research communications
of (4-chlorophenyl)(4-methylpiperidin-1-yl)methanone
aPG and Research Department of Physics, Queen Mary's College, Affiliated to University of Madras, Chennai-4, Tamilnadu, India, bDepartment of Chemistry, Madras Christian College, Affiliated to University of Madras, Chennai-59, Tamilnadu, India, cDepartment of Physics, Madras Christian College, Affiliated to University of Madras, Chennai-59, Tamilnadu, India, dPG and Research Department of Physics, Presidency College, Affiliated to University of Madras, Chennai-5, Tamilnadu, India, and eDepartment of Nuclear Physics, University of Madras, Chennai-25, Tamilnadu, India
*Correspondence e-mail: anbu24663@yahoo.co.in
The title compound, C13H16ClNO, contains a methylpiperidine ring in the stable chair conformation. The mean plane of the twisted piperidine ring subtends a dihedral angle of 39.89 (7)° with that of the benzene ring. In the crystal, weak C—H⋯O interactions link the molecules along the a-axis direction to form infinite molecular chains. H⋯H interatomic interactions, C—H⋯O intermolecular interactions and weak dispersive forces stabilize molecular packing and form a supramolecular network, as established by Hirshfeld surface analysis.
Keywords: crystal structure; piperidine; piperidin-1-yl; Hirshfeld surface.
CCDC reference: 1973841
1. Chemical context
The structures of a wide variety of heterocyclic derivatives have been analysed for their pharma-potentiality over the past three decades (Katritzky, 2010). Among them, derivatives of the six-membered heterocyclic base piperidine have proven to be successful pharmacophores. Naturally existing in abundance, of substituted piperidine compounds exhibit a wide range of biological activities (Yunusov & Azimova, 2013). Anti-convulsant (Santucci et al., 1986), anti-tumor, anti-bacterial (Vinaya et al., 2009), anti-viral (Abdel-Aziza et al., 2010), anti-fungal (Rafiq et al., 2013) and plasma triglyceride-lowering (Uto et al., 2010) activities, along with their antagonist activity as anti-HIV-1 agents (Imamura et al., 2005) are deserving of mention. Piperidin-1-yl derivatives have proven vital in the field of neuropsychosis due to their potent biological activity. They act as either central nervous system (CNS) depressants or as stimuli, based on dosage levels (Ramalingan et al., 2004), and also show anti-tubercular (Patel et al., 2011), anti-cancer (Lefranc et al., 2013), anti-tumor (da Silveira et al., 2017) and, in particular, anti-leukemic (Vinaya et al., 2011) activities. One such active piperidin-1-yl derivative is the title compound, (4-chlorophenyl)(4-methyl piperidin-1-yl)methanone.
2. Structural commentary
The molecular structure of the title compound, which features a chlorobenzene ring and a methylpiperidine ring, is shown in Fig. 1. The C—N distances [1.343 (3)–1.462 (3) Å], C=O distance [1.233 (3) Å] and all other primary bond lengths along with bond angles are well within the range reported for similar structures (Prathebha et al., 2015). The ring puckering parameters [q2 = 0.005 (3), q3 = −0.551 (3), QT = 0.551 (3) Å, φ2 = 203 (32)° and θ = 180.0 (3)°] confirm that the piperidine ring adopts a chair conformation. The C1—N1—C6—O1 and O1—C6—C7—C8 torsion angles are −167.4 (2) and 50.7 (3)°, respectively. The C1—C2—C3—C13 torsion angle [177.7 (2)°] reveals the anti-periplanar (+ap) orientation of the methyl group with respect to the piperidine ring.
3. Supramolecular features
In the crystal, weak C11—H11⋯O1 interactions link translation-related molecules (x − 1, y, z), forming chains parallel to the a axis (Table 1, Fig. 2a). Weak C—H⋯π close contacts between H5A and the benzene ring of an adjacent (1 − x, −y, −z) molecule provide linkage between inversion-related (i.e., head-to-tail) chains (Table 1, Fig. 2b). Analysis of the Hirshfeld surface (Spackman et al., 2009) and the associated two-dimensional fingerprint plots (McKinnon et al., 2007) were performed with CrystalExplorer 17 (Turner et al., 2017). Hirshfeld surfaces mapped over dnorm, were generated using TONTO (Jayatilaka et al., 2005) computations with B3LYP/6-31G(d,p) basis sets (Fig. 3). Among the major non-bonding interactions (Fig. 4), H⋯H contacts have the highest percentage contribution of 52.1%, followed by Cl⋯H/H⋯Cl (18.8%), C⋯H/H⋯C (16.3%), O⋯H/H⋯O (10.4%) and C⋯O/O⋯C (1.1%) interactions. The electrostatic and the polarization energies observed among the molecules are compensated by the repulsive components, while the C—H⋯O interactions along with van der Waals dispersive forces contribute to form the supramolecular network.
4. Database survey
The Cambridge Structural Database (version 5.40, Nov. 2018; Groom et al., 2016) includes various structural analogues of substituted piperidin-1-yl compounds, which include EYIXIT (Schmittel et al., 2004), AFETUB (Rao et al., 2007), IJUZAP (Betz et al., 2011), NIPCAS (Prathebha et al., 2013), QUTGOD (Revathi et al., 2015c), NUKDUU (Revathi et al., 2015d), BEBFEW (Mohamooda Sumaya et al., 2017), GUVXAY (Revathi et al., 2015a) and LUPDUX (Revathi et al., 2015b).
5. Synthesis and crystallization
The title compound was synthesized using the published procedure (Revathi et al., 2018) via a Scholten–Boumann condensation reaction (Fig. 5). A homogeneous mixture of the reagent, 4-methylpiperidine (0.04mol) was prepared with 150ml of methyl ethyl ketone in a round-bottomed flask by stirring it at room temperature for a few minutes. Then 0.04mol of triethylamine was added, followed by stirring for 20min. An equal amount of 2-chlorobenzoyl chloride (0.04mol) was then added slowly under constant stirring and the mixture was then refluxed for 3h at room temperature. The precipitate of triethylammonium chloride formed was filtered off and the filtrate was allowed to evaporate to obtain the title compound. The product was then recrystallized three times from chloroform to obtain block-like single crystals of the title compound, m.p. 325K.
6. Refinement
Crystal data, data collection and structure . H atoms were positioned geometrically (C—H = 0.93–0.97 Å) and refined as riding with Uiso(H) = 1.5Ueq(C-methyl) or 1.2Ueq(C) for all other H atoms.
details are summarized in Table 2Supporting information
CCDC reference: 1973841
https://doi.org/10.1107/S2056989020001930/jj2221sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989020001930/jj2221Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989020001930/jj2221Isup3.cml
Data collection: APEX3 (Bruker, 2012); cell
APEX3/SAINT (Bruker, 2012); data reduction: SAINT/XPREP (Bruker, 2012); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015\bbr06); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012), Mercury (Macrae et al., 2020); software used to prepare material for publication: publCIF (Westrip, 2010).C13H16ClNO | Z = 2 |
Mr = 237.72 | F(000) = 252 |
Triclinic, P1 | Dx = 1.270 Mg m−3 |
a = 6.6286 (4) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 8.1569 (5) Å | Cell parameters from 6685 reflections |
c = 12.0061 (8) Å | θ = 2.9–25.1° |
α = 96.803 (3)° | µ = 0.29 mm−1 |
β = 101.506 (3)° | T = 296 K |
γ = 98.511 (3)° | Block, colourless |
V = 621.73 (7) Å3 | 0.25 × 0.20 × 0.15 mm |
Bruker Kappa APEX3 CMOS diffractometer | 1687 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.061 |
ω and φ scan | θmax = 25.1°, θmin = 3.3° |
Absorption correction: multi-scan (SADABS; Bruker, 2012) | h = −7→7 |
Tmin = 0.840, Tmax = 0.842 | k = −9→9 |
11137 measured reflections | l = −14→14 |
2178 independent reflections |
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)] = 0.049 | H-atom parameters constrained |
wR(F2) = 0.144 | w = 1/[σ2(Fo2) + (0.0575P)2 + 0.3053P] where P = (Fo2 + 2Fc2)/3 |
S = 1.05 | (Δ/σ)max < 0.001 |
2178 reflections | Δρmax = 0.18 e Å−3 |
147 parameters | Δρmin = −0.25 e Å−3 |
0 restraints | Extinction correction: SHELXL2014 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.108 (19) |
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. |
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 > 2sigma(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. |
x | y | z | Uiso*/Ueq | ||
Cl1 | 0.24442 (13) | 0.18102 (11) | −0.44227 (6) | 0.0859 (4) | |
O1 | 1.1366 (2) | 0.3558 (2) | −0.04876 (15) | 0.0658 (5) | |
N1 | 0.9452 (3) | 0.2267 (2) | 0.06264 (17) | 0.0550 (5) | |
C1 | 0.7665 (4) | 0.1096 (3) | 0.0775 (2) | 0.0568 (6) | |
H1A | 0.8106 | 0.0055 | 0.0947 | 0.068* | |
H1B | 0.6601 | 0.0848 | 0.0065 | 0.068* | |
C2 | 0.6753 (4) | 0.1832 (3) | 0.1740 (2) | 0.0592 (6) | |
H2A | 0.5635 | 0.1005 | 0.1858 | 0.071* | |
H2B | 0.6158 | 0.2795 | 0.1523 | 0.071* | |
C3 | 0.8399 (4) | 0.2370 (3) | 0.2863 (2) | 0.0627 (7) | |
H3 | 0.8885 | 0.1362 | 0.3104 | 0.075* | |
C4 | 1.0257 (4) | 0.3522 (4) | 0.2649 (2) | 0.0699 (8) | |
H4A | 0.9837 | 0.4571 | 0.2478 | 0.084* | |
H4B | 1.1357 | 0.3770 | 0.3343 | 0.084* | |
C5 | 1.1111 (4) | 0.2761 (4) | 0.1664 (2) | 0.0672 (7) | |
H5A | 1.2220 | 0.3572 | 0.1521 | 0.081* | |
H5B | 1.1696 | 0.1787 | 0.1869 | 0.081* | |
C6 | 0.9693 (3) | 0.2802 (3) | −0.0362 (2) | 0.0511 (6) | |
C7 | 0.7827 (3) | 0.2502 (3) | −0.1352 (2) | 0.0488 (5) | |
C8 | 0.8006 (4) | 0.1799 (3) | −0.2430 (2) | 0.0557 (6) | |
H8 | 0.9259 | 0.1473 | −0.2518 | 0.067* | |
C9 | 0.6368 (4) | 0.1573 (3) | −0.3373 (2) | 0.0609 (7) | |
H9 | 0.6494 | 0.1071 | −0.4087 | 0.073* | |
C10 | 0.4536 (4) | 0.2104 (3) | −0.3242 (2) | 0.0566 (6) | |
C11 | 0.4326 (4) | 0.2848 (3) | −0.2191 (2) | 0.0551 (6) | |
H11 | 0.3092 | 0.3221 | −0.2118 | 0.066* | |
C12 | 0.5960 (3) | 0.3036 (3) | −0.1249 (2) | 0.0521 (6) | |
H12 | 0.5816 | 0.3525 | −0.0535 | 0.062* | |
C13 | 0.7481 (6) | 0.3170 (4) | 0.3813 (3) | 0.0895 (10) | |
H13A | 0.6345 | 0.2386 | 0.3935 | 0.134* | |
H13B | 0.6978 | 0.4156 | 0.3593 | 0.134* | |
H13C | 0.8543 | 0.3475 | 0.4511 | 0.134* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.0826 (6) | 0.1031 (7) | 0.0649 (5) | 0.0208 (4) | 0.0003 (4) | 0.0062 (4) |
O1 | 0.0437 (9) | 0.0777 (12) | 0.0767 (12) | −0.0028 (8) | 0.0272 (8) | 0.0079 (9) |
N1 | 0.0407 (10) | 0.0592 (12) | 0.0636 (12) | −0.0009 (8) | 0.0120 (9) | 0.0143 (9) |
C1 | 0.0479 (13) | 0.0535 (13) | 0.0664 (15) | −0.0048 (10) | 0.0135 (11) | 0.0140 (11) |
C2 | 0.0474 (13) | 0.0637 (15) | 0.0682 (16) | 0.0030 (11) | 0.0162 (11) | 0.0194 (12) |
C3 | 0.0659 (15) | 0.0614 (15) | 0.0615 (15) | 0.0072 (12) | 0.0129 (12) | 0.0197 (12) |
C4 | 0.0630 (16) | 0.0730 (17) | 0.0637 (16) | −0.0050 (13) | −0.0014 (12) | 0.0171 (13) |
C5 | 0.0413 (12) | 0.0772 (18) | 0.0788 (18) | −0.0013 (12) | 0.0037 (12) | 0.0266 (14) |
C6 | 0.0451 (12) | 0.0480 (12) | 0.0637 (14) | 0.0078 (10) | 0.0223 (10) | 0.0046 (10) |
C7 | 0.0457 (12) | 0.0451 (12) | 0.0577 (13) | 0.0025 (9) | 0.0208 (10) | 0.0076 (10) |
C8 | 0.0533 (13) | 0.0574 (14) | 0.0620 (15) | 0.0083 (11) | 0.0280 (12) | 0.0075 (11) |
C9 | 0.0714 (16) | 0.0623 (15) | 0.0521 (14) | 0.0101 (12) | 0.0251 (12) | 0.0033 (11) |
C10 | 0.0596 (14) | 0.0567 (14) | 0.0534 (13) | 0.0056 (11) | 0.0150 (11) | 0.0092 (11) |
C11 | 0.0481 (12) | 0.0586 (14) | 0.0606 (14) | 0.0084 (10) | 0.0172 (11) | 0.0100 (11) |
C12 | 0.0497 (13) | 0.0542 (13) | 0.0545 (13) | 0.0061 (10) | 0.0218 (11) | 0.0037 (10) |
C13 | 0.104 (2) | 0.094 (2) | 0.074 (2) | 0.0115 (19) | 0.0294 (18) | 0.0131 (17) |
Cl1—C10 | 1.740 (3) | C5—H5A | 0.9700 |
O1—C6 | 1.233 (3) | C5—H5B | 0.9700 |
N1—C6 | 1.343 (3) | C6—C7 | 1.502 (3) |
N1—C5 | 1.459 (3) | C7—C8 | 1.388 (3) |
N1—C1 | 1.462 (3) | C7—C12 | 1.394 (3) |
C1—C2 | 1.513 (3) | C8—C9 | 1.377 (3) |
C1—H1A | 0.9700 | C8—H8 | 0.9300 |
C1—H1B | 0.9700 | C9—C10 | 1.379 (4) |
C2—C3 | 1.527 (3) | C9—H9 | 0.9300 |
C2—H2A | 0.9700 | C10—C11 | 1.376 (3) |
C2—H2B | 0.9700 | C11—C12 | 1.378 (3) |
C3—C4 | 1.519 (4) | C11—H11 | 0.9300 |
C3—C13 | 1.522 (4) | C12—H12 | 0.9300 |
C3—H3 | 0.9800 | C13—H13A | 0.9600 |
C4—C5 | 1.517 (4) | C13—H13B | 0.9600 |
C4—H4A | 0.9700 | C13—H13C | 0.9600 |
C4—H4B | 0.9700 | ||
C6—N1—C5 | 120.52 (19) | N1—C5—H5B | 109.6 |
C6—N1—C1 | 125.8 (2) | C4—C5—H5B | 109.6 |
C5—N1—C1 | 113.55 (19) | H5A—C5—H5B | 108.1 |
N1—C1—C2 | 110.72 (19) | O1—C6—N1 | 123.0 (2) |
N1—C1—H1A | 109.5 | O1—C6—C7 | 118.5 (2) |
C2—C1—H1A | 109.5 | N1—C6—C7 | 118.53 (19) |
N1—C1—H1B | 109.5 | C8—C7—C12 | 118.3 (2) |
C2—C1—H1B | 109.5 | C8—C7—C6 | 119.34 (19) |
H1A—C1—H1B | 108.1 | C12—C7—C6 | 122.1 (2) |
C1—C2—C3 | 111.9 (2) | C9—C8—C7 | 121.4 (2) |
C1—C2—H2A | 109.2 | C9—C8—H8 | 119.3 |
C3—C2—H2A | 109.2 | C7—C8—H8 | 119.3 |
C1—C2—H2B | 109.2 | C8—C9—C10 | 118.9 (2) |
C3—C2—H2B | 109.2 | C8—C9—H9 | 120.5 |
H2A—C2—H2B | 107.9 | C10—C9—H9 | 120.5 |
C4—C3—C13 | 112.4 (2) | C11—C10—C9 | 121.2 (2) |
C4—C3—C2 | 109.3 (2) | C11—C10—Cl1 | 119.38 (19) |
C13—C3—C2 | 111.4 (2) | C9—C10—Cl1 | 119.45 (19) |
C4—C3—H3 | 107.9 | C10—C11—C12 | 119.4 (2) |
C13—C3—H3 | 107.9 | C10—C11—H11 | 120.3 |
C2—C3—H3 | 107.9 | C12—C11—H11 | 120.3 |
C5—C4—C3 | 112.6 (2) | C11—C12—C7 | 120.8 (2) |
C5—C4—H4A | 109.1 | C11—C12—H12 | 119.6 |
C3—C4—H4A | 109.1 | C7—C12—H12 | 119.6 |
C5—C4—H4B | 109.1 | C3—C13—H13A | 109.5 |
C3—C4—H4B | 109.1 | C3—C13—H13B | 109.5 |
H4A—C4—H4B | 107.8 | H13A—C13—H13B | 109.5 |
N1—C5—C4 | 110.3 (2) | C3—C13—H13C | 109.5 |
N1—C5—H5A | 109.6 | H13A—C13—H13C | 109.5 |
C4—C5—H5A | 109.6 | H13B—C13—H13C | 109.5 |
C6—N1—C1—C2 | −126.7 (2) | O1—C6—C7—C8 | 50.7 (3) |
C5—N1—C1—C2 | 57.3 (3) | N1—C6—C7—C8 | −130.7 (2) |
N1—C1—C2—C3 | −55.0 (3) | O1—C6—C7—C12 | −123.7 (2) |
C1—C2—C3—C4 | 52.9 (3) | N1—C6—C7—C12 | 54.8 (3) |
C1—C2—C3—C13 | 177.7 (2) | C12—C7—C8—C9 | −2.3 (3) |
C13—C3—C4—C5 | −177.3 (2) | C6—C7—C8—C9 | −176.9 (2) |
C2—C3—C4—C5 | −53.1 (3) | C7—C8—C9—C10 | 1.8 (4) |
C6—N1—C5—C4 | 126.9 (2) | C8—C9—C10—C11 | 0.0 (4) |
C1—N1—C5—C4 | −56.8 (3) | C8—C9—C10—Cl1 | −179.41 (19) |
C3—C4—C5—N1 | 54.8 (3) | C9—C10—C11—C12 | −1.3 (4) |
C5—N1—C6—O1 | 8.4 (4) | Cl1—C10—C11—C12 | 178.09 (18) |
C1—N1—C6—O1 | −167.4 (2) | C10—C11—C12—C7 | 0.8 (3) |
C5—N1—C6—C7 | −170.0 (2) | C8—C7—C12—C11 | 0.9 (3) |
C1—N1—C6—C7 | 14.2 (3) | C6—C7—C12—C11 | 175.4 (2) |
Cg2 is the centroid of the C7–C12 ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
C11—H11···O1i | 0.93 | 2.46 | 3.166 (3) | 132 |
C2—H2A···Cg2ii | 0.97 | 2.95 | 3.843 (3) | 154 |
Symmetry codes: (i) x−1, y, z; (ii) −x+1, −y, −z. |
Surface parameter | Min | Mean | Max |
di (Å) | 1.030 | 1.696 | 2.851 |
de (Å | 1.031 | 1.699 | 2.694 |
dnorm (Å) | -0.176 | 0.537 | 1.463 |
Acknowledgements
The authors thank the Central Instrumentation Facility, DST–FIST, Queen Mary's College, Chennai-4, for the computing facilities and SAIF, IIT, Madras, for the X-ray data collection.
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