3-[(3,4,5-Tribromo-1H-pyrrol-2-ylcarbon­yl)amino]propanoic acid

The title compound, C₈H₇Br₃N₂O₃, was synthesized by condensation of β-alanine methyl ester with 3,4,5-tribromo-2-trichloro­acetyl­pyrrole at room temperature, followed by saponification and acidification. In the crystal structure, inter­molecular N—H...O hydrogen bonds and weak O—H...Br hydrogen-bond inter­actions link the mol­ecules into extended ribbons parallel to the c axis.

Key indicators

• Single-crystal X-ray study
• T = 273 K
• Mean [sigma](C-C) = 0.007 Å
• R factor = 0.037
• wR factor = 0.111
• Data-to-parameter ratio = 15.9

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT415_ALERT_2_B Short Inter D-H..H-X       H3     ..  H7B     ..       1.97 Ang.

Alert level C
ABSTM02_ALERT_3_C  The ratio of expected to reported Tmax/Tmin(RR) is > 1.10
            Tmin and Tmax reported:      0.050     0.072
            Tmin and Tmax expected:      0.047     0.076
            RR =      1.130
            Please check that your absorption correction is appropriate.
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low .......       0.97
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .......          ?
PLAT341_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          7

Alert level G
ABSTM02_ALERT_3_G  When printed, the submitted absorption T values will be
            replaced by the scaled T values. Since the ratio of scaled T's
            is identical to the ratio of reported T values, the scaling
            does not imply a change to the absorption corrections used in
            the study.
            Ratio of Tmax expected/reported      1.058
            Tmax scaled      0.076 Tmin scaled      0.053

   0 ALERT level A = In general: serious problem
   1 ALERT level B = Potentially serious problem
   4 ALERT level C = Check and explain
   1 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
   4 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 (Bruker,1999); cell refinement: SAINT-Plus (Bruker, 1999); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker,1997); software used to prepare material for publication: SHELXTL.

3-[(3,4,5-Tribromo-1H-pyrrol-2-ylcarbonyl)amino]propanoic acid

Crystal data

C8H7Br3N2O3	F(000) = 396
Mr = 418.89	Dx = 2.278 Mg m^−3
Triclinic, P1	Melting point: 481 K
a = 7.0199 (10) Å	Mo Kα radiation, λ = 0.71073 Å
b = 8.0368 (12) Å	Cell parameters from 2129 reflections
c = 11.5897 (16) Å	θ = 2.6–25.9°
α = 97.019 (2)°	µ = 9.90 mm^−1
β = 103.741 (2)°	T = 273 K
γ = 102.156 (2)°	Block, colorless
V = 610.61 (15) Å^3	0.34 × 0.29 × 0.26 mm
Z = 2

Data collection

Bruker SMART 1K CCD area-detector diffractometer	2328 independent reflections
Radiation source: fine-focus sealed tube	1837 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.025
φ and ω scans	θmax = 26.0°, θmin = 2.6°
Absorption correction: multi-scan (SADABS; Sheldrick,1996)	h = −8→8
Tmin = 0.050, Tmax = 0.072	k = −9→9
4506 measured reflections	l = −14→14

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.037	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.111	H-atom parameters constrained
S = 1.05	w = 1/[σ^2(Fo^2) + (0.0605P)^2 + 0.8415P] where P = (Fo^2 + 2Fc^2)/3
2328 reflections	(Δ/σ)max = 0.001
146 parameters	Δρmax = 0.80 e Å^−3
0 restraints	Δρmin = −0.81 e Å^−3

Special details

Experimental. ¹H NMR (DMSO₆, 300 Hz): δ 12.61 (brs, 1H), 12.22 (brs, 1H), 8.13 (t, 1H), 3.49–3.35 (m, 2H), 2.46 (t, 2H); IR (KBr): 3401, 2929, 1698, 1638, 1551, 1511, 1426, 1243, 778; Analysis calculated for C₈H₇Br₃N₂O₃: C 22.94, H 1.68, N 6.69%; found C 22.85, H 1.74, N 6.87.%

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	0.18695 (9)	0.14910 (9)	0.92476 (6)	0.0529 (2)
Br2	0.37542 (9)	0.08757 (8)	1.22695 (5)	0.0484 (2)
Br3	0.90944 (9)	0.29884 (10)	1.32263 (5)	0.0570 (2)
N1	0.7846 (6)	0.3519 (5)	1.0826 (4)	0.0338 (10)
H1	0.9052	0.4082	1.0864	0.041*
C3	0.4575 (7)	0.2267 (6)	1.0165 (4)	0.0292 (10)
C4	0.6208 (7)	0.3218 (6)	0.9845 (4)	0.0314 (10)
C1	0.7286 (8)	0.2799 (7)	1.1724 (4)	0.0364 (12)
C2	0.5276 (7)	0.2024 (6)	1.1357 (5)	0.0333 (11)
N2	0.4886 (6)	0.3699 (5)	0.7844 (4)	0.0349 (10)
H2	0.3707	0.3282	0.7932	0.042*
O1	0.8225 (6)	0.4464 (6)	0.8691 (4)	0.0533 (11)
C5	0.6516 (7)	0.3838 (6)	0.8758 (4)	0.0325 (11)
O3	0.2325 (6)	0.0105 (5)	0.4633 (4)	0.0482 (10)
H3	0.3376	0.0060	0.4452	0.072*
O2	0.1316 (6)	0.1865 (5)	0.5846 (4)	0.0501 (10)
C8	0.2643 (7)	0.1510 (7)	0.5417 (4)	0.0339 (11)
C6	0.5028 (8)	0.4224 (7)	0.6713 (5)	0.0388 (12)
H6A	0.6349	0.4996	0.6827	0.047*
H6B	0.4013	0.4854	0.6459	0.047*
C7	0.4722 (8)	0.2676 (7)	0.5728 (5)	0.0382 (12)
H7A	0.4960	0.3088	0.5009	0.046*
H7B	0.5707	0.2023	0.5996	0.046*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Br1	0.0356 (3)	0.0641 (4)	0.0475 (4)	−0.0056 (3)	0.0067 (3)	0.0071 (3)
Br2	0.0557 (4)	0.0481 (4)	0.0446 (3)	0.0027 (3)	0.0252 (3)	0.0146 (2)
Br3	0.0458 (4)	0.0883 (5)	0.0368 (3)	0.0174 (3)	0.0034 (3)	0.0250 (3)
N1	0.026 (2)	0.046 (3)	0.027 (2)	0.0028 (19)	0.0075 (17)	0.0099 (18)
C3	0.025 (2)	0.030 (2)	0.031 (2)	0.0031 (19)	0.0071 (19)	0.0047 (19)
C4	0.034 (3)	0.032 (3)	0.029 (2)	0.011 (2)	0.011 (2)	0.003 (2)
C1	0.041 (3)	0.043 (3)	0.027 (2)	0.014 (2)	0.009 (2)	0.010 (2)
C2	0.035 (3)	0.031 (3)	0.035 (3)	0.006 (2)	0.013 (2)	0.005 (2)
N2	0.029 (2)	0.040 (2)	0.031 (2)	0.0007 (18)	0.0051 (17)	0.0087 (18)
O1	0.032 (2)	0.083 (3)	0.038 (2)	−0.006 (2)	0.0065 (17)	0.024 (2)
C5	0.030 (3)	0.032 (3)	0.028 (2)	0.002 (2)	0.003 (2)	0.0013 (19)
O3	0.045 (2)	0.045 (2)	0.051 (2)	0.0030 (18)	0.0205 (19)	−0.0063 (18)
O2	0.036 (2)	0.059 (3)	0.047 (2)	0.0061 (19)	0.0110 (18)	−0.0091 (19)
C8	0.035 (3)	0.041 (3)	0.026 (2)	0.011 (2)	0.005 (2)	0.007 (2)
C6	0.038 (3)	0.040 (3)	0.033 (3)	0.002 (2)	0.005 (2)	0.012 (2)
C7	0.037 (3)	0.044 (3)	0.034 (3)	0.005 (2)	0.014 (2)	0.010 (2)

Geometric parameters (Å, º)

Br1—C3	1.873 (5)	N2—H2	0.8600
Br2—C2	1.863 (5)	O1—C5	1.224 (6)
Br3—C1	1.863 (5)	O3—C8	1.303 (6)
N1—C1	1.348 (6)	O3—H3	0.8200
N1—C4	1.366 (6)	O2—C8	1.223 (6)
N1—H1	0.8600	C8—C7	1.493 (7)
C3—C4	1.392 (7)	C6—C7	1.523 (8)
C3—C2	1.404 (7)	C6—H6A	0.9700
C4—C5	1.456 (7)	C6—H6B	0.9700
C1—C2	1.357 (7)	C7—H7A	0.9700
N2—C5	1.336 (6)	C7—H7B	0.9700
N2—C6	1.444 (6)
C1—N1—C4	109.7 (4)	O1—C5—C4	120.5 (4)
C1—N1—H1	125.1	N2—C5—C4	118.1 (4)
C4—N1—H1	125.1	C8—O3—H3	109.5
C4—C3—C2	107.9 (4)	O2—C8—O3	122.2 (5)
C4—C3—Br1	128.1 (4)	O2—C8—C7	122.4 (5)
C2—C3—Br1	123.9 (4)	O3—C8—C7	115.3 (4)
N1—C4—C3	106.3 (4)	N2—C6—C7	111.8 (4)
N1—C4—C5	118.2 (4)	N2—C6—H6A	109.3
C3—C4—C5	135.4 (4)	C7—C6—H6A	109.3
N1—C1—C2	109.4 (4)	N2—C6—H6B	109.3
N1—C1—Br3	122.4 (4)	C7—C6—H6B	109.3
C2—C1—Br3	128.2 (4)	H6A—C6—H6B	107.9
C1—C2—C3	106.6 (4)	C8—C7—C6	112.4 (4)
C1—C2—Br2	126.4 (4)	C8—C7—H7A	109.1
C3—C2—Br2	127.0 (4)	C6—C7—H7A	109.1
C5—N2—C6	122.5 (4)	C8—C7—H7B	109.1
C5—N2—H2	118.7	C6—C7—H7B	109.1
C6—N2—H2	118.7	H7A—C7—H7B	107.9
O1—C5—N2	121.4 (5)
C1—N1—C4—C3	−0.1 (6)	Br1—C3—C2—C1	−178.3 (4)
C1—N1—C4—C5	−177.7 (4)	C4—C3—C2—Br2	178.9 (4)
C2—C3—C4—N1	0.5 (5)	Br1—C3—C2—Br2	1.3 (7)
Br1—C3—C4—N1	178.0 (4)	C6—N2—C5—O1	1.9 (8)
C2—C3—C4—C5	177.5 (5)	C6—N2—C5—C4	−178.0 (5)
Br1—C3—C4—C5	−5.0 (9)	N1—C4—C5—O1	6.7 (7)
C4—N1—C1—C2	−0.4 (6)	C3—C4—C5—O1	−170.0 (6)
C4—N1—C1—Br3	−178.3 (4)	N1—C4—C5—N2	−173.4 (4)
N1—C1—C2—C3	0.7 (6)	C3—C4—C5—N2	9.9 (9)
Br3—C1—C2—C3	178.4 (4)	C5—N2—C6—C7	102.4 (5)
N1—C1—C2—Br2	−178.9 (4)	O2—C8—C7—C6	5.7 (7)
Br3—C1—C2—Br2	−1.2 (8)	O3—C8—C7—C6	−175.9 (4)
C4—C3—C2—C1	−0.7 (6)	N2—C6—C7—C8	64.4 (6)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···Br2^i	0.82	2.75	3.217 (4)	118
N1—H1···O1^ii	0.86	1.93	2.777 (5)	168

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