5-Chloro-1-phenyl­pentan-1-one

Bechmann, N.; Kniess, T.; Pietzsch, J.; König, J.; Köckerling, M.

doi:10.1107/S2414314616000559

organic compounds

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ISSN: 2414-3146

Volume 1| Part 1| January 2016| x160055

doi:10.1107/S2414314616000559

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5-Chloro-1-phenylpentan-1-one

Nicole Bechmann,^a,^b Torsten Kniess,^a Jens Pietzsch,^a,^b Jonas König ^c and Martin Köckerling ^c ^*

^aInstitut für Radiopharmazeutische Krebsforschung, Helmholtz-Zentrum Dresden-Rossendorf e.V., Postfach 51 01 19, D-01314 Dresden, Germany, ^bDepartment of Chemistry and Food Chemistry, Technische Universität Dresden, D-01062 Dresden, Germany, and ^cUniversität Rostock, Institut für Chemie, Anorganische Festkörperchemie, Albert-Einstein-Strasse 3a, D-18059 Rostock, Germany
^*Correspondence e-mail: martin.koeckerling@uni-rostock.de

Edited by V. V. Chernyshev, Moscow State University, Russia (Received 29 December 2015; accepted 11 January 2016; online 23 January 2016)

In the title compound, C₁₁H₁₃ClO, which is used as a starting material for the synthesis of some materials with possible medical applications, the molecular skeleton is slightly curved, with the dihedral angle of 4.7 (1)° between the mean planes of the chlorobutane and benzaldehyde fragments. In the crystal, weak C—H⋯O hydrogen bonds link the molecules into chains running along the [201] direction, and weak C—H⋯π interactions link these chains into layers parallel to the ac plane.

Keywords: crystal structure; δ-chlorobutyl phenyl ketone; hyrogen bonding.

CCDC reference: 1446638

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Chemical scheme

Structure description

The synthesis of the title compound, (I), was previously described in the preparation of building blocks for the synthesis of ω-phenylalkylpyrimidines and purines (Komissarov et al. 2010 ; Gromov et al. 1999 ). Another application is the use as coupling component for the synthesis of acyclic triaryl olefins, which were described as selective cyclooxygenase-2 inhibitors (Abdellatif et al., 2010 , 2011 ; Uddin et al. 2004a ,b ) and selective estrogen receptor modulators (Chen et al., 2012 ; Shiina et al. 2007 ). In our study, (I) was obtained as product of the reaction of 5-chlorovaleryl chloride with benzene in the presence of aluminium chloride via Friedel–Crafts acylation.

The molecule of (I) (Fig. 1) is nearly flat, but not completely planar - the two mean planes formed by the chlorobutane (Cl1/C1–C4) fragment and by the rest of non-H atoms, respectively, are inclined to each other by 4.7 (1)°. In the crystal, weak C—H⋯O hydrogen bonds (Table 1) link the molecules into chains running along [201]. Weak C—H⋯π interactions (Table 1) link these chains into layers parallel to the ac plane. Van der Waals forces stabilize further the crystal packing (Fig. 2).

Table 1
Hydrogen-bond geometry (Å, °)

Cg is the centroid of the C6–C11 benzene ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C11—H11⋯O1ⁱ	0.95	2.51	3.422 (2)	169
C2—H2A⋯Cgⁱⁱ	0.99	2.80	3.676 (2)	148
Symmetry codes: (i) $[x+1, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ ; (ii) $[x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ .

Figure 1
The molecular structure of (I), with atom labels and 50% probability displacement ellipsoids for non-H atoms.

Figure 2
A portion of the crystal packing, viewed approximately along the a axis.

Synthesis and crystallization

To an ice-cold suspension of aluminium chloride (1.76 g, 13.23 mmol) in 10 ml chloroform, 1.86 ml 5-chlorovaleryl chloride (14.40 mmol) and 0.99 ml benzene (11.54 mmol) were added under an argon atmosphere. After stirring for 1.5 h at room temperature, the reaction mixture was poured into a mixture of ice and water (15 ml). The organic layer was separated and washed three times with water (10 ml). The separated aqueous solution was extracted three times with CHCl₃ (15 ml), the combined organic layer was dried over Na₂SO₄ and the solvent was removed under vacuum. After purification with semi-preparative HPLC (ProStar; Varian; microsorb 60, C18; water/acetonitrile + 0.1% TFA; 35 min: 5/5, v/v; 7 ml min⁻¹). 5-Chloro-1-phenylpentan-1-one was obtained as a yellow solid in 91.6% yield. Colorless crystals were obtained by crystallization from acetonitrile/water + 0.1% TFA after chromatographic separation.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2.

Table 2
Experimental details

Crystal data
Chemical formula	C₁₁H₁₃ClO
M_r	196.66
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	173
a, b, c (Å)	5.2434 (4), 25.902 (2), 7.7027 (6)
β (°)	104.756 (5)
V (Å³)	1011.6 (1)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.33
Crystal size (mm)	0.32 × 0.27 × 0.26

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2007 )
No. of measured, independent and observed [I > 2σ(I)] reflections	9116, 2343, 1411
R_int	0.042
(sin θ/λ)_max (Å⁻¹)	0.652

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.043, 0.108, 1.01
No. of reflections	2343
No. of parameters	119
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.31
Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008 ), SHELXL2014 (Sheldrick, 2015 ), SHELXTL (Sheldrick, 2008).

Structural data

CCDC reference: 1446638

Crystal structure: contains datablock I. DOI: 10.1107/S2414314616000559/cv4001sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S2414314616000559/cv4001Isup2.hkl

Supporting information file. DOI: 10.1107/S2414314616000559/cv4001Isup3.cml

checkCIF report

Comment top

The synthesis of the title compound, (I), was previously described in the preparation of building blocks for the synthesis of ω-phenylalkylpyrimidines and purines (Komissarov et al. 2010; Gromov et al. 1999). Another application is the use as coupling component for the synthesis of acyclic triaryl olefins, which were described as selective cyclooxygenase-2 inhibitors (Abdellatif et al., 2010, 2011; Uddin et al. 2004a,b) and selective estrogen receptor modulators (Chen et al., 2012; Shiina et al. 2007). In our study, (I) was obtained as product of the reaction of 5-chlorovaleryl chloride with benzene in the presence of aluminium chloride via Friedel-Crafts acylation.

The molecule of (I) (Fig. 1) is nearly flat, but not completely planar - two mean planes formed by the chlorobutane (Cl1/C1—C4) fragment and by the rest of non-H atoms, respectively, are inclined to each other at 4.7 (1)%. In the crystal, weak intermolecular C—H···O hydrogen bonds (Table 1) link the molecules into chains running in [201], and weak C—H···π interactions (Table 1) link these chains into layers parallel to the ac plane. Van der Waals forces stabilize further the crystal packing (Fig. 2).

Experimental top

To an ice-cold suspension of aluminium chloride (1.76 g, 13.23 mmol) in 10 ml chloroform, 1.86 ml 5-chlorovaleryl chloride (14.40 mmol) and 0.99 ml benzene (11.54 mmol) were added under an argon atmosphere. After stirring for 1.5 h at room temperature, the reaction mixture was poured into a mixture of ice and water (15 ml). The organic layer was separated and washed three times with water (10 ml). The separated aqueous solution was extracted three times with CHCl₃ (15 ml), the combined organic layer was dried over Na₂SO₄ and the solvent was removed under vacuum. After purification with semi-preparative HPLC (ProStar; Varian; microsorb 60, C18; water/acetonitrile + 0.1% TFA; 35 min: 5/5, v/v; 7 ml min⁻¹) 5-chloro-1-phenylpentan-1-one was obtained as a yellow solid in 91.6% yield. Colorless crystals were obtained by crystallization from acetonitrile/water + 0.1% TFA after chromatographic separation.

Structure description top

The synthesis of the title compound, (I), was previously described in the preparation of building blocks for the synthesis of ω-phenylalkylpyrimidines and purines (Komissarov et al. 2010; Gromov et al. 1999). Another application is the use as coupling component for the synthesis of acyclic triaryl olefins, which were described as selective cyclooxygenase-2 inhibitors (Abdellatif et al., 2010, 2011; Uddin et al. 2004a,b) and selective estrogen receptor modulators (Chen et al., 2012; Shiina et al. 2007). In our study, (I) was obtained as product of the reaction of 5-chlorovaleryl chloride with benzene in the presence of aluminium chloride via Friedel–Crafts acylation.

The molecule of (I) (Fig. 1) is nearly flat, but not completely planar - two mean planes formed by the chlorobutane (Cl1/C1–C4) fragment and by the rest of non-H atoms, respectively, are inclined to each other by 4.7 (1)°. In the crystal, weak C—H···O hydrogen bonds (Table 1) link the molecules into chains running along [201]. Weak C—H···π interactions (Table 1) link these chains into layers parallel to the ac plane. van der Waals forces stabilize further the crystal packing (Fig. 2).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of (I), with atom labels and 50% probability displacement ellipsoids for non-H atoms.
	Fig. 2. A portion of the crystal packing, viewed approximately along the a axis.

5-Chloro-1-phenylpentan-1-one top

Crystal data top

C₁₁H₁₃ClO	D_x = 1.291 Mg m⁻³
M_r = 196.66	Melting point = 320–321 K
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 5.2434 (4) Å	Cell parameters from 1422 reflections
b = 25.902 (2) Å	θ = 2.9–22.7°
c = 7.7027 (6) Å	µ = 0.33 mm⁻¹
β = 104.756 (5)°	T = 173 K
V = 1011.6 (1) Å³	Irregular block, colorless
Z = 4	0.32 × 0.27 × 0.26 mm
F(000) = 416

Data collection top

Bruker APEXII CCD diffractometer	2343 independent reflections
Radiation source: sealed tube	1411 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.042
φ and ω scans	θ_max = 27.6°, θ_min = 1.6°
Absorption correction: multi-scan (SADABS; Bruker, 2007)	h = −6→5
	k = −33→29
9116 measured reflections	l = −10→10

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.043	H-atom parameters constrained
wR(F²) = 0.108	w = 1/[σ²(F_o²) + (0.0362P)² + 0.2948P] where P = (F_o² + 2F_c²)/3
S = 1.01	(Δ/σ)_max < 0.001
2343 reflections	Δρ_max = 0.22 e Å⁻³
119 parameters	Δρ_min = −0.31 e Å⁻³
0 restraints	Extinction correction: SHELXL2014 (Sheldrick, 2015), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0021 (13)

Crystal data top

C₁₁H₁₃ClO	V = 1011.6 (1) Å³
M_r = 196.66	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 5.2434 (4) Å	µ = 0.33 mm⁻¹
b = 25.902 (2) Å	T = 173 K
c = 7.7027 (6) Å	0.32 × 0.27 × 0.26 mm
β = 104.756 (5)°

Data collection top

Bruker APEXII CCD diffractometer	2343 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2007)	1411 reflections with I > 2σ(I)
	R_int = 0.042
9116 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.043	0 restraints
wR(F²) = 0.108	H-atom parameters constrained
S = 1.01	Δρ_max = 0.22 e Å⁻³
2343 reflections	Δρ_min = −0.31 e Å⁻³
119 parameters

Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Cl1	0.30681 (13)	0.47935 (2)	0.72353 (9)	0.0622 (2)
C1	0.0779 (4)	0.42960 (8)	0.6269 (3)	0.0403 (5)
H1A	−0.0813	0.4326	0.6731	0.048*
H1B	0.0231	0.4340	0.4949	0.048*
C2	0.1990 (4)	0.37676 (7)	0.6714 (2)	0.0330 (5)
H2A	0.2507	0.3722	0.8033	0.040*
H2B	0.3602	0.3741	0.6274	0.040*
C3	0.0082 (4)	0.33416 (8)	0.5870 (2)	0.0335 (5)
H3A	−0.0485	0.3395	0.4555	0.040*
H3B	−0.1503	0.3360	0.6342	0.040*
C4	0.1323 (4)	0.28088 (7)	0.6257 (2)	0.0311 (5)
H4A	0.2869	0.2788	0.5744	0.037*
H4B	0.1961	0.2763	0.7573	0.037*
C5	−0.0547 (4)	0.23775 (8)	0.5504 (2)	0.0322 (5)
O1	−0.2751 (3)	0.24672 (6)	0.4561 (2)	0.0515 (4)
C6	0.0313 (4)	0.18322 (8)	0.5912 (2)	0.0286 (4)
C7	−0.1480 (4)	0.14405 (8)	0.5232 (2)	0.0342 (5)
H7	−0.3185	0.1527	0.4514	0.041*
C8	−0.0816 (4)	0.09289 (8)	0.5587 (3)	0.0395 (5)
H8	−0.2066	0.0665	0.5128	0.047*
C9	0.1679 (4)	0.07998 (8)	0.6614 (3)	0.0386 (5)
H9	0.2143	0.0448	0.6855	0.046*
C10	0.3486 (4)	0.11831 (8)	0.7284 (3)	0.0352 (5)
H10	0.5196	0.1093	0.7983	0.042*
C11	0.2830 (4)	0.16993 (8)	0.6946 (2)	0.0307 (5)
H11	0.4085	0.1961	0.7416	0.037*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0628 (5)	0.0355 (4)	0.0776 (5)	0.0012 (3)	−0.0018 (3)	0.0025 (3)
C1	0.0395 (12)	0.0400 (13)	0.0373 (11)	0.0058 (10)	0.0023 (9)	0.0023 (9)
C2	0.0318 (11)	0.0358 (12)	0.0297 (10)	0.0081 (9)	0.0044 (8)	0.0026 (9)
C3	0.0306 (11)	0.0396 (12)	0.0283 (10)	0.0074 (9)	0.0040 (8)	0.0010 (9)
C4	0.0279 (10)	0.0366 (12)	0.0276 (9)	0.0028 (9)	0.0045 (8)	0.0003 (8)
C5	0.0270 (11)	0.0430 (13)	0.0257 (10)	0.0004 (9)	0.0049 (8)	−0.0009 (9)
O1	0.0338 (9)	0.0503 (10)	0.0572 (10)	0.0034 (8)	−0.0125 (7)	0.0044 (8)
C6	0.0267 (10)	0.0379 (12)	0.0214 (9)	−0.0013 (9)	0.0064 (8)	−0.0006 (8)
C7	0.0283 (11)	0.0438 (13)	0.0294 (10)	−0.0034 (10)	0.0051 (8)	−0.0007 (9)
C8	0.0358 (12)	0.0437 (14)	0.0397 (11)	−0.0112 (10)	0.0106 (10)	−0.0052 (10)
C9	0.0423 (13)	0.0343 (13)	0.0418 (12)	0.0003 (10)	0.0153 (10)	0.0009 (10)
C10	0.0306 (11)	0.0391 (13)	0.0354 (11)	0.0046 (10)	0.0076 (9)	0.0020 (9)
C11	0.0248 (10)	0.0371 (12)	0.0287 (10)	−0.0013 (9)	0.0042 (8)	−0.0021 (8)

Geometric parameters (Å, º) top

Cl1—C1	1.789 (2)	C5—O1	1.221 (2)
C1—C2	1.511 (3)	C5—C6	1.491 (3)
C1—H1A	0.9900	C6—C7	1.392 (3)
C1—H1B	0.9900	C6—C11	1.400 (2)
C2—C3	1.520 (3)	C7—C8	1.380 (3)
C2—H2A	0.9900	C7—H7	0.9500
C2—H2B	0.9900	C8—C9	1.386 (3)
C3—C4	1.522 (3)	C8—H8	0.9500
C3—H3A	0.9900	C9—C10	1.379 (3)
C3—H3B	0.9900	C9—H9	0.9500
C4—C5	1.502 (3)	C10—C11	1.389 (3)
C4—H4A	0.9900	C10—H10	0.9500
C4—H4B	0.9900	C11—H11	0.9500

C2—C1—Cl1	111.07 (14)	H4A—C4—H4B	107.7
C2—C1—H1A	109.4	O1—C5—C6	119.69 (18)
Cl1—C1—H1A	109.4	O1—C5—C4	120.95 (19)
C2—C1—H1B	109.4	C6—C5—C4	119.36 (16)
Cl1—C1—H1B	109.4	C7—C6—C11	118.92 (18)
H1A—C1—H1B	108.0	C7—C6—C5	118.17 (17)
C1—C2—C3	111.59 (16)	C11—C6—C5	122.92 (17)
C1—C2—H2A	109.3	C8—C7—C6	120.89 (18)
C3—C2—H2A	109.3	C8—C7—H7	119.6
C1—C2—H2B	109.3	C6—C7—H7	119.6
C3—C2—H2B	109.3	C7—C8—C9	119.90 (19)
H2A—C2—H2B	108.0	C7—C8—H8	120.0
C2—C3—C4	111.86 (15)	C9—C8—H8	120.0
C2—C3—H3A	109.2	C10—C9—C8	119.9 (2)
C4—C3—H3A	109.2	C10—C9—H9	120.0
C2—C3—H3B	109.2	C8—C9—H9	120.0
C4—C3—H3B	109.2	C9—C10—C11	120.62 (19)
H3A—C3—H3B	107.9	C9—C10—H10	119.7
C5—C4—C3	113.21 (15)	C11—C10—H10	119.7
C5—C4—H4A	108.9	C10—C11—C6	119.74 (18)
C3—C4—H4A	108.9	C10—C11—H11	120.1
C5—C4—H4B	108.9	C6—C11—H11	120.1
C3—C4—H4B	108.9

Hydrogen-bond geometry (Å, º) top

Cg is the centroid of the C6–C11 benzene ring.

D—H···A	D—H	H···A	D···A	D—H···A
C11—H11···O1ⁱ	0.95	2.51	3.422 (2)	169
C2—H2A···Cgⁱⁱ	0.99	2.80	3.676 (2)	148

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

Hydrogen-bond geometry (Å, º) top

Cg is the centroid of the C6–C11 benzene ring.

D—H···A	D—H	H···A	D···A	D—H···A
C11—H11···O1ⁱ	0.95	2.51	3.422 (2)	169
C2—H2A···Cgⁱⁱ	0.99	2.80	3.676 (2)	148

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

Experimental details

Crystal data
Chemical formula	C₁₁H₁₃ClO
M_r	196.66
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	173
a, b, c (Å)	5.2434 (4), 25.902 (2), 7.7027 (6)
β (°)	104.756 (5)
V (Å³)	1011.6 (1)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.33
Crystal size (mm)	0.32 × 0.27 × 0.26

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2007)
No. of measured, independent and observed [I > 2σ(I)] reflections	9116, 2343, 1411
R_int	0.042
(sin θ/λ)_max (Å⁻¹)	0.652

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.043, 0.108, 1.01
No. of reflections	2343
No. of parameters	119
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.31

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL2014 (Sheldrick, 2015), SHELXTL (Sheldrick, 2008).

Acknowledgements

Help with the X-ray diffraction experiments by Dr A. Villinger and Dipl.-Chem. P. Thiele (University of Rostock) is gratefully acknowledged.

References

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