
C1—C2—H2	126.0	O2—C10—C11	106.95 (18)
C3—C2—H2	126.0	O2—C10—H10A	110.3
C4—C3—C8	120.39 (19)	C11—C10—H10A	110.3
C4—C3—C2	131.5 (2)	O2—C10—H10B	110.3
C8—C3—C2	108.12 (18)	C11—C10—H10B	110.3
C5—C4—C3	119.1 (2)	H10A—C10—H10B	108.6
C5—C4—H4	120.4	C10—C11—H11A	109.5
C3—C4—H4	120.4	C10—C11—H11B	109.5
C4—C5—C6	120.5 (2)	H11A—C11—H11B	109.5
C4—C5—H5	119.8	C10—C11—H11C	109.5
C6—C5—H5	119.8	H11A—C11—H11C	109.5
C5—C6—C7	123.1 (2)	H11B—C11—H11C	109.5
C5—C6—H6	118.4	O3—C12—C7	127.7 (2)
C7—C6—H6	118.4	O3—C12—H12	116.2
C6—C7—C8	116.43 (19)	C7—C12—H12	116.2
C9—N1—C1—C2	177.58 (18)	C1—N1—C8—C7	−180.0 (2)
C8—N1—C1—C2	−0.6 (2)	C9—N1—C8—C3	−177.36 (17)
N1—C1—C2—C3	0.3 (3)	C1—N1—C8—C3	0.7 (2)
C1—C2—C3—C4	179.4 (2)	C4—C3—C8—C7	0.7 (3)
C1—C2—C3—C8	0.2 (3)	C2—C3—C8—C7	−179.97 (18)
C8—C3—C4—C5	−1.7 (3)	C4—C3—C8—N1	−179.84 (17)
C2—C3—C4—C5	179.2 (2)	C2—C3—C8—N1	−0.5 (2)
C3—C4—C5—C6	1.9 (3)	C10—O2—C9—O1	−1.7 (3)
C4—C5—C6—C7	−1.3 (4)	C10—O2—C9—N1	177.72 (16)
C5—C6—C7—C8	0.3 (3)	C1—N1—C9—O1	−175.20 (19)
C5—C6—C7—C12	177.3 (2)	C8—N1—C9—O1	2.6 (3)
C6—C7—C8—N1	−179.3 (2)	C1—N1—C9—O2	5.4 (3)
C12—C7—C8—N1	4.1 (4)	C8—N1—C9—O2	−176.85 (17)
C6—C7—C8—C3	0.0 (3)	C9—O2—C10—C11	−179.5 (2)
C12—C7—C8—C3	−176.6 (2)	C6—C7—C12—O3	12.6 (5)
C9—N1—C8—C7	2.0 (4)	C8—C7—C12—O3	−170.8 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C6—H6···O3	0.93	2.49	2.797 (3)	100
C12—H12···O1	0.93	1.95	2.724 (3)	139
C10—H10A···Cg1^i	0.97	2.78	3.632 (3)	146

Symmetry code: (i) −x, −y+1, −z.