




Supporting information
![]() | Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536811019155/bh2353sup1.cif |
![]() | Structure factor file (CIF format) https://doi.org/10.1107/S1600536811019155/bh2353Isup2.hkl |
![]() | Chemical Markup Language (CML) file https://doi.org/10.1107/S1600536811019155/bh2353Isup3.cml |
Key indicators
- Single-crystal X-ray study
- T = 293 K
- Mean
(C-C) = 0.003 Å
- R factor = 0.045
- wR factor = 0.136
- Data-to-parameter ratio = 16.1
checkCIF/PLATON results
No syntax errors found
Alert level C PLAT480_ALERT_4_C Long H...A H-Bond Reported H18 .. O1 .. 2.91 Ang. PLAT480_ALERT_4_C Long H...A H-Bond Reported H14 .. O2 .. 2.82 Ang. PLAT480_ALERT_4_C Long H...A H-Bond Reported H10 .. O1 .. 2.67 Ang. PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L= 0.600 7
Alert level G PLAT128_ALERT_4_G Alternate Setting of Space-group P21/c ....... P21/n PLAT196_ALERT_1_G Missing _cell_measurement_theta_min datum .... ? PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature 293 K PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature 293 K PLAT793_ALERT_4_G The Model has Chirality at C2 (Verify) .... R PLAT793_ALERT_4_G The Model has Chirality at C5 (Verify) .... S PLAT793_ALERT_4_G The Model has Chirality at C6 (Verify) .... S
0 ALERT level A = Most likely a serious problem - resolve or explain 0 ALERT level B = A potentially serious problem, consider carefully 4 ALERT level C = Check. Ensure it is not caused by an omission or oversight 7 ALERT level G = General information/check it is not something unexpected 3 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 0 ALERT type 2 Indicator that the structure model may be wrong or deficient 0 ALERT type 3 Indicator that the structure quality may be low 8 ALERT type 4 Improvement, methodology, query or suggestion 0 ALERT type 5 Informative message, check
The compound, 3-methyl-2,6-diphenylpiperidin-4-one was obtained by adopting an earlier method (Sampath et al., 2003; Noller & Baliah, 1948) and it was reduced using amalgamated zinc in aqueous methanol solution in the presence of HCl, giving 3-methyl-2,6-diphenylpiperidine as a product. To a well stirred solution of 3,5-dimethyl-2,6-diphenylpiperidin-4-one (2 mM) and triethylamine (4 mM) in freshly distilled benzene (50 ml), a little excess amount of ethylchloroacetate (2.2 mM) in benzene (10 ml) was added drop-wise over about half an hour and stirring was continued until the completion of reaction. The reaction mixture was then poured into water and extracted with dichloromethane. Recrystallization of the title compound using pure ethanol resulted in suitable colorless crystals.
H atoms were positioned geometrically and refined using a riding model with C—H = 0.93 Å for aromatic H, 0.97 Å for methylene, 0.98 Å for methine, and 0.96 Å for methyl H atoms. The Uiso parameters for H atoms were constrained to be 1.5Ueq of the carrier atom for the methyl H atoms and 1.2Ueq of the carrier atom for the remaining H atoms.
Piperidines and its N-substituted derivatives show significant pharmacological properties (Parthiban et al., 2009; Aridoss et al., 2007). Substitution by electron withdrawing groups (CHO, COCH2CH3, COPh, NO, etc.) at N-th position of piperidine ring causes major changes in the ring conformation (Ravindran et al., 1991; Krishna Kumar & Krishna Pillay, 1996). In the title compound (Fig. 1), the ethylacetate group substituting the piperidine ring shows extended conformation and the hetero π electron delocalization through the atoms N1, C20, O1 and O2 causes twisted boat conformation for the piperidine core, with puckering amplitude, QT = 0.718 (1) Å and phase angle = 89.5 (2)° (Nardelli, 1995; Cremer & Pople, 1975).
The phenyl rings at C2 and C6 atoms are oriented in the axial and equatorial positions, respectively, and the dihedral angle between them is 49.8 (1)°. Similarly, the methyl group at C5 is also oriented in equatorial position. All these substitutions are confirmed by the respective torsion angles. In addition, the substitution of ethylacetate group on N1 atom showed extended conformation with respect to the piperidine ring, which is also confirmed by the torsion angles.
The packing diagram of the title compound viewed down a-axis is shown in Fig. 2. The molecules did not present any classical H-bonds. However, the molecules are involved in weak intra- and intermolecular C—H···O interactions (Table 1), which stabilize the molecules in the crystal packing. Interestingly, a C—H···π interaction (C3—H3B···Cg1; Cg1 is the centroid of the ring C13···C18) also helps for the crystal packing.
For the biological activity of related piperidines, see: Parthiban et al. (2009); Aridoss et al. (2007). For ring conformational analysis, see: Cremer & Pople (1975); Nardelli (1995). For the conformation of piperidine derivatives, see: Ravindran et al. (1991); Krishna Kumar & Krishna Pillay (1996). For the synthesis of the title compound, see: Sampath et al. (2003); Noller & Baliah (1948).
Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS (Enraf–Nonius, 1994); data reduction: XCAD4 (Harms, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).
C21H25NO2 | F(000) = 696 |
Mr = 323.42 | Dx = 1.201 Mg m−3 |
Monoclinic, P21/n | Cu Kα radiation, λ = 1.54178 Å |
Hall symbol: -P 2yn | Cell parameters from 25 reflections |
a = 10.4113 (3) Å | θ = 0–90° |
b = 10.6073 (6) Å | µ = 0.60 mm−1 |
c = 16.2782 (6) Å | T = 293 K |
β = 95.960 (2)° | Needle, colourless |
V = 1787.98 (13) Å3 | 0.26 × 0.22 × 0.18 mm |
Z = 4 |
Enraf–Nonius CAD-4 diffractometer | Rint = 0.012 |
Radiation source: fine-focus sealed tube | θmax = 72.0°, θmin = 4.8° |
Graphite monochromator | h = 0→12 |
ω scans | k = 0→13 |
3698 measured reflections | l = −20→19 |
3502 independent reflections | 3 standard reflections every 60 min |
2428 reflections with I > 2σ(I) | intensity decay: none |
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)] = 0.045 | H-atom parameters constrained |
wR(F2) = 0.136 | w = 1/[σ2(Fo2) + (0.0736P)2 + 0.2748P] where P = (Fo2 + 2Fc2)/3 |
S = 1.03 | (Δ/σ)max = 0.001 |
3502 reflections | Δρmax = 0.17 e Å−3 |
218 parameters | Δρmin = −0.20 e Å−3 |
0 restraints | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
0 constraints | Extinction coefficient: 0.0022 (4) |
Primary atom site location: structure-invariant direct methods |
C21H25NO2 | V = 1787.98 (13) Å3 |
Mr = 323.42 | Z = 4 |
Monoclinic, P21/n | Cu Kα radiation |
a = 10.4113 (3) Å | µ = 0.60 mm−1 |
b = 10.6073 (6) Å | T = 293 K |
c = 16.2782 (6) Å | 0.26 × 0.22 × 0.18 mm |
β = 95.960 (2)° |
Enraf–Nonius CAD-4 diffractometer | Rint = 0.012 |
3698 measured reflections | 3 standard reflections every 60 min |
3502 independent reflections | intensity decay: none |
2428 reflections with I > 2σ(I) |
R[F2 > 2σ(F2)] = 0.045 | 0 restraints |
wR(F2) = 0.136 | H-atom parameters constrained |
S = 1.03 | Δρmax = 0.17 e Å−3 |
3502 reflections | Δρmin = −0.20 e Å−3 |
218 parameters |
x | y | z | Uiso*/Ueq | ||
O1 | 0.92030 (13) | 0.42372 (12) | 0.12110 (7) | 0.0586 (4) | |
O2 | 0.99447 (12) | 0.61660 (11) | 0.15872 (7) | 0.0516 (3) | |
N1 | 0.90776 (13) | 0.49725 (13) | 0.25183 (8) | 0.0427 (3) | |
C2 | 0.81474 (15) | 0.39802 (16) | 0.26812 (10) | 0.0455 (4) | |
H2 | 0.7841 | 0.3620 | 0.2142 | 0.055* | |
C3 | 0.69751 (17) | 0.45929 (18) | 0.30030 (11) | 0.0516 (4) | |
H3A | 0.6370 | 0.3939 | 0.3123 | 0.062* | |
H3B | 0.6550 | 0.5127 | 0.2574 | 0.062* | |
C4 | 0.73118 (18) | 0.5382 (2) | 0.37787 (12) | 0.0584 (5) | |
H4A | 0.7073 | 0.4918 | 0.4254 | 0.070* | |
H4B | 0.6810 | 0.6153 | 0.3735 | 0.070* | |
C5 | 0.87457 (16) | 0.57150 (17) | 0.39184 (10) | 0.0470 (4) | |
H5 | 0.9212 | 0.4975 | 0.4155 | 0.056* | |
C6 | 0.92925 (15) | 0.60452 (16) | 0.30998 (9) | 0.0414 (4) | |
H6 | 0.8820 | 0.6777 | 0.2857 | 0.050* | |
C7 | 1.07053 (16) | 0.63999 (16) | 0.32679 (9) | 0.0435 (4) | |
C8 | 1.16351 (18) | 0.55226 (19) | 0.35314 (13) | 0.0587 (5) | |
H8 | 1.1416 | 0.4675 | 0.3555 | 0.070* | |
C9 | 1.2899 (2) | 0.5901 (2) | 0.37612 (15) | 0.0718 (6) | |
H9 | 1.3516 | 0.5301 | 0.3942 | 0.086* | |
C10 | 1.3249 (2) | 0.7134 (2) | 0.37269 (14) | 0.0680 (6) | |
H10 | 1.4095 | 0.7378 | 0.3888 | 0.082* | |
C11 | 1.2344 (2) | 0.8007 (2) | 0.34532 (14) | 0.0686 (6) | |
H11 | 1.2576 | 0.8851 | 0.3421 | 0.082* | |
C12 | 1.10831 (19) | 0.76434 (18) | 0.32231 (12) | 0.0563 (5) | |
H12 | 1.0477 | 0.8249 | 0.3034 | 0.068* | |
C13 | 0.87742 (17) | 0.28998 (16) | 0.31910 (10) | 0.0459 (4) | |
C14 | 0.81423 (19) | 0.22492 (19) | 0.37698 (11) | 0.0565 (5) | |
H14 | 0.7339 | 0.2528 | 0.3897 | 0.068* | |
C15 | 0.8691 (2) | 0.1193 (2) | 0.41592 (12) | 0.0676 (6) | |
H15 | 0.8256 | 0.0768 | 0.4546 | 0.081* | |
C16 | 0.9876 (2) | 0.0766 (2) | 0.39778 (13) | 0.0685 (6) | |
H16 | 1.0241 | 0.0051 | 0.4237 | 0.082* | |
C17 | 1.0513 (2) | 0.1403 (2) | 0.34120 (13) | 0.0657 (5) | |
H17 | 1.1318 | 0.1121 | 0.3291 | 0.079* | |
C18 | 0.99719 (19) | 0.24578 (18) | 0.30200 (12) | 0.0558 (5) | |
H18 | 1.0416 | 0.2879 | 0.2636 | 0.067* | |
C19 | 0.8953 (2) | 0.6789 (2) | 0.45370 (11) | 0.0642 (5) | |
H19A | 0.9856 | 0.6992 | 0.4622 | 0.096* | |
H19B | 0.8659 | 0.6536 | 0.5052 | 0.096* | |
H19C | 0.8476 | 0.7515 | 0.4328 | 0.096* | |
C20 | 0.93902 (16) | 0.50599 (16) | 0.17288 (10) | 0.0440 (4) | |
C21 | 1.0362 (2) | 0.6314 (2) | 0.07700 (12) | 0.0637 (5) | |
H21A | 0.9644 | 0.6169 | 0.0351 | 0.076* | |
H21B | 1.1039 | 0.5713 | 0.0688 | 0.076* | |
C22 | 1.0848 (3) | 0.7612 (2) | 0.07088 (15) | 0.0802 (7) | |
H22A | 1.1132 | 0.7740 | 0.0172 | 0.120* | |
H22B | 1.1558 | 0.7744 | 0.1125 | 0.120* | |
H22C | 1.0169 | 0.8199 | 0.0789 | 0.120* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0793 (9) | 0.0536 (8) | 0.0446 (7) | −0.0032 (7) | 0.0148 (6) | −0.0103 (6) |
O2 | 0.0663 (8) | 0.0519 (7) | 0.0388 (6) | −0.0084 (6) | 0.0165 (5) | 0.0009 (5) |
N1 | 0.0506 (8) | 0.0425 (7) | 0.0355 (7) | −0.0050 (6) | 0.0076 (6) | −0.0007 (6) |
C2 | 0.0476 (9) | 0.0477 (9) | 0.0408 (8) | −0.0065 (7) | 0.0024 (7) | 0.0012 (7) |
C3 | 0.0453 (9) | 0.0592 (11) | 0.0500 (10) | −0.0015 (8) | 0.0038 (7) | 0.0055 (8) |
C4 | 0.0522 (10) | 0.0690 (13) | 0.0566 (11) | −0.0021 (9) | 0.0179 (8) | −0.0046 (9) |
C5 | 0.0513 (9) | 0.0530 (10) | 0.0378 (8) | −0.0001 (8) | 0.0095 (7) | −0.0017 (7) |
C6 | 0.0464 (9) | 0.0409 (8) | 0.0376 (8) | 0.0002 (7) | 0.0068 (6) | −0.0019 (6) |
C7 | 0.0476 (9) | 0.0451 (9) | 0.0386 (8) | −0.0019 (7) | 0.0077 (7) | −0.0015 (7) |
C8 | 0.0526 (11) | 0.0519 (11) | 0.0712 (12) | −0.0010 (9) | 0.0048 (9) | 0.0060 (9) |
C9 | 0.0508 (11) | 0.0749 (15) | 0.0881 (16) | 0.0031 (10) | 0.0001 (10) | 0.0103 (12) |
C10 | 0.0519 (11) | 0.0813 (15) | 0.0705 (13) | −0.0152 (11) | 0.0052 (9) | −0.0012 (11) |
C11 | 0.0689 (13) | 0.0583 (12) | 0.0788 (14) | −0.0205 (11) | 0.0080 (11) | −0.0033 (11) |
C12 | 0.0594 (11) | 0.0460 (10) | 0.0630 (11) | −0.0039 (9) | 0.0044 (9) | −0.0018 (8) |
C13 | 0.0528 (9) | 0.0429 (9) | 0.0414 (8) | −0.0076 (7) | 0.0023 (7) | −0.0010 (7) |
C14 | 0.0594 (11) | 0.0592 (11) | 0.0507 (10) | −0.0094 (9) | 0.0047 (8) | 0.0073 (9) |
C15 | 0.0900 (16) | 0.0600 (12) | 0.0514 (11) | −0.0104 (11) | 0.0015 (10) | 0.0136 (9) |
C16 | 0.0953 (16) | 0.0522 (12) | 0.0539 (11) | 0.0051 (11) | −0.0124 (11) | 0.0025 (9) |
C17 | 0.0695 (13) | 0.0556 (12) | 0.0705 (13) | 0.0114 (10) | 0.0005 (10) | −0.0046 (10) |
C18 | 0.0613 (11) | 0.0481 (10) | 0.0591 (10) | 0.0012 (9) | 0.0116 (9) | −0.0002 (8) |
C19 | 0.0748 (13) | 0.0732 (14) | 0.0466 (10) | −0.0042 (11) | 0.0162 (9) | −0.0146 (9) |
C20 | 0.0492 (9) | 0.0448 (9) | 0.0389 (8) | 0.0021 (7) | 0.0094 (7) | 0.0016 (7) |
C21 | 0.0800 (13) | 0.0707 (13) | 0.0445 (10) | −0.0055 (11) | 0.0266 (9) | 0.0037 (9) |
C22 | 0.0898 (16) | 0.0844 (16) | 0.0706 (13) | −0.0249 (13) | 0.0288 (12) | 0.0115 (12) |
O1—C20 | 1.2148 (19) | C10—C11 | 1.362 (3) |
O2—C20 | 1.338 (2) | C10—H10 | 0.9300 |
O2—C21 | 1.4500 (19) | C11—C12 | 1.382 (3) |
N1—C20 | 1.3612 (19) | C11—H11 | 0.9300 |
N1—C2 | 1.473 (2) | C12—H12 | 0.9300 |
N1—C6 | 1.482 (2) | C13—C18 | 1.387 (2) |
C2—C13 | 1.522 (2) | C13—C14 | 1.388 (2) |
C2—C3 | 1.523 (2) | C14—C15 | 1.382 (3) |
C2—H2 | 0.9800 | C14—H14 | 0.9300 |
C3—C4 | 1.525 (3) | C15—C16 | 1.375 (3) |
C3—H3A | 0.9700 | C15—H15 | 0.9300 |
C3—H3B | 0.9700 | C16—C17 | 1.368 (3) |
C4—C5 | 1.528 (2) | C16—H16 | 0.9300 |
C4—H4A | 0.9700 | C17—C18 | 1.379 (3) |
C4—H4B | 0.9700 | C17—H17 | 0.9300 |
C5—C19 | 1.521 (2) | C18—H18 | 0.9300 |
C5—C6 | 1.543 (2) | C19—H19A | 0.9600 |
C5—H5 | 0.9800 | C19—H19B | 0.9600 |
C6—C7 | 1.515 (2) | C19—H19C | 0.9600 |
C6—H6 | 0.9800 | C21—C22 | 1.474 (3) |
C7—C8 | 1.379 (2) | C21—H21A | 0.9700 |
C7—C12 | 1.381 (2) | C21—H21B | 0.9700 |
C8—C9 | 1.389 (3) | C22—H22A | 0.9600 |
C8—H8 | 0.9300 | C22—H22B | 0.9600 |
C9—C10 | 1.361 (3) | C22—H22C | 0.9600 |
C9—H9 | 0.9300 | ||
C20—O2—C21 | 115.37 (14) | C10—C11—C12 | 120.3 (2) |
C20—N1—C2 | 116.41 (13) | C10—C11—H11 | 119.9 |
C20—N1—C6 | 121.04 (13) | C12—C11—H11 | 119.9 |
C2—N1—C6 | 119.48 (12) | C7—C12—C11 | 121.33 (19) |
N1—C2—C13 | 112.56 (13) | C7—C12—H12 | 119.3 |
N1—C2—C3 | 108.81 (14) | C11—C12—H12 | 119.3 |
C13—C2—C3 | 116.58 (14) | C18—C13—C14 | 117.88 (17) |
N1—C2—H2 | 106.0 | C18—C13—C2 | 119.25 (15) |
C13—C2—H2 | 106.0 | C14—C13—C2 | 122.56 (16) |
C3—C2—H2 | 106.0 | C15—C14—C13 | 120.83 (19) |
C2—C3—C4 | 113.29 (15) | C15—C14—H14 | 119.6 |
C2—C3—H3A | 108.9 | C13—C14—H14 | 119.6 |
C4—C3—H3A | 108.9 | C16—C15—C14 | 120.4 (2) |
C2—C3—H3B | 108.9 | C16—C15—H15 | 119.8 |
C4—C3—H3B | 108.9 | C14—C15—H15 | 119.8 |
H3A—C3—H3B | 107.7 | C17—C16—C15 | 119.4 (2) |
C3—C4—C5 | 112.78 (14) | C17—C16—H16 | 120.3 |
C3—C4—H4A | 109.0 | C15—C16—H16 | 120.3 |
C5—C4—H4A | 109.0 | C16—C17—C18 | 120.6 (2) |
C3—C4—H4B | 109.0 | C16—C17—H17 | 119.7 |
C5—C4—H4B | 109.0 | C18—C17—H17 | 119.7 |
H4A—C4—H4B | 107.8 | C17—C18—C13 | 120.92 (19) |
C19—C5—C4 | 109.96 (15) | C17—C18—H18 | 119.5 |
C19—C5—C6 | 111.23 (15) | C13—C18—H18 | 119.5 |
C4—C5—C6 | 111.50 (14) | C5—C19—H19A | 109.5 |
C19—C5—H5 | 108.0 | C5—C19—H19B | 109.5 |
C4—C5—H5 | 108.0 | H19A—C19—H19B | 109.5 |
C6—C5—H5 | 108.0 | C5—C19—H19C | 109.5 |
N1—C6—C7 | 112.66 (13) | H19A—C19—H19C | 109.5 |
N1—C6—C5 | 109.43 (13) | H19B—C19—H19C | 109.5 |
C7—C6—C5 | 109.80 (13) | O1—C20—O2 | 123.46 (15) |
N1—C6—H6 | 108.3 | O1—C20—N1 | 124.70 (16) |
C7—C6—H6 | 108.3 | O2—C20—N1 | 111.84 (14) |
C5—C6—H6 | 108.3 | O2—C21—C22 | 107.49 (17) |
C8—C7—C12 | 117.81 (17) | O2—C21—H21A | 110.2 |
C8—C7—C6 | 121.71 (16) | C22—C21—H21A | 110.2 |
C12—C7—C6 | 120.28 (16) | O2—C21—H21B | 110.2 |
C7—C8—C9 | 120.24 (19) | C22—C21—H21B | 110.2 |
C7—C8—H8 | 119.9 | H21A—C21—H21B | 108.5 |
C9—C8—H8 | 119.9 | C21—C22—H22A | 109.5 |
C10—C9—C8 | 121.1 (2) | C21—C22—H22B | 109.5 |
C10—C9—H9 | 119.4 | H22A—C22—H22B | 109.5 |
C8—C9—H9 | 119.4 | C21—C22—H22C | 109.5 |
C9—C10—C11 | 119.2 (2) | H22A—C22—H22C | 109.5 |
C9—C10—H10 | 120.4 | H22B—C22—H22C | 109.5 |
C11—C10—H10 | 120.4 | ||
C20—N1—C2—C13 | 108.65 (16) | C8—C9—C10—C11 | −0.8 (4) |
C6—N1—C2—C13 | −90.94 (17) | C9—C10—C11—C12 | 0.8 (3) |
C20—N1—C2—C3 | −120.56 (16) | C8—C7—C12—C11 | −1.5 (3) |
C6—N1—C2—C3 | 39.84 (19) | C6—C7—C12—C11 | 173.46 (16) |
N1—C2—C3—C4 | −57.33 (19) | C10—C11—C12—C7 | 0.4 (3) |
C13—C2—C3—C4 | 71.2 (2) | N1—C2—C13—C18 | −41.5 (2) |
C2—C3—C4—C5 | 17.3 (2) | C3—C2—C13—C18 | −168.23 (16) |
C3—C4—C5—C19 | 163.67 (16) | N1—C2—C13—C14 | 145.07 (16) |
C3—C4—C5—C6 | 39.8 (2) | C3—C2—C13—C14 | 18.3 (2) |
C20—N1—C6—C7 | −62.3 (2) | C18—C13—C14—C15 | −0.2 (3) |
C2—N1—C6—C7 | 138.25 (14) | C2—C13—C14—C15 | 173.29 (17) |
C20—N1—C6—C5 | 175.28 (14) | C13—C14—C15—C16 | −0.1 (3) |
C2—N1—C6—C5 | 15.8 (2) | C14—C15—C16—C17 | 0.5 (3) |
C19—C5—C6—N1 | 179.64 (15) | C15—C16—C17—C18 | −0.5 (3) |
C4—C5—C6—N1 | −57.23 (19) | C16—C17—C18—C13 | 0.2 (3) |
C19—C5—C6—C7 | 55.50 (19) | C14—C13—C18—C17 | 0.2 (3) |
C4—C5—C6—C7 | 178.64 (15) | C2—C13—C18—C17 | −173.55 (17) |
N1—C6—C7—C8 | −53.5 (2) | C21—O2—C20—O1 | −2.2 (3) |
C5—C6—C7—C8 | 68.8 (2) | C21—O2—C20—N1 | 177.33 (15) |
N1—C6—C7—C12 | 131.73 (16) | C2—N1—C20—O1 | −17.4 (2) |
C5—C6—C7—C12 | −106.04 (18) | C6—N1—C20—O1 | −177.46 (16) |
C12—C7—C8—C9 | 1.6 (3) | C2—N1—C20—O2 | 163.14 (14) |
C6—C7—C8—C9 | −173.36 (18) | C6—N1—C20—O2 | 3.1 (2) |
C7—C8—C9—C10 | −0.4 (3) | C20—O2—C21—C22 | 175.60 (17) |
Cg1 is the centroid of the C13–C18 phenyl ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
C2—H2···O1 | 0.98 | 2.28 | 2.749 (2) | 109 |
C18—H18···O1 | 0.93 | 2.91 | 3.519 (2) | 125 |
C14—H14···O2i | 0.93 | 2.82 | 3.406 (2) | 122 |
C10—H10···O1ii | 0.93 | 2.67 | 3.460 (3) | 144 |
C3—H3B···Cg1iii | 0.97 | 2.70 | 3.666 (2) | 172 |
Symmetry codes: (i) −x+3/2, y−1/2, −z+1/2; (ii) −x+5/2, y+1/2, −z+1/2; (iii) −x+3/2, y+1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C21H25NO2 |
Mr | 323.42 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 293 |
a, b, c (Å) | 10.4113 (3), 10.6073 (6), 16.2782 (6) |
β (°) | 95.960 (2) |
V (Å3) | 1787.98 (13) |
Z | 4 |
Radiation type | Cu Kα |
µ (mm−1) | 0.60 |
Crystal size (mm) | 0.26 × 0.22 × 0.18 |
Data collection | |
Diffractometer | Enraf–Nonius CAD-4 |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 3698, 3502, 2428 |
Rint | 0.012 |
(sin θ/λ)max (Å−1) | 0.617 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.045, 0.136, 1.03 |
No. of reflections | 3502 |
No. of parameters | 218 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.17, −0.20 |
Computer programs: CAD-4 EXPRESS (Enraf–Nonius, 1994), XCAD4 (Harms, 1996), SHELXS97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).
Cg1 is the centroid of the C13–C18 phenyl ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
C18—H18···O1 | 0.93 | 2.91 | 3.519 (2) | 125 |
C14—H14···O2i | 0.93 | 2.82 | 3.406 (2) | 122 |
C10—H10···O1ii | 0.93 | 2.67 | 3.460 (3) | 144 |
C3—H3B···Cg1iii | 0.97 | 2.70 | 3.666 (2) | 172 |
Symmetry codes: (i) −x+3/2, y−1/2, −z+1/2; (ii) −x+5/2, y+1/2, −z+1/2; (iii) −x+3/2, y+1/2, −z+1/2. |
Piperidines and its N-substituted derivatives show significant pharmacological properties (Parthiban et al., 2009; Aridoss et al., 2007). Substitution by electron withdrawing groups (CHO, COCH2CH3, COPh, NO, etc.) at N-th position of piperidine ring causes major changes in the ring conformation (Ravindran et al., 1991; Krishna Kumar & Krishna Pillay, 1996). In the title compound (Fig. 1), the ethylacetate group substituting the piperidine ring shows extended conformation and the hetero π electron delocalization through the atoms N1, C20, O1 and O2 causes twisted boat conformation for the piperidine core, with puckering amplitude, QT = 0.718 (1) Å and phase angle = 89.5 (2)° (Nardelli, 1995; Cremer & Pople, 1975).
The phenyl rings at C2 and C6 atoms are oriented in the axial and equatorial positions, respectively, and the dihedral angle between them is 49.8 (1)°. Similarly, the methyl group at C5 is also oriented in equatorial position. All these substitutions are confirmed by the respective torsion angles. In addition, the substitution of ethylacetate group on N1 atom showed extended conformation with respect to the piperidine ring, which is also confirmed by the torsion angles.
The packing diagram of the title compound viewed down a-axis is shown in Fig. 2. The molecules did not present any classical H-bonds. However, the molecules are involved in weak intra- and intermolecular C—H···O interactions (Table 1), which stabilize the molecules in the crystal packing. Interestingly, a C—H···π interaction (C3—H3B···Cg1; Cg1 is the centroid of the ring C13···C18) also helps for the crystal packing.