research communications
Crystal structures of two new 3-(2-chloroethyl)-r(2),c(6)-diarylpiperidin-4-ones
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
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, 2009, 2011). Most of the 2,6-diaryl-substituted piperidones and their derivatives are of significant pharmacological importance (Aridoss et al., 2007). Some novel 3,5-dichloro-2,6-diarylpiperidin-4-ones are also reported to possess antimicrobial activity (Bhakiaraj et al., 2014). Piperidones also display analgesic, anti-inflammatory, central nervous system (CNS), local anaesthetic, anticancer and antimicrobial activity (Perumal et al., 2001). 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) has reported the 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.
2. Structural commentary
Two new 3-(2-chloroethyl)-r-2,c-6-diarylpiperidin-4-one compounds, C19H20ClNO (I) and C19H18ClF2NO (II), each crystallize in the P21/c with one independent molecule in the The piperidone ring adopts a chair conformation in (I), (Fig. 1), whereas it forms a slightly distorted chair conformation in (II), (Fig. 2), with puckering parameters Q = 0.576 (2) Å, θ = 164.2 (2)°, φ = 179.4 (8)° in (I) and Q = 0.601 (2) Å, θ = 4.93 (19)°, φ = 356 (2)° in (II). The dihedral angle between the mean planes of the phenyl rings is 59.1 (1)° in (I) and 76.1 (1)° in (II). The increase in this dihedral angle in (II) 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) and 331.9° in (II)] is consistent with sp3 (Beddoes et al., 1986).
The substituents on the piperidine ring in both (I) and (II) adopt equatorial orientations with the keto oxygen atom being anti-clinal [O1—C3—C4—C5 = 136.1 (2)°] in (I) and anti-periplanar [O1—C1—C5—C4 = −120.4 (2)°] in (II). The 2-chloroethyl group lies in a syn-clinal orientation in both (I) [C3—C2—C18—C19 = 75.6 (3)°] and (II) [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) whereas in (II) 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), forming infinite C(6) chains along the b-axis direction, with the molecules rotating in a 180° spiral motif along the axis (Table 1, Fig. 3). In addition, a weak C—H⋯π interaction between the piperdine ring and a diaryl group in (I) also occurs.
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In (II), weak N—H⋯O hydrogen bonds (Fig. 4, Table 2) 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) are also observed and contribute to the packing stability. In (II), 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, − y, − + z; centroid of the C8–C13 ring] interaction also between the piperidine ring and a diaryl group is observed.
4. Database survey
A search in the Cambridge Crystallographic Database (CSD version 5.38 of Nov, 2016, updates May, 2017; Groom et al., 2016) 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 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 viz. 2,6-diphenyl-3-isopropylpiperidin-4-one (ACEZUD; Nilofar Nissa et al., 2001) and t-3-pentyl-r-2,c-6-diphenylpiperidin-4-one (RUGLOV; Gayathri et al., 2009) were then compared with the two reported here. The piperidone ring in compounds (I) and (II) 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) and (II), 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) and (II) were obtained after two days. The yield of the isolated product was 3.0 g (I) and 2.5 g (II).
3-(2-Chloroethyl)-r-2,c-6-diphenylpiperidin-4-one, (C19H20ClNO), (I):
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):
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 . 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)
details are summarized in Table 3Supporting information
https://doi.org/10.1107/S2056989018003766/sj5546sup1.cif
contains datablocks I, II, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989018003766/sj5546Isup2.hkl
Structure factors: contains datablock II. DOI: https://doi.org/10.1107/S2056989018003766/sj5546IIsup3.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989018003766/sj5546Isup4.cml
Supporting information file. DOI: https://doi.org/10.1107/S2056989018003766/sj5546IIsup5.cml
For both structures, data collection: CrysAlis PRO (Rigaku OD, 2015); cell
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).C19H20ClNO | F(000) = 664 |
Mr = 313.81 | Dx = 1.254 Mg m−3 |
Monoclinic, P21/c | Cu Kα radiation, λ = 1.54184 Å |
a = 11.3306 (3) Å | Cell parameters from 2185 reflections |
b = 13.3638 (4) Å | θ = 5.1–71.2° |
c = 10.9821 (3) Å | µ = 2.03 mm−1 |
β = 91.996 (2)° | T = 293 K |
V = 1661.90 (8) Å3 | Prism, colourless |
Z = 4 | 0.42 × 0.38 × 0.14 mm |
Rigaku Oxford Diffraction diffractometer | 3168 independent reflections |
Radiation source: fine-focus sealed X-ray tube, Enhance (Cu) X-ray Source | 2545 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.028 |
Detector resolution: 16.0416 pixels mm-1 | θmax = 71.4°, θmin = 3.9° |
ω scans | h = −13→13 |
Absorption correction: multi-scan (CrysAlis PRO; Rigaku OD, 2015) | k = −14→16 |
Tmin = 0.535, Tmax = 1.000 | l = −13→8 |
6237 measured reflections |
Refinement on F2 | Hydrogen site location: mixed |
Least-squares matrix: full | H 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 = 1.05 | Δρmax = 0.56 e Å−3 |
3168 reflections | Δρmin = −0.44 e Å−3 |
204 parameters | Extinction correction: SHELXL2018 (Sheldrick, 2015b), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
0 restraints | Extinction coefficient: 0.0026 (4) |
Primary atom site location: dual |
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. |
x | y | z | Uiso*/Ueq | ||
Cl1 | 0.08089 (8) | 0.50912 (12) | 0.17386 (10) | 0.1402 (6) | |
O1 | 0.44751 (18) | 0.41543 (13) | 0.1217 (2) | 0.0771 (6) | |
N1 | 0.48661 (13) | 0.69143 (12) | 0.26049 (15) | 0.0370 (4) | |
H1 | 0.511 (2) | 0.7523 (19) | 0.270 (2) | 0.045 (6)* | |
C1 | 0.41112 (15) | 0.67867 (13) | 0.15013 (17) | 0.0356 (4) | |
H1A | 0.460437 | 0.682251 | 0.078697 | 0.043* | |
C2 | 0.35356 (16) | 0.57351 (14) | 0.15481 (18) | 0.0393 (4) | |
H2 | 0.303654 | 0.572734 | 0.225915 | 0.047* | |
C3 | 0.44765 (19) | 0.49404 (15) | 0.1762 (2) | 0.0479 (5) | |
C4 | 0.5424 (2) | 0.51707 (15) | 0.2711 (2) | 0.0509 (5) | |
H4A | 0.607257 | 0.470401 | 0.262937 | 0.061* | |
H4B | 0.511036 | 0.508140 | 0.351412 | 0.061* | |
C5 | 0.58905 (17) | 0.62451 (15) | 0.25931 (18) | 0.0410 (4) | |
H5 | 0.627033 | 0.631318 | 0.180923 | 0.049* | |
C6 | 0.67816 (17) | 0.64909 (15) | 0.3605 (2) | 0.0447 (5) | |
C7 | 0.79567 (19) | 0.66364 (18) | 0.3344 (2) | 0.0557 (6) | |
H7 | 0.819078 | 0.661112 | 0.254103 | 0.067* | |
C8 | 0.8789 (2) | 0.6821 (2) | 0.4283 (3) | 0.0711 (8) | |
H8 | 0.957634 | 0.691906 | 0.410133 | 0.085* | |
C9 | 0.8460 (2) | 0.6858 (2) | 0.5464 (3) | 0.0744 (8) | |
H9 | 0.902038 | 0.697968 | 0.608508 | 0.089* | |
C10 | 0.7293 (3) | 0.6715 (2) | 0.5735 (3) | 0.0688 (7) | |
H10 | 0.706558 | 0.673952 | 0.654000 | 0.083* | |
C11 | 0.6462 (2) | 0.65346 (19) | 0.4813 (2) | 0.0575 (6) | |
H11 | 0.567619 | 0.644106 | 0.500381 | 0.069* | |
C12 | 0.31935 (15) | 0.76066 (14) | 0.14123 (16) | 0.0361 (4) | |
C13 | 0.30967 (17) | 0.82110 (15) | 0.03920 (18) | 0.0420 (4) | |
H13 | 0.362040 | 0.812853 | −0.023373 | 0.050* | |
C14 | 0.2224 (2) | 0.89410 (17) | 0.0292 (2) | 0.0514 (5) | |
H14 | 0.216607 | 0.933973 | −0.040138 | 0.062* | |
C15 | 0.14510 (19) | 0.90767 (17) | 0.1206 (2) | 0.0544 (6) | |
H15 | 0.086504 | 0.956250 | 0.113438 | 0.065* | |
C16 | 0.1547 (2) | 0.84889 (19) | 0.2234 (2) | 0.0574 (6) | |
H16 | 0.102923 | 0.858368 | 0.286259 | 0.069* | |
C17 | 0.24084 (19) | 0.77582 (18) | 0.23368 (19) | 0.0488 (5) | |
H17 | 0.246249 | 0.736357 | 0.303402 | 0.059* | |
C18 | 0.2733 (2) | 0.55077 (18) | 0.0436 (2) | 0.0510 (5) | |
H18A | 0.232158 | 0.611677 | 0.019567 | 0.061* | |
H18B | 0.322225 | 0.531314 | −0.023166 | 0.061* | |
C19 | 0.1841 (3) | 0.4707 (3) | 0.0620 (4) | 0.0939 (11) | |
H19A | 0.223702 | 0.409828 | 0.088879 | 0.113* | |
H19B | 0.142107 | 0.456775 | −0.014624 | 0.113* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.0686 (5) | 0.2364 (16) | 0.1155 (8) | −0.0747 (8) | −0.0010 (5) | 0.0298 (8) |
O1 | 0.0723 (12) | 0.0455 (10) | 0.1114 (15) | 0.0094 (8) | −0.0271 (11) | −0.0258 (10) |
N1 | 0.0310 (7) | 0.0311 (8) | 0.0486 (9) | 0.0021 (6) | −0.0054 (6) | −0.0010 (6) |
C1 | 0.0295 (8) | 0.0354 (9) | 0.0419 (9) | 0.0005 (7) | 0.0004 (7) | 0.0006 (7) |
C2 | 0.0343 (9) | 0.0368 (10) | 0.0466 (10) | −0.0024 (7) | −0.0015 (7) | −0.0015 (8) |
C3 | 0.0436 (11) | 0.0344 (10) | 0.0654 (13) | −0.0010 (8) | −0.0037 (9) | −0.0017 (9) |
C4 | 0.0487 (11) | 0.0348 (10) | 0.0681 (14) | 0.0067 (9) | −0.0141 (10) | 0.0006 (9) |
C5 | 0.0335 (9) | 0.0378 (10) | 0.0514 (11) | 0.0043 (8) | −0.0042 (8) | −0.0003 (8) |
C6 | 0.0351 (9) | 0.0359 (10) | 0.0625 (12) | 0.0061 (8) | −0.0092 (8) | −0.0008 (8) |
C7 | 0.0397 (11) | 0.0521 (13) | 0.0747 (15) | 0.0006 (9) | −0.0069 (10) | 0.0069 (11) |
C8 | 0.0377 (12) | 0.0649 (16) | 0.109 (2) | −0.0009 (11) | −0.0211 (13) | 0.0024 (15) |
C9 | 0.0599 (15) | 0.0682 (17) | 0.092 (2) | 0.0121 (13) | −0.0366 (14) | −0.0202 (14) |
C10 | 0.0685 (16) | 0.0701 (17) | 0.0666 (15) | 0.0199 (13) | −0.0167 (12) | −0.0181 (12) |
C11 | 0.0458 (11) | 0.0591 (14) | 0.0669 (14) | 0.0107 (10) | −0.0083 (10) | −0.0125 (11) |
C12 | 0.0297 (8) | 0.0354 (9) | 0.0428 (9) | −0.0003 (7) | −0.0044 (7) | −0.0007 (7) |
C13 | 0.0375 (9) | 0.0446 (11) | 0.0435 (10) | −0.0029 (8) | −0.0051 (7) | 0.0024 (8) |
C14 | 0.0498 (12) | 0.0439 (11) | 0.0592 (12) | 0.0003 (9) | −0.0152 (10) | 0.0090 (9) |
C15 | 0.0416 (11) | 0.0439 (12) | 0.0766 (15) | 0.0103 (9) | −0.0150 (10) | −0.0058 (10) |
C16 | 0.0446 (11) | 0.0635 (14) | 0.0643 (14) | 0.0154 (11) | 0.0036 (10) | −0.0086 (11) |
C17 | 0.0438 (11) | 0.0553 (12) | 0.0474 (11) | 0.0104 (9) | 0.0026 (8) | 0.0054 (9) |
C18 | 0.0450 (11) | 0.0517 (12) | 0.0556 (12) | −0.0056 (9) | −0.0084 (9) | −0.0063 (10) |
C19 | 0.082 (2) | 0.078 (2) | 0.119 (3) | −0.0299 (17) | −0.0414 (19) | 0.0050 (19) |
Cl1—C19 | 1.801 (4) | C8—C9 | 1.363 (4) |
O1—C3 | 1.209 (3) | C9—H9 | 0.9300 |
N1—H1 | 0.86 (2) | C9—C10 | 1.379 (4) |
N1—C1 | 1.469 (2) | C10—H10 | 0.9300 |
N1—C5 | 1.466 (2) | C10—C11 | 1.379 (3) |
C1—H1A | 0.9800 | C11—H11 | 0.9300 |
C1—C2 | 1.551 (2) | C12—C13 | 1.382 (3) |
C1—C12 | 1.511 (2) | C12—C17 | 1.388 (3) |
C2—H2 | 0.9800 | C13—H13 | 0.9300 |
C2—C3 | 1.517 (3) | C13—C14 | 1.391 (3) |
C2—C18 | 1.528 (3) | C14—H14 | 0.9300 |
C3—C4 | 1.502 (3) | C14—C15 | 1.367 (3) |
C4—H4A | 0.9700 | C15—H15 | 0.9300 |
C4—H4B | 0.9700 | C15—C16 | 1.376 (3) |
C4—C5 | 1.537 (3) | C16—H16 | 0.9300 |
C5—H5 | 0.9800 | C16—C17 | 1.383 (3) |
C5—C6 | 1.512 (3) | C17—H17 | 0.9300 |
C6—C7 | 1.386 (3) | C18—H18A | 0.9700 |
C6—C11 | 1.389 (3) | C18—H18B | 0.9700 |
C7—H7 | 0.9300 | C18—C19 | 1.490 (4) |
C7—C8 | 1.395 (4) | C19—H19A | 0.9700 |
C8—H8 | 0.9300 | C19—H19B | 0.9700 |
C1—N1—H1 | 112.3 (15) | C8—C9—H9 | 120.1 |
C5—N1—H1 | 109.1 (16) | C8—C9—C10 | 119.8 (2) |
C5—N1—C1 | 111.13 (15) | C10—C9—H9 | 120.1 |
N1—C1—H1A | 108.8 | C9—C10—H10 | 120.0 |
N1—C1—C2 | 108.14 (15) | C9—C10—C11 | 120.1 (3) |
N1—C1—C12 | 110.41 (15) | C11—C10—H10 | 120.0 |
C2—C1—H1A | 108.8 | C6—C11—H11 | 119.5 |
C12—C1—H1A | 108.8 | C10—C11—C6 | 121.0 (2) |
C12—C1—C2 | 111.71 (15) | C10—C11—H11 | 119.5 |
C1—C2—H2 | 106.9 | C13—C12—C1 | 120.73 (17) |
C3—C2—C1 | 110.20 (15) | C13—C12—C17 | 118.22 (18) |
C3—C2—H2 | 106.9 | C17—C12—C1 | 121.04 (17) |
C3—C2—C18 | 112.34 (17) | C12—C13—H13 | 119.7 |
C18—C2—C1 | 113.15 (17) | C12—C13—C14 | 120.66 (19) |
C18—C2—H2 | 106.9 | C14—C13—H13 | 119.7 |
O1—C3—C2 | 122.9 (2) | C13—C14—H14 | 119.8 |
O1—C3—C4 | 120.7 (2) | C15—C14—C13 | 120.5 (2) |
C4—C3—C2 | 116.46 (17) | C15—C14—H14 | 119.8 |
C3—C4—H4A | 109.2 | C14—C15—H15 | 120.3 |
C3—C4—H4B | 109.2 | C14—C15—C16 | 119.5 (2) |
C3—C4—C5 | 111.87 (17) | C16—C15—H15 | 120.3 |
H4A—C4—H4B | 107.9 | C15—C16—H16 | 119.8 |
C5—C4—H4A | 109.2 | C15—C16—C17 | 120.4 (2) |
C5—C4—H4B | 109.2 | C17—C16—H16 | 119.8 |
N1—C5—C4 | 107.14 (16) | C12—C17—H17 | 119.6 |
N1—C5—H5 | 108.9 | C16—C17—C12 | 120.8 (2) |
N1—C5—C6 | 111.71 (16) | C16—C17—H17 | 119.6 |
C4—C5—H5 | 108.9 | C2—C18—H18A | 108.5 |
C6—C5—C4 | 111.33 (17) | C2—C18—H18B | 108.5 |
C6—C5—H5 | 108.9 | H18A—C18—H18B | 107.5 |
C7—C6—C5 | 120.0 (2) | C19—C18—C2 | 115.0 (2) |
C7—C6—C11 | 118.5 (2) | C19—C18—H18A | 108.5 |
C11—C6—C5 | 121.46 (19) | C19—C18—H18B | 108.5 |
C6—C7—H7 | 120.0 | Cl1—C19—H19A | 109.6 |
C6—C7—C8 | 120.1 (3) | Cl1—C19—H19B | 109.6 |
C8—C7—H7 | 120.0 | C18—C19—Cl1 | 110.3 (2) |
C7—C8—H8 | 119.7 | C18—C19—H19A | 109.6 |
C9—C8—C7 | 120.6 (2) | C18—C19—H19B | 109.6 |
C9—C8—H8 | 119.7 | H19A—C19—H19B | 108.1 |
O1—C3—C4—C5 | 136.1 (2) | C4—C5—C6—C11 | −65.2 (3) |
N1—C1—C2—C3 | −52.8 (2) | C5—N1—C1—C2 | 68.10 (18) |
N1—C1—C2—C18 | −179.46 (16) | C5—N1—C1—C12 | −169.41 (15) |
N1—C1—C12—C13 | 123.97 (18) | C5—C6—C7—C8 | −177.2 (2) |
N1—C1—C12—C17 | −57.6 (2) | C5—C6—C11—C10 | 177.0 (2) |
N1—C5—C6—C7 | −128.3 (2) | C6—C7—C8—C9 | 0.1 (4) |
N1—C5—C6—C11 | 54.5 (3) | C7—C6—C11—C10 | −0.2 (4) |
C1—N1—C5—C4 | −67.8 (2) | C7—C8—C9—C10 | −0.2 (4) |
C1—N1—C5—C6 | 170.05 (16) | C8—C9—C10—C11 | 0.0 (4) |
C1—C2—C3—O1 | −137.1 (2) | C9—C10—C11—C6 | 0.2 (4) |
C1—C2—C3—C4 | 43.6 (2) | C11—C6—C7—C8 | 0.1 (3) |
C1—C2—C18—C19 | −158.8 (2) | C12—C1—C2—C3 | −174.45 (16) |
C1—C12—C13—C14 | 177.64 (18) | C12—C1—C2—C18 | 58.8 (2) |
C1—C12—C17—C16 | −178.0 (2) | C12—C13—C14—C15 | 0.4 (3) |
C2—C1—C12—C13 | −115.65 (19) | C13—C12—C17—C16 | 0.5 (3) |
C2—C1—C12—C17 | 62.8 (2) | C13—C14—C15—C16 | 0.4 (3) |
C2—C3—C4—C5 | −44.6 (3) | C14—C15—C16—C17 | −0.8 (4) |
C2—C18—C19—Cl1 | 64.5 (3) | C15—C16—C17—C12 | 0.3 (4) |
C3—C2—C18—C19 | 75.6 (3) | C17—C12—C13—C14 | −0.9 (3) |
C3—C4—C5—N1 | 53.6 (2) | C18—C2—C3—O1 | −9.9 (3) |
C3—C4—C5—C6 | 176.03 (18) | C18—C2—C3—C4 | 170.81 (19) |
C4—C5—C6—C7 | 112.0 (2) |
Cg3 is the centroid of the C12–C17 ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O1i | 0.86 (2) | 2.52 (2) | 3.335 (2) | 158 (2) |
C4—H4A···Cg3ii | 0.97 | 2.79 | 3.665 (2) | 150 |
Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) −x+1, y−1/2, −z+1/2. |
C19H18ClF2NO | F(000) = 728 |
Mr = 349.79 | Dx = 1.354 Mg m−3 |
Monoclinic, P21/c | Cu Kα radiation, λ = 1.54184 Å |
a = 5.5105 (2) Å | Cell parameters from 2364 reflections |
b = 24.2612 (6) Å | θ = 3.4–71.3° |
c = 12.8622 (3) Å | µ = 2.20 mm−1 |
β = 93.809 (3)° | T = 293 K |
V = 1715.77 (9) Å3 | Prism, colourless |
Z = 4 | 0.34 × 0.16 × 0.14 mm |
Rigaku Oxford Diffraction diffractometer | 3267 independent reflections |
Radiation source: fine-focus sealed X-ray tube, Enhance (Cu) X-ray Source | 2702 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.020 |
Detector resolution: 16.0416 pixels mm-1 | θmax = 71.3°, θmin = 3.6° |
ω scans | h = −6→6 |
Absorption correction: multi-scan (CrysAlis PRO; Rigaku OD, 2015) | k = −29→16 |
Tmin = 0.524, Tmax = 1.000 | l = −14→15 |
6548 measured reflections |
Refinement on F2 | Hydrogen site location: mixed |
Least-squares matrix: full | H 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 = 1.04 | Δρmax = 0.34 e Å−3 |
3267 reflections | Δρmin = −0.38 e Å−3 |
222 parameters | Extinction correction: SHELXL2018 (Sheldrick, 2015b), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
0 restraints | Extinction coefficient: 0.0058 (5) |
Primary atom site location: dual |
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. |
x | y | z | Uiso*/Ueq | ||
Cl1 | 0.15647 (18) | 0.46455 (3) | 0.38176 (8) | 0.1057 (3) | |
F1 | −0.2069 (3) | 0.04268 (6) | 0.63058 (13) | 0.0854 (5) | |
F2 | 0.6123 (3) | 0.45967 (6) | 0.88365 (11) | 0.0747 (4) | |
O1 | 0.4499 (4) | 0.29713 (7) | 0.28005 (11) | 0.0702 (5) | |
N1 | 0.3190 (3) | 0.27067 (6) | 0.57146 (11) | 0.0396 (4) | |
H1 | 0.366 (4) | 0.2579 (9) | 0.6346 (17) | 0.043 (5)* | |
C1 | 0.3477 (4) | 0.29649 (8) | 0.36027 (14) | 0.0489 (5) | |
C2 | 0.1985 (4) | 0.24790 (9) | 0.39147 (14) | 0.0528 (5) | |
H2A | 0.199144 | 0.219410 | 0.338582 | 0.063* | |
H2B | 0.031521 | 0.259163 | 0.398695 | 0.063* | |
C3 | 0.3112 (4) | 0.22560 (7) | 0.49651 (14) | 0.0414 (4) | |
H3 | 0.478176 | 0.213743 | 0.486823 | 0.050* | |
C4 | 0.4808 (3) | 0.31538 (7) | 0.54325 (13) | 0.0384 (4) | |
H4 | 0.639887 | 0.299519 | 0.530846 | 0.046* | |
C5 | 0.3752 (4) | 0.34225 (7) | 0.44054 (13) | 0.0431 (4) | |
H5 | 0.212671 | 0.356346 | 0.452333 | 0.052* | |
C6 | 0.5288 (4) | 0.39034 (8) | 0.40516 (16) | 0.0530 (5) | |
H6A | 0.582661 | 0.412091 | 0.465641 | 0.064* | |
H6B | 0.672413 | 0.375749 | 0.375148 | 0.064* | |
C7 | 0.3962 (5) | 0.42751 (11) | 0.3263 (2) | 0.0737 (7) | |
H7A | 0.329082 | 0.405487 | 0.268405 | 0.088* | |
H7B | 0.510404 | 0.453477 | 0.299551 | 0.088* | |
C8 | 0.1707 (3) | 0.17694 (7) | 0.53451 (13) | 0.0389 (4) | |
C9 | 0.2447 (4) | 0.12399 (8) | 0.51246 (15) | 0.0462 (4) | |
H9 | 0.382523 | 0.118931 | 0.475566 | 0.055* | |
C10 | 0.1180 (4) | 0.07832 (8) | 0.54414 (17) | 0.0548 (5) | |
H10 | 0.166749 | 0.042824 | 0.527870 | 0.066* | |
C11 | −0.0797 (4) | 0.08699 (8) | 0.59972 (16) | 0.0534 (5) | |
C12 | −0.1588 (4) | 0.13849 (9) | 0.62493 (17) | 0.0552 (5) | |
H12 | −0.294820 | 0.142967 | 0.663223 | 0.066* | |
C13 | −0.0313 (4) | 0.18376 (8) | 0.59200 (16) | 0.0480 (5) | |
H13 | −0.081684 | 0.219075 | 0.608620 | 0.058* | |
C14 | 0.5130 (3) | 0.35521 (7) | 0.63374 (13) | 0.0378 (4) | |
C15 | 0.3388 (4) | 0.39397 (8) | 0.65460 (15) | 0.0488 (5) | |
H15 | 0.197012 | 0.396256 | 0.611350 | 0.059* | |
C16 | 0.3714 (4) | 0.42936 (8) | 0.73856 (16) | 0.0534 (5) | |
H16 | 0.254041 | 0.455500 | 0.751883 | 0.064* | |
C17 | 0.5796 (4) | 0.42507 (8) | 0.80138 (15) | 0.0513 (5) | |
C18 | 0.7540 (4) | 0.38685 (10) | 0.78520 (18) | 0.0628 (6) | |
H18 | 0.892640 | 0.384155 | 0.830246 | 0.075* | |
C19 | 0.7201 (4) | 0.35205 (9) | 0.70008 (17) | 0.0544 (5) | |
H19 | 0.838816 | 0.326106 | 0.687407 | 0.065* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.1146 (7) | 0.0738 (5) | 0.1305 (7) | 0.0231 (4) | 0.0211 (5) | 0.0356 (5) |
F1 | 0.1086 (12) | 0.0563 (8) | 0.0919 (11) | −0.0353 (8) | 0.0103 (9) | 0.0197 (7) |
F2 | 0.1015 (11) | 0.0585 (8) | 0.0632 (8) | −0.0144 (7) | −0.0006 (7) | −0.0275 (6) |
O1 | 0.1093 (14) | 0.0624 (9) | 0.0408 (8) | −0.0254 (9) | 0.0187 (8) | −0.0040 (7) |
N1 | 0.0553 (9) | 0.0310 (7) | 0.0325 (7) | −0.0058 (6) | 0.0018 (6) | 0.0019 (6) |
C1 | 0.0664 (12) | 0.0454 (10) | 0.0342 (9) | −0.0112 (9) | −0.0015 (8) | 0.0048 (7) |
C2 | 0.0737 (13) | 0.0469 (10) | 0.0371 (9) | −0.0191 (10) | −0.0017 (9) | −0.0026 (8) |
C3 | 0.0506 (10) | 0.0337 (8) | 0.0401 (9) | −0.0062 (7) | 0.0046 (7) | −0.0015 (7) |
C4 | 0.0453 (9) | 0.0328 (8) | 0.0370 (8) | −0.0033 (7) | 0.0019 (7) | −0.0006 (7) |
C5 | 0.0549 (10) | 0.0373 (9) | 0.0369 (9) | −0.0093 (8) | 0.0023 (7) | 0.0048 (7) |
C6 | 0.0693 (13) | 0.0430 (10) | 0.0472 (10) | −0.0153 (9) | 0.0075 (9) | 0.0045 (8) |
C7 | 0.101 (2) | 0.0561 (13) | 0.0645 (14) | −0.0090 (13) | 0.0123 (13) | 0.0215 (11) |
C8 | 0.0465 (9) | 0.0325 (8) | 0.0372 (8) | −0.0037 (7) | −0.0008 (7) | −0.0006 (6) |
C9 | 0.0523 (10) | 0.0370 (9) | 0.0494 (10) | −0.0009 (8) | 0.0038 (8) | −0.0060 (8) |
C10 | 0.0726 (14) | 0.0295 (9) | 0.0611 (12) | −0.0003 (9) | −0.0048 (10) | −0.0018 (8) |
C11 | 0.0662 (12) | 0.0415 (10) | 0.0514 (11) | −0.0176 (9) | −0.0049 (9) | 0.0103 (8) |
C12 | 0.0557 (12) | 0.0545 (12) | 0.0563 (11) | −0.0090 (9) | 0.0105 (9) | 0.0017 (9) |
C13 | 0.0539 (11) | 0.0356 (9) | 0.0552 (11) | 0.0002 (8) | 0.0083 (9) | −0.0019 (8) |
C14 | 0.0471 (9) | 0.0305 (8) | 0.0356 (8) | −0.0062 (7) | 0.0024 (7) | 0.0009 (6) |
C15 | 0.0505 (10) | 0.0478 (10) | 0.0475 (10) | 0.0012 (8) | −0.0016 (8) | −0.0052 (8) |
C16 | 0.0641 (12) | 0.0417 (10) | 0.0550 (11) | 0.0037 (9) | 0.0085 (9) | −0.0073 (8) |
C17 | 0.0715 (13) | 0.0382 (9) | 0.0443 (10) | −0.0151 (9) | 0.0043 (9) | −0.0097 (8) |
C18 | 0.0622 (13) | 0.0659 (14) | 0.0577 (12) | −0.0028 (11) | −0.0159 (10) | −0.0153 (11) |
C19 | 0.0557 (11) | 0.0492 (11) | 0.0566 (11) | 0.0074 (9) | −0.0079 (9) | −0.0108 (9) |
Cl1—C7 | 1.785 (3) | C7—H7A | 0.9700 |
F1—C11 | 1.357 (2) | C7—H7B | 0.9700 |
F2—C17 | 1.353 (2) | C8—C9 | 1.383 (3) |
O1—C1 | 1.208 (2) | C8—C13 | 1.386 (3) |
N1—H1 | 0.89 (2) | C9—H9 | 0.9300 |
N1—C3 | 1.457 (2) | C9—C10 | 1.385 (3) |
N1—C4 | 1.465 (2) | C10—H10 | 0.9300 |
C1—C2 | 1.507 (3) | C10—C11 | 1.359 (3) |
C1—C5 | 1.517 (3) | C11—C12 | 1.369 (3) |
C2—H2A | 0.9700 | C12—H12 | 0.9300 |
C2—H2B | 0.9700 | C12—C13 | 1.385 (3) |
C2—C3 | 1.547 (3) | C13—H13 | 0.9300 |
C3—H3 | 0.9800 | C14—C15 | 1.383 (3) |
C3—C8 | 1.511 (2) | C14—C19 | 1.381 (3) |
C4—H4 | 0.9800 | C15—H15 | 0.9300 |
C4—C5 | 1.551 (2) | C15—C16 | 1.382 (3) |
C4—C14 | 1.514 (2) | C16—H16 | 0.9300 |
C5—H5 | 0.9800 | C16—C17 | 1.363 (3) |
C5—C6 | 1.528 (2) | C17—C18 | 1.361 (3) |
C6—H6A | 0.9700 | C18—H18 | 0.9300 |
C6—H6B | 0.9700 | C18—C19 | 1.385 (3) |
C6—C7 | 1.509 (3) | C19—H19 | 0.9300 |
C3—N1—H1 | 109.6 (14) | C6—C7—H7A | 109.3 |
C3—N1—C4 | 112.57 (14) | C6—C7—H7B | 109.3 |
C4—N1—H1 | 109.7 (14) | H7A—C7—H7B | 107.9 |
O1—C1—C2 | 122.08 (19) | C9—C8—C3 | 119.67 (17) |
O1—C1—C5 | 122.75 (18) | C9—C8—C13 | 118.58 (17) |
C2—C1—C5 | 115.02 (16) | C13—C8—C3 | 121.75 (16) |
C1—C2—H2A | 110.1 | C8—C9—H9 | 119.3 |
C1—C2—H2B | 110.1 | C8—C9—C10 | 121.42 (18) |
C1—C2—C3 | 108.16 (16) | C10—C9—H9 | 119.3 |
H2A—C2—H2B | 108.4 | C9—C10—H10 | 121.0 |
C3—C2—H2A | 110.1 | C11—C10—C9 | 117.93 (18) |
C3—C2—H2B | 110.1 | C11—C10—H10 | 121.0 |
N1—C3—C2 | 107.94 (15) | F1—C11—C10 | 118.6 (2) |
N1—C3—H3 | 108.5 | F1—C11—C12 | 118.4 (2) |
N1—C3—C8 | 111.46 (14) | C10—C11—C12 | 123.02 (19) |
C2—C3—H3 | 108.5 | C11—C12—H12 | 120.8 |
C8—C3—C2 | 111.80 (15) | C11—C12—C13 | 118.36 (19) |
C8—C3—H3 | 108.5 | C13—C12—H12 | 120.8 |
N1—C4—H4 | 108.4 | C8—C13—H13 | 119.7 |
N1—C4—C5 | 108.78 (14) | C12—C13—C8 | 120.67 (18) |
N1—C4—C14 | 108.93 (13) | C12—C13—H13 | 119.7 |
C5—C4—H4 | 108.4 | C15—C14—C4 | 122.38 (16) |
C14—C4—H4 | 108.4 | C19—C14—C4 | 119.30 (17) |
C14—C4—C5 | 113.86 (14) | C19—C14—C15 | 118.29 (17) |
C1—C5—C4 | 106.67 (15) | C14—C15—H15 | 119.4 |
C1—C5—H5 | 108.0 | C16—C15—C14 | 121.19 (19) |
C1—C5—C6 | 112.85 (16) | C16—C15—H15 | 119.4 |
C4—C5—H5 | 108.0 | C15—C16—H16 | 120.8 |
C6—C5—C4 | 112.99 (16) | C17—C16—C15 | 118.48 (19) |
C6—C5—H5 | 108.0 | C17—C16—H16 | 120.8 |
C5—C6—H6A | 108.8 | F2—C17—C16 | 118.6 (2) |
C5—C6—H6B | 108.8 | F2—C17—C18 | 118.92 (19) |
H6A—C6—H6B | 107.7 | C18—C17—C16 | 122.44 (18) |
C7—C6—C5 | 113.76 (19) | C17—C18—H18 | 120.8 |
C7—C6—H6A | 108.8 | C17—C18—C19 | 118.5 (2) |
C7—C6—H6B | 108.8 | C19—C18—H18 | 120.8 |
Cl1—C7—H7A | 109.3 | C14—C19—C18 | 121.1 (2) |
Cl1—C7—H7B | 109.3 | C14—C19—H19 | 119.4 |
C6—C7—Cl1 | 111.78 (17) | C18—C19—H19 | 119.4 |
F1—C11—C12—C13 | −178.99 (19) | C4—C5—C6—C7 | −162.48 (18) |
F2—C17—C18—C19 | −179.3 (2) | C4—C14—C15—C16 | 179.14 (18) |
O1—C1—C2—C3 | 120.0 (2) | C4—C14—C19—C18 | −178.5 (2) |
O1—C1—C5—C4 | −120.4 (2) | C5—C1—C2—C3 | −55.6 (2) |
O1—C1—C5—C6 | 4.2 (3) | C5—C4—C14—C15 | 43.2 (2) |
N1—C3—C8—C9 | −144.20 (17) | C5—C4—C14—C19 | −138.73 (19) |
N1—C3—C8—C13 | 35.4 (2) | C5—C6—C7—Cl1 | 67.6 (2) |
N1—C4—C5—C1 | −56.49 (19) | C8—C9—C10—C11 | −1.3 (3) |
N1—C4—C5—C6 | 178.94 (15) | C9—C8—C13—C12 | −1.2 (3) |
N1—C4—C14—C15 | −78.4 (2) | C9—C10—C11—F1 | 179.48 (19) |
N1—C4—C14—C19 | 99.7 (2) | C9—C10—C11—C12 | 0.4 (3) |
C1—C2—C3—N1 | 56.4 (2) | C10—C11—C12—C13 | 0.1 (3) |
C1—C2—C3—C8 | 179.37 (16) | C11—C12—C13—C8 | 0.3 (3) |
C1—C5—C6—C7 | 76.4 (2) | C13—C8—C9—C10 | 1.7 (3) |
C2—C1—C5—C4 | 55.1 (2) | C14—C4—C5—C1 | −178.17 (15) |
C2—C1—C5—C6 | 179.78 (18) | C14—C4—C5—C6 | 57.3 (2) |
C2—C3—C8—C9 | 94.9 (2) | C14—C15—C16—C17 | −0.4 (3) |
C2—C3—C8—C13 | −85.5 (2) | C15—C14—C19—C18 | −0.3 (3) |
C3—N1—C4—C5 | 65.35 (19) | C15—C16—C17—F2 | 179.98 (18) |
C3—N1—C4—C14 | −170.01 (15) | C15—C16—C17—C18 | −0.9 (3) |
C3—C8—C9—C10 | −178.71 (18) | C16—C17—C18—C19 | 1.6 (4) |
C3—C8—C13—C12 | 179.24 (18) | C17—C18—C19—C14 | −1.0 (4) |
C4—N1—C3—C2 | −64.5 (2) | C19—C14—C15—C16 | 1.0 (3) |
C4—N1—C3—C8 | 172.34 (15) |
D—H···A | D—H | H···A | D···A | 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+1/2, z+1/2; (ii) x, −y+1/2, z−1/2; (iii) −x+1, y−1/2, −z+3/2; (iv) x−1, −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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