Related literature {#sec1}
==================

For hydrogen-bond motifs, see: Bernstein *et al.* ( 1995[@bb1]).  For ring puckering parameters, see Cremer & Pople (1975[@bb4]). 

Experimental {#sec2}
============

 {#sec2.1}

### Crystal data {#sec2.1.1}

C~18~H~24~N~2~O~2~*M* *~r~* = 300.39Monoclinic,*a* = 6.2701 (5) Å*b* = 8.0990 (6) Å*c* = 15.8978 (13) Åβ = 98.275 (2)°*V* = 798.91 (11) Å^3^*Z* = 2Mo *K*α radiationμ = 0.08 mm^−1^*T* = 293 K0.19 × 0.17 × 0.15 mm

### Data collection {#sec2.1.2}

Bruker SMART APEX CCD diffractometerAbsorption correction: multi-scan (*SADABS*; Bruker, 1998[@bb2]) *T* ~min~ = 0.984, *T* ~max~ = 0.9874782 measured reflections1826 independent reflections1424 reflections with *I* \> 2σ(*I*)*R* ~int~ = 0.014

### Refinement {#sec2.1.3}

*R*\[*F* ^2^ \> 2σ(*F* ^2^)\] = 0.043*wR*(*F* ^2^) = 0.123*S* = 1.051826 reflections100 parametersH-atom parameters constrainedΔρ~max~ = 0.20 e Å^−3^Δρ~min~ = −0.14 e Å^−3^

 {#d5e419}

Data collection: *SMART* (Bruker, 2001[@bb3]); cell refinement: *SAINT* (Bruker, 2001[@bb3]); data reduction: *SAINT*; program(s) used to solve structure: *SHELXS97* (Sheldrick, 2008[@bb5]); program(s) used to refine structure: *SHELXL97* (Sheldrick, 2008[@bb5]); molecular graphics: *PLATON* (Spek, 2009[@bb6]); software used to prepare material for publication: *SHELXL97*. 

Supplementary Material
======================

Crystal structure: contains datablocks global, I. DOI: [10.1107/S1600536809052908/bt5127sup1.cif](http://dx.doi.org/10.1107/S1600536809052908/bt5127sup1.cif)

Structure factors: contains datablocks I. DOI: [10.1107/S1600536809052908/bt5127Isup2.hkl](http://dx.doi.org/10.1107/S1600536809052908/bt5127Isup2.hkl)

Additional supplementary materials: [crystallographic information](http://scripts.iucr.org/cgi-bin/sendsupfiles?bt5127&file=bt5127sup0.html&mime=text/html); [3D view](http://scripts.iucr.org/cgi-bin/sendcif?bt5127sup1&Qmime=cif); [checkCIF report](http://scripts.iucr.org/cgi-bin/paper?bt5127&checkcif=yes)

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: [BT5127](http://scripts.iucr.org/cgi-bin/sendsup?bt5127)). 

VV thanks the DST-India for funding through the Young Scientist-Fast Track Proposal. 

Comment
=======

The configuration and conformation of the title compound, (I) and the atom numbering scheme are shown in the *ORTEP* drawing (Fig.  1).  The piperidone ring exibits chair conformation as evident from the puckering parameters (Q)=0.549 (1) Å, θ = 173.4 (2) °, ψ = 181.9 (1) ° (Cremer & Pople, 1975). 

In the crystal structure, an intermolecular C---H···O bond is found generating R22(24) motif (Bernstein *et al.*,  1995). 

Experimental {#experimental}
============

A mixture of 4-piperidone monohydrate hydrochloride (2 mol), 1,4-bis(bromomethyl)benzene (1 mol) and potassium carbonate (6 mol) in anhydrous benzene was refluxed for 7 h. The completion of reaction was monitored by TLC.  Potassium carbonate was filtered off and the excess solvent was removed under reduced pressure.  The solid obtained was purified over a column of silica gel (60--120 mesh size) using benzene-ethyl acetate (60--80 °C) in the ratio of 20:80.  Yield: 40% m.p.  289°C. 

Refinement {#refinement}
==========

The H atoms were placed in calculated positions and allowed to ride on their carrier atoms with C---H = 0.93--0.97 Å.*U*~iso~ = 1.2*U*~eq~(C) for CH and CH~2~ groups. 

Figures
=======

![ The molecular structure of title compound with atom numbering scheme and 50% probability displacement ellipsoids.](e-66-0o170-fig1){#Fap1}

Crystal data {#tablewrapcrystaldatalong}
============

  ------------------------- ---------------------------------------
  C~18~H~24~N~2~O~2~        *F*(000) = 324
  *M~r~* = 300.39           *D*~x~ = 1.249 Mg m^−3^
  Monoclinic, *P*2~1~/*n*   Mo *K*α radiation, λ = 0.71073 Å
  Hall symbol: -P 2yn       Cell parameters from 2500 reflections
  *a* = 6.2701 (5) Å        θ = 2--30°
  *b* = 8.0990 (6) Å        µ = 0.08 mm^−1^
  *c* = 15.8978 (13) Å      *T* = 293 K
  β = 98.275 (2)°           Block, colourless
  *V* = 798.91 (11) Å^3^    0.19 × 0.17 × 0.15 mm
  *Z* = 2                   
  ------------------------- ---------------------------------------

Data collection {#tablewrapdatacollectionlong}
===============

  ------------------------------------------------------------ --------------------------------------
  Bruker SMART APEX CCD diffractometer                         1826 independent reflections
  Radiation source: fine-focus sealed tube                     1424 reflections with *I* \> 2σ(*I*)
  graphite                                                     *R*~int~ = 0.014
  ω scans                                                      θ~max~ = 27.5°, θ~min~ = 2.6°
  Absorption correction: multi-scan (*SADABS*; Bruker, 1998)   *h* = −8→4
  *T*~min~ = 0.984, *T*~max~ = 0.987                           *k* = −10→10
  4782 measured reflections                                    *l* = −20→19
  ------------------------------------------------------------ --------------------------------------

Refinement {#tablewraprefinementdatalong}
==========

  ------------------------------------- -------------------------------------------------------------------------------------------------
  Refinement on *F*^2^                  Primary atom site location: structure-invariant direct methods
  Least-squares matrix: full            Secondary atom site location: difference Fourier map
  *R*\[*F*^2^ \> 2σ(*F*^2^)\] = 0.043   Hydrogen site location: inferred from neighbouring sites
  *wR*(*F*^2^) = 0.123                  H-atom parameters constrained
  *S* = 1.05                            *w* = 1/\[σ^2^(*F*~o~^2^) + (0.0639*P*)^2^ + 0.1074*P*\] where *P* = (*F*~o~^2^ + 2*F*~c~^2^)/3
  1826 reflections                      (Δ/σ)~max~ \< 0.001
  100 parameters                        Δρ~max~ = 0.20 e Å^−3^
  0 restraints                          Δρ~min~ = −0.14 e Å^−3^
  ------------------------------------- -------------------------------------------------------------------------------------------------

Special details {#specialdetails}
===============

  -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
  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 *F*^2^ against ALL reflections.  The weighted *R*-factor *wR* and goodness of fit *S* are based on *F*^2^, conventional *R*-factors *R* are based on *F*, with *F* set to zero for negative *F*^2^. The threshold expression of *F*^2^ \> σ(*F*^2^) is used only for calculating *R*-factors(gt) *etc*.  and is not relevant to the choice of reflections for refinement. * R*-factors based on *F*^2^ are statistically about twice as large as those based on *F*, and *R*- factors based on ALL data will be even larger. 
  -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å^2^) {#tablewrapcoords}
==================================================================================================

  ----- -------------- -------------- -------------- -------------------- --
        *x*            *y*            *z*            *U*~iso~\*/*U*~eq~   
  C2    0.2931 (2)     0.43945 (15)   0.38729 (9)    0.0451 (3)           
  H2A   0.3278         0.4330         0.3299         0.054\*              
  H2B   0.4196         0.4060         0.4260         0.054\*              
  C3    0.2358 (2)     0.61783 (16)   0.40660 (10)   0.0544 (4)           
  H3A   0.2191         0.6276         0.4661         0.065\*              
  H3B   0.3519         0.6905         0.3959         0.065\*              
  C4    0.0312 (2)     0.66908 (16)   0.35253 (8)    0.0440 (3)           
  C5    −0.1488 (2)    0.54905 (18)   0.35354 (11)   0.0584 (4)           
  H5A   −0.2680        0.5796         0.3105         0.070\*              
  H5B   −0.1991        0.5528         0.4084         0.070\*              
  C6    −0.0757 (2)    0.37490 (18)   0.33662 (10)   0.0544 (4)           
  H6A   −0.1918        0.2982         0.3419         0.065\*              
  H6B   −0.0434        0.3682         0.2789         0.065\*              
  C7    0.1742 (2)     0.15730 (16)   0.37561 (9)    0.0493 (4)           
  H7A   0.2250         0.1575         0.3208         0.059\*              
  H7B   0.0458         0.0891         0.3705         0.059\*              
  C8    0.3452 (2)     0.07991 (14)   0.44028 (8)    0.0405 (3)           
  C9    0.3083 (2)     0.05404 (16)   0.52331 (8)    0.0450 (3)           
  H9    0.1799         0.0900         0.5400         0.054\*              
  C10   0.5395 (2)     0.02482 (16)   0.41824 (8)    0.0444 (3)           
  H10   0.5682         0.0411         0.3631         0.053\*              
  N1    0.11571 (16)   0.32682 (12)   0.39582 (7)    0.0395 (3)           
  O1    0.01374 (19)   0.79483 (13)   0.31091 (7)    0.0657 (4)           
  ----- -------------- -------------- -------------- -------------------- --

Atomic displacement parameters (Å^2^) {#tablewrapadps}
=====================================

  ----- ------------ ------------ ------------- ------------- ------------- -------------
        *U*^11^      *U*^22^      *U*^33^       *U*^12^       *U*^13^       *U*^23^
  C2    0.0372 (6)   0.0349 (7)   0.0605 (8)    −0.0033 (5)   −0.0021 (5)   0.0041 (6)
  C3    0.0595 (8)   0.0329 (7)   0.0659 (9)    −0.0062 (6)   −0.0079 (7)   0.0018 (6)
  C4    0.0549 (8)   0.0322 (6)   0.0448 (7)    0.0048 (5)    0.0072 (6)    0.0015 (5)
  C5    0.0415 (7)   0.0509 (9)   0.0821 (10)   0.0057 (6)    0.0064 (7)    0.0227 (7)
  C6    0.0423 (7)   0.0422 (8)   0.0731 (10)   −0.0085 (6)   −0.0107 (7)   0.0130 (7)
  C7    0.0586 (8)   0.0308 (7)   0.0540 (8)    −0.0024 (6)   −0.0075 (6)   −0.0006 (6)
  C8    0.0502 (7)   0.0233 (5)   0.0464 (7)    −0.0019 (5)   0.0015 (5)    −0.0002 (5)
  C9    0.0462 (7)   0.0374 (7)   0.0528 (8)    0.0024 (5)    0.0113 (6)    −0.0021 (5)
  C10   0.0573 (8)   0.0368 (7)   0.0401 (6)    −0.0039 (6)   0.0106 (6)    0.0016 (5)
  N1    0.0389 (5)   0.0288 (5)   0.0484 (6)    −0.0026 (4)   −0.0022 (4)   0.0059 (4)
  O1    0.0827 (8)   0.0385 (6)   0.0723 (7)    −0.0004 (5)   −0.0012 (6)   0.0175 (5)
  ----- ------------ ------------ ------------- ------------- ------------- -------------

Geometric parameters (Å, °) {#tablewrapgeomlong}
===========================

  ------------------------ -------------- ----------------------- --------------
  C2---N1                  1.4598 (16)    C6---H6A                0.9700
  C2---C3                  1.5304 (18)    C6---H6B                0.9700
  C2---H2A                 0.9700         C7---N1                 1.4685 (17)
  C2---H2B                 0.9700         C7---C8                 1.5104 (18)
  C3---C4                  1.4964 (19)    C7---H7A                0.9700
  C3---H3A                 0.9700         C7---H7B                0.9700
  C3---H3B                 0.9700         C8---C9                 1.3884 (18)
  C4---O1                  1.2109 (16)    C8---C10                1.3888 (19)
  C4---C5                  1.492 (2)      C9---C10^i^             1.3882 (18)
  C5---C6                  1.519 (2)      C9---H9                 0.9300
  C5---H5A                 0.9700         C10---C9^i^             1.3882 (18)
  C5---H5B                 0.9700         C10---H10               0.9300
  C6---N1                  1.4670 (16)                            
                                                                  
  N1---C2---C3             111.55 (11)    C5---C6---H6A           109.2
  N1---C2---H2A            109.3          N1---C6---H6B           109.2
  C3---C2---H2A            109.3          C5---C6---H6B           109.2
  N1---C2---H2B            109.3          H6A---C6---H6B          107.9
  C3---C2---H2B            109.3          N1---C7---C8            114.47 (10)
  H2A---C2---H2B           108.0          N1---C7---H7A           108.6
  C4---C3---C2             110.67 (11)    C8---C7---H7A           108.6
  C4---C3---H3A            109.5          N1---C7---H7B           108.6
  C2---C3---H3A            109.5          C8---C7---H7B           108.6
  C4---C3---H3B            109.5          H7A---C7---H7B          107.6
  C2---C3---H3B            109.5          C9---C8---C10           117.61 (11)
  H3A---C3---H3B           108.1          C9---C8---C7            120.72 (12)
  O1---C4---C5             123.01 (13)    C10---C8---C7           121.59 (12)
  O1---C4---C3             123.37 (13)    C10^i^---C9---C8        120.89 (12)
  C5---C4---C3             113.62 (11)    C10^i^---C9---H9        119.6
  C4---C5---C6             110.77 (12)    C8---C9---H9            119.6
  C4---C5---H5A            109.5          C9^i^---C10---C8        121.50 (12)
  C6---C5---H5A            109.5          C9^i^---C10---H10       119.3
  C4---C5---H5B            109.5          C8---C10---H10          119.3
  C6---C5---H5B            109.5          C2---N1---C6            109.77 (10)
  H5A---C5---H5B           108.1          C2---N1---C7            110.25 (11)
  N1---C6---C5             111.90 (12)    C6---N1---C7            108.36 (10)
  N1---C6---H6A            109.2                                  
                                                                  
  N1---C2---C3---C4        −54.57 (16)    C7---C8---C9---C10^i^   176.62 (11)
  C2---C3---C4---O1        −129.37 (15)   C9---C8---C10---C9^i^   0.3 (2)
  C2---C3---C4---C5        49.69 (17)     C7---C8---C10---C9^i^   −176.59 (12)
  O1---C4---C5---C6        129.33 (15)    C3---C2---N1---C6       59.82 (15)
  C3---C4---C5---C6        −49.73 (18)    C3---C2---N1---C7       179.12 (11)
  C4---C5---C6---N1        54.57 (17)     C5---C6---N1---C2       −60.02 (16)
  N1---C7---C8---C9        62.64 (17)     C5---C6---N1---C7       179.53 (12)
  N1---C7---C8---C10       −120.58 (14)   C8---C7---N1---C2       69.70 (15)
  C10---C8---C9---C10^i^   −0.3 (2)       C8---C7---N1---C6       −170.15 (12)
  ------------------------ -------------- ----------------------- --------------

Symmetry codes: (i) −*x*+1, −*y*, −*z*+1. 

Hydrogen-bond geometry (Å, °) {#tablewraphbondslong}
=============================

  ------------------- --------- --------- ------------- ---------------
  *D*---H···*A*       *D*---H   H···*A*   *D*···*A*     *D*---H···*A*
  C7---H7B···O1^ii^   0.97      2.56      3.2235 (17)   126
  ------------------- --------- --------- ------------- ---------------

Symmetry codes: (ii) *x*, *y*−1, *z*. 

###### Hydrogen-bond geometry (Å, °)

  *D*---H⋯*A*        *D*---H   H⋯*A*   *D*⋯*A*       *D*---H⋯*A*
  ------------------ --------- ------- ------------- -------------
  C7---H7*B*⋯O1^i^   0.97      2.56    3.2235 (17)   126

Symmetry code: (i) .