1-(4-Amino­phen­yl)-3-(3-bromo­phen­yl)prop-2-en-1-one

The title mol­ecule, C₁₅H₁₂BrNO, is approximately planar and the dihedral angle between the two aromatic rings is 9.6 (1)°. The crystal packing reveals that the mol­ecules translated by one unit cell along the a-axis direction are linked into a chain by inter­molecular N—H...O and C—H...O hydrogen-bonding inter­actions. The screw-related mol­ecules of adjacent chains are linked via N—H...N hydrogen bonds into a sheet-like structure parallel to the ab plane.

Key indicators

• Single-crystal X-ray study
• T = 273 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.030
• wR factor = 0.088
• Data-to-parameter ratio = 31.2

checkCIF/PLATON results

No syntax errors found



Alert level C
ABSTM02_ALERT_3_C  The ratio of expected to reported Tmax/Tmin(RR) is > 1.10
            Tmin and Tmax reported:      0.324     0.640
            Tmin and Tmax expected:      0.248     0.612
            RR =      1.252
            Please check that your absorption correction is appropriate.
PLAT060_ALERT_3_C Ratio Tmax/Tmin (Exp-to-Rep) (too) Large .......       1.22
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.96
PLAT094_ALERT_2_C Ratio of Maximum / Minimum Residual Density ....       2.72
PLAT731_ALERT_1_C Bond    Calc     0.89(2), Rep    0.893(9) ......       2.22 su-Rat
              N1   -H1A     1.555   1.555

Alert level G
REFLT03_ALERT_1_G ALERT: Expected hkl max differ from CIF values
           From the CIF: _diffrn_reflns_theta_max           38.16
           From the CIF: _reflns_number_total               5338
           From the CIF: _diffrn_reflns_limit_ max hkl   13.    8.   27.
           From the CIF: _diffrn_reflns_limit_ min hkl  -13.   -7.  -27.
           TEST1: Expected hkl limits for theta max
           Calculated maximum hkl   13.    8.   29.
           Calculated minimum hkl  -13.   -8.  -29.
REFLT03_ALERT_4_G  WARNING: Large fraction of Friedel related reflns may
                     be needed to determine absolute structure
           From the CIF: _diffrn_reflns_theta_max           38.16
           From the CIF: _reflns_number_total               5338
           Count of symmetry unique reflns         3762
           Completeness (_total/calc)            141.89%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured      1576
           Fraction of Friedel pairs measured     0.419
           Are heavy atom types Z>Si present        yes

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   5 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
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion


checkCIF publication errors

Alert level A
PUBL023_ALERT_1_A There is a mismatched ^ on line 379
              Refinement of F2^ against ALL reflections.  The weighted R-factor wR and
              If you require a ^ then it should be escaped
              with a \, i.e. \^
              Otherwise there must be a matching closing ~, e.g. ^12^C
PUBL023_ALERT_1_A There is a mismatched ^ on line 380
              goodness of fit S are based on F2^, conventional R-factors R are based
              If you require a ^ then it should be escaped
              with a \, i.e. \^
              Otherwise there must be a matching closing ~, e.g. ^12^C
PUBL023_ALERT_1_A There is a mismatched ^ on line 381
              on F, with F set to zero for negative F2^. The threshold expression of
              If you require a ^ then it should be escaped
              with a \, i.e. \^
              Otherwise there must be a matching closing ~, e.g. ^12^C
PUBL023_ALERT_1_A There is a mismatched ^ on line 384
              on F2^ are statistically about twice as large as those based on F, and R-
              If you require a ^ then it should be escaped
              with a \, i.e. \^
              Otherwise there must be a matching closing ~, e.g. ^12^C

   4 ALERT level A = Data missing that is essential or data in wrong format
   0 ALERT level G = General alerts. Data that may be required is missing

---

S1. Comment

Chalcones (1,3-diarylpropen-1-ones) and their heterocyclic analogues possess a number of biological attributes and some of these have been reviewed. The antibacterial, fungistatic and fungicidal properties of these compounds have been reviewed by Opletalova (2000) and Opletalova & Sedivy (1999). The cytotoxic, anticancer, chemopreventative, mutagenic, antimicrobial, antiviral, antiprotozoal and insecticidal activities and enzyme-inhibitory properties of a variety of chalcones have also been reviewed (Dimmock et al., 1999). Photo-cross-linkable polymers containing the chalcone group act as negative photo resist materials used in a wide variety of applications (Balaji et al., 2003). Chalcones are also used in designing effective second-order non-linear optical materials (Zhao et al., 2000). The structure determination of the title compound, (I), was undertaken as part of our study of chalcones.

Bond lengths and angles in (I) are comparable with those reported for related structures (Sathiya Moorthi, Chinnakali, Nanjundan, Radhika et al., 2005; Sathiya Moorthi, Chinnakali, Nanjundan, Selvam et al., 2005; Sathiya Moorthi, Chinnakali, Nanjundan, Unnithan et al., 2005) The short H5···H8 (2.24 Å) contact causes the bond angles C5—C6—C7 [123.07 (14)°] and C6—C7—C8 [126.76 (14)°] to deviate significantly from 120°. Also, the short H8···H11 (2.08 Å) contact results in a slight widening of the C9—C10—C11 angle to 122.97 (15)°. The sum of the angles around atom N1 is 349.7° and the deviation of atom N1 from the C13/H1A/H1B plane is 0.19 (2) Å, indicating its pyramidal nature.

The molecule of (I) (Fig. 1) is approximately planar. The enone fragment of the molecule containing atoms C7, C8, C9 and O1 is planar within ±0.022 (2) Å. This plane makes dihedral angles of 3.1 (1) and 7.1 (1)°, respectively, with the C1–C6 and C10–C15 benzene rings. The dihedral angle between the benzene rings is 9.6 (1)°. The H atoms attached to C7 and C8 are trans to each other.

The weak intramolecular C7—H7···O1 interaction generates an S(5) ring motif. In the crystal structure, the molecules translated by one unit cell along the a-axis direction are linked by N1—H1A···O1ⁱ and C12—H12···O1ⁱ [symmetry code: (i) 1 + x, y, z] hydrogen-bonding interactions to form a chain (Table 1). These interactions together constitute a pair of bifurcated acceptor bonds, generating an R₂¹(6) motif (Bernstein et al., 1995). The screw-related molecules of adjacent chains are linked via N1—H1B···N1ⁱⁱ [symmetry code: (ii) 2 − x, 1/2 + y, −z] hydrogen bonds into a sheet-like structure parallel to the ab plane (Fig. 2).

S2. Experimental

Compound (I) was obtained by the Claisen–Schmidt condensation of 4-aminoacetophenone (5.4 g, 0.04 mol) and 3-bromobenzaldehyde (7.4 g, 0.04 mol) in a 20% solution of NaOH and ethanol at 273 K over a period of 24 h. The product was isolated by neutralizing the reaction mixture with dilute hydrochloric acid. The crude product was recrystallized from ethanol.

S3. Refinement

Amino H atoms were located in a difference Fourier map and both positional and isotropic displacement parameters were refined, with an N—H distance restraint of 0.90 (1) Å. The C-bound H atoms were placed in calculated positions and constrained to ride on their parent atoms, with C—H = 0.93 Å and U_iso(H) = 1.2U_eq(C). The highest residual electron-density peak is located 0.76 Å from atom Br1.

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; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2003).

Figures

	Fig. 1. The structure of (I), showing the atomic numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. The dashed line indicates a hydrogen bond.
	Fig. 2. View of the hydrogen-bonded (dashed lines) sheets of (I).

1-(4-Aminophenyl)-3-(3-bromophenyl)prop-2-en-1-one

Crystal data

C15H12BrNO	F(000) = 304
Mr = 302.17	Dx = 1.594 Mg m^−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 6184 reflections
a = 8.0012 (2) Å	θ = 2.6–37.8°
b = 4.6257 (1) Å	µ = 3.25 mm^−1
c = 17.1148 (5) Å	T = 273 K
β = 96.413 (1)°	Block, colourless
V = 629.47 (3) Å^3	0.45 × 0.40 × 0.15 mm
Z = 2

Data collection

Bruker SMART APEX2 CCD area-detector diffractometer	5338 independent reflections
Radiation source: fine-focus sealed tube	4831 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.023
Detector resolution: 8.33 pixels mm^-1	θmax = 38.2°, θmin = 1.2°
ω scans	h = −13→13
Absorption correction: multi-scan (SADABS; Bruker, 2005)	k = −7→8
Tmin = 0.324, Tmax = 0.640	l = −27→27
9718 measured 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)] = 0.030	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.088	w = 1/[σ^2(Fo^2) + (0.0546P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.09	(Δ/σ)max = 0.001
5338 reflections	Δρmax = 1.36 e Å^−3
171 parameters	Δρmin = −0.50 e Å^−3
3 restraints	Absolute structure: Flack (1983), 1968 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.008 (6)

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	−0.101835 (19)	−0.32301 (7)	0.403165 (9)	0.02839 (5)
O1	0.28559 (15)	0.7796 (3)	0.13955 (8)	0.0241 (2)
N1	1.01570 (17)	1.1488 (4)	0.06315 (9)	0.0226 (3)
H1A	1.108 (2)	1.089 (8)	0.0931 (12)	0.036 (10)*
H1B	1.010 (3)	1.323 (3)	0.0412 (14)	0.030 (7)*
C1	0.12750 (19)	0.0295 (4)	0.32979 (10)	0.0196 (3)
H1	0.0317	0.0941	0.2990	0.024*
C2	0.1135 (2)	−0.1747 (4)	0.38803 (10)	0.0210 (3)
C3	0.2535 (2)	−0.2749 (4)	0.43574 (10)	0.0243 (4)
H3	0.2425	−0.4107	0.4749	0.029*
C4	0.4106 (2)	−0.1665 (4)	0.42336 (11)	0.0234 (3)
H4	0.5057	−0.2316	0.4547	0.028*
C5	0.4282 (2)	0.0370 (4)	0.36519 (10)	0.0213 (3)
H5	0.5344	0.1063	0.3578	0.026*
C6	0.28545 (18)	0.1388 (3)	0.31727 (9)	0.0181 (3)
C7	0.2948 (2)	0.3528 (4)	0.25505 (10)	0.0190 (3)
H7	0.1938	0.4031	0.2259	0.023*
C8	0.4334 (2)	0.4839 (4)	0.23566 (10)	0.0203 (3)
H8	0.5372	0.4376	0.2628	0.024*
C9	0.42462 (17)	0.7008 (5)	0.17196 (9)	0.0183 (3)
C10	0.58089 (19)	0.8209 (4)	0.14734 (9)	0.0175 (3)
C11	0.74161 (18)	0.7208 (4)	0.17693 (10)	0.0210 (3)
H11	0.7514	0.5784	0.2155	0.025*
C12	0.88468 (19)	0.8295 (4)	0.14996 (10)	0.0204 (3)
H12	0.9893	0.7585	0.1703	0.024*
C13	0.87471 (19)	1.0464 (4)	0.09210 (9)	0.0180 (3)
C14	0.71372 (18)	1.1462 (4)	0.06155 (9)	0.0199 (3)
H14	0.7037	1.2868	0.0225	0.024*
C15	0.57144 (19)	1.0367 (4)	0.08926 (9)	0.0190 (3)
H15	0.4666	1.1073	0.0690	0.023*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Br1	0.02547 (7)	0.02900 (9)	0.03259 (9)	−0.00492 (8)	0.01165 (5)	0.00037 (9)
O1	0.0150 (4)	0.0279 (6)	0.0295 (6)	0.0018 (4)	0.0021 (4)	0.0067 (5)
N1	0.0178 (4)	0.0220 (8)	0.0284 (6)	0.0003 (5)	0.0050 (4)	0.0048 (6)
C1	0.0187 (6)	0.0179 (6)	0.0226 (7)	0.0000 (5)	0.0039 (5)	−0.0013 (5)
C2	0.0222 (6)	0.0195 (7)	0.0224 (7)	−0.0020 (6)	0.0070 (5)	−0.0014 (5)
C3	0.0276 (7)	0.0259 (11)	0.0198 (7)	−0.0009 (6)	0.0049 (5)	0.0018 (5)
C4	0.0246 (7)	0.0237 (8)	0.0212 (7)	−0.0005 (6)	0.0000 (5)	0.0024 (6)
C5	0.0211 (6)	0.0195 (7)	0.0231 (8)	−0.0007 (5)	0.0011 (5)	0.0009 (5)
C6	0.0192 (5)	0.0140 (8)	0.0214 (6)	0.0000 (5)	0.0034 (4)	−0.0003 (5)
C7	0.0186 (6)	0.0167 (6)	0.0218 (7)	0.0004 (5)	0.0031 (5)	0.0003 (5)
C8	0.0176 (6)	0.0203 (7)	0.0232 (7)	0.0007 (5)	0.0029 (5)	0.0019 (5)
C9	0.0159 (4)	0.0181 (7)	0.0209 (6)	0.0006 (6)	0.0025 (4)	0.0008 (6)
C10	0.0157 (5)	0.0182 (6)	0.0186 (7)	0.0004 (5)	0.0022 (4)	0.0004 (5)
C11	0.0168 (5)	0.0235 (10)	0.0227 (7)	0.0026 (5)	0.0020 (4)	0.0046 (5)
C12	0.0148 (5)	0.0224 (7)	0.0239 (7)	0.0031 (5)	0.0017 (5)	0.0040 (5)
C13	0.0169 (5)	0.0171 (6)	0.0199 (7)	0.0004 (5)	0.0022 (4)	−0.0008 (5)
C14	0.0179 (5)	0.0188 (8)	0.0229 (6)	0.0012 (5)	0.0016 (4)	0.0039 (5)
C15	0.0164 (5)	0.0197 (7)	0.0206 (7)	0.0018 (5)	0.0007 (5)	0.0018 (5)

Geometric parameters (Å, º)

Br1—C2	1.8987 (17)	C7—C8	1.338 (2)
O1—C9	1.2410 (17)	C7—H7	0.93
N1—C13	1.367 (2)	C8—C9	1.477 (3)
N1—H1A	0.893 (9)	C8—H8	0.93
N1—H1B	0.889 (10)	C9—C10	1.472 (2)
C1—C2	1.387 (2)	C10—C15	1.405 (2)
C1—C6	1.400 (2)	C10—C11	1.407 (2)
C1—H1	0.93	C11—C12	1.376 (2)
C2—C3	1.390 (2)	C11—H11	0.93
C3—C4	1.391 (3)	C12—C13	1.406 (2)
C3—H3	0.93	C12—H12	0.93
C4—C5	1.389 (3)	C13—C14	1.413 (2)
C4—H4	0.93	C14—C15	1.378 (2)
C5—C6	1.411 (2)	C14—H14	0.93
C5—H5	0.93	C15—H15	0.93
C6—C7	1.462 (2)
C13—N1—H1A	110.3 (19)	C7—C8—C9	121.21 (14)
C13—N1—H1B	117.4 (19)	C7—C8—H8	119.4
H1A—N1—H1B	122 (3)	C9—C8—H8	119.4
C2—C1—C6	120.19 (15)	O1—C9—C10	120.59 (17)
C2—C1—H1	119.9	O1—C9—C8	119.71 (15)
C6—C1—H1	119.9	C10—C9—C8	119.70 (12)
C1—C2—C3	121.63 (16)	C15—C10—C11	117.61 (15)
C1—C2—Br1	119.45 (13)	C15—C10—C9	119.36 (14)
C3—C2—Br1	118.91 (14)	C11—C10—C9	122.97 (15)
C2—C3—C4	118.24 (17)	C12—C11—C10	121.35 (15)
C2—C3—H3	120.9	C12—C11—H11	119.3
C4—C3—H3	120.9	C10—C11—H11	119.3
C5—C4—C3	121.27 (16)	C11—C12—C13	120.86 (14)
C5—C4—H4	119.4	C11—C12—H12	119.6
C3—C4—H4	119.4	C13—C12—H12	119.6
C4—C5—C6	120.18 (16)	N1—C13—C12	121.24 (14)
C4—C5—H5	119.9	N1—C13—C14	120.53 (15)
C6—C5—H5	119.9	C12—C13—C14	118.15 (15)
C1—C6—C5	118.48 (15)	C15—C14—C13	120.46 (16)
C1—C6—C7	118.44 (13)	C15—C14—H14	119.8
C5—C6—C7	123.07 (14)	C13—C14—H14	119.8
C8—C7—C6	126.76 (14)	C14—C15—C10	121.57 (14)
C8—C7—H7	116.6	C14—C15—H15	119.2
C6—C7—H7	116.6	C10—C15—H15	119.2
C6—C1—C2—C3	0.5 (3)	O1—C9—C10—C15	3.1 (3)
C6—C1—C2—Br1	−179.30 (13)	C8—C9—C10—C15	−177.10 (17)
C1—C2—C3—C4	−0.5 (3)	O1—C9—C10—C11	−174.06 (18)
Br1—C2—C3—C4	179.30 (14)	C8—C9—C10—C11	5.7 (3)
C2—C3—C4—C5	0.2 (3)	C15—C10—C11—C12	−0.1 (3)
C3—C4—C5—C6	0.2 (3)	C9—C10—C11—C12	177.07 (17)
C2—C1—C6—C5	−0.2 (2)	C10—C11—C12—C13	0.4 (3)
C2—C1—C6—C7	179.75 (15)	C11—C12—C13—N1	−177.84 (17)
C4—C5—C6—C1	−0.2 (3)	C11—C12—C13—C14	−1.0 (3)
C4—C5—C6—C7	179.93 (17)	N1—C13—C14—C15	178.15 (16)
C1—C6—C7—C8	178.77 (17)	C12—C13—C14—C15	1.3 (3)
C5—C6—C7—C8	−1.3 (3)	C13—C14—C15—C10	−1.0 (3)
C6—C7—C8—C9	−179.00 (17)	C11—C10—C15—C14	0.4 (3)
C7—C8—C9—O1	5.4 (3)	C9—C10—C15—C14	−176.88 (17)
C7—C8—C9—C10	−174.40 (17)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O1^i	0.89 (2)	2.11 (3)	2.943 (2)	155 (3)
N1—H1B···N1^ii	0.89 (2)	2.33 (2)	3.157 (2)	155 (2)
C7—H7···O1	0.93	2.45	2.789 (2)	102
C12—H12···O1^i	0.93	2.49	3.241 (2)	138

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