2-Acetyl-3-amino-1-benzo­furan

The title compound, C₁₀H₉NO₂, displays the characteristic features of a benzo­furan derivative. The molecular structure is nearly planar with an intramolecular N—H...O hydrogen bond involving the amino group and the acetyl carbonyl O atom. In the crystal structure, there are intermolecular N—H...O and C—H...O interactions, which help to stabilize the structure.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.035
• wR factor = 0.103
• Data-to-parameter ratio = 13.1

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT063_ALERT_3_C Crystal Probably too Large for Beam Size .......       0.65 mm

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   1 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
   0 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

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Computing details

Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA; data reduction: X-RED32 (Stoe & Cie, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPIII (Burnett & Johnson, 1996); software used to prepare material for publication: WinGX (Farrugia, 1999).

2-Acetyl-3-amino-1-benzofuran

Crystal data

C10H9NO2	F(000) = 368
Mr = 175.18	Dx = 1.367 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 12005 reflections
a = 5.1800 (4) Å	θ = 2.1–27.6°
b = 16.5600 (14) Å	µ = 0.10 mm^−1
c = 10.2271 (8) Å	T = 293 K
β = 104.020 (6)°	Prism, colourless
V = 851.16 (12) Å^3	0.65 × 0.42 × 0.35 mm
Z = 4

Data collection

Stoe IPDS-2 diffractometer	1547 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.071
Graphite monochromator	θmax = 27.4°, θmin = 2.4°
Detector resolution: 6.67 pixels mm^-1	h = −6→6
ω scans	k = −21→21
13507 measured reflections	l = −13→13
1932 independent 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 atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.103	w = 1/[σ^2(Fo^2) + (0.0605P)^2 + 0.0487P] where P = (Fo^2 + 2Fc^2)/3
S = 1.07	(Δ/σ)max < 0.001
1932 reflections	Δρmax = 0.18 e Å^−3
147 parameters	Δρmin = −0.12 e Å^−3
0 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.117 (14)

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
H1A	0.009 (4)	0.5391 (14)	0.192 (2)	0.115 (7)*
H1B	0.167 (4)	0.6181 (12)	0.201 (2)	0.099 (6)*
H1C	−0.097 (5)	0.6120 (13)	0.095 (3)	0.118 (7)*
H6	−0.033 (3)	0.6899 (8)	0.8119 (14)	0.058 (4)*
H7	0.330 (3)	0.6268 (9)	0.9688 (16)	0.065 (4)*
H8	0.624 (3)	0.5354 (9)	0.8902 (16)	0.068 (4)*
H9	0.565 (3)	0.5117 (9)	0.6559 (15)	0.072 (4)*
C1	−0.0132 (3)	0.60000 (11)	0.18198 (14)	0.0647 (4)
C2	−0.1569 (2)	0.63751 (7)	0.27700 (11)	0.0484 (3)
C3	−0.0530 (2)	0.62745 (7)	0.41757 (11)	0.0476 (3)
C4	−0.1306 (2)	0.66479 (7)	0.52237 (11)	0.0467 (3)
C5	0.0559 (2)	0.63876 (7)	0.64360 (11)	0.0463 (3)
C6	0.0911 (3)	0.65401 (8)	0.78164 (12)	0.0526 (3)
C7	0.2998 (3)	0.61683 (8)	0.87015 (12)	0.0573 (3)
C8	0.4717 (3)	0.56487 (9)	0.82422 (13)	0.0598 (3)
C9	0.4402 (3)	0.54852 (9)	0.68901 (13)	0.0567 (3)
C10	0.2308 (2)	0.58662 (7)	0.60144 (11)	0.0477 (3)
N1	−0.3354 (2)	0.71555 (7)	0.51113 (10)	0.0597 (3)
H1D	−0.4328	0.7276	0.4328	0.072*
H1E	−0.3698	0.7362	0.5822	0.072*
O1	−0.35967 (18)	0.67927 (6)	0.23604 (8)	0.0580 (3)
O2	0.16947 (16)	0.57834 (5)	0.46509 (8)	0.0521 (3)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0625 (8)	0.0893 (11)	0.0420 (7)	0.0007 (8)	0.0118 (6)	−0.0064 (7)
C2	0.0499 (6)	0.0525 (6)	0.0414 (6)	−0.0079 (5)	0.0085 (5)	−0.0001 (5)
C3	0.0510 (6)	0.0495 (6)	0.0414 (6)	0.0002 (5)	0.0091 (5)	−0.0009 (4)
C4	0.0522 (6)	0.0450 (5)	0.0427 (6)	−0.0026 (5)	0.0108 (5)	−0.0014 (4)
C5	0.0521 (6)	0.0462 (6)	0.0403 (6)	−0.0043 (5)	0.0106 (5)	−0.0012 (4)
C6	0.0619 (7)	0.0539 (6)	0.0426 (6)	−0.0029 (6)	0.0137 (5)	−0.0039 (5)
C7	0.0658 (8)	0.0647 (8)	0.0397 (6)	−0.0071 (6)	0.0091 (5)	−0.0021 (5)
C8	0.0572 (7)	0.0711 (8)	0.0466 (7)	0.0002 (6)	0.0039 (5)	0.0037 (6)
C9	0.0524 (7)	0.0675 (8)	0.0487 (7)	0.0048 (6)	0.0091 (5)	0.0003 (5)
C10	0.0506 (6)	0.0524 (6)	0.0391 (6)	−0.0028 (5)	0.0091 (5)	−0.0017 (4)
N1	0.0680 (7)	0.0632 (6)	0.0460 (6)	0.0161 (5)	0.0105 (5)	−0.0019 (4)
O1	0.0580 (5)	0.0665 (5)	0.0472 (5)	0.0022 (4)	0.0085 (4)	0.0077 (4)
O2	0.0550 (5)	0.0603 (5)	0.0399 (4)	0.0069 (4)	0.0094 (3)	−0.0031 (3)

Geometric parameters (Å, º)

C1—C2	1.4948 (18)	C6—C7	1.3761 (19)
C1—H1A	1.02 (2)	C6—H6	0.980 (14)
C1—H1B	0.95 (2)	C7—C8	1.399 (2)
C1—H1C	0.91 (2)	C7—H7	0.996 (16)
C2—O1	1.2425 (15)	C8—C9	1.3794 (18)
C2—C3	1.4174 (16)	C8—H8	1.028 (16)
C3—C4	1.3789 (15)	C9—C10	1.3807 (18)
C3—O2	1.3980 (14)	C9—H9	1.004 (16)
C4—N1	1.3363 (16)	C10—O2	1.3601 (14)
C4—C5	1.4411 (16)	N1—H1D	0.8600
C5—C10	1.3931 (16)	N1—H1E	0.8600
C5—C6	1.4020 (16)
C2—C1—H1A	114.1 (13)	C7—C6—H6	122.4 (8)
C2—C1—H1B	110.8 (12)	C5—C6—H6	119.5 (8)
H1A—C1—H1B	102.0 (18)	C6—C7—C8	121.14 (12)
C2—C1—H1C	110.4 (15)	C6—C7—H7	119.9 (9)
H1A—C1—H1C	109.4 (19)	C8—C7—H7	118.9 (9)
H1B—C1—H1C	109.8 (18)	C9—C8—C7	121.82 (12)
O1—C2—C3	119.31 (11)	C9—C8—H8	116.7 (9)
O1—C2—C1	121.70 (11)	C7—C8—H8	121.4 (9)
C3—C2—C1	118.96 (12)	C8—C9—C10	116.35 (12)
C4—C3—O2	111.20 (10)	C8—C9—H9	121.9 (9)
C4—C3—C2	128.69 (11)	C10—C9—H9	121.8 (9)
O2—C3—C2	119.95 (10)	O2—C10—C9	124.79 (11)
N1—C4—C3	126.16 (11)	O2—C10—C5	111.84 (10)
N1—C4—C5	127.96 (10)	C9—C10—C5	123.37 (11)
C3—C4—C5	105.88 (10)	C4—N1—H1D	120.0
C10—C5—C6	119.20 (11)	C4—N1—H1E	120.0
C10—C5—C4	105.66 (10)	H1D—N1—H1E	120.0
C6—C5—C4	135.14 (11)	C10—O2—C3	105.42 (8)
C7—C6—C5	118.12 (12)
O1—C2—C3—C4	−7.14 (19)	C5—C6—C7—C8	−0.38 (19)
C1—C2—C3—C4	170.61 (13)	C6—C7—C8—C9	0.0 (2)
O1—C2—C3—O2	177.75 (10)	C7—C8—C9—C10	0.4 (2)
C1—C2—C3—O2	−4.50 (17)	C8—C9—C10—O2	179.62 (12)
O2—C3—C4—N1	179.90 (11)	C8—C9—C10—C5	−0.31 (19)
C2—C3—C4—N1	4.4 (2)	C6—C5—C10—O2	179.99 (10)
O2—C3—C4—C5	0.84 (13)	C4—C5—C10—O2	0.20 (13)
C2—C3—C4—C5	−174.62 (11)	C6—C5—C10—C9	−0.08 (18)
N1—C4—C5—C10	−179.66 (12)	C4—C5—C10—C9	−179.86 (12)
C3—C4—C5—C10	−0.62 (12)	C9—C10—O2—C3	−179.64 (12)
N1—C4—C5—C6	0.6 (2)	C5—C10—O2—C3	0.29 (13)
C3—C4—C5—C6	179.64 (13)	C4—C3—O2—C10	−0.72 (13)
C10—C5—C6—C7	0.42 (17)	C2—C3—O2—C10	175.19 (10)
C4—C5—C6—C7	−179.88 (12)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1D···O1	0.86	2.28	2.8496 (14)	124
N1—H1E···O1^i	0.86	2.10	2.9122 (13)	158
C1—H1B···O1^ii	0.95 (2)	2.60 (2)	3.5473 (19)	174.3 (17)
C9—H9···O2^iii	1.004 (16)	2.545 (16)	3.5395 (16)	170.8 (12)

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