(S)-2-(1-Benzyl-5-bromo-1H-indol-3-yl)-2-hydr­oxy-N-methyl­acetamide

The title compound, C₁₈H₁₇BrN₂O₂, is a chiral indole derivative. The crystal structure shows both intra- and inter­molecular hydrogen-bonding inter­actions.

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.029
• wR factor = 0.063
• Data-to-parameter ratio = 16.2

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT220_ALERT_2_C Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       2.54 Ratio

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               3482
           Count of symmetry unique reflns         2026
           Completeness (_total/calc)            171.87%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured      1456
           Fraction of Friedel pairs measured     0.719
           Are heavy atom types Z>Si present        yes
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C16    = .          S
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          1

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

   1 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
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

Derivatives of indole have received much attention because of their widespread applications in materials science, agrichemicals, and pharmaceuticals (Ramirez & Garcia-Rubio, 2003). Their preparation and functionalization continues to be a fascinating subject in organic synthesis due to the frequent appearance of indoles in biologically interesting compounds (Bandini et al., 2005). The title compound, an example of a derivatized indole core, is shown in Figure 1. In the crystal, C—H···O hydrogen bonds, (Table 1) link the molecules in rows along the c axis (Fig. 2)

Related literature

For related literature, see: Bandini et al. (2005); Ramirez & Garcia-Rubio (2003); Yuan et al. (2004).

S2. Experimental

The title compound was synthesized according to procedure of Yuan et al., 2004. Crystals appropriate for data collection were obtained by slow evaporation of a CH₃COCH₃/C₆H₆ (100:1, v/v) solution at 283 K.

S3. Refinement

All H atoms were initially located in a difference Fourier map. The methyl H atoms were then constrained to an ideal geometry with C—H distances of 0.98 Å and U_iso(H) = 1.5U_eq(C), but each group was allowed to rotate freely about its C—C bond. All other H atoms bonded to carbon were placed in geometrically idealized positions and constrained to ride on their parent atoms with C—H distances in the range 0.95–1.00 Å and U_iso(H) = 1.2U_eq(C). The O—H and N—H H atom coordinates were allowed to refine but the thermal parameters were fixed.

Computing details

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Sheldrick, 2001b) and PLATON (Spek, 2003); software used to prepare material for publication: SHELXTL.

Figures

	Fig. 1. The structure of (I), showing the atom-labelling scheme and thermal ellipsoids at the 50% probability level.
	Fig. 2. The molecular packing of (I) viewed along the c axis. Hydrogen bonds are drawn as dashed lines.

(S)-2-(1-Benzyl-5-bromo-1H-indol-3-yl)-2-hydroxy-N- methylacetamide

Crystal data

C18H17BrN2O2	F(000) = 380
Mr = 373.25	Dx = 1.558 Mg m^−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 2442 reflections
a = 4.5759 (6) Å	θ = 0.0–0.0°
b = 9.4134 (11) Å	µ = 2.60 mm^−1
c = 18.540 (2) Å	T = 296 K
β = 95.049 (2)°	Block, colorless
V = 795.51 (17) Å^3	0.20 × 0.20 × 0.10 mm
Z = 2

Data collection

Bruker SMART CCD area-detector diffractometer	3482 independent reflections
Radiation source: fine-focus sealed tube	2936 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.021
φ and ω scans	θmax = 28.0°, θmin = 2.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 2001a)	h = −6→5
Tmin = 0.625, Tmax = 0.781	k = −11→12
5321 measured reflections	l = −22→24

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)] = 0.029	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.063	w = 1/[σ^2(Fo^2)] where P = (Fo^2 + 2Fc^2)/3
S = 0.95	(Δ/σ)max = 0.002
3482 reflections	Δρmax = 0.40 e Å^−3
215 parameters	Δρmin = −0.32 e Å^−3
1 restraint	Absolute structure: Flack (1983), 1456 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.015 (7)

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
Br1	1.14694 (7)	−0.31988 (3)	0.737099 (16)	0.06370 (11)
C1	0.6534 (6)	0.0039 (3)	0.81575 (12)	0.0391 (6)
H1A	0.5425	0.0180	0.8548	0.047*
C2	0.8019 (6)	−0.1216 (3)	0.80734 (13)	0.0433 (6)
H2	0.7932	−0.1936	0.8414	0.052*
C3	0.9654 (6)	−0.1411 (3)	0.74796 (13)	0.0391 (5)
C4	0.9924 (5)	−0.0383 (2)	0.69649 (12)	0.0341 (5)
H4	1.1062	−0.0534	0.6580	0.041*
C5	0.8429 (5)	0.0900 (2)	0.70371 (11)	0.0298 (5)
C6	0.6757 (5)	0.1082 (3)	0.76376 (12)	0.0318 (5)
C7	0.8163 (5)	0.2179 (2)	0.66256 (11)	0.0317 (5)
C8	0.6355 (5)	0.3059 (3)	0.69713 (12)	0.0357 (5)
H8	0.5795	0.3967	0.6817	0.043*
C9	0.3612 (5)	0.3018 (3)	0.81004 (12)	0.0403 (5)
H9A	0.2210	0.2306	0.8225	0.048*
H9B	0.2518	0.3806	0.7874	0.048*
C10	0.5304 (5)	0.3531 (3)	0.87805 (12)	0.0362 (5)
C11	0.7243 (6)	0.4648 (3)	0.87613 (14)	0.0482 (6)
H11	0.7512	0.5078	0.8320	0.058*
C12	0.8776 (7)	0.5135 (4)	0.93757 (19)	0.0689 (9)
H12	1.0081	0.5887	0.9350	0.083*
C13	0.8399 (8)	0.4520 (5)	1.00341 (18)	0.0757 (11)
H13	0.9437	0.4858	1.0453	0.091*
C14	0.6496 (9)	0.3411 (4)	1.00709 (15)	0.0733 (11)
H14	0.6246	0.2985	1.0514	0.088*
C15	0.4936 (7)	0.2922 (3)	0.94434 (13)	0.0545 (7)
H15	0.3624	0.2173	0.9470	0.065*
C16	0.9457 (5)	0.2509 (2)	0.59302 (12)	0.0352 (5)
H16	1.1449	0.2120	0.5951	0.042*
C17	0.7595 (5)	0.1810 (3)	0.53065 (10)	0.0338 (4)
C18	0.3941 (7)	0.2177 (3)	0.42835 (13)	0.0538 (8)
H18A	0.5083	0.1786	0.3921	0.081*
H18B	0.2787	0.2955	0.4081	0.081*
H18C	0.2667	0.1457	0.4446	0.081*
H1	1.088 (8)	0.418 (4)	0.5528 (18)	0.081*
H2A	0.572 (7)	0.358 (3)	0.4998 (16)	0.065*
N1	0.5491 (5)	0.2407 (2)	0.75786 (10)	0.0357 (5)
N2	0.5881 (5)	0.2677 (2)	0.48896 (11)	0.0400 (5)
O1	0.9600 (4)	0.40069 (17)	0.58655 (9)	0.0473 (4)
O2	0.7673 (4)	0.05083 (18)	0.52216 (9)	0.0470 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Br1	0.0778 (2)	0.03513 (14)	0.0805 (2)	0.01527 (16)	0.02007 (15)	0.01439 (16)
C1	0.0485 (15)	0.0387 (14)	0.0309 (11)	−0.0056 (11)	0.0081 (11)	0.0018 (10)
C2	0.0576 (16)	0.0373 (14)	0.0348 (12)	−0.0030 (12)	0.0021 (11)	0.0105 (10)
C3	0.0440 (14)	0.0296 (12)	0.0428 (13)	0.0029 (10)	−0.0012 (11)	0.0021 (10)
C4	0.0362 (12)	0.0327 (12)	0.0333 (11)	−0.0003 (9)	0.0023 (10)	−0.0031 (9)
C5	0.0320 (12)	0.0310 (12)	0.0260 (11)	−0.0047 (9)	0.0010 (9)	−0.0029 (9)
C6	0.0364 (14)	0.0324 (13)	0.0262 (11)	−0.0044 (10)	0.0001 (10)	−0.0015 (10)
C7	0.0372 (12)	0.0282 (13)	0.0295 (11)	−0.0015 (8)	0.0017 (9)	−0.0013 (8)
C8	0.0437 (14)	0.0301 (12)	0.0329 (12)	0.0022 (10)	0.0010 (10)	−0.0012 (10)
C9	0.0381 (13)	0.0436 (14)	0.0400 (13)	0.0040 (11)	0.0082 (10)	−0.0024 (11)
C10	0.0405 (13)	0.0346 (13)	0.0347 (12)	0.0062 (10)	0.0096 (10)	−0.0053 (10)
C11	0.0534 (17)	0.0466 (16)	0.0447 (14)	−0.0031 (13)	0.0046 (13)	−0.0055 (12)
C12	0.0581 (19)	0.065 (2)	0.081 (2)	−0.0043 (16)	−0.0046 (17)	−0.0260 (18)
C13	0.078 (2)	0.086 (3)	0.058 (2)	0.036 (2)	−0.0207 (18)	−0.0336 (19)
C14	0.113 (3)	0.077 (3)	0.0312 (15)	0.044 (2)	0.0104 (17)	0.0035 (15)
C15	0.075 (2)	0.0504 (17)	0.0411 (15)	0.0064 (16)	0.0212 (14)	0.0033 (13)
C16	0.0404 (13)	0.0287 (12)	0.0371 (12)	−0.0001 (10)	0.0070 (10)	0.0034 (9)
C17	0.0456 (11)	0.0293 (10)	0.0283 (9)	0.0020 (13)	0.0135 (9)	0.0016 (12)
C18	0.0660 (17)	0.058 (2)	0.0360 (12)	−0.0011 (13)	−0.0042 (12)	0.0037 (11)
N1	0.0426 (12)	0.0356 (11)	0.0297 (10)	0.0011 (10)	0.0072 (9)	−0.0021 (8)
N2	0.0551 (13)	0.0321 (11)	0.0327 (10)	0.0015 (10)	0.0028 (9)	0.0017 (9)
O1	0.0682 (12)	0.0299 (10)	0.0453 (9)	−0.0101 (9)	0.0148 (9)	0.0029 (7)
O2	0.0721 (13)	0.0283 (9)	0.0405 (9)	0.0045 (9)	0.0045 (9)	−0.0032 (7)

Geometric parameters (Å, º)

Br1—C3	1.895 (2)	C10—C15	1.380 (3)
C1—C2	1.378 (4)	C11—C12	1.363 (4)
C1—C6	1.386 (3)	C11—H11	0.9300
C1—H1A	0.9300	C12—C13	1.376 (5)
C2—C3	1.397 (4)	C12—H12	0.9300
C2—H2	0.9300	C13—C14	1.365 (5)
C3—C4	1.372 (3)	C13—H13	0.9300
C4—C5	1.400 (3)	C14—C15	1.389 (5)
C4—H4	0.9300	C14—H14	0.9300
C5—C6	1.416 (3)	C15—H15	0.9300
C5—C7	1.425 (3)	C16—O1	1.418 (3)
C6—N1	1.375 (3)	C16—C17	1.524 (3)
C7—C8	1.369 (3)	C16—H16	0.9800
C7—C16	1.498 (3)	C17—O2	1.236 (4)
C8—N1	1.371 (3)	C17—N2	1.331 (3)
C8—H8	0.9300	C18—N2	1.448 (3)
C9—N1	1.467 (3)	C18—H18A	0.9600
C9—C10	1.500 (3)	C18—H18B	0.9600
C9—H9A	0.9700	C18—H18C	0.9600
C9—H9B	0.9700	N2—H2A	0.87 (3)
C10—C11	1.378 (4)	O1—H1	0.91 (4)
C2—C1—C6	117.5 (2)	C10—C11—H11	119.3
C2—C1—H1A	121.3	C11—C12—C13	120.3 (3)
C6—C1—H1A	121.3	C11—C12—H12	119.9
C1—C2—C3	120.4 (2)	C13—C12—H12	119.9
C1—C2—H2	119.8	C14—C13—C12	119.8 (3)
C3—C2—H2	119.8	C14—C13—H13	120.1
C4—C3—C2	122.9 (2)	C12—C13—H13	120.1
C4—C3—Br1	119.02 (18)	C13—C14—C15	119.6 (3)
C2—C3—Br1	118.10 (18)	C13—C14—H14	120.2
C3—C4—C5	117.9 (2)	C15—C14—H14	120.2
C3—C4—H4	121.1	C10—C15—C14	121.0 (3)
C5—C4—H4	121.1	C10—C15—H15	119.5
C4—C5—C6	118.8 (2)	C14—C15—H15	119.5
C4—C5—C7	134.2 (2)	O1—C16—C7	107.67 (18)
C6—C5—C7	107.0 (2)	O1—C16—C17	113.1 (2)
N1—C6—C1	129.9 (2)	C7—C16—C17	109.08 (18)
N1—C6—C5	107.5 (2)	O1—C16—H16	109.0
C1—C6—C5	122.6 (2)	C7—C16—H16	109.0
C8—C7—C5	106.69 (19)	C17—C16—H16	109.0
C8—C7—C16	125.3 (2)	O2—C17—N2	123.8 (2)
C5—C7—C16	127.91 (19)	O2—C17—C16	120.3 (2)
C7—C8—N1	110.1 (2)	N2—C17—C16	116.0 (2)
C7—C8—H8	125.0	N2—C18—H18A	109.5
N1—C8—H8	125.0	N2—C18—H18B	109.5
N1—C9—C10	113.0 (2)	H18A—C18—H18B	109.5
N1—C9—H9A	109.0	N2—C18—H18C	109.5
C10—C9—H9A	109.0	H18A—C18—H18C	109.5
N1—C9—H9B	109.0	H18B—C18—H18C	109.5
C10—C9—H9B	109.0	C8—N1—C6	108.7 (2)
H9A—C9—H9B	107.8	C8—N1—C9	126.5 (2)
C11—C10—C15	118.0 (2)	C6—N1—C9	124.8 (2)
C11—C10—C9	120.7 (2)	C17—N2—C18	122.7 (2)
C15—C10—C9	121.3 (2)	C17—N2—H2A	121 (2)
C12—C11—C10	121.3 (3)	C18—N2—H2A	116 (2)
C12—C11—H11	119.3	C16—O1—H1	106 (2)
C6—C1—C2—C3	−0.5 (4)	C11—C12—C13—C14	0.4 (5)
C1—C2—C3—C4	1.3 (4)	C12—C13—C14—C15	−0.6 (5)
C1—C2—C3—Br1	−176.7 (2)	C11—C10—C15—C14	−0.7 (4)
C2—C3—C4—C5	−1.4 (4)	C9—C10—C15—C14	−179.5 (2)
Br1—C3—C4—C5	176.59 (17)	C13—C14—C15—C10	0.7 (4)
C3—C4—C5—C6	0.8 (3)	C8—C7—C16—O1	25.1 (3)
C3—C4—C5—C7	−179.7 (2)	C5—C7—C16—O1	−158.0 (2)
C2—C1—C6—N1	178.8 (2)	C8—C7—C16—C17	−97.9 (3)
C2—C1—C6—C5	0.0 (4)	C5—C7—C16—C17	78.9 (3)
C4—C5—C6—N1	−179.2 (2)	O1—C16—C17—O2	167.5 (2)
C7—C5—C6—N1	1.2 (2)	C7—C16—C17—O2	−72.7 (3)
C4—C5—C6—C1	−0.1 (3)	O1—C16—C17—N2	−14.3 (3)
C7—C5—C6—C1	−179.7 (2)	C7—C16—C17—N2	105.5 (2)
C4—C5—C7—C8	179.5 (2)	C7—C8—N1—C6	0.4 (3)
C6—C5—C7—C8	−1.0 (3)	C7—C8—N1—C9	178.4 (2)
C4—C5—C7—C16	2.1 (4)	C1—C6—N1—C8	−180.0 (2)
C6—C5—C7—C16	−178.3 (2)	C5—C6—N1—C8	−1.0 (2)
C5—C7—C8—N1	0.4 (3)	C1—C6—N1—C9	1.9 (4)
C16—C7—C8—N1	177.8 (2)	C5—C6—N1—C9	−179.1 (2)
N1—C9—C10—C11	65.1 (3)	C10—C9—N1—C8	−101.6 (3)
N1—C9—C10—C15	−116.1 (3)	C10—C9—N1—C6	76.2 (3)
C15—C10—C11—C12	0.5 (4)	O2—C17—N2—C18	−0.7 (3)
C9—C10—C11—C12	179.4 (3)	C16—C17—N2—C18	−178.8 (2)
C10—C11—C12—C13	−0.3 (5)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···O1	0.87 (3)	2.32 (3)	2.682 (3)	105 (2)
C18—H18C···O1^i	0.96	2.57	3.395 (3)	144
N2—H2A···O2^ii	0.87 (3)	2.40 (3)	3.119 (3)	139 (3)
O1—H1···O2^iii	0.91 (4)	2.02 (4)	2.839 (2)	149 (3)

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