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Crystal structures of two new 3-(2-chloro­eth­yl)-r(2),c(6)-di­arylpiperidin-4-ones

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aResearch and Development Centre, Bharathiar University, Coimbatore 641 046, Tamilnadu, India, bDepartment of Chemistry, Thiruvalluvar Arts and Science College, Kurinjipadi 607 302, Tamilnadu, India, cDepartment of Chemistry, Keene State College, 229 Main Street, Keene, NH, 03435-2001, USA, dDepartment of Chemistry, Annamalai University, Annamalai Nagar 608 002, Tamilnadu, India, and ePrincipal, Kunthavai Naacchiyaar Government Arts College for Women (Autonomous), Thanjavur 613 007, Tamilnadu, India
*Correspondence e-mail: sivakumar.phd2015@gmail.com, jjasinski@keene.edu

Edited by J. Simpson, University of Otago, New Zealand (Received 6 February 2018; accepted 4 March 2018; online 9 March 2018)

The syntheses and crystal structures of 3-(2-chloro­eth­yl)-r-2,c-6-di­phenyl­piperidin-4-one, C19H20ClNO, (I), and 3-(2-chloro­eth­yl)-r-2,c-6-bis­(4-fluoro­phen­yl)piperidin-4-one, C19H18ClF2NO, (II), are described. The piperidone ring adopts a chair conformation in (I), whereas a slightly distorted chair conformation is formed in (II). The dihedral angle between the mean plane of the phenyl rings is 59.1 (1)° in (I) and 76.1 (1)° in (II). The crystal packing features weak inter­molecular N—H⋯O hydrogen bonds in each structure.

1. Chemical context

Piperidone mol­ecules exhibit a wide spectrum of biological activities ranging from anti-bacterial to anti-cancer (Parthiban et al., 2005[Parthiban, P., Balasubramanian, S., Aridoss, G. & Kabilan, S. (2005). Med. Chem. Res. 14, 523-538.], 2009[Parthiban, P., Aridoss, G., Rathika, P., Ramkumar, V. & Kabilan, S. (2009). Bioorg. Med. Chem. Lett. 19, 2981-2985.], 2011[Parthiban, P., Pallela, R., Kim, S. K., Park, D. H. & Jeong, Y. T. (2011). Bioorg. Med. Chem. Lett. 21, 6678-6686.]). Most of the 2,6-diaryl-substituted piperidones and their derivatives are of significant pharmacological importance (Aridoss et al., 2007[Aridoss, G., Balasubramanian, S., Parthiban, P. & Kabilan, S. (2007). Spectrochim. Acta Part A, 68, 1153-1163.]). Some novel 3,5-di­chloro-2,6-di­aryl­piperidin-4-ones are also reported to possess anti­microbial activity (Bhakiaraj et al., 2014[Bhakiaraj, D., Elavarasan, T. & Gopalakrishnan, M. (2014). Pharma Chemica, 6(5), 243-250.]). Piperidones also display analgesic, anti-inflammatory, central nervous system (CNS), local anaesthetic, anti­cancer and anti­microbial activity (Perumal et al., 2001[Perumal, R. V., Agiraj, M. & Shanmugapandiyan, P. (2001). Indian Drugs, 38, 156-159.]). In view of the relevance of piperidone derivatives to a variety of ongoing health and pharmalogical issues, we have synthesized the title compounds and report their crystal structures here. Arulraj et al. (2017[Arulraj, R., Sivakumar, S., Kaur, M., Thiruvalluvar, A. & Jasinski, J. P. (2017). Acta Cryst. E73, 107-111.]) has reported the crystal structure of three related 3-chloro-3-methyl-2,6-di­aryl­piperidin-4-ones. In each of these structures, the piperidine rings adopt chair conformations similar to what we have observed in the title compounds.

[Scheme 1]

2. Structural commentary

Two new 3-(2-chloro­eth­yl)-r-2,c-6-di­aryl­piperidin-4-one compounds, C19H20ClNO (I)[link] and C19H18ClF2NO (II)[link], each crystallize in the P21/c space group with one independent mol­ecule in the asymmetric unit. The piperidone ring adopts a chair conformation in (I)[link], (Fig. 1[link]), whereas it forms a slightly distorted chair conformation in (II)[link], (Fig. 2[link]), with puckering parameters Q = 0.576 (2) Å, θ = 164.2 (2)°, φ = 179.4 (8)° in (I)[link] and Q = 0.601 (2) Å, θ = 4.93 (19)°, φ = 356 (2)° in (II)[link]. The dihedral angle between the mean planes of the phenyl rings is 59.1 (1)° in (I)[link] and 76.1 (1)° in (II)[link]. The increase in this dihedral angle in (II)[link] could be attributed to steric repulsion from the substituent fluorine atoms. The sum of the bond angles around N1 in each structure [332.5° in (I)[link] and 331.9° in (II)] is consistent with sp3 hybridization (Beddoes et al., 1986[Beddoes, R. L., Dalton, L., Joule, T. A., Mills, O. S., Street, J. D. & Watt, C. I. F. (1986). J. Chem. Soc. Perkin Trans. 2, pp. 787-797.]).

[Figure 1]
Figure 1
A view of the mol­ecular structure of (I)[link], showing displacement ellipsoids drawn at the 30% probability level.
[Figure 2]
Figure 2
A view of the mol­ecular structure of (II)[link], showing displacement ellipsoids drawn at the 30% probability level.

The substituents on the piperidine ring in both (I)[link] and (II)[link] adopt equatorial orientations with the keto oxygen atom being anti-clinal [O1—C3—C4—C5 = 136.1 (2)°] in (I)[link] and anti-periplanar [O1—C1—C5—C4 = −120.4 (2)°] in (II)[link]. The 2-chloro­ethyl group lies in a syn-clinal orientation in both (I)[link] [C3—C2—C18—C19 = 75.6 (3)°] and (II)[link] [C1—C5—C6—C7 = 76.4 (2)°]. The two diaryl groups are both anti-clinal [N1—C5—C6—C11 = 54.5 (3)° and N1—C1—C12—C13 = 123.97 (18)°] in (I)[link] whereas in (II)[link] they are both syn-clinal [N1—C4—C14—C15 = −78.4 (2)° and N1—C3—C8—C13 = 35.4 (2)°].

3. Supra­molecular features

The crystal packing features very weak N1—H1⋯O1 hydrogen bonds in (I)[link], forming infinite C(6) chains along the b-axis direction, with the mol­ecules rotating in a 180° spiral motif along the axis (Table 1[link], Fig. 3[link]). In addition, a weak C—H⋯π inter­action between the piperdine ring and a diaryl group in (I)[link] also occurs.

Table 1
Hydrogen-bond geometry (Å, °) for (I)[link]

Cg3 is the centroid of the C12–C17 ring.

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O1i 0.86 (2) 2.52 (2) 3.335 (2) 158 (2)
C4—H4ACg3ii 0.97 2.79 3.665 (2) 150
Symmetry codes: (i) [-x+1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) [-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}].
[Figure 3]
Figure 3
A partial view along the a axis of the crystal packing for (I)[link], showing infinite chains formed along [010] by weak N1—H1⋯O1 hydrogen bonds with the mol­ecules rotating in a 180° spiral motif along the axis. H atoms not involved in this inter­action have been omitted for clarity.

In (II)[link], weak N—H⋯O hydrogen bonds (Fig. 4[link], Table 2[link]) are again observed, also forming infinite C(6) chains but along the c axis in this case. Weak C—H⋯O and C—H⋯F inter­actions (Table 2[link]) are also observed and contribute to the packing stability. In (II)[link], the keto oxygen, O1, acts as the acceptor of weak hydrogen bonds involving atom N1 from a piperdine ring in the same plane and with atom C12 from one of the diaryl groups of a mol­ecule in an adjacent plane along the a axis. An unusual weak C1—O1⋯π [O1⋯π = 3.8263 (19) Å, C1⋯π = 4.377 (2) Å, C1—O1⋯π = 109°; x, [{1\over 2}] − y, −[{1\over 2}] + z; centroid of the C8–C13 ring] inter­action also between the piperidine ring and a diaryl group is observed.

Table 2
Hydrogen-bond geometry (Å, °) for (II)[link]

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O1i 0.89 (2) 2.32 (2) 3.189 (2) 165 (2)
C9—H9⋯F2ii 0.93 2.61 3.378 (2) 140
C10—H10⋯F2iii 0.93 2.58 3.343 (2) 139
C12—H12⋯O1iv 0.93 2.57 3.412 (3) 150
C16—H16⋯F1v 0.93 2.62 3.379 (2) 139
Symmetry codes: (i) [x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (ii) [x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]; (iii) [-x+1, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]; (iv) [x-1, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (v) [-x, y+{\script{1\over 2}}, -z+{\script{3\over 2}}].
[Figure 4]
Figure 4
A partial view along the a axis of the crystal packing for (II)[link], showing infinite chains formed along [001] by weak N1—H1⋯O1 and C12—H12⋯O1 hydrogen-bonding inter­actions. The keto oxygen, O1, forms a weak hydrogen bond with N1 from a piperdine ring in the same plane and with C12 from one of the diaryl groups of a mol­ecule in an adjacent plane along the a axis. H atoms not involved in these inter­actions have been omitted for clarity.

4. Database survey

A search in the Cambridge Crystallographic Database (CSD version 5.38 of Nov, 2016, updates May, 2017; Groom et al., 2016[Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171-179.]) for the 2,6-di­phenyl­piperidin-4-one skeleton resulted in 229 hits, which was further refined to 50 hits by removing those structures in which the title skeleton substructure was combined with larger mol­ecules. The two most closely related remaining structures based on the pendant arms of the 2,6-di­phenyl­piperidine-4-one central substructure, viz. 2,6-diphenyl-3-iso­propyl­piperidin-4-one (ACEZUD; Nilofar Nissa et al., 2001[Nilofar Nissa, M., Velmurugan, D., Narasimhan, S., Rajagopal, V. & Kim, M.-J. (2001). Acta Cryst. E57, o996-o998.]) and t-3-pentyl-r-2,c-6-di­phenyl­piperidin-4-one (RUGLOV; Gayathri et al., 2009[Gayathri, P., Jayabharathi, J., Rajarajan, G., Thiruvalluvar, A. & Butcher, R. J. (2009). Acta Cryst. E65, o3083.]) were then compared with the two reported here. The piperidone ring in compounds (I)[link] and (II)[link] reported here adopt chair or distorted chair conformations, unlike in ACEZUD and RUGLOV. The crystal packing is stabilized by N—H⋯O inter­molecular hydrogen bonds in both (I)[link] and (II)[link], as well as in ACEZUD. In contrast, the crystal packing in RUGLOV is influenced only by weak C—H⋯O and C—H⋯π inter­molecular inter­actions.

5. Synthesis and crystallization

A mixture of ammonium acetate (0.1 mol, 7.71 g), the respective aldehyde (0.2 mol), benzaldehyde/p-fluoro­benzaldehyde (20.4 ml/21.0 ml) and 5-chloro-2-penta­none (0.1 mol, 11.4 ml) in distilled ethanol was heated first to boiling. After cooling, the viscous liquid obtained was dissolved in diethyl ether (200 ml) and shaken with 100 ml of concentrated hydro­chloric acid. The precipitated hydro­chlorides of the 3-(2-chloro­eth­yl)-r-2,c-6-di­aryl­piperidin-4-ones were removed by filtration and washed first with a 40 ml mixture of ethanol and diethyl ether (1:1) and then with diethyl ether to remove most of the coloured impurities. The base was liberated from an alcoholic solution by adding aqueous ammonia and then diluted with water. Each compound was recrystallized twice from a distilled ethanol solution: single crystals of (I)[link] and (II)[link] were obtained after two days. The yield of the isolated product was 3.0 g (I)[link] and 2.5 g (II)[link].

3-(2-Chloro­eth­yl)-r-2,c-6-di­phenyl­piperidin-4-one, (C19H20ClNO), (I)[link]:

IR (KBr): 3311.07 (νN—H), 3067.56, 3033.34 (νC—H), 1697.03 (νC=O), 1605.39, 1493.90 (νC=C), 769.33 (νC—Cl) cm−1. 1H NMR (400 MHz, CDCl3): δ 7.42–7.19 (m, aromatic protons), 4.03 (d, H6 proton), 3.64 (d, H2 proton), 3.36–3.33 (m, H5a proton), 2.61 (dd, H5e proton), 2.18–2.09 (m, H3 proton, 1.99 (s, NH proton), 2.94 (s, CH2Cl proton), 2.75 (t, CH2 proton). 13C NMR (CDCl3, 400 MHz): δ 208.60 (C=O), 140.67 (aromatic ipso carbon atoms), 128.81–126.63 (aromatic carbon atoms), 67.27 (C-3 carbon), 61.92 (C-2 carbon), 53.76 (C-6 carbon), 51.27 (C-5 carbon), 28.18 (methyl­ene carbon), 43.49 (CH2Cl Carbon). Melting point: 371 K.

3-(2-Chloro­eth­yl)-r-2,c-6-bis­(p-fluoro­phen­yl)piperidin-4-one, (C19H18ClF2NO), (II)[link]:

IR (KBr): 3292.53 (νN—H), 3078.27, 3077.86 (νC—H), 1702.32 (νC=O), 1605.79, 1511.47 (νC=C), 760.50 (νC—Cl) cm−1. 1H NMR (400 MHz, CDCl3): δ 7.39–7.02 (m, aromatic protons), 3.99 (dd, H6 proton), 3.61 (d, H2 proton), 3.36 (dd, H5a proton), 2.52 (dd, H5e proton), 2.16–2.08 (m, H3 proton), 1.99 (s, NH proton), 2.84 (t, CH2Cl proton), 2.67 (t, CH2 proton). 13C NMR (CDCl3, 400 MHz): δ 208.09 (C=O), (aromatic ipso carbon atoms), 115.84–115.51 (aromatic carbon atoms), 55.77 (C-3 carbon), 66.34 (C-2 carbon), 61.09 (C-6 carbon), 51.41 (C-5 carbon), 28.06 (methyl­ene carbon), 43.45 (CH2Cl Carbon). Melting point: 375 K.

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 3[link]. The N1-bound H atoms in both mol­ecules were located in a difference-Fourier map and their coordinates and displacement parameters freely refined. All C-bound H atoms were refined using a riding model with d(C—H) = 0.93 Å for aromatic, 0.97 Å for methyl­ene and 0.98 Å for methine H atoms, all with Uiso = 1.2Ueq (C)

Table 3
Experimental details

  (I) (II)
Crystal data
Chemical formula C19H20ClNO C19H18ClF2NO
Mr 313.81 349.79
Crystal system, space group Monoclinic, P21/c Monoclinic, P21/c
Temperature (K) 293 293
a, b, c (Å) 11.3306 (3), 13.3638 (4), 10.9821 (3) 5.5105 (2), 24.2612 (6), 12.8622 (3)
β (°) 91.996 (2) 93.809 (3)
V3) 1661.90 (8) 1715.77 (9)
Z 4 4
Radiation type Cu Kα Cu Kα
μ (mm−1) 2.03 2.20
Crystal size (mm) 0.42 × 0.38 × 0.14 0.34 × 0.16 × 0.14
 
Data collection
Diffractometer Rigaku Oxford Diffraction Rigaku Oxford Diffraction
Absorption correction Multi-scan (CrysAlis PRO; Rigaku OD, 2015[Rigaku OD (2015). CrysAlis PRO. Rigaku Americas, The Woodlands, Texas, USA.]) Multi-scan (CrysAlis PRO; Rigaku OD, 2015[Rigaku OD (2015). CrysAlis PRO. Rigaku Americas, The Woodlands, Texas, USA.])
Tmin, Tmax 0.535, 1.000 0.524, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections 6237, 3168, 2545 6548, 3267, 2702
Rint 0.028 0.020
(sin θ/λ)max−1) 0.615 0.614
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.055, 0.158, 1.05 0.046, 0.131, 1.04
No. of reflections 3168 3267
No. of parameters 204 222
H-atom treatment H atoms treated by a mixture of independent and constrained refinement H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3) 0.56, −0.44 0.34, −0.38
Computer programs: CrysAlis PRO (Rigaku OD, 2015[Rigaku OD (2015). CrysAlis PRO. Rigaku Americas, The Woodlands, Texas, USA.]), SHELXT (Sheldrick, 2015a[Sheldrick, G. M. (2015a). Acta Cryst. A71, 3-8.]), SHELXL2018 (Sheldrick, 2015b[Sheldrick, G. M. (2015b). Acta Cryst. C71, 3-8.]) and OLEX2 (Dolomanov et al., 2009[Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339-341.]).

Supporting information


Computing details top

For both structures, data collection: CrysAlis PRO (Rigaku OD, 2015); cell refinement: CrysAlis PRO (Rigaku OD, 2015); data reduction: CrysAlis PRO (Rigaku OD, 2015); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2018 (Sheldrick, 2015b); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

3-(2-Chloroethyl)-r-2,c-6-diphenylpiperidin-4-one (I) top
Crystal data top
C19H20ClNOF(000) = 664
Mr = 313.81Dx = 1.254 Mg m3
Monoclinic, P21/cCu Kα radiation, λ = 1.54184 Å
a = 11.3306 (3) ÅCell parameters from 2185 reflections
b = 13.3638 (4) Åθ = 5.1–71.2°
c = 10.9821 (3) ŵ = 2.03 mm1
β = 91.996 (2)°T = 293 K
V = 1661.90 (8) Å3Prism, colourless
Z = 40.42 × 0.38 × 0.14 mm
Data collection top
Rigaku Oxford Diffraction
diffractometer
3168 independent reflections
Radiation source: fine-focus sealed X-ray tube, Enhance (Cu) X-ray Source2545 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.028
Detector resolution: 16.0416 pixels mm-1θmax = 71.4°, θmin = 3.9°
ω scansh = 1313
Absorption correction: multi-scan
(CrysAlis PRO; Rigaku OD, 2015)
k = 1416
Tmin = 0.535, Tmax = 1.000l = 138
6237 measured reflections
Refinement top
Refinement on F2Hydrogen site location: mixed
Least-squares matrix: fullH atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.055 w = 1/[σ2(Fo2) + (0.075P)2 + 0.5181P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.158(Δ/σ)max < 0.001
S = 1.05Δρmax = 0.56 e Å3
3168 reflectionsΔρmin = 0.44 e Å3
204 parametersExtinction correction: SHELXL2018 (Sheldrick, 2015b), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraintsExtinction coefficient: 0.0026 (4)
Primary atom site location: dual
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cl10.08089 (8)0.50912 (12)0.17386 (10)0.1402 (6)
O10.44751 (18)0.41543 (13)0.1217 (2)0.0771 (6)
N10.48661 (13)0.69143 (12)0.26049 (15)0.0370 (4)
H10.511 (2)0.7523 (19)0.270 (2)0.045 (6)*
C10.41112 (15)0.67867 (13)0.15013 (17)0.0356 (4)
H1A0.4604370.6822510.0786970.043*
C20.35356 (16)0.57351 (14)0.15481 (18)0.0393 (4)
H20.3036540.5727340.2259150.047*
C30.44765 (19)0.49404 (15)0.1762 (2)0.0479 (5)
C40.5424 (2)0.51707 (15)0.2711 (2)0.0509 (5)
H4A0.6072570.4704010.2629370.061*
H4B0.5110360.5081400.3514120.061*
C50.58905 (17)0.62451 (15)0.25931 (18)0.0410 (4)
H50.6270330.6313180.1809230.049*
C60.67816 (17)0.64909 (15)0.3605 (2)0.0447 (5)
C70.79567 (19)0.66364 (18)0.3344 (2)0.0557 (6)
H70.8190780.6611120.2541030.067*
C80.8789 (2)0.6821 (2)0.4283 (3)0.0711 (8)
H80.9576340.6919060.4101330.085*
C90.8460 (2)0.6858 (2)0.5464 (3)0.0744 (8)
H90.9020380.6979680.6085080.089*
C100.7293 (3)0.6715 (2)0.5735 (3)0.0688 (7)
H100.7065580.6739520.6540000.083*
C110.6462 (2)0.65346 (19)0.4813 (2)0.0575 (6)
H110.5676190.6441060.5003810.069*
C120.31935 (15)0.76066 (14)0.14123 (16)0.0361 (4)
C130.30967 (17)0.82110 (15)0.03920 (18)0.0420 (4)
H130.3620400.8128530.0233730.050*
C140.2224 (2)0.89410 (17)0.0292 (2)0.0514 (5)
H140.2166070.9339730.0401380.062*
C150.14510 (19)0.90767 (17)0.1206 (2)0.0544 (6)
H150.0865040.9562500.1134380.065*
C160.1547 (2)0.84889 (19)0.2234 (2)0.0574 (6)
H160.1029230.8583680.2862590.069*
C170.24084 (19)0.77582 (18)0.23368 (19)0.0488 (5)
H170.2462490.7363570.3034020.059*
C180.2733 (2)0.55077 (18)0.0436 (2)0.0510 (5)
H18A0.2321580.6116770.0195670.061*
H18B0.3222250.5313140.0231660.061*
C190.1841 (3)0.4707 (3)0.0620 (4)0.0939 (11)
H19A0.2237020.4098280.0888790.113*
H19B0.1421070.4567750.0146240.113*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0686 (5)0.2364 (16)0.1155 (8)0.0747 (8)0.0010 (5)0.0298 (8)
O10.0723 (12)0.0455 (10)0.1114 (15)0.0094 (8)0.0271 (11)0.0258 (10)
N10.0310 (7)0.0311 (8)0.0486 (9)0.0021 (6)0.0054 (6)0.0010 (6)
C10.0295 (8)0.0354 (9)0.0419 (9)0.0005 (7)0.0004 (7)0.0006 (7)
C20.0343 (9)0.0368 (10)0.0466 (10)0.0024 (7)0.0015 (7)0.0015 (8)
C30.0436 (11)0.0344 (10)0.0654 (13)0.0010 (8)0.0037 (9)0.0017 (9)
C40.0487 (11)0.0348 (10)0.0681 (14)0.0067 (9)0.0141 (10)0.0006 (9)
C50.0335 (9)0.0378 (10)0.0514 (11)0.0043 (8)0.0042 (8)0.0003 (8)
C60.0351 (9)0.0359 (10)0.0625 (12)0.0061 (8)0.0092 (8)0.0008 (8)
C70.0397 (11)0.0521 (13)0.0747 (15)0.0006 (9)0.0069 (10)0.0069 (11)
C80.0377 (12)0.0649 (16)0.109 (2)0.0009 (11)0.0211 (13)0.0024 (15)
C90.0599 (15)0.0682 (17)0.092 (2)0.0121 (13)0.0366 (14)0.0202 (14)
C100.0685 (16)0.0701 (17)0.0666 (15)0.0199 (13)0.0167 (12)0.0181 (12)
C110.0458 (11)0.0591 (14)0.0669 (14)0.0107 (10)0.0083 (10)0.0125 (11)
C120.0297 (8)0.0354 (9)0.0428 (9)0.0003 (7)0.0044 (7)0.0007 (7)
C130.0375 (9)0.0446 (11)0.0435 (10)0.0029 (8)0.0051 (7)0.0024 (8)
C140.0498 (12)0.0439 (11)0.0592 (12)0.0003 (9)0.0152 (10)0.0090 (9)
C150.0416 (11)0.0439 (12)0.0766 (15)0.0103 (9)0.0150 (10)0.0058 (10)
C160.0446 (11)0.0635 (14)0.0643 (14)0.0154 (11)0.0036 (10)0.0086 (11)
C170.0438 (11)0.0553 (12)0.0474 (11)0.0104 (9)0.0026 (8)0.0054 (9)
C180.0450 (11)0.0517 (12)0.0556 (12)0.0056 (9)0.0084 (9)0.0063 (10)
C190.082 (2)0.078 (2)0.119 (3)0.0299 (17)0.0414 (19)0.0050 (19)
Geometric parameters (Å, º) top
Cl1—C191.801 (4)C8—C91.363 (4)
O1—C31.209 (3)C9—H90.9300
N1—H10.86 (2)C9—C101.379 (4)
N1—C11.469 (2)C10—H100.9300
N1—C51.466 (2)C10—C111.379 (3)
C1—H1A0.9800C11—H110.9300
C1—C21.551 (2)C12—C131.382 (3)
C1—C121.511 (2)C12—C171.388 (3)
C2—H20.9800C13—H130.9300
C2—C31.517 (3)C13—C141.391 (3)
C2—C181.528 (3)C14—H140.9300
C3—C41.502 (3)C14—C151.367 (3)
C4—H4A0.9700C15—H150.9300
C4—H4B0.9700C15—C161.376 (3)
C4—C51.537 (3)C16—H160.9300
C5—H50.9800C16—C171.383 (3)
C5—C61.512 (3)C17—H170.9300
C6—C71.386 (3)C18—H18A0.9700
C6—C111.389 (3)C18—H18B0.9700
C7—H70.9300C18—C191.490 (4)
C7—C81.395 (4)C19—H19A0.9700
C8—H80.9300C19—H19B0.9700
C1—N1—H1112.3 (15)C8—C9—H9120.1
C5—N1—H1109.1 (16)C8—C9—C10119.8 (2)
C5—N1—C1111.13 (15)C10—C9—H9120.1
N1—C1—H1A108.8C9—C10—H10120.0
N1—C1—C2108.14 (15)C9—C10—C11120.1 (3)
N1—C1—C12110.41 (15)C11—C10—H10120.0
C2—C1—H1A108.8C6—C11—H11119.5
C12—C1—H1A108.8C10—C11—C6121.0 (2)
C12—C1—C2111.71 (15)C10—C11—H11119.5
C1—C2—H2106.9C13—C12—C1120.73 (17)
C3—C2—C1110.20 (15)C13—C12—C17118.22 (18)
C3—C2—H2106.9C17—C12—C1121.04 (17)
C3—C2—C18112.34 (17)C12—C13—H13119.7
C18—C2—C1113.15 (17)C12—C13—C14120.66 (19)
C18—C2—H2106.9C14—C13—H13119.7
O1—C3—C2122.9 (2)C13—C14—H14119.8
O1—C3—C4120.7 (2)C15—C14—C13120.5 (2)
C4—C3—C2116.46 (17)C15—C14—H14119.8
C3—C4—H4A109.2C14—C15—H15120.3
C3—C4—H4B109.2C14—C15—C16119.5 (2)
C3—C4—C5111.87 (17)C16—C15—H15120.3
H4A—C4—H4B107.9C15—C16—H16119.8
C5—C4—H4A109.2C15—C16—C17120.4 (2)
C5—C4—H4B109.2C17—C16—H16119.8
N1—C5—C4107.14 (16)C12—C17—H17119.6
N1—C5—H5108.9C16—C17—C12120.8 (2)
N1—C5—C6111.71 (16)C16—C17—H17119.6
C4—C5—H5108.9C2—C18—H18A108.5
C6—C5—C4111.33 (17)C2—C18—H18B108.5
C6—C5—H5108.9H18A—C18—H18B107.5
C7—C6—C5120.0 (2)C19—C18—C2115.0 (2)
C7—C6—C11118.5 (2)C19—C18—H18A108.5
C11—C6—C5121.46 (19)C19—C18—H18B108.5
C6—C7—H7120.0Cl1—C19—H19A109.6
C6—C7—C8120.1 (3)Cl1—C19—H19B109.6
C8—C7—H7120.0C18—C19—Cl1110.3 (2)
C7—C8—H8119.7C18—C19—H19A109.6
C9—C8—C7120.6 (2)C18—C19—H19B109.6
C9—C8—H8119.7H19A—C19—H19B108.1
O1—C3—C4—C5136.1 (2)C4—C5—C6—C1165.2 (3)
N1—C1—C2—C352.8 (2)C5—N1—C1—C268.10 (18)
N1—C1—C2—C18179.46 (16)C5—N1—C1—C12169.41 (15)
N1—C1—C12—C13123.97 (18)C5—C6—C7—C8177.2 (2)
N1—C1—C12—C1757.6 (2)C5—C6—C11—C10177.0 (2)
N1—C5—C6—C7128.3 (2)C6—C7—C8—C90.1 (4)
N1—C5—C6—C1154.5 (3)C7—C6—C11—C100.2 (4)
C1—N1—C5—C467.8 (2)C7—C8—C9—C100.2 (4)
C1—N1—C5—C6170.05 (16)C8—C9—C10—C110.0 (4)
C1—C2—C3—O1137.1 (2)C9—C10—C11—C60.2 (4)
C1—C2—C3—C443.6 (2)C11—C6—C7—C80.1 (3)
C1—C2—C18—C19158.8 (2)C12—C1—C2—C3174.45 (16)
C1—C12—C13—C14177.64 (18)C12—C1—C2—C1858.8 (2)
C1—C12—C17—C16178.0 (2)C12—C13—C14—C150.4 (3)
C2—C1—C12—C13115.65 (19)C13—C12—C17—C160.5 (3)
C2—C1—C12—C1762.8 (2)C13—C14—C15—C160.4 (3)
C2—C3—C4—C544.6 (3)C14—C15—C16—C170.8 (4)
C2—C18—C19—Cl164.5 (3)C15—C16—C17—C120.3 (4)
C3—C2—C18—C1975.6 (3)C17—C12—C13—C140.9 (3)
C3—C4—C5—N153.6 (2)C18—C2—C3—O19.9 (3)
C3—C4—C5—C6176.03 (18)C18—C2—C3—C4170.81 (19)
C4—C5—C6—C7112.0 (2)
Hydrogen-bond geometry (Å, º) top
Cg3 is the centroid of the C12–C17 ring.
D—H···AD—HH···AD···AD—H···A
N1—H1···O1i0.86 (2)2.52 (2)3.335 (2)158 (2)
C4—H4A···Cg3ii0.972.793.665 (2)150
Symmetry codes: (i) x+1, y+1/2, z+1/2; (ii) x+1, y1/2, z+1/2.
3-(2-chloroethyl)-r-2,c-6-bis(4-fluorophenyl)piperidin-4-one (II) top
Crystal data top
C19H18ClF2NOF(000) = 728
Mr = 349.79Dx = 1.354 Mg m3
Monoclinic, P21/cCu Kα radiation, λ = 1.54184 Å
a = 5.5105 (2) ÅCell parameters from 2364 reflections
b = 24.2612 (6) Åθ = 3.4–71.3°
c = 12.8622 (3) ŵ = 2.20 mm1
β = 93.809 (3)°T = 293 K
V = 1715.77 (9) Å3Prism, colourless
Z = 40.34 × 0.16 × 0.14 mm
Data collection top
Rigaku Oxford Diffraction
diffractometer
3267 independent reflections
Radiation source: fine-focus sealed X-ray tube, Enhance (Cu) X-ray Source2702 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.020
Detector resolution: 16.0416 pixels mm-1θmax = 71.3°, θmin = 3.6°
ω scansh = 66
Absorption correction: multi-scan
(CrysAlis PRO; Rigaku OD, 2015)
k = 2916
Tmin = 0.524, Tmax = 1.000l = 1415
6548 measured reflections
Refinement top
Refinement on F2Hydrogen site location: mixed
Least-squares matrix: fullH atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.046 w = 1/[σ2(Fo2) + (0.0592P)2 + 0.5453P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.131(Δ/σ)max < 0.001
S = 1.04Δρmax = 0.34 e Å3
3267 reflectionsΔρmin = 0.38 e Å3
222 parametersExtinction correction: SHELXL2018 (Sheldrick, 2015b), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraintsExtinction coefficient: 0.0058 (5)
Primary atom site location: dual
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cl10.15647 (18)0.46455 (3)0.38176 (8)0.1057 (3)
F10.2069 (3)0.04268 (6)0.63058 (13)0.0854 (5)
F20.6123 (3)0.45967 (6)0.88365 (11)0.0747 (4)
O10.4499 (4)0.29713 (7)0.28005 (11)0.0702 (5)
N10.3190 (3)0.27067 (6)0.57146 (11)0.0396 (4)
H10.366 (4)0.2579 (9)0.6346 (17)0.043 (5)*
C10.3477 (4)0.29649 (8)0.36027 (14)0.0489 (5)
C20.1985 (4)0.24790 (9)0.39147 (14)0.0528 (5)
H2A0.1991440.2194100.3385820.063*
H2B0.0315210.2591630.3986950.063*
C30.3112 (4)0.22560 (7)0.49651 (14)0.0414 (4)
H30.4781760.2137430.4868230.050*
C40.4808 (3)0.31538 (7)0.54325 (13)0.0384 (4)
H40.6398870.2995190.5308460.046*
C50.3752 (4)0.34225 (7)0.44054 (13)0.0431 (4)
H50.2126710.3563460.4523330.052*
C60.5288 (4)0.39034 (8)0.40516 (16)0.0530 (5)
H6A0.5826610.4120910.4656410.064*
H6B0.6724130.3757490.3751480.064*
C70.3962 (5)0.42751 (11)0.3263 (2)0.0737 (7)
H7A0.3290820.4054870.2684050.088*
H7B0.5104040.4534770.2995510.088*
C80.1707 (3)0.17694 (7)0.53451 (13)0.0389 (4)
C90.2447 (4)0.12399 (8)0.51246 (15)0.0462 (4)
H90.3825230.1189310.4755660.055*
C100.1180 (4)0.07832 (8)0.54414 (17)0.0548 (5)
H100.1667490.0428240.5278700.066*
C110.0797 (4)0.08699 (8)0.59972 (16)0.0534 (5)
C120.1588 (4)0.13849 (9)0.62493 (17)0.0552 (5)
H120.2948200.1429670.6632230.066*
C130.0313 (4)0.18376 (8)0.59200 (16)0.0480 (5)
H130.0816840.2190750.6086200.058*
C140.5130 (3)0.35521 (7)0.63374 (13)0.0378 (4)
C150.3388 (4)0.39397 (8)0.65460 (15)0.0488 (5)
H150.1970120.3962560.6113500.059*
C160.3714 (4)0.42936 (8)0.73856 (16)0.0534 (5)
H160.2540410.4555000.7518830.064*
C170.5796 (4)0.42507 (8)0.80138 (15)0.0513 (5)
C180.7540 (4)0.38685 (10)0.78520 (18)0.0628 (6)
H180.8926400.3841550.8302460.075*
C190.7201 (4)0.35205 (9)0.70008 (17)0.0544 (5)
H190.8388160.3261060.6874070.065*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.1146 (7)0.0738 (5)0.1305 (7)0.0231 (4)0.0211 (5)0.0356 (5)
F10.1086 (12)0.0563 (8)0.0919 (11)0.0353 (8)0.0103 (9)0.0197 (7)
F20.1015 (11)0.0585 (8)0.0632 (8)0.0144 (7)0.0006 (7)0.0275 (6)
O10.1093 (14)0.0624 (9)0.0408 (8)0.0254 (9)0.0187 (8)0.0040 (7)
N10.0553 (9)0.0310 (7)0.0325 (7)0.0058 (6)0.0018 (6)0.0019 (6)
C10.0664 (12)0.0454 (10)0.0342 (9)0.0112 (9)0.0015 (8)0.0048 (7)
C20.0737 (13)0.0469 (10)0.0371 (9)0.0191 (10)0.0017 (9)0.0026 (8)
C30.0506 (10)0.0337 (8)0.0401 (9)0.0062 (7)0.0046 (7)0.0015 (7)
C40.0453 (9)0.0328 (8)0.0370 (8)0.0033 (7)0.0019 (7)0.0006 (7)
C50.0549 (10)0.0373 (9)0.0369 (9)0.0093 (8)0.0023 (7)0.0048 (7)
C60.0693 (13)0.0430 (10)0.0472 (10)0.0153 (9)0.0075 (9)0.0045 (8)
C70.101 (2)0.0561 (13)0.0645 (14)0.0090 (13)0.0123 (13)0.0215 (11)
C80.0465 (9)0.0325 (8)0.0372 (8)0.0037 (7)0.0008 (7)0.0006 (6)
C90.0523 (10)0.0370 (9)0.0494 (10)0.0009 (8)0.0038 (8)0.0060 (8)
C100.0726 (14)0.0295 (9)0.0611 (12)0.0003 (9)0.0048 (10)0.0018 (8)
C110.0662 (12)0.0415 (10)0.0514 (11)0.0176 (9)0.0049 (9)0.0103 (8)
C120.0557 (12)0.0545 (12)0.0563 (11)0.0090 (9)0.0105 (9)0.0017 (9)
C130.0539 (11)0.0356 (9)0.0552 (11)0.0002 (8)0.0083 (9)0.0019 (8)
C140.0471 (9)0.0305 (8)0.0356 (8)0.0062 (7)0.0024 (7)0.0009 (6)
C150.0505 (10)0.0478 (10)0.0475 (10)0.0012 (8)0.0016 (8)0.0052 (8)
C160.0641 (12)0.0417 (10)0.0550 (11)0.0037 (9)0.0085 (9)0.0073 (8)
C170.0715 (13)0.0382 (9)0.0443 (10)0.0151 (9)0.0043 (9)0.0097 (8)
C180.0622 (13)0.0659 (14)0.0577 (12)0.0028 (11)0.0159 (10)0.0153 (11)
C190.0557 (11)0.0492 (11)0.0566 (11)0.0074 (9)0.0079 (9)0.0108 (9)
Geometric parameters (Å, º) top
Cl1—C71.785 (3)C7—H7A0.9700
F1—C111.357 (2)C7—H7B0.9700
F2—C171.353 (2)C8—C91.383 (3)
O1—C11.208 (2)C8—C131.386 (3)
N1—H10.89 (2)C9—H90.9300
N1—C31.457 (2)C9—C101.385 (3)
N1—C41.465 (2)C10—H100.9300
C1—C21.507 (3)C10—C111.359 (3)
C1—C51.517 (3)C11—C121.369 (3)
C2—H2A0.9700C12—H120.9300
C2—H2B0.9700C12—C131.385 (3)
C2—C31.547 (3)C13—H130.9300
C3—H30.9800C14—C151.383 (3)
C3—C81.511 (2)C14—C191.381 (3)
C4—H40.9800C15—H150.9300
C4—C51.551 (2)C15—C161.382 (3)
C4—C141.514 (2)C16—H160.9300
C5—H50.9800C16—C171.363 (3)
C5—C61.528 (2)C17—C181.361 (3)
C6—H6A0.9700C18—H180.9300
C6—H6B0.9700C18—C191.385 (3)
C6—C71.509 (3)C19—H190.9300
C3—N1—H1109.6 (14)C6—C7—H7A109.3
C3—N1—C4112.57 (14)C6—C7—H7B109.3
C4—N1—H1109.7 (14)H7A—C7—H7B107.9
O1—C1—C2122.08 (19)C9—C8—C3119.67 (17)
O1—C1—C5122.75 (18)C9—C8—C13118.58 (17)
C2—C1—C5115.02 (16)C13—C8—C3121.75 (16)
C1—C2—H2A110.1C8—C9—H9119.3
C1—C2—H2B110.1C8—C9—C10121.42 (18)
C1—C2—C3108.16 (16)C10—C9—H9119.3
H2A—C2—H2B108.4C9—C10—H10121.0
C3—C2—H2A110.1C11—C10—C9117.93 (18)
C3—C2—H2B110.1C11—C10—H10121.0
N1—C3—C2107.94 (15)F1—C11—C10118.6 (2)
N1—C3—H3108.5F1—C11—C12118.4 (2)
N1—C3—C8111.46 (14)C10—C11—C12123.02 (19)
C2—C3—H3108.5C11—C12—H12120.8
C8—C3—C2111.80 (15)C11—C12—C13118.36 (19)
C8—C3—H3108.5C13—C12—H12120.8
N1—C4—H4108.4C8—C13—H13119.7
N1—C4—C5108.78 (14)C12—C13—C8120.67 (18)
N1—C4—C14108.93 (13)C12—C13—H13119.7
C5—C4—H4108.4C15—C14—C4122.38 (16)
C14—C4—H4108.4C19—C14—C4119.30 (17)
C14—C4—C5113.86 (14)C19—C14—C15118.29 (17)
C1—C5—C4106.67 (15)C14—C15—H15119.4
C1—C5—H5108.0C16—C15—C14121.19 (19)
C1—C5—C6112.85 (16)C16—C15—H15119.4
C4—C5—H5108.0C15—C16—H16120.8
C6—C5—C4112.99 (16)C17—C16—C15118.48 (19)
C6—C5—H5108.0C17—C16—H16120.8
C5—C6—H6A108.8F2—C17—C16118.6 (2)
C5—C6—H6B108.8F2—C17—C18118.92 (19)
H6A—C6—H6B107.7C18—C17—C16122.44 (18)
C7—C6—C5113.76 (19)C17—C18—H18120.8
C7—C6—H6A108.8C17—C18—C19118.5 (2)
C7—C6—H6B108.8C19—C18—H18120.8
Cl1—C7—H7A109.3C14—C19—C18121.1 (2)
Cl1—C7—H7B109.3C14—C19—H19119.4
C6—C7—Cl1111.78 (17)C18—C19—H19119.4
F1—C11—C12—C13178.99 (19)C4—C5—C6—C7162.48 (18)
F2—C17—C18—C19179.3 (2)C4—C14—C15—C16179.14 (18)
O1—C1—C2—C3120.0 (2)C4—C14—C19—C18178.5 (2)
O1—C1—C5—C4120.4 (2)C5—C1—C2—C355.6 (2)
O1—C1—C5—C64.2 (3)C5—C4—C14—C1543.2 (2)
N1—C3—C8—C9144.20 (17)C5—C4—C14—C19138.73 (19)
N1—C3—C8—C1335.4 (2)C5—C6—C7—Cl167.6 (2)
N1—C4—C5—C156.49 (19)C8—C9—C10—C111.3 (3)
N1—C4—C5—C6178.94 (15)C9—C8—C13—C121.2 (3)
N1—C4—C14—C1578.4 (2)C9—C10—C11—F1179.48 (19)
N1—C4—C14—C1999.7 (2)C9—C10—C11—C120.4 (3)
C1—C2—C3—N156.4 (2)C10—C11—C12—C130.1 (3)
C1—C2—C3—C8179.37 (16)C11—C12—C13—C80.3 (3)
C1—C5—C6—C776.4 (2)C13—C8—C9—C101.7 (3)
C2—C1—C5—C455.1 (2)C14—C4—C5—C1178.17 (15)
C2—C1—C5—C6179.78 (18)C14—C4—C5—C657.3 (2)
C2—C3—C8—C994.9 (2)C14—C15—C16—C170.4 (3)
C2—C3—C8—C1385.5 (2)C15—C14—C19—C180.3 (3)
C3—N1—C4—C565.35 (19)C15—C16—C17—F2179.98 (18)
C3—N1—C4—C14170.01 (15)C15—C16—C17—C180.9 (3)
C3—C8—C9—C10178.71 (18)C16—C17—C18—C191.6 (4)
C3—C8—C13—C12179.24 (18)C17—C18—C19—C141.0 (4)
C4—N1—C3—C264.5 (2)C19—C14—C15—C161.0 (3)
C4—N1—C3—C8172.34 (15)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O1i0.89 (2)2.32 (2)3.189 (2)165 (2)
C9—H9···F2ii0.932.613.378 (2)140
C10—H10···F2iii0.932.583.343 (2)139
C12—H12···O1iv0.932.573.412 (3)150
C16—H16···F1v0.932.623.379 (2)139
Symmetry codes: (i) x, y+1/2, z+1/2; (ii) x, y+1/2, z1/2; (iii) x+1, y1/2, z+3/2; (iv) x1, y+1/2, z+1/2; (v) x, y+1/2, z+3/2.
 

Acknowledgements

JPJ acknowledges the NSF–MRI program (grant No. CHE-1039027) for funds to purchase the X-ray diffractometer. The authors would like to acknowledge Annamalai University for recording the NMR spectra and extend their thanks to the Principal, Dr P. Kathirvel, Chairman, Mr R. Sattanathan, and Treasurer, Mr T. Ramalingam, of Thiruvalluvar Arts and Science College for giving permission to carry out research work in the Chemistry Laboratory.

References

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