research communications
Crystal structures of 3,5-bis[(E)-3-hydroxybenzylidene]-1-methylpiperidin-4-one and 3,5-bis[(E)-2-chlorobenzylidene]-1-methylpiperidin-4-one
aLaboratory of Organic Synthesis, Department of Chemistry, Faculty of Mathematics and Natural Sciences, Riau University, Pekanbaru 26293, Indonesia, bDepartment of Chemistry, Faculty of Mathematics and Natural Sciences, Padjadjaran University, Jalan Raya Bandung-Sumedang Km 21, Jatinangor 45363, Sumedang, Indonesia, cDepartment of Chemistry, Faculty of Mathematics and Narural Sciences, Padjadjaran University, Jalan Raya Bandung-Sumedang Km 21, Jatinangor 45363, Sumedang, Indonesia, dX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and eDepartment of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia
*Correspondence e-mail: mustaqim@usm.my
The title compounds, C20H19NO3, (1), and C20H17Cl2NO, (2), are the 3-hydroxybenzylidene and 2-chlorobenzylidene derivatives, respectively, of curcumin [systematic name: (1E,6E)-1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione]. The dihedral angles between the benzene rings in each compound are 21.07 (6)° for (1) and 13.4 (3)° for (2). In both compounds, the piperidinone rings adopt a sofa confirmation and the methyl group attached to the N atom is in an equatorial position. In the crystal of (1), two pairs of O—H⋯N and O—H⋯O hydrogen bonds link the molecules, forming chains along [10-1]. The chains are linked via C—H⋯O hydrogen bonds, forming undulating sheets parallel to the ac plane. In the crystal of (2), molecules are linked by weak C—H⋯Cl hydrogen bonds, forming chains along the [204] direction. The chains are linked along the a-axis direction by π–π interactions [inter-centroid distance = 3.779 (4) Å]. For compound (2), the crystal studied was a non-merohedral twin with the refined ratio of the twin components being 0.116 (6):0.886 (6).
1. Chemical context
Curcumin (diferuloylmethane) is a naturally occurring biologically active compound, isolated from the root of the tumeric plant (Curcuma longa) (Dandia et al., 2012). It has been shown to exhibit anti-oxidant (Rostom et al., 2009), anti-inflammatory (Suzuki et al., 2005), antiviral (Kumar et al., 2007) and antibacterial (Bandgar et al., 2012) activities, and thus has potential against various malignant cancers, diabetes, allergies, arthritis and other chronic illnesses (Yadav et al., 2010; Reddy et al., 2009; Aggarwal et al., 2003; Insuasty et al., 2013; Wu et al., 2013). For the purpose of finding new derivatives with increased systemic bioavailability and enhanced pharmacological activity (Zhao et al., 2010), chemical modifications as well as the synthesis of curcumin analogues have been attempted by many research groups in order to find a better treatment for various diseases (Siddiqui et al., 2006; Gregory et al., 2013). Analogous compounds to (E)-3,5-bis(benzylidene)-4-piperidones present noteworthy cytotoxic activity against leukemia cell lines and colon cancer, among others (Gregory et al., 2013). Different substituents were designed to investigate and discuss the structure–activity relationship (Insuasty et al., 2013). Herein, we report on the synthesis, characterization and crystal structures of two mono-carbonyl analogues of curcumin, namely N-methyl-(3E,5E)-3,5-bis(3-hydroxybenzylidene)-4-piperidone (1) and N-methyl-(3E,5E)-3,5-bis(2-chlorobenzylidene)-4-piperidone (2).
2. Structural commentary
The molecular structures of compounds (1) and (2) are shown in Figs. 1 and 2, respectively. Compound (1) crystallized in the triclinic P (Z = 2), while compound (2) crystallized in the monoclinic P21/n (Z = 4).
The benzene rings (C1–C6 and C14–C19) are inclined to one another by 21.07 (6)° in (1) and by 13.4 (3)° in (2). Both compounds exhibit E conformations about the C7=C8 and C13=C10 bonds. In both compounds, the piperidinone ring (N1/C8–C12) adopts a sofa conformation with atom N1 displaced from the mean plane through the five C atoms (C8–C12) by 0.7052 (10) Å in (1) and 0.705 (5) Å in (2). The puckering parameters for the piperidinone ring conformation in (1) are Q = 0.5280 (12) Å, θ = 55.17 (14)° and φ = 353.08 (17)°, while for (2) they are Q = 0.526 (6) Å, θ = 126.1 (7)° and φ = 182.8 (8)°. In both compounds the methyl group attached to atom N1 is in an equatorial position on the piperidinone ring.
3. Supramolecular features
In the crystal of compound (1), molecules are linked via pairs of O—H⋯N hydrogen bonds, forming inversion dimers enclosing an R22(18) ring motif (Table 1 and Fig. 3). These dimers are linked by pairs of O—H⋯O hydrogen bonds, enclosing an R22(18) ring motif, forming chains along [10] (Table 1 and Fig. 4). The chains are linked via pairs of C—H⋯O hydrogen bonds (Table 1 and Fig. 4), forming undulating sheets lying parallel to the ac plane (Fig. 5).
In the crystal of compound (2), molecules are linked by a weak C4—H4A⋯Cl2i hydrogen bond, forming zigzag chains along [204] (Table 2 and Fig. 6). The chains are linked along the a-axis direction by π–π interactions [Cg2⋯Cg3i = 3.779 (4) Å, where Cg2 and Cg3 are the centroids of rings C1–C6 and C14–C19, respectively; symmetry code: (i) − x + 1, −y, −z].
4. Database survey
A search of the Cambridge Structural Database (CSD, Version 5.36, last update February 2015; Groom & Allen, 2014) of (3E,5E)-3,5-dibenzylidene-1-methylpiperidin-4-one gave 49 hits. One compound, 3,5-bis(4-chlorobenzylidene)-1-methylpiperidin-4-one, is the 4-chlorobenzylidene isomer of compound (2) (UNOXOL; Nesterov et al., 2011). Here, the benzene rings are inclined to one another by 7.58 (8)°, compared to 21.07 (6)° in (1) and 13.4 (3)° in (2). The piperidinone ring also adopts a sofa conformation with the N atom displaced from the mean plane of the five C atoms by 0.7714 (15) Å, compared to 0.7052 (10) Å in (1) and 0.705 (5) Å in (2).
5. Synthesis and crystallization
Both compounds were synthesized according to a partially modified procedure of a previous report (Gregory et al., 2013).
Compound (1): The corresponding N-methyl-4-piperidone (0.99 g, 0.01 mol), 3-hydroxybenzaldehyde (2.23 g, 0.02 mol), 40% aq. NaOH (0.7 ml) and 95% EtOH (5 ml) were mixed with stirring at room temperature for 30 min. The reaction mixture was subjected to microwave irradiation for 3 min at a power of 180 W and temperature of 333 K. The reaction product was cooled and cold water was added. The precipitate formed was filtered and recrystallized from a mixture of n-hexane–ethyl acetate to afford dark yellowish crystals of compound (1) (yield: 3.4 g, 34.5%; m.p. 409–410 K). Rf = 0.43 (n-hexane:EtOAc = 1:1). UV (MeOH) λmax: 364 nm (∊ 4,600). IR (KBr) νmax cm−1: 3400, 1658, 1600 and 1504 cm−1. 1H NMR (500 MHz, CDCl3): δ (p.p.m.) 8.04 (2H, s), 7.31 (2H, d, J = 7.5 Hz), 7.26 (2H, t, J = 7.5 Hz), 6.99 (2H, d, J = 8.0 Hz), 6.93 (2H, t, J = 7.5 Hz), 3.72 (4H, s) and 2.41 (3H, s). 13C NMR (125 MHz, CDCl3): δ (p.p.m.) 185.9, 156.6, 133.2, 130.7, 130.5, 130.3, 122.6, 119.4, 115.7, 57.2, 45.2. HR–ESI–TOFMS: calculated for C20H19NO3 [M + H]+, m/z 321.1365, found m/z 322.1434.
Compound (2): The corresponding N-methyl-4-piperidone (0.98 g, 0.01 mol), 2-chlorobenzaldehyde (2.20 g, 0.02 mol), 40% aq. NaOH (0.7 ml) and 95% EtOH (5 ml) was stirred at room temperature for 30 min. The reaction mixture was subjected to microwave irradiation for 3 min at a power of 180 W and temperature of 333 K. The reaction product was cooled and cold water was added. The precipitate formed was filtered and recrystallized from a mixture of n-hexane–ethyl acetate to afford yellowish crystals of compound (2) (yield: 3.8 g, 38.4%; m.p. 408–410 K). Rf = 0.60 (CH2Cl2:MeOH = 9.5:0.5). UV (MeOH) λmax: 309 nm (∊ 4,400). IR (KBr) νmax cm−1: 3328, 1640 cm−1. 1H NMR (500 MHz, CDCl3): δ (p.p.m.) 8.00 (2H, s), 7.46 (2H, dd, J = 8.0, 1.5 Hz), 7.31 (2H, dd, J = 8.0, 1.5 Hz), 7.30 (2H, d, J = 7.5 Hz), 7.24 (2H, dd, J = 7.5, 1.5 Hz), 3.61 (4H, s), 2.37 (3H, s). 13C NMR (125 MHz, CDCl3): δ (p.p.m.) 186.1, 135.2, 134.3, 134.0, 133.6, 130.3, 130.0, 129.9, 126.4, 56.7, 45.5. HR–ESI–TOFMS: calculated for C20H17Cl2NO [M + H]+, m/z 357.0687, found m/z 358.0776.
6. Refinement
Crystal data, data collection and structure . The O-bound H atoms were located in difference Fourier maps and freely refined. The remaining H atoms were positioned geometrically and refined using a riding model: C—H = 0.95–0.99 Å with Uiso(H) = 1.5Ueq(C-methyl) and 1.2Ueq(C) for other H atoms. A rotating group model was applied to the methyl groups. For compound (2) the crystal studied was a non-merohedral twin with a ratio of the twin components of 0.116 (6):0.886 (6).
details are summarized in Table 3
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Supporting information
https://doi.org/10.1107/S2056989015020976/su5232sup1.cif
contains datablocks 1, 2, global. DOI:Structure factors: contains datablock 1. DOI: https://doi.org/10.1107/S2056989015020976/su52321sup4.hkl
Structure factors: contains datablock 2. DOI: https://doi.org/10.1107/S2056989015020976/su52322sup5.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989015020976/su52321sup4.cml
Supporting information file. DOI: https://doi.org/10.1107/S2056989015020976/su52322sup5.cml
For both compounds, data collection: APEX2 (Bruker, 2009); cell
SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS (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), PLATON (Spek, 2009) and publCIF (Westrip, 2010).C20H19NO3 | Z = 2 |
Mr = 321.36 | F(000) = 340 |
Triclinic, P1 | Dx = 1.358 Mg m−3 |
a = 7.4852 (6) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 9.8588 (9) Å | Cell parameters from 3138 reflections |
c = 11.6115 (10) Å | θ = 2.8–32.1° |
α = 111.7924 (17)° | µ = 0.09 mm−1 |
β = 96.7983 (18)° | T = 100 K |
γ = 92.8848 (17)° | Block, orange |
V = 785.90 (12) Å3 | 0.29 × 0.24 × 0.11 mm |
Bruker APEX DUO CCD area-detector diffractometer | 3133 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.021 |
φ and ω scans | θmax = 27.5°, θmin = 1.9° |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | h = −9→9 |
k = −12→12 | |
10462 measured reflections | l = −15→15 |
3562 independent reflections |
Refinement on F2 | 0 restraints |
Least-squares matrix: full | Hydrogen site location: mixed |
R[F2 > 2σ(F2)] = 0.039 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.117 | w = 1/[σ2(Fo2) + (0.0694P)2 + 0.2741P] where P = (Fo2 + 2Fc2)/3 |
S = 1.04 | (Δ/σ)max < 0.001 |
3562 reflections | Δρmax = 0.37 e Å−3 |
226 parameters | Δρmin = −0.21 e Å−3 |
Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K. |
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. |
x | y | z | Uiso*/Ueq | ||
O1 | 1.16705 (13) | −0.33469 (10) | −0.27862 (8) | 0.0217 (2) | |
O2 | 0.78550 (12) | −0.06971 (10) | 0.30379 (9) | 0.0219 (2) | |
O3 | 0.36575 (12) | 0.35383 (10) | 0.81746 (9) | 0.0197 (2) | |
N1 | 1.15110 (13) | 0.28041 (10) | 0.38630 (9) | 0.0139 (2) | |
C1 | 1.36371 (16) | −0.10777 (13) | 0.09923 (11) | 0.0159 (2) | |
H1A | 1.4117 | −0.0550 | 0.1849 | 0.019* | |
C2 | 1.47889 (17) | −0.16263 (13) | 0.01131 (12) | 0.0182 (3) | |
H2A | 1.6059 | −0.1478 | 0.0376 | 0.022* | |
C3 | 1.41151 (17) | −0.23866 (13) | −0.11397 (12) | 0.0184 (3) | |
H3A | 1.4922 | −0.2770 | −0.1728 | 0.022* | |
C4 | 1.22557 (17) | −0.25933 (13) | −0.15432 (11) | 0.0159 (3) | |
C5 | 1.10880 (16) | −0.20577 (12) | −0.06675 (11) | 0.0145 (2) | |
H5A | 0.9819 | −0.2202 | −0.0936 | 0.017* | |
C6 | 1.17643 (16) | −0.13047 (12) | 0.06113 (11) | 0.0137 (2) | |
C7 | 1.04624 (16) | −0.09053 (12) | 0.14976 (11) | 0.0141 (2) | |
H7A | 0.9348 | −0.1514 | 0.1238 | 0.017* | |
C8 | 1.06141 (16) | 0.02010 (12) | 0.26281 (11) | 0.0136 (2) | |
C9 | 0.91333 (16) | 0.02744 (13) | 0.33844 (11) | 0.0152 (2) | |
C10 | 0.92406 (16) | 0.15518 (12) | 0.45975 (11) | 0.0139 (2) | |
C11 | 1.08023 (16) | 0.27250 (12) | 0.49664 (11) | 0.0144 (2) | |
H11A | 1.0401 | 0.3687 | 0.5454 | 0.017* | |
H11B | 1.1779 | 0.2515 | 0.5511 | 0.017* | |
C12 | 1.21650 (16) | 0.13979 (12) | 0.31593 (11) | 0.0148 (2) | |
H12A | 1.3070 | 0.1144 | 0.3721 | 0.018* | |
H12B | 1.2760 | 0.1484 | 0.2468 | 0.018* | |
C13 | 0.78975 (16) | 0.15721 (12) | 0.52792 (11) | 0.0145 (2) | |
H13A | 0.7002 | 0.0755 | 0.4914 | 0.017* | |
C14 | 0.75909 (16) | 0.26419 (12) | 0.64853 (11) | 0.0136 (2) | |
C15 | 0.58209 (16) | 0.25978 (12) | 0.67642 (11) | 0.0143 (2) | |
H15A | 0.4913 | 0.1888 | 0.6179 | 0.017* | |
C16 | 0.53717 (16) | 0.35752 (12) | 0.78829 (11) | 0.0150 (2) | |
C17 | 0.66948 (17) | 0.46108 (13) | 0.87504 (11) | 0.0173 (3) | |
H17A | 0.6396 | 0.5296 | 0.9509 | 0.021* | |
C18 | 0.84563 (17) | 0.46288 (13) | 0.84920 (11) | 0.0165 (3) | |
H18A | 0.9366 | 0.5320 | 0.9093 | 0.020* | |
C19 | 0.89262 (16) | 0.36657 (13) | 0.73795 (11) | 0.0154 (2) | |
H19A | 1.0142 | 0.3699 | 0.7224 | 0.018* | |
C20 | 1.29894 (17) | 0.39929 (13) | 0.42690 (12) | 0.0183 (3) | |
H20A | 1.2574 | 0.4907 | 0.4814 | 0.027* | |
H20B | 1.3364 | 0.4123 | 0.3533 | 0.027* | |
H20C | 1.4017 | 0.3742 | 0.4731 | 0.027* | |
H1O1 | 1.044 (3) | −0.321 (2) | −0.302 (2) | 0.049 (6)* | |
H1O3 | 0.311 (3) | 0.266 (2) | 0.7732 (18) | 0.038 (5)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0232 (5) | 0.0259 (5) | 0.0132 (4) | 0.0063 (4) | 0.0045 (4) | 0.0032 (4) |
O2 | 0.0192 (5) | 0.0202 (4) | 0.0187 (5) | −0.0078 (3) | 0.0065 (4) | −0.0011 (4) |
O3 | 0.0171 (4) | 0.0197 (4) | 0.0178 (5) | −0.0004 (3) | 0.0076 (3) | 0.0008 (4) |
N1 | 0.0144 (5) | 0.0132 (4) | 0.0126 (5) | −0.0025 (4) | 0.0037 (4) | 0.0030 (4) |
C1 | 0.0172 (6) | 0.0146 (5) | 0.0154 (6) | 0.0012 (4) | 0.0019 (4) | 0.0055 (4) |
C2 | 0.0142 (6) | 0.0200 (6) | 0.0225 (6) | 0.0028 (4) | 0.0044 (5) | 0.0100 (5) |
C3 | 0.0185 (6) | 0.0192 (6) | 0.0198 (6) | 0.0053 (5) | 0.0085 (5) | 0.0079 (5) |
C4 | 0.0210 (6) | 0.0139 (5) | 0.0132 (6) | 0.0029 (4) | 0.0044 (5) | 0.0047 (4) |
C5 | 0.0142 (5) | 0.0140 (5) | 0.0157 (6) | 0.0014 (4) | 0.0035 (4) | 0.0058 (4) |
C6 | 0.0158 (6) | 0.0109 (5) | 0.0151 (6) | 0.0014 (4) | 0.0044 (4) | 0.0053 (4) |
C7 | 0.0136 (5) | 0.0147 (5) | 0.0141 (6) | −0.0003 (4) | 0.0021 (4) | 0.0058 (4) |
C8 | 0.0129 (5) | 0.0137 (5) | 0.0142 (6) | 0.0008 (4) | 0.0025 (4) | 0.0053 (4) |
C9 | 0.0147 (6) | 0.0152 (5) | 0.0151 (6) | 0.0001 (4) | 0.0029 (4) | 0.0049 (4) |
C10 | 0.0138 (5) | 0.0141 (5) | 0.0126 (5) | −0.0005 (4) | 0.0015 (4) | 0.0042 (4) |
C11 | 0.0148 (6) | 0.0151 (5) | 0.0116 (5) | −0.0017 (4) | 0.0029 (4) | 0.0031 (4) |
C12 | 0.0137 (5) | 0.0148 (5) | 0.0147 (6) | −0.0007 (4) | 0.0043 (4) | 0.0037 (4) |
C13 | 0.0142 (5) | 0.0140 (5) | 0.0137 (6) | −0.0012 (4) | 0.0014 (4) | 0.0039 (4) |
C14 | 0.0155 (6) | 0.0136 (5) | 0.0124 (5) | 0.0009 (4) | 0.0029 (4) | 0.0056 (4) |
C15 | 0.0153 (6) | 0.0142 (5) | 0.0118 (5) | −0.0013 (4) | 0.0019 (4) | 0.0036 (4) |
C16 | 0.0153 (6) | 0.0151 (5) | 0.0152 (6) | 0.0017 (4) | 0.0045 (4) | 0.0058 (4) |
C17 | 0.0230 (6) | 0.0145 (5) | 0.0130 (6) | 0.0006 (5) | 0.0044 (5) | 0.0035 (4) |
C18 | 0.0191 (6) | 0.0149 (5) | 0.0138 (6) | −0.0036 (4) | −0.0004 (4) | 0.0052 (4) |
C19 | 0.0146 (6) | 0.0175 (5) | 0.0146 (6) | −0.0008 (4) | 0.0022 (4) | 0.0070 (5) |
C20 | 0.0183 (6) | 0.0153 (5) | 0.0188 (6) | −0.0044 (4) | 0.0047 (5) | 0.0039 (5) |
O1—C4 | 1.3596 (15) | C9—C10 | 1.4908 (16) |
O1—H1O1 | 0.96 (2) | C10—C13 | 1.3476 (16) |
O2—C9 | 1.2351 (14) | C10—C11 | 1.5051 (15) |
O3—C16 | 1.3674 (14) | C11—H11A | 0.9900 |
O3—H1O3 | 0.87 (2) | C11—H11B | 0.9900 |
N1—C12 | 1.4668 (15) | C12—H12A | 0.9900 |
N1—C20 | 1.4684 (14) | C12—H12B | 0.9900 |
N1—C11 | 1.4697 (15) | C13—C14 | 1.4595 (16) |
C1—C2 | 1.3868 (17) | C13—H13A | 0.9500 |
C1—C6 | 1.3996 (17) | C14—C15 | 1.4030 (16) |
C1—H1A | 0.9500 | C14—C19 | 1.4038 (16) |
C2—C3 | 1.3824 (18) | C15—C16 | 1.3912 (16) |
C2—H2A | 0.9500 | C15—H15A | 0.9500 |
C3—C4 | 1.3944 (18) | C16—C17 | 1.3915 (17) |
C3—H3A | 0.9500 | C17—C18 | 1.3871 (17) |
C4—C5 | 1.3910 (16) | C17—H17A | 0.9500 |
C5—C6 | 1.4064 (16) | C18—C19 | 1.3872 (17) |
C5—H5A | 0.9500 | C18—H18A | 0.9500 |
C6—C7 | 1.4625 (16) | C19—H19A | 0.9500 |
C7—C8 | 1.3472 (16) | C20—H20A | 0.9800 |
C7—H7A | 0.9500 | C20—H20B | 0.9800 |
C8—C9 | 1.4819 (16) | C20—H20C | 0.9800 |
C8—C12 | 1.5076 (15) | ||
C4—O1—H1O1 | 112.0 (13) | C10—C11—H11A | 109.3 |
C16—O3—H1O3 | 108.1 (12) | N1—C11—H11B | 109.3 |
C12—N1—C20 | 110.15 (9) | C10—C11—H11B | 109.3 |
C12—N1—C11 | 109.61 (9) | H11A—C11—H11B | 108.0 |
C20—N1—C11 | 109.52 (9) | N1—C12—C8 | 110.31 (9) |
C2—C1—C6 | 119.72 (11) | N1—C12—H12A | 109.6 |
C2—C1—H1A | 120.1 | C8—C12—H12A | 109.6 |
C6—C1—H1A | 120.1 | N1—C12—H12B | 109.6 |
C3—C2—C1 | 120.94 (11) | C8—C12—H12B | 109.6 |
C3—C2—H2A | 119.5 | H12A—C12—H12B | 108.1 |
C1—C2—H2A | 119.5 | C10—C13—C14 | 130.67 (11) |
C2—C3—C4 | 120.23 (11) | C10—C13—H13A | 114.7 |
C2—C3—H3A | 119.9 | C14—C13—H13A | 114.7 |
C4—C3—H3A | 119.9 | C15—C14—C19 | 118.59 (11) |
O1—C4—C5 | 123.05 (11) | C15—C14—C13 | 116.26 (10) |
O1—C4—C3 | 117.67 (11) | C19—C14—C13 | 125.13 (11) |
C5—C4—C3 | 119.27 (11) | C16—C15—C14 | 121.15 (11) |
C4—C5—C6 | 120.74 (11) | C16—C15—H15A | 119.4 |
C4—C5—H5A | 119.6 | C14—C15—H15A | 119.4 |
C6—C5—H5A | 119.6 | O3—C16—C15 | 121.89 (11) |
C1—C6—C5 | 119.07 (11) | O3—C16—C17 | 118.25 (11) |
C1—C6—C7 | 122.82 (11) | C15—C16—C17 | 119.85 (11) |
C5—C6—C7 | 117.90 (10) | C18—C17—C16 | 119.08 (11) |
C8—C7—C6 | 129.38 (11) | C18—C17—H17A | 120.5 |
C8—C7—H7A | 115.3 | C16—C17—H17A | 120.5 |
C6—C7—H7A | 115.3 | C17—C18—C19 | 121.80 (11) |
C7—C8—C9 | 117.96 (10) | C17—C18—H18A | 119.1 |
C7—C8—C12 | 124.30 (10) | C19—C18—H18A | 119.1 |
C9—C8—C12 | 117.72 (10) | C18—C19—C14 | 119.49 (11) |
O2—C9—C8 | 121.55 (11) | C18—C19—H19A | 120.3 |
O2—C9—C10 | 120.44 (11) | C14—C19—H19A | 120.3 |
C8—C9—C10 | 118.00 (10) | N1—C20—H20A | 109.5 |
C13—C10—C9 | 116.70 (10) | N1—C20—H20B | 109.5 |
C13—C10—C11 | 124.79 (10) | H20A—C20—H20B | 109.5 |
C9—C10—C11 | 118.51 (10) | N1—C20—H20C | 109.5 |
N1—C11—C10 | 111.60 (9) | H20A—C20—H20C | 109.5 |
N1—C11—H11A | 109.3 | H20B—C20—H20C | 109.5 |
C6—C1—C2—C3 | 0.52 (18) | C12—N1—C11—C10 | −60.87 (12) |
C1—C2—C3—C4 | 1.06 (18) | C20—N1—C11—C10 | 178.18 (10) |
C2—C3—C4—O1 | 179.88 (11) | C13—C10—C11—N1 | −152.54 (12) |
C2—C3—C4—C5 | −1.56 (18) | C9—C10—C11—N1 | 26.59 (15) |
O1—C4—C5—C6 | 178.98 (11) | C20—N1—C12—C8 | −174.22 (9) |
C3—C4—C5—C6 | 0.50 (17) | C11—N1—C12—C8 | 65.22 (12) |
C2—C1—C6—C5 | −1.56 (17) | C7—C8—C12—N1 | 142.85 (12) |
C2—C1—C6—C7 | 172.99 (11) | C9—C8—C12—N1 | −35.19 (14) |
C4—C5—C6—C1 | 1.06 (17) | C9—C10—C13—C14 | −179.80 (12) |
C4—C5—C6—C7 | −173.76 (10) | C11—C10—C13—C14 | −0.7 (2) |
C1—C6—C7—C8 | 31.69 (19) | C10—C13—C14—C15 | 160.79 (13) |
C5—C6—C7—C8 | −153.70 (12) | C10—C13—C14—C19 | −20.9 (2) |
C6—C7—C8—C9 | −174.71 (11) | C19—C14—C15—C16 | 2.09 (18) |
C6—C7—C8—C12 | 7.3 (2) | C13—C14—C15—C16 | −179.43 (11) |
C7—C8—C9—O2 | 4.94 (18) | C14—C15—C16—O3 | −179.37 (11) |
C12—C8—C9—O2 | −176.91 (11) | C14—C15—C16—C17 | −0.52 (18) |
C7—C8—C9—C10 | −176.05 (11) | O3—C16—C17—C18 | 177.59 (11) |
C12—C8—C9—C10 | 2.11 (16) | C15—C16—C17—C18 | −1.30 (18) |
O2—C9—C10—C13 | 0.53 (18) | C16—C17—C18—C19 | 1.55 (19) |
C8—C9—C10—C13 | −178.49 (11) | C17—C18—C19—C14 | 0.05 (18) |
O2—C9—C10—C11 | −178.66 (11) | C15—C14—C19—C18 | −1.85 (17) |
C8—C9—C10—C11 | 2.31 (17) | C13—C14—C19—C18 | 179.83 (11) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1O1···N1i | 0.96 (2) | 1.81 (2) | 2.7278 (14) | 160 (2) |
O3—H1O3···O2ii | 0.88 (2) | 1.87 (2) | 2.7359 (15) | 171 (2) |
C17—H17A···O3iii | 0.95 | 2.51 | 3.4032 (16) | 157 |
Symmetry codes: (i) −x+2, −y, −z; (ii) −x+1, −y, −z+1; (iii) −x+1, −y+1, −z+2. |
C20H17Cl2NO | F(000) = 744 |
Mr = 358.24 | Dx = 1.423 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
a = 7.540 (3) Å | Cell parameters from 3908 reflections |
b = 10.623 (4) Å | θ = 2.7–29.2° |
c = 21.119 (7) Å | µ = 0.39 mm−1 |
β = 98.671 (5)° | T = 100 K |
V = 1672.2 (10) Å3 | Needle, yellow |
Z = 4 | 0.32 × 0.08 × 0.08 mm |
Bruker APEX DUO CCD area-detector diffractometer | 2591 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.084 |
φ and ω scans | θmax = 25.5°, θmin = 2.0° |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | h = −9→9 |
k = −12→12 | |
3105 measured reflections | l = −5→25 |
3105 independent reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.077 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.192 | H-atom parameters constrained |
S = 1.18 | w = 1/[σ2(Fo2) + 13.4429P] where P = (Fo2 + 2Fc2)/3 |
3105 reflections | (Δ/σ)max < 0.001 |
218 parameters | Δρmax = 0.45 e Å−3 |
0 restraints | Δρmin = −0.43 e Å−3 |
Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K. |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refined as a 2-component twin. |
x | y | z | Uiso*/Ueq | ||
Cl1 | 0.8841 (2) | 0.46525 (14) | 0.06491 (7) | 0.0261 (4) | |
Cl2 | 0.6925 (2) | −0.18217 (14) | −0.22186 (7) | 0.0242 (4) | |
O1 | 0.6046 (5) | 0.0962 (4) | −0.04698 (18) | 0.0193 (9) | |
N1 | 0.9749 (6) | −0.1131 (4) | 0.0667 (2) | 0.0179 (10) | |
C1 | 0.7905 (8) | 0.1999 (6) | 0.1897 (3) | 0.0205 (13) | |
H1A | 0.7492 | 0.1153 | 0.1892 | 0.025* | |
C2 | 0.8325 (8) | 0.2615 (6) | 0.2487 (3) | 0.0244 (13) | |
H2A | 0.8193 | 0.2199 | 0.2876 | 0.029* | |
C3 | 0.8940 (8) | 0.3854 (6) | 0.2491 (3) | 0.0263 (14) | |
H3A | 0.9266 | 0.4275 | 0.2889 | 0.032* | |
C4 | 0.9085 (8) | 0.4479 (6) | 0.1928 (3) | 0.0264 (14) | |
H4A | 0.9477 | 0.5329 | 0.1934 | 0.032* | |
C5 | 0.8648 (8) | 0.3841 (5) | 0.1355 (3) | 0.0182 (12) | |
C6 | 0.8072 (7) | 0.2581 (5) | 0.1317 (3) | 0.0178 (12) | |
C7 | 0.7554 (7) | 0.1956 (5) | 0.0699 (3) | 0.0184 (12) | |
H7A | 0.6965 | 0.2461 | 0.0359 | 0.022* | |
C8 | 0.7825 (7) | 0.0744 (5) | 0.0562 (3) | 0.0156 (12) | |
C9 | 0.7007 (7) | 0.0275 (6) | −0.0089 (3) | 0.0181 (12) | |
C10 | 0.7323 (7) | −0.1071 (5) | −0.0242 (3) | 0.0158 (12) | |
C11 | 0.8378 (8) | −0.1877 (5) | 0.0269 (3) | 0.0186 (12) | |
H11A | 0.7555 | −0.2250 | 0.0542 | 0.022* | |
H11B | 0.8959 | −0.2573 | 0.0066 | 0.022* | |
C12 | 0.8874 (8) | −0.0179 (5) | 0.1009 (3) | 0.0179 (12) | |
H12A | 0.9794 | 0.0279 | 0.1305 | 0.021* | |
H12B | 0.8056 | −0.0598 | 0.1268 | 0.021* | |
C13 | 0.6595 (7) | −0.1495 (5) | −0.0815 (3) | 0.0165 (12) | |
H13A | 0.6044 | −0.0878 | −0.1106 | 0.020* | |
C14 | 0.6534 (7) | −0.2798 (5) | −0.1058 (3) | 0.0161 (12) | |
C15 | 0.6583 (7) | −0.3058 (5) | −0.1704 (3) | 0.0185 (12) | |
C16 | 0.6392 (8) | −0.4257 (6) | −0.1957 (3) | 0.0210 (13) | |
H16A | 0.6420 | −0.4397 | −0.2400 | 0.025* | |
C17 | 0.6158 (8) | −0.5253 (6) | −0.1554 (3) | 0.0229 (13) | |
H17A | 0.6032 | −0.6084 | −0.1721 | 0.027* | |
C18 | 0.6106 (8) | −0.5046 (6) | −0.0912 (3) | 0.0210 (13) | |
H18A | 0.5949 | −0.5729 | −0.0635 | 0.025* | |
C19 | 0.6288 (7) | −0.3818 (5) | −0.0674 (3) | 0.0187 (12) | |
H19A | 0.6242 | −0.3679 | −0.0232 | 0.022* | |
C20 | 1.0862 (8) | −0.1939 (6) | 0.1114 (3) | 0.0225 (13) | |
H20A | 1.1440 | −0.2573 | 0.0877 | 0.034* | |
H20B | 1.1783 | −0.1432 | 0.1375 | 0.034* | |
H20C | 1.0117 | −0.2359 | 0.1393 | 0.034* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.0287 (8) | 0.0196 (7) | 0.0305 (8) | −0.0023 (6) | 0.0065 (6) | 0.0026 (6) |
Cl2 | 0.0292 (8) | 0.0260 (8) | 0.0176 (7) | −0.0003 (6) | 0.0038 (6) | 0.0015 (6) |
O1 | 0.020 (2) | 0.018 (2) | 0.019 (2) | 0.0055 (17) | 0.0001 (17) | 0.0049 (17) |
N1 | 0.012 (2) | 0.019 (3) | 0.022 (2) | 0.002 (2) | 0.000 (2) | −0.002 (2) |
C1 | 0.019 (3) | 0.020 (3) | 0.023 (3) | 0.003 (2) | 0.005 (2) | −0.002 (2) |
C2 | 0.019 (3) | 0.027 (3) | 0.027 (3) | 0.006 (3) | 0.002 (3) | −0.002 (3) |
C3 | 0.023 (3) | 0.029 (4) | 0.027 (3) | 0.007 (3) | 0.002 (3) | −0.012 (3) |
C4 | 0.021 (3) | 0.023 (3) | 0.035 (4) | 0.001 (3) | 0.001 (3) | −0.005 (3) |
C5 | 0.016 (3) | 0.015 (3) | 0.023 (3) | 0.001 (2) | 0.003 (2) | 0.004 (2) |
C6 | 0.012 (3) | 0.018 (3) | 0.023 (3) | 0.003 (2) | 0.004 (2) | −0.003 (2) |
C7 | 0.014 (3) | 0.019 (3) | 0.023 (3) | 0.001 (2) | 0.005 (2) | 0.004 (2) |
C8 | 0.015 (3) | 0.015 (3) | 0.019 (3) | 0.000 (2) | 0.007 (2) | −0.002 (2) |
C9 | 0.013 (3) | 0.025 (3) | 0.018 (3) | −0.004 (2) | 0.007 (2) | 0.000 (2) |
C10 | 0.013 (3) | 0.018 (3) | 0.017 (3) | 0.003 (2) | 0.006 (2) | 0.004 (2) |
C11 | 0.020 (3) | 0.017 (3) | 0.019 (3) | 0.000 (2) | 0.003 (2) | −0.003 (2) |
C12 | 0.019 (3) | 0.017 (3) | 0.018 (3) | 0.000 (2) | 0.004 (2) | −0.005 (2) |
C13 | 0.016 (3) | 0.019 (3) | 0.014 (3) | 0.000 (2) | 0.002 (2) | 0.000 (2) |
C14 | 0.011 (3) | 0.020 (3) | 0.017 (3) | 0.002 (2) | 0.002 (2) | −0.001 (2) |
C15 | 0.015 (3) | 0.020 (3) | 0.020 (3) | 0.001 (2) | 0.002 (2) | −0.002 (2) |
C16 | 0.020 (3) | 0.026 (3) | 0.017 (3) | 0.000 (3) | 0.001 (2) | −0.005 (2) |
C17 | 0.023 (3) | 0.018 (3) | 0.027 (3) | −0.004 (3) | 0.001 (3) | −0.008 (3) |
C18 | 0.018 (3) | 0.024 (3) | 0.020 (3) | −0.003 (3) | −0.001 (2) | −0.001 (2) |
C19 | 0.016 (3) | 0.021 (3) | 0.019 (3) | 0.001 (2) | 0.001 (2) | −0.004 (2) |
C20 | 0.025 (3) | 0.020 (3) | 0.022 (3) | 0.002 (3) | 0.001 (3) | 0.001 (2) |
Cl1—C5 | 1.747 (6) | C10—C13 | 1.331 (8) |
Cl2—C15 | 1.749 (6) | C10—C11 | 1.508 (8) |
O1—C9 | 1.236 (7) | C11—H11A | 0.9900 |
N1—C20 | 1.447 (7) | C11—H11B | 0.9900 |
N1—C12 | 1.457 (7) | C12—H12A | 0.9900 |
N1—C11 | 1.462 (7) | C12—H12B | 0.9900 |
C1—C6 | 1.396 (8) | C13—C14 | 1.474 (8) |
C1—C2 | 1.402 (8) | C13—H13A | 0.9500 |
C1—H1A | 0.9500 | C14—C19 | 1.383 (8) |
C2—C3 | 1.395 (9) | C14—C15 | 1.398 (8) |
C2—H2A | 0.9500 | C15—C16 | 1.381 (8) |
C3—C4 | 1.381 (9) | C16—C17 | 1.386 (8) |
C3—H3A | 0.9500 | C16—H16A | 0.9500 |
C4—C5 | 1.382 (8) | C17—C18 | 1.381 (8) |
C4—H4A | 0.9500 | C17—H17A | 0.9500 |
C5—C6 | 1.406 (8) | C18—C19 | 1.397 (8) |
C6—C7 | 1.464 (8) | C18—H18A | 0.9500 |
C7—C8 | 1.343 (8) | C19—H19A | 0.9500 |
C7—H7A | 0.9500 | C20—H20A | 0.9800 |
C8—C12 | 1.501 (8) | C20—H20B | 0.9800 |
C8—C9 | 1.505 (8) | C20—H20C | 0.9800 |
C9—C10 | 1.492 (8) | ||
C20—N1—C12 | 110.4 (4) | N1—C11—H11B | 109.5 |
C20—N1—C11 | 110.1 (5) | C10—C11—H11B | 109.5 |
C12—N1—C11 | 109.1 (4) | H11A—C11—H11B | 108.1 |
C6—C1—C2 | 122.4 (6) | N1—C12—C8 | 112.1 (4) |
C6—C1—H1A | 118.8 | N1—C12—H12A | 109.2 |
C2—C1—H1A | 118.8 | C8—C12—H12A | 109.2 |
C3—C2—C1 | 118.5 (6) | N1—C12—H12B | 109.2 |
C3—C2—H2A | 120.8 | C8—C12—H12B | 109.2 |
C1—C2—H2A | 120.8 | H12A—C12—H12B | 107.9 |
C4—C3—C2 | 121.2 (6) | C10—C13—C14 | 128.4 (5) |
C4—C3—H3A | 119.4 | C10—C13—H13A | 115.8 |
C2—C3—H3A | 119.4 | C14—C13—H13A | 115.8 |
C3—C4—C5 | 118.6 (6) | C19—C14—C15 | 116.3 (5) |
C3—C4—H4A | 120.7 | C19—C14—C13 | 122.2 (5) |
C5—C4—H4A | 120.7 | C15—C14—C13 | 121.4 (5) |
C4—C5—C6 | 123.2 (6) | C16—C15—C14 | 122.9 (5) |
C4—C5—Cl1 | 117.7 (5) | C16—C15—Cl2 | 118.0 (4) |
C6—C5—Cl1 | 119.0 (5) | C14—C15—Cl2 | 119.1 (4) |
C1—C6—C5 | 116.1 (5) | C15—C16—C17 | 118.8 (5) |
C1—C6—C7 | 122.3 (5) | C15—C16—H16A | 120.6 |
C5—C6—C7 | 121.5 (5) | C17—C16—H16A | 120.6 |
C8—C7—C6 | 126.7 (5) | C18—C17—C16 | 120.4 (6) |
C8—C7—H7A | 116.6 | C18—C17—H17A | 119.8 |
C6—C7—H7A | 116.6 | C16—C17—H17A | 119.8 |
C7—C8—C12 | 125.1 (5) | C17—C18—C19 | 119.1 (6) |
C7—C8—C9 | 117.3 (5) | C17—C18—H18A | 120.4 |
C12—C8—C9 | 117.6 (5) | C19—C18—H18A | 120.4 |
O1—C9—C10 | 121.5 (5) | C14—C19—C18 | 122.4 (5) |
O1—C9—C8 | 121.2 (5) | C14—C19—H19A | 118.8 |
C10—C9—C8 | 117.2 (5) | C18—C19—H19A | 118.8 |
C13—C10—C9 | 117.6 (5) | N1—C20—H20A | 109.5 |
C13—C10—C11 | 124.0 (5) | N1—C20—H20B | 109.5 |
C9—C10—C11 | 118.3 (5) | H20A—C20—H20B | 109.5 |
N1—C11—C10 | 110.7 (5) | N1—C20—H20C | 109.5 |
N1—C11—H11A | 109.5 | H20A—C20—H20C | 109.5 |
C10—C11—H11A | 109.5 | H20B—C20—H20C | 109.5 |
C6—C1—C2—C3 | −0.4 (9) | C20—N1—C11—C10 | −174.5 (4) |
C1—C2—C3—C4 | 2.0 (9) | C12—N1—C11—C10 | 64.2 (6) |
C2—C3—C4—C5 | −1.6 (9) | C13—C10—C11—N1 | 149.3 (5) |
C3—C4—C5—C6 | −0.5 (9) | C9—C10—C11—N1 | −33.2 (7) |
C3—C4—C5—Cl1 | 180.0 (5) | C20—N1—C12—C8 | 175.3 (5) |
C2—C1—C6—C5 | −1.5 (8) | C11—N1—C12—C8 | −63.6 (6) |
C2—C1—C6—C7 | −177.1 (5) | C7—C8—C12—N1 | −149.2 (5) |
C4—C5—C6—C1 | 1.9 (8) | C9—C8—C12—N1 | 31.0 (7) |
Cl1—C5—C6—C1 | −178.5 (4) | C9—C10—C13—C14 | −172.8 (5) |
C4—C5—C6—C7 | 177.6 (5) | C11—C10—C13—C14 | 4.8 (9) |
Cl1—C5—C6—C7 | −2.9 (7) | C10—C13—C14—C19 | 37.6 (9) |
C1—C6—C7—C8 | −39.9 (9) | C10—C13—C14—C15 | −147.5 (6) |
C5—C6—C7—C8 | 144.7 (6) | C19—C14—C15—C16 | 0.3 (8) |
C6—C7—C8—C12 | −5.9 (9) | C13—C14—C15—C16 | −175.0 (5) |
C6—C7—C8—C9 | 173.9 (5) | C19—C14—C15—Cl2 | −179.0 (4) |
C7—C8—C9—O1 | −3.8 (8) | C13—C14—C15—Cl2 | 5.8 (7) |
C12—C8—C9—O1 | 176.1 (5) | C14—C15—C16—C17 | −0.6 (9) |
C7—C8—C9—C10 | 179.6 (5) | Cl2—C15—C16—C17 | 178.6 (4) |
C12—C8—C9—C10 | −0.6 (7) | C15—C16—C17—C18 | 0.4 (9) |
O1—C9—C10—C13 | 2.9 (8) | C16—C17—C18—C19 | 0.2 (9) |
C8—C9—C10—C13 | 179.6 (5) | C15—C14—C19—C18 | 0.3 (8) |
O1—C9—C10—C11 | −174.7 (5) | C13—C14—C19—C18 | 175.5 (5) |
C8—C9—C10—C11 | 1.9 (7) | C17—C18—C19—C14 | −0.5 (9) |
D—H···A | D—H | H···A | D···A | D—H···A |
C4—H4A···Cl2i | 0.95 | 2.85 | 3.587 (7) | 135 |
Symmetry code: (i) x+1/2, −y+1/2, z+1/2. |
Acknowledgements
The authors are grateful to the Ministry of Education and Culture of Indonesia for financial support (research grant No. 2013 for YE) and the Universiti Sains Malaysia for the X-ray measurements.
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