organic compounds
2,4-Bis(4-butoxyphenyl)-3-azabicyclo[3.3.1]nonan-9-one
aDepartment of Image Science and Engineering, Pukyong National University, Busan 608 737, Republic of Korea, and bDepartment of Chemistry, IIT Madras, Chennai, TamilNadu, India
*Correspondence e-mail: ytjeong@pknu.ac.kr
In the title compound, C28H37NO3, a crystallographic mirror plane bisects the molecule (one half-molecule in the asymmetric unit). The title compound exists in a twin-chair conformation with an equatorial orientation of the 4-butoxyphenyl groups. Both sides of the secondary amino group carry the 4-butoxyphenyl groups at an angle of 38.54 (3)° with respect to one another.
Related literature
For the synthesis and biological activity of 3-azabicyclo[3.3.1] nonan-9-ones, see: Jeyaraman & Avila (1981); Barker et al. (2005); Parthiban et al. (2009a, 2010b,c); Cox et al. (1985). For related structures, see: Parthiban et al. (2009b,c, 2010a); Smith-Verdier et al. (1983); Padegimas & Kovacic (1972). For ring puckering parameters, see: Cremer & Pople (1975); Nardelli (1983).
Experimental
Crystal data
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Data collection: APEX2 (Bruker, 2004); cell APEX2 and SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus and XPREP (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97.
Supporting information
10.1107/S1600536811005058/bq2279sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536811005058/bq2279Isup2.hkl
The title compound was synthesized by a modified and an optimized Mannich condensation in one-pot, using 4-butoxybenzaldehyde (0.1 mol, 17.82 g/17.29 ml), cyclohexanone (0.05 mol, 4.90 g/5.18 ml) and ammonium acetate (0.075 mol, 5.78 g) in a 50 ml of absolute ethanol. The mixture was gently warmed on a hot plate at 303–308 K (30–35° C) with moderate stirring till the complete consumption of the starting materials, which was monitored by TLC. At the end, the crude azabicyclic ketone was separated by filtration and gently washed with 1:5 cold ethanol-ether mixture. X-ray diffraction quality crystals of the title compound were obtained by slow evaporation from ethanol.
The nitrogen H atom was located in a difference Fourier map and refined isotropically. Other hydrogen atoms were fixed geometrically and allowed to ride on the parent carbon atoms with aromatic C—H = 0.93 Å, aliphatic C—H = 0.98Å and methylene C—H = 0.97 Å. The displacement parameters were set for phenyl, methylene and aliphatic H atoms at Uiso(H) = 1.2Ueq(C).
Data collection: APEX2 (Bruker, 2004); cell
APEX2 and SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus and XPREP (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).Fig. 1. Anisotropic displacement representation of the molecule with 30% probability ellipsoids. Symmetry code: (i) x, -y+1/2, z. |
C28H37NO3 | F(000) = 944 |
Mr = 435.59 | Dx = 1.188 Mg m−3 |
Orthorhombic, Pnma | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ac 2n | Cell parameters from 4431 reflections |
a = 7.7780 (5) Å | θ = 3.3–26.9° |
b = 31.457 (2) Å | µ = 0.08 mm−1 |
c = 9.9560 (6) Å | T = 298 K |
V = 2436.0 (3) Å3 | Block, colorless |
Z = 4 | 0.35 × 0.28 × 0.25 mm |
Bruker APEXII CCD area-detector diffractometer | 2991 independent reflections |
Radiation source: fine-focus sealed tube | 1900 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.025 |
phi and ω scans | θmax = 28.3°, θmin = 2.2° |
Absorption correction: multi-scan (SADABS; Bruker, 2004) | h = −10→9 |
Tmin = 0.974, Tmax = 0.981 | k = −21→41 |
10360 measured reflections | l = −11→13 |
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)] = 0.056 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.163 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.02 | w = 1/[σ2(Fo2) + (0.0606P)2 + 1.2024P] where P = (Fo2 + 2Fc2)/3 |
2991 reflections | (Δ/σ)max < 0.001 |
155 parameters | Δρmax = 0.32 e Å−3 |
0 restraints | Δρmin = −0.18 e Å−3 |
C28H37NO3 | V = 2436.0 (3) Å3 |
Mr = 435.59 | Z = 4 |
Orthorhombic, Pnma | Mo Kα radiation |
a = 7.7780 (5) Å | µ = 0.08 mm−1 |
b = 31.457 (2) Å | T = 298 K |
c = 9.9560 (6) Å | 0.35 × 0.28 × 0.25 mm |
Bruker APEXII CCD area-detector diffractometer | 2991 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2004) | 1900 reflections with I > 2σ(I) |
Tmin = 0.974, Tmax = 0.981 | Rint = 0.025 |
10360 measured reflections |
R[F2 > 2σ(F2)] = 0.056 | 0 restraints |
wR(F2) = 0.163 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.02 | Δρmax = 0.32 e Å−3 |
2991 reflections | Δρmin = −0.18 e Å−3 |
155 parameters |
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. 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 > σ(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 | ||
C1 | 1.1848 (3) | 0.71161 (6) | 0.10972 (19) | 0.0455 (5) | |
H1 | 1.2239 | 0.7136 | 0.2031 | 0.055* | |
C2 | 1.3471 (3) | 0.71050 (6) | 0.0188 (2) | 0.0487 (5) | |
H2 | 1.4165 | 0.6857 | 0.0432 | 0.058* | |
C3 | 1.4496 (4) | 0.7500 | 0.0466 (3) | 0.0494 (7) | |
C4 | 1.3130 (3) | 0.70937 (6) | −0.1338 (2) | 0.0523 (5) | |
H4A | 1.4208 | 0.7044 | −0.1801 | 0.063* | |
H4B | 1.2372 | 0.6857 | −0.1536 | 0.063* | |
C5 | 1.2325 (4) | 0.7500 | −0.1884 (3) | 0.0547 (7) | |
H5A | 1.1109 | 0.7500 | −0.1667 | 0.066* | |
H5B | 1.2429 | 0.7500 | −0.2855 | 0.066* | |
C6 | 1.0781 (3) | 0.67181 (6) | 0.09708 (18) | 0.0440 (4) | |
C7 | 0.9491 (3) | 0.66660 (6) | 0.0020 (2) | 0.0542 (5) | |
H7 | 0.9213 | 0.6891 | −0.0544 | 0.065* | |
C8 | 0.8618 (3) | 0.62882 (7) | −0.0105 (2) | 0.0560 (5) | |
H8 | 0.7765 | 0.6260 | −0.0753 | 0.067* | |
C9 | 0.9001 (3) | 0.59496 (6) | 0.0730 (2) | 0.0495 (5) | |
C10 | 1.0237 (3) | 0.59983 (6) | 0.1706 (2) | 0.0530 (5) | |
H10 | 1.0487 | 0.5775 | 0.2288 | 0.064* | |
C11 | 1.1108 (3) | 0.63806 (6) | 0.1821 (2) | 0.0500 (5) | |
H11 | 1.1936 | 0.6411 | 0.2489 | 0.060* | |
C12 | 0.8378 (3) | 0.52285 (6) | 0.1337 (2) | 0.0601 (6) | |
H12A | 0.8154 | 0.5296 | 0.2271 | 0.072* | |
H12B | 0.9567 | 0.5139 | 0.1253 | 0.072* | |
C13 | 0.7190 (3) | 0.48792 (7) | 0.0868 (3) | 0.0663 (6) | |
H13A | 0.6013 | 0.4978 | 0.0945 | 0.080* | |
H13B | 0.7413 | 0.4825 | −0.0075 | 0.080* | |
C14 | 0.7355 (4) | 0.44743 (7) | 0.1615 (3) | 0.0752 (7) | |
H14A | 0.7082 | 0.4523 | 0.2553 | 0.090* | |
H14B | 0.8538 | 0.4377 | 0.1566 | 0.090* | |
C15 | 0.6187 (4) | 0.41318 (8) | 0.1070 (3) | 0.0882 (9) | |
H15A | 0.5020 | 0.4231 | 0.1080 | 0.132* | |
H15B | 0.6283 | 0.3882 | 0.1618 | 0.132* | |
H15C | 0.6517 | 0.4065 | 0.0165 | 0.132* | |
N1 | 1.0856 (3) | 0.7500 | 0.0803 (2) | 0.0456 (5) | |
O1 | 1.5979 (3) | 0.7500 | 0.0826 (2) | 0.0692 (6) | |
O2 | 0.8061 (2) | 0.55880 (5) | 0.05158 (16) | 0.0662 (5) | |
H1N | 0.991 (4) | 0.7500 | 0.127 (3) | 0.052 (9)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0549 (11) | 0.0463 (10) | 0.0354 (10) | 0.0017 (9) | −0.0014 (8) | 0.0015 (8) |
C2 | 0.0523 (11) | 0.0457 (10) | 0.0480 (11) | 0.0066 (9) | −0.0010 (9) | 0.0022 (8) |
C3 | 0.0480 (16) | 0.0612 (17) | 0.0392 (15) | 0.000 | −0.0013 (13) | 0.000 |
C4 | 0.0609 (12) | 0.0500 (11) | 0.0459 (11) | −0.0011 (9) | 0.0079 (10) | −0.0064 (9) |
C5 | 0.0652 (19) | 0.0616 (18) | 0.0374 (15) | 0.000 | −0.0012 (14) | 0.000 |
C6 | 0.0516 (10) | 0.0444 (10) | 0.0360 (10) | 0.0038 (8) | 0.0046 (8) | 0.0018 (8) |
C7 | 0.0670 (13) | 0.0523 (12) | 0.0434 (11) | 0.0004 (10) | −0.0066 (10) | 0.0120 (9) |
C8 | 0.0617 (12) | 0.0598 (13) | 0.0465 (12) | −0.0056 (10) | −0.0106 (10) | 0.0068 (9) |
C9 | 0.0540 (11) | 0.0458 (10) | 0.0487 (12) | 0.0017 (9) | 0.0047 (9) | 0.0021 (9) |
C10 | 0.0566 (12) | 0.0458 (11) | 0.0565 (13) | 0.0079 (9) | −0.0016 (10) | 0.0125 (9) |
C11 | 0.0534 (11) | 0.0511 (11) | 0.0456 (11) | 0.0063 (9) | −0.0059 (9) | 0.0055 (9) |
C12 | 0.0604 (13) | 0.0494 (12) | 0.0704 (15) | 0.0043 (10) | 0.0027 (12) | 0.0078 (10) |
C13 | 0.0629 (13) | 0.0600 (14) | 0.0761 (17) | −0.0033 (11) | 0.0005 (12) | 0.0103 (12) |
C14 | 0.0776 (16) | 0.0589 (14) | 0.0893 (19) | 0.0063 (12) | 0.0013 (15) | 0.0050 (13) |
C15 | 0.104 (2) | 0.0565 (14) | 0.104 (2) | −0.0075 (14) | 0.0128 (18) | −0.0072 (14) |
N1 | 0.0490 (13) | 0.0441 (12) | 0.0439 (13) | 0.000 | 0.0054 (11) | 0.000 |
O1 | 0.0563 (13) | 0.0787 (15) | 0.0725 (16) | 0.000 | −0.0153 (12) | 0.000 |
O2 | 0.0762 (10) | 0.0504 (8) | 0.0721 (11) | −0.0099 (8) | −0.0117 (9) | 0.0099 (7) |
C1—N1 | 1.463 (2) | C9—O2 | 1.369 (2) |
C1—C6 | 1.507 (3) | C9—C10 | 1.376 (3) |
C1—C2 | 1.554 (3) | C10—C11 | 1.385 (3) |
C1—H1 | 0.9800 | C10—H10 | 0.9300 |
C2—C3 | 1.502 (2) | C11—H11 | 0.9300 |
C2—C4 | 1.543 (3) | C12—O2 | 1.417 (2) |
C2—H2 | 0.9800 | C12—C13 | 1.510 (3) |
C3—O1 | 1.208 (3) | C12—H12A | 0.9700 |
C3—C2i | 1.502 (2) | C12—H12B | 0.9700 |
C4—C5 | 1.523 (3) | C13—C14 | 1.481 (3) |
C4—H4A | 0.9700 | C13—H13A | 0.9700 |
C4—H4B | 0.9700 | C13—H13B | 0.9700 |
C5—C4i | 1.523 (3) | C14—C15 | 1.510 (4) |
C5—H5A | 0.9700 | C14—H14A | 0.9700 |
C5—H5B | 0.9700 | C14—H14B | 0.9700 |
C6—C11 | 1.382 (3) | C15—H15A | 0.9600 |
C6—C7 | 1.390 (3) | C15—H15B | 0.9600 |
C7—C8 | 1.374 (3) | C15—H15C | 0.9600 |
C7—H7 | 0.9300 | N1—C1i | 1.463 (2) |
C8—C9 | 1.384 (3) | N1—H1N | 0.87 (3) |
C8—H8 | 0.9300 | ||
N1—C1—C6 | 112.25 (17) | O2—C9—C8 | 115.55 (18) |
N1—C1—C2 | 109.31 (16) | C10—C9—C8 | 119.29 (19) |
C6—C1—C2 | 112.33 (15) | C9—C10—C11 | 119.77 (18) |
N1—C1—H1 | 107.6 | C9—C10—H10 | 120.1 |
C6—C1—H1 | 107.6 | C11—C10—H10 | 120.1 |
C2—C1—H1 | 107.6 | C6—C11—C10 | 121.80 (19) |
C3—C2—C4 | 106.96 (18) | C6—C11—H11 | 119.1 |
C3—C2—C1 | 107.76 (17) | C10—C11—H11 | 119.1 |
C4—C2—C1 | 115.76 (17) | O2—C12—C13 | 107.21 (19) |
C3—C2—H2 | 108.7 | O2—C12—H12A | 110.3 |
C4—C2—H2 | 108.7 | C13—C12—H12A | 110.3 |
C1—C2—H2 | 108.7 | O2—C12—H12B | 110.3 |
O1—C3—C2 | 124.15 (12) | C13—C12—H12B | 110.3 |
O1—C3—C2i | 124.15 (12) | H12A—C12—H12B | 108.5 |
C2—C3—C2i | 111.7 (2) | C14—C13—C12 | 114.7 (2) |
C5—C4—C2 | 113.74 (17) | C14—C13—H13A | 108.6 |
C5—C4—H4A | 108.8 | C12—C13—H13A | 108.6 |
C2—C4—H4A | 108.8 | C14—C13—H13B | 108.6 |
C5—C4—H4B | 108.8 | C12—C13—H13B | 108.6 |
C2—C4—H4B | 108.8 | H13A—C13—H13B | 107.6 |
H4A—C4—H4B | 107.7 | C13—C14—C15 | 112.4 (2) |
C4—C5—C4i | 114.1 (2) | C13—C14—H14A | 109.1 |
C4—C5—H5A | 108.7 | C15—C14—H14A | 109.1 |
C4i—C5—H5A | 108.7 | C13—C14—H14B | 109.1 |
C4—C5—H5B | 108.7 | C15—C14—H14B | 109.1 |
C4i—C5—H5B | 108.7 | H14A—C14—H14B | 107.9 |
H5A—C5—H5B | 107.6 | C14—C15—H15A | 109.5 |
C11—C6—C7 | 117.37 (18) | C14—C15—H15B | 109.5 |
C11—C6—C1 | 119.07 (18) | H15A—C15—H15B | 109.5 |
C7—C6—C1 | 123.54 (17) | C14—C15—H15C | 109.5 |
C8—C7—C6 | 121.36 (18) | H15A—C15—H15C | 109.5 |
C8—C7—H7 | 119.3 | H15B—C15—H15C | 109.5 |
C6—C7—H7 | 119.3 | C1—N1—C1i | 111.3 (2) |
C7—C8—C9 | 120.3 (2) | C1—N1—H1N | 109.8 (9) |
C7—C8—H8 | 119.8 | C1i—N1—H1N | 109.8 (9) |
C9—C8—H8 | 119.8 | C9—O2—C12 | 118.72 (17) |
O2—C9—C10 | 125.15 (18) | ||
N1—C1—C2—C3 | 58.7 (2) | C1—C6—C7—C8 | 176.3 (2) |
C6—C1—C2—C3 | −176.04 (17) | C6—C7—C8—C9 | 0.5 (3) |
N1—C1—C2—C4 | −61.0 (2) | C7—C8—C9—O2 | −179.7 (2) |
C6—C1—C2—C4 | 64.3 (2) | C7—C8—C9—C10 | 1.5 (3) |
C4—C2—C3—O1 | −111.7 (3) | O2—C9—C10—C11 | 179.82 (19) |
C1—C2—C3—O1 | 123.2 (3) | C8—C9—C10—C11 | −1.6 (3) |
C4—C2—C3—C2i | 66.0 (3) | C7—C6—C11—C10 | 2.4 (3) |
C1—C2—C3—C2i | −59.1 (3) | C1—C6—C11—C10 | −176.39 (18) |
C3—C2—C4—C5 | −52.9 (2) | C9—C10—C11—C6 | −0.4 (3) |
C1—C2—C4—C5 | 67.2 (2) | O2—C12—C13—C14 | 179.6 (2) |
C2—C4—C5—C4i | 43.6 (3) | C12—C13—C14—C15 | −177.8 (2) |
N1—C1—C6—C11 | −145.94 (19) | C6—C1—N1—C1i | 172.73 (12) |
C2—C1—C6—C11 | 90.4 (2) | C2—C1—N1—C1i | −61.9 (2) |
N1—C1—C6—C7 | 35.4 (3) | C10—C9—O2—C12 | −1.0 (3) |
C2—C1—C6—C7 | −88.3 (2) | C8—C9—O2—C12 | −179.72 (19) |
C11—C6—C7—C8 | −2.4 (3) | C13—C12—O2—C9 | −179.18 (19) |
Symmetry code: (i) x, −y+3/2, z. |
Experimental details
Crystal data | |
Chemical formula | C28H37NO3 |
Mr | 435.59 |
Crystal system, space group | Orthorhombic, Pnma |
Temperature (K) | 298 |
a, b, c (Å) | 7.7780 (5), 31.457 (2), 9.9560 (6) |
V (Å3) | 2436.0 (3) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.08 |
Crystal size (mm) | 0.35 × 0.28 × 0.25 |
Data collection | |
Diffractometer | Bruker APEXII CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2004) |
Tmin, Tmax | 0.974, 0.981 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 10360, 2991, 1900 |
Rint | 0.025 |
(sin θ/λ)max (Å−1) | 0.667 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.056, 0.163, 1.02 |
No. of reflections | 2991 |
No. of parameters | 155 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.32, −0.18 |
Computer programs: APEX2 (Bruker, 2004), APEX2 and SAINT-Plus (Bruker, 2004), SAINT-Plus and XPREP (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997).
Acknowledgements
This research was supported by the Industrial Technology Development program, which was conducted by the Ministry of Knowledge Economy of the Korean Government. The authors acknowledge the Department of Chemistry, IIT Madras, for the X-ray data collection.
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Naturally abundant diterpenoid/norditerpenoid alkaloids contain the 3-azabicyclononane nucleus, which is an important class of pharmacophore due to its broad spectrum of biological activities such as antibacterial, antimycobacterial, antifungal, anticancer, antitussive, anti-inflammatory, sedative, antipyretic and calcium antagonistic activity (Jeyaraman & Avila, 1981; Barker et al., 2005; Parthiban et al., 2009a, 2010b, 2010c). Its biological significant prompted the medicinal chemists to synthesize some structural analogs. Since the stereochemistry plays an important role in biological actions, it is important to establish the stereochemistry of the synthesized bio-potent molecules. For the synthesized title compound, several stereomers are possible with conformations such as chair-chair (Parthiban et al., 2009b, 2009c, 2010a; Cox et al., 1985), chair-boat (Smith-Verdier et al., 1983) and boat-boat (Padegimas & Kovacic, 1972). Hence, the title crystal was undertaken for this study to explore its stereochemistry, unambiguously.
The analysis of torsion angles, asymmetry parameters and puckering parameters calculated for the title compound shows that the piperidine ring adopts a near ideal chair conformation. According to Cremer & Pople, the total puckering amplitude, QT is -0.613 (2) Å and the phase angle θ is 178.67 (19)° (Cremer & Pople, 1975). The smallest displacement asymmetry parameters q2 and q3 are 0.005 (2) and -0.612 (2)°, respectively (Nardelli, 1983). However, the cyclohexane ring deviates from the ideal chair conformation according to Cremer and Pople by QT = 0.573 (2) and θ = 16.1 (2)° (Cremer & Pople, 1975) as well as Nardelli by q2 = 0.158 (2) and q3 = 0.550 (2)° (Nardelli, 1983). Hence, the title compound C28H37NO3, exists in a twin-chair conformation with equatorial orientation of the 4-butoxyphenyl groups on both sides of the secondary amino group on the heterocycle. The aryl groups are orientated at an angle of 38.54 (3)° to each other. The torsion angle of C3—C2—C1—C6 and its mirror image is 176.03 (4)°. The crystal packing is stabilized by weak van der Waals interactions.