(1R,2R)-Ethyl 1-azido-2-hydroxy-2,3-dihydro-1H-pyrrolo[1,2-a]indole-9-carboxyl­ate

The crystal structure of the title compound, C₁₄H₁₄N₄O₃, confirms both the sites of attachment and the trans arrangement of the hydroxy and azide substituents, and reveals intermolecular hydrogen bonding between OH and C=O units, resulting in a chain of molecules along the b axis.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.032
• wR factor = 0.083
• Data-to-parameter ratio = 10.0

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT199_ALERT_1_C Check the Reported cell_measurement_temperature         293
PLAT200_ALERT_1_C Check the Reported cell_ambient_temperature ....        293
PLAT230_ALERT_2_C Hirshfeld Test Diff for    N1     -   N2      ..       6.46 su
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         N2

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           27.99
           From the CIF: _reflns_number_total               1968
           Count of symmetry unique reflns         1969
           Completeness (_total/calc)             99.95%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present         no

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

   2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 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
   1 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: SMART-NT (Bruker, 1998); cell refinement: SAINT-Plus (Bruker, 1999); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXTL (Bruker, 1999); program(s) used to refine structure: SHELXTL; molecular graphics: PLATON (Spek, 2003) and SCHAKAL97 (Keller, 1997); software used to prepare material for publication: SHELXTL.

(1R,2R)-Ethyl 1-azido-2-hydroxy-2,3-dihydro-1H-pyrrolo[1,2-a]indole-9-carboxylate

Crystal data

C14H14N4O3	Dx = 1.366 Mg m^−3
Mr = 286.29	Melting point: 402.5 K
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 809 reflections
a = 5.8464 (9) Å	θ = 2.8–24.4°
b = 8.8422 (14) Å	µ = 0.10 mm^−1
c = 26.927 (4) Å	T = 293 K
V = 1392.0 (4) Å^3	Plate, yellow–brown
Z = 4	0.40 × 0.24 × 0.10 mm
F(000) = 600

Data collection

Bruker SMART CCD area-detector diffractometer	1439 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.030
Graphite monochromator	θmax = 28.0°, θmin = 1.5°
φ and ω scans	h = −7→7
9551 measured reflections	k = −11→9
1968 independent reflections	l = −35→33

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)] = 0.032	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.083	w = 1/[σ^2(Fo^2) + (0.0435P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.09	(Δ/σ)max = 0.005
1968 reflections	Δρmax = 0.15 e Å^−3
196 parameters	Δρmin = −0.11 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: 0.0084 (19)

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
C1	0.3739 (4)	0.26103 (19)	0.08722 (6)	0.0412 (4)
H1	0.5387	0.2412	0.0889	0.049*
C2	0.3150 (3)	0.4231 (2)	0.10428 (7)	0.0418 (5)
H2	0.3074	0.4922	0.0759	0.050*
C3	0.0807 (4)	0.4099 (2)	0.12984 (7)	0.0447 (5)
H3A	0.0705	0.4761	0.1585	0.054*
H3B	−0.0429	0.4331	0.1071	0.054*
C4A	−0.0537 (3)	0.1628 (2)	0.17635 (6)	0.0390 (4)
C5	−0.2414 (4)	0.2003 (2)	0.20535 (7)	0.0485 (5)
H5	−0.3008	0.2978	0.2056	0.058*
C6	−0.3362 (4)	0.0874 (3)	0.23380 (8)	0.0567 (6)
H6	−0.4624	0.1087	0.2536	0.068*
C7	−0.2457 (4)	−0.0589 (2)	0.23335 (8)	0.0569 (6)
H7	−0.3121	−0.1325	0.2534	0.068*
C8	−0.0614 (4)	−0.0972 (2)	0.20424 (7)	0.0489 (5)
H8	−0.0044	−0.1955	0.2042	0.059*
C8A	0.0389 (4)	0.0153 (2)	0.17457 (6)	0.0391 (4)
C9	0.2288 (4)	0.01867 (19)	0.14045 (6)	0.0379 (4)
C9A	0.2433 (3)	0.16560 (19)	0.12315 (6)	0.0361 (4)
C10	0.3725 (4)	−0.1082 (2)	0.12739 (7)	0.0416 (5)
C11	0.6914 (4)	−0.1913 (2)	0.07992 (8)	0.0549 (6)
H11A	0.6044	−0.2731	0.0651	0.066*
H11B	0.7751	−0.2310	0.1082	0.066*
C12	0.8524 (5)	−0.1263 (3)	0.04293 (9)	0.0690 (7)
H12A	0.7685	−0.0927	0.0143	0.103*
H12B	0.9611	−0.2020	0.0331	0.103*
H12C	0.9317	−0.0421	0.0574	0.103*
N1	0.2846 (4)	0.2472 (2)	0.03570 (6)	0.0609 (6)
N2	0.3108 (3)	0.1267 (2)	0.01436 (6)	0.0529 (5)
N3	0.3227 (4)	0.0230 (2)	−0.00996 (8)	0.0761 (7)
N4	0.0774 (3)	0.25006 (16)	0.14463 (5)	0.0399 (4)
O1	0.4886 (3)	0.46778 (16)	0.13778 (6)	0.0525 (4)
O2	0.3448 (3)	−0.23589 (14)	0.14310 (5)	0.0606 (4)
O3	0.5397 (3)	−0.07109 (14)	0.09559 (5)	0.0487 (4)
H1A	0.464 (4)	0.559 (3)	0.1427 (7)	0.059 (7)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0490 (11)	0.0291 (9)	0.0454 (10)	0.0003 (9)	0.0058 (9)	0.0018 (8)
C2	0.0520 (12)	0.0250 (9)	0.0485 (10)	0.0019 (9)	−0.0001 (10)	0.0054 (8)
C3	0.0533 (12)	0.0270 (9)	0.0538 (10)	0.0075 (9)	0.0017 (10)	0.0037 (9)
C4A	0.0418 (10)	0.0342 (9)	0.0410 (9)	0.0008 (9)	−0.0003 (9)	0.0004 (8)
C5	0.0437 (11)	0.0505 (12)	0.0514 (11)	0.0066 (10)	0.0042 (10)	0.0008 (9)
C6	0.0498 (13)	0.0658 (15)	0.0546 (11)	0.0001 (12)	0.0078 (11)	0.0027 (11)
C7	0.0607 (14)	0.0550 (14)	0.0549 (11)	−0.0106 (12)	0.0080 (12)	0.0120 (10)
C8	0.0601 (13)	0.0372 (10)	0.0495 (10)	−0.0056 (11)	0.0000 (11)	0.0062 (9)
C8A	0.0445 (11)	0.0330 (10)	0.0399 (9)	−0.0014 (9)	−0.0033 (9)	−0.0001 (8)
C9	0.0479 (11)	0.0257 (9)	0.0401 (9)	−0.0006 (8)	0.0000 (9)	−0.0003 (7)
C9A	0.0431 (10)	0.0277 (9)	0.0377 (9)	0.0003 (9)	0.0007 (9)	−0.0040 (8)
C10	0.0525 (12)	0.0288 (10)	0.0436 (10)	0.0004 (9)	0.0002 (10)	−0.0025 (8)
C11	0.0630 (15)	0.0410 (11)	0.0607 (12)	0.0074 (11)	0.0101 (12)	−0.0105 (10)
C12	0.0609 (15)	0.0678 (16)	0.0782 (15)	−0.0012 (13)	0.0157 (14)	−0.0095 (13)
N1	0.0961 (16)	0.0436 (10)	0.0430 (9)	0.0084 (12)	0.0007 (10)	0.0004 (8)
N2	0.0620 (13)	0.0513 (11)	0.0454 (9)	−0.0090 (9)	0.0077 (9)	0.0022 (9)
N3	0.0973 (19)	0.0649 (13)	0.0660 (12)	−0.0099 (14)	0.0049 (12)	−0.0215 (11)
N4	0.0456 (9)	0.0274 (8)	0.0466 (8)	0.0041 (8)	0.0032 (8)	0.0032 (7)
O1	0.0547 (9)	0.0273 (7)	0.0754 (9)	0.0029 (6)	−0.0061 (8)	−0.0032 (7)
O2	0.0778 (11)	0.0246 (7)	0.0793 (10)	0.0048 (8)	0.0217 (9)	0.0060 (7)
O3	0.0599 (9)	0.0304 (7)	0.0559 (7)	0.0041 (7)	0.0136 (7)	0.0003 (6)

Geometric parameters (Å, º)

C1—N1	1.487 (2)	C8—C8A	1.405 (3)
C1—C9A	1.494 (2)	C8—H8	0.9300
C1—C2	1.544 (2)	C8A—C9	1.441 (3)
C1—H1	0.9800	C9—C9A	1.383 (2)
C2—O1	1.414 (2)	C9—C10	1.445 (3)
C2—C3	1.537 (3)	C9A—N4	1.354 (2)
C2—H2	0.9800	C10—O2	1.216 (2)
C3—N4	1.469 (2)	C10—O3	1.341 (2)
C3—H3A	0.9700	C11—O3	1.447 (2)
C3—H3B	0.9700	C11—C12	1.486 (3)
C4A—N4	1.382 (2)	C11—H11A	0.9700
C4A—C5	1.387 (3)	C11—H11B	0.9700
C4A—C8A	1.413 (2)	C12—H12A	0.9600
C5—C6	1.375 (3)	C12—H12B	0.9600
C5—H5	0.9300	C12—H12C	0.9600
C6—C7	1.397 (3)	N1—N2	1.220 (2)
C6—H6	0.9300	N2—N3	1.129 (2)
C7—C8	1.375 (3)	O1—H1A	0.83 (2)
C7—H7	0.9300
N1—C1—C9A	112.23 (16)	C8A—C8—H8	120.8
N1—C1—C2	106.00 (15)	C8—C8A—C4A	118.36 (17)
C9A—C1—C2	102.57 (14)	C8—C8A—C9	134.32 (17)
N1—C1—H1	111.8	C4A—C8A—C9	107.31 (15)
C9A—C1—H1	111.8	C9A—C9—C8A	106.35 (16)
C2—C1—H1	111.8	C9A—C9—C10	127.71 (18)
O1—C2—C3	112.02 (15)	C8A—C9—C10	125.94 (16)
O1—C2—C1	106.78 (16)	N4—C9A—C9	109.28 (16)
C3—C2—C1	105.16 (16)	N4—C9A—C1	109.35 (15)
O1—C2—H2	110.9	C9—C9A—C1	141.30 (18)
C3—C2—H2	110.9	O2—C10—O3	123.11 (17)
C1—C2—H2	110.9	O2—C10—C9	123.97 (19)
N4—C3—C2	101.91 (15)	O3—C10—C9	112.92 (15)
N4—C3—H3A	111.4	O3—C11—C12	107.40 (18)
C2—C3—H3A	111.4	O3—C11—H11A	110.2
N4—C3—H3B	111.4	C12—C11—H11A	110.2
C2—C3—H3B	111.4	O3—C11—H11B	110.2
H3A—C3—H3B	109.3	C12—C11—H11B	110.2
N4—C4A—C5	130.79 (18)	H11A—C11—H11B	108.5
N4—C4A—C8A	106.36 (16)	C11—C12—H12A	109.5
C5—C4A—C8A	122.84 (18)	C11—C12—H12B	109.5
C6—C5—C4A	117.35 (19)	H12A—C12—H12B	109.5
C6—C5—H5	121.3	C11—C12—H12C	109.5
C4A—C5—H5	121.3	H12A—C12—H12C	109.5
C5—C6—C7	121.0 (2)	H12B—C12—H12C	109.5
C5—C6—H6	119.5	N2—N1—C1	117.84 (18)
C7—C6—H6	119.5	N3—N2—N1	172.0 (2)
C8—C7—C6	122.0 (2)	C9A—N4—C4A	110.69 (14)
C8—C7—H7	119.0	C9A—N4—C3	113.92 (15)
C6—C7—H7	119.0	C4A—N4—C3	135.38 (16)
C7—C8—C8A	118.5 (2)	C2—O1—H1A	104.6 (16)
C7—C8—H8	120.8	C10—O3—C11	116.95 (15)
N1—C1—C2—O1	−149.18 (16)	C10—C9—C9A—C1	3.7 (4)
C9A—C1—C2—O1	92.98 (18)	N1—C1—C9A—N4	−94.40 (18)
N1—C1—C2—C3	91.65 (18)	C2—C1—C9A—N4	18.93 (19)
C9A—C1—C2—C3	−26.20 (19)	N1—C1—C9A—C9	82.1 (3)
O1—C2—C3—N4	−91.76 (18)	C2—C1—C9A—C9	−164.6 (2)
C1—C2—C3—N4	23.86 (19)	C9A—C9—C10—O2	−177.7 (2)
N4—C4A—C5—C6	−179.6 (2)	C8A—C9—C10—O2	2.1 (3)
C8A—C4A—C5—C6	1.0 (3)	C9A—C9—C10—O3	1.8 (3)
C4A—C5—C6—C7	0.1 (3)	C8A—C9—C10—O3	−178.47 (17)
C5—C6—C7—C8	−0.9 (3)	C9A—C1—N1—N2	−68.4 (3)
C6—C7—C8—C8A	0.6 (3)	C2—C1—N1—N2	−179.64 (19)
C7—C8—C8A—C4A	0.4 (3)	C9—C9A—N4—C4A	−0.6 (2)
C7—C8—C8A—C9	179.6 (2)	C1—C9A—N4—C4A	177.10 (15)
N4—C4A—C8A—C8	179.18 (16)	C9—C9A—N4—C3	178.47 (17)
C5—C4A—C8A—C8	−1.2 (3)	C1—C9A—N4—C3	−3.9 (2)
N4—C4A—C8A—C9	−0.26 (19)	C5—C4A—N4—C9A	−179.04 (19)
C5—C4A—C8A—C9	179.33 (17)	C8A—C4A—N4—C9A	0.5 (2)
C8—C8A—C9—C9A	−179.4 (2)	C5—C4A—N4—C3	2.2 (4)
C4A—C8A—C9—C9A	−0.1 (2)	C8A—C4A—N4—C3	−178.2 (2)
C8—C8A—C9—C10	0.8 (3)	C2—C3—N4—C9A	−13.0 (2)
C4A—C8A—C9—C10	−179.87 (19)	C2—C3—N4—C4A	165.66 (19)
C8A—C9—C9A—N4	0.4 (2)	O2—C10—O3—C11	0.1 (3)
C10—C9—C9A—N4	−179.83 (18)	C9—C10—O3—C11	−179.40 (17)
C8A—C9—C9A—C1	−176.1 (2)	C12—C11—O3—C10	176.76 (17)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1A···O2^i	0.83 (2)	1.94 (2)	2.7553 (19)	166 (2)

Symmetry code: (i) x, y+1, z.