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

For the crystal structure of 1-naphthyl quinoxalinyl ether, see: Hassan *et al.* (2009[@bb3]).

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

 {#sec2.1}

### Crystal data {#sec2.1.1}

C~18~H~12~N~2~O*M* *~r~* = 272.30Monoclinic,*a* = 6.808 (1) Å*b* = 7.609 (1) Å*c* = 26.234 (3) Åβ = 92.522 (2)°*V* = 1357.5 (3) Å^3^*Z* = 4Mo *K*α radiationμ = 0.08 mm^−1^*T* = 295 K0.45 × 0.15 × 0.10 mm

### Data collection {#sec2.1.2}

Bruker SMART APEX diffractometerAbsorption correction: none7510 measured reflections3094 independent reflections1950 reflections with *I* \> 2σ(*I*)*R* ~int~ = 0.032

### Refinement {#sec2.1.3}

*R*\[*F* ^2^ \> 2σ(*F* ^2^)\] = 0.048*wR*(*F* ^2^) = 0.127*S* = 1.043094 reflections190 parametersH-atom parameters constrainedΔρ~max~ = 0.17 e Å^−3^Δρ~min~ = −0.16 e Å^−3^

 {#d5e309}

Data collection: *APEX2* (Bruker, 2007[@bb2]); cell refinement: *SAINT* (Bruker, 2007[@bb2]); data reduction: *SAINT*; program(s) used to solve structure: *SHELXS97* (Sheldrick, 2008[@bb4]); program(s) used to refine structure: *SHELXL97* (Sheldrick, 2008[@bb4]); molecular graphics: *X-SEED* (Barbour, 2001[@bb1]); software used to prepare material for publication: *publCIF* (Westrip, 2009[@bb5]).

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

Crystal structure: contains datablocks global, I. DOI: [10.1107/S1600536809007855/tk2387sup1.cif](http://dx.doi.org/10.1107/S1600536809007855/tk2387sup1.cif)

Structure factors: contains datablocks I. DOI: [10.1107/S1600536809007855/tk2387Isup2.hkl](http://dx.doi.org/10.1107/S1600536809007855/tk2387Isup2.hkl)

Additional supplementary materials: [crystallographic information](http://scripts.iucr.org/cgi-bin/sendsupfiles?tk2387&file=tk2387sup0.html&mime=text/html); [3D view](http://scripts.iucr.org/cgi-bin/sendcif?tk2387sup1&Qmime=cif); [checkCIF report](http://scripts.iucr.org/cgi-bin/paper?tk2387&checkcif=yes)

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: [TK2387](http://scripts.iucr.org/cgi-bin/sendsup?tk2387)).

We thank the University of Malaya for supporting this study (FS358/2008 A).

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

2-Naphthol (2.88 g, 20 mmol) was mixed with sodium hydroxide (0.08 g, 20 mmol) in several drops of water. The water was then evaporated. The paste was heated with 2-chloroquinoxaline (3.29 g, 20 mmol) at 423--433 K for 6 h. The product was dissolved in water and the solution extracted with chloroform. The chloroform phase was dried over sodium sulfate; the evaporation of the solvent gave a product that was recrystallized from an ethyl acetate/hexane.

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

Carbon-bound H-atoms were placed in calculated positions (C---H 0.93 Å) and were included in the refinement in the riding model approximation, with *U*(H) set to 1.2*U*~eq~(C).

Figures
=======

![Thermal ellipsoid plot (Barbour, 2001) of the molecule of C18H12N2O at the 50% probability level. Hydrogen atoms are drawn as spheres of arbitrary radius.](e-65-0o732-fig1){#Fap1}

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

  ------------------------- ---------------------------------------
  C~18~H~12~N~2~O           *F*(000) = 568
  *M~r~* = 272.30           *D*~x~ = 1.332 Mg m^−3^
  Monoclinic, *P*2~1~/*c*   Mo *K*α radiation, λ = 0.71073 Å
  Hall symbol: -P 2ybc      Cell parameters from 1541 reflections
  *a* = 6.808 (1) Å         θ = 2.7--28.2°
  *b* = 7.609 (1) Å         µ = 0.08 mm^−1^
  *c* = 26.234 (3) Å        *T* = 295 K
  β = 92.522 (2)°           Block, colorless
  *V* = 1357.5 (3) Å^3^     0.45 × 0.15 × 0.10 mm
  *Z* = 4                   
  ------------------------- ---------------------------------------

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

  ------------------------------------------ --------------------------------------
  Bruker SMART APEX diffractometer           1950 reflections with *I* \> 2σ(*I*)
  Radiation source: fine-focus sealed tube   *R*~int~ = 0.032
  graphite                                   θ~max~ = 27.5°, θ~min~ = 2.8°
  ω scans                                    *h* = −6→8
  7510 measured reflections                  *k* = −9→8
  3094 independent reflections               *l* = −28→34
  ------------------------------------------ --------------------------------------

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*\[*F*^2^ \> 2σ(*F*^2^)\] = 0.048   Hydrogen site location: inferred from neighbouring sites
  *wR*(*F*^2^) = 0.127                  H-atom parameters constrained
  *S* = 1.04                            *w* = 1/\[σ^2^(*F*~o~^2^) + (0.0544*P*)^2^ + 0.1253*P*\] where *P* = (*F*~o~^2^ + 2*F*~c~^2^)/3
  3094 reflections                      (Δ/σ)~max~ = 0.001
  190 parameters                        Δρ~max~ = 0.17 e Å^−3^
  0 restraints                          Δρ~min~ = −0.16 e Å^−3^
  ------------------------------------- -------------------------------------------------------------------------------------------------

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

  ----- --------------- -------------- ------------- -------------------- --
        *x*             *y*            *z*           *U*~iso~\*/*U*~eq~   
  O1    0.11303 (15)    0.36756 (17)   0.59259 (4)   0.0477 (3)           
  N1    −0.13352 (19)   0.2389 (2)     0.47654 (5)   0.0459 (4)           
  N2    0.25074 (18)    0.24104 (18)   0.52218 (5)   0.0379 (3)           
  C1    0.2995 (2)      0.3759 (2)     0.61786 (6)   0.0392 (4)           
  C2    0.4441 (2)      0.4866 (2)     0.59948 (6)   0.0447 (4)           
  H2    0.4210          0.5499         0.5695        0.054\*              
  C3    0.6192 (2)      0.5003 (2)     0.62616 (6)   0.0435 (4)           
  H3    0.7168          0.5723         0.6138        0.052\*              
  C4    0.6559 (2)      0.4077 (2)     0.67216 (6)   0.0371 (4)           
  C5    0.5053 (2)      0.3003 (2)     0.69082 (6)   0.0394 (4)           
  C6    0.3253 (2)      0.2858 (2)     0.66207 (6)   0.0412 (4)           
  H6    0.2253          0.2147         0.6735        0.049\*              
  C7    0.8364 (2)      0.4201 (3)     0.70077 (6)   0.0483 (5)           
  H7    0.9372          0.4892         0.6888        0.058\*              
  C8    0.8642 (3)      0.3322 (3)     0.74553 (7)   0.0618 (6)           
  H8    0.9839          0.3414         0.7638        0.074\*              
  C9    0.7154 (3)      0.2285 (3)     0.76428 (7)   0.0694 (6)           
  H9    0.7355          0.1704         0.7953        0.083\*              
  C10   0.5402 (3)      0.2116 (3)     0.73751 (7)   0.0593 (5)           
  H10   0.4424          0.1406         0.7502        0.071\*              
  C11   0.0985 (2)      0.3003 (2)     0.54445 (6)   0.0375 (4)           
  C12   −0.0954 (2)     0.2999 (2)     0.52209 (6)   0.0439 (4)           
  H12   −0.1976         0.3445         0.5406        0.053\*              
  C13   0.0233 (2)      0.1738 (2)     0.45104 (6)   0.0389 (4)           
  C14   −0.0076 (3)     0.1015 (3)     0.40208 (6)   0.0520 (5)           
  H14   −0.1333         0.1008         0.3867        0.062\*              
  C15   0.1453 (3)      0.0325 (3)     0.37707 (7)   0.0561 (5)           
  H15   0.1237          −0.0157        0.3447        0.067\*              
  C16   0.3351 (3)      0.0340 (2)     0.39983 (7)   0.0524 (5)           
  H16   0.4385          −0.0139        0.3824        0.063\*              
  C17   0.3705 (2)      0.1044 (2)     0.44705 (6)   0.0430 (4)           
  H17   0.4977          0.1063         0.4615        0.052\*              
  C18   0.2149 (2)      0.1739 (2)     0.47388 (5)   0.0348 (4)           
  ----- --------------- -------------- ------------- -------------------- --

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

  ----- ------------- ------------- ------------- -------------- -------------- --------------
        *U*^11^       *U*^22^       *U*^33^       *U*^12^        *U*^13^        *U*^23^
  O1    0.0342 (6)    0.0636 (9)    0.0449 (6)    0.0032 (5)     −0.0035 (5)    −0.0096 (6)
  N1    0.0344 (8)    0.0508 (10)   0.0517 (8)    −0.0015 (6)    −0.0080 (6)    0.0037 (7)
  N2    0.0336 (7)    0.0387 (8)    0.0409 (7)    −0.0003 (6)    −0.0048 (5)    0.0016 (6)
  C1    0.0348 (9)    0.0424 (11)   0.0402 (9)    0.0010 (7)     −0.0013 (7)    −0.0076 (7)
  C2    0.0497 (10)   0.0453 (11)   0.0389 (9)    −0.0025 (8)    −0.0017 (7)    0.0046 (8)
  C3    0.0441 (9)    0.0424 (11)   0.0441 (9)    −0.0095 (8)    0.0033 (7)     0.0009 (8)
  C4    0.0376 (8)    0.0339 (10)   0.0398 (8)    0.0010 (7)     0.0004 (6)     −0.0055 (7)
  C5    0.0420 (9)    0.0356 (10)   0.0404 (9)    0.0010 (7)     0.0010 (7)     0.0008 (7)
  C6    0.0392 (9)    0.0390 (11)   0.0457 (9)    −0.0056 (7)    0.0052 (7)     −0.0005 (8)
  C7    0.0382 (9)    0.0534 (13)   0.0529 (10)   −0.0002 (8)    −0.0015 (7)    −0.0099 (9)
  C8    0.0510 (12)   0.0723 (16)   0.0603 (12)   0.0077 (10)    −0.0177 (9)    −0.0017 (10)
  C9    0.0681 (15)   0.0816 (17)   0.0571 (12)   0.0052 (12)    −0.0130 (10)   0.0210 (11)
  C10   0.0594 (12)   0.0617 (15)   0.0566 (11)   −0.0039 (10)   −0.0004 (9)    0.0194 (10)
  C11   0.0366 (9)    0.0351 (10)   0.0404 (8)    −0.0013 (7)    −0.0033 (7)    0.0026 (7)
  C12   0.0332 (8)    0.0476 (11)   0.0506 (10)   0.0030 (8)     −0.0019 (7)    0.0007 (8)
  C13   0.0387 (9)    0.0341 (10)   0.0431 (9)    −0.0050 (7)    −0.0058 (7)    0.0045 (7)
  C14   0.0502 (11)   0.0557 (13)   0.0486 (10)   −0.0079 (9)    −0.0138 (8)    −0.0009 (9)
  C15   0.0689 (13)   0.0558 (14)   0.0431 (10)   −0.0075 (10)   −0.0046 (9)    −0.0087 (9)
  C16   0.0559 (11)   0.0509 (13)   0.0507 (10)   0.0038 (9)     0.0047 (8)     −0.0040 (9)
  C17   0.0401 (9)    0.0415 (11)   0.0473 (9)    0.0018 (7)     −0.0013 (7)    0.0025 (8)
  C18   0.0360 (8)    0.0295 (9)    0.0386 (8)    −0.0029 (7)    −0.0036 (6)    0.0060 (7)
  ----- ------------- ------------- ------------- -------------- -------------- --------------

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

  -------------------- -------------- ----------------------- --------------
  O1---C11             1.3622 (18)    C7---H7                 0.9300
  O1---C1              1.4073 (18)    C8---C9                 1.391 (3)
  N1---C12             1.297 (2)      C8---H8                 0.9300
  N1---C13             1.377 (2)      C9---C10                1.363 (3)
  N2---C11             1.2928 (19)    C9---H9                 0.9300
  N2---C18             1.3778 (19)    C10---H10               0.9300
  C1---C6              1.352 (2)      C11---C12               1.421 (2)
  C1---C2              1.398 (2)      C12---H12               0.9300
  C2---C3              1.359 (2)      C13---C14               1.405 (2)
  C2---H2              0.9300         C13---C18               1.411 (2)
  C3---C4              1.410 (2)      C14---C15               1.360 (3)
  C3---H3              0.9300         C14---H14               0.9300
  C4---C5              1.415 (2)      C15---C16               1.399 (2)
  C4---C7              1.415 (2)      C15---H15               0.9300
  C5---C10             1.410 (2)      C16---C17               1.361 (2)
  C5---C6              1.414 (2)      C16---H16               0.9300
  C6---H6              0.9300         C17---C18               1.401 (2)
  C7---C8              1.357 (2)      C17---H17               0.9300
                                                              
  C11---O1---C1        118.73 (12)    C8---C9---H9            119.8
  C12---N1---C13       116.62 (13)    C9---C10---C5           120.83 (19)
  C11---N2---C18       115.58 (13)    C9---C10---H10          119.6
  C6---C1---C2         122.30 (15)    C5---C10---H10          119.6
  C6---C1---O1         117.50 (15)    N2---C11---O1           121.55 (13)
  C2---C1---O1         119.95 (14)    N2---C11---C12          124.14 (15)
  C3---C2---C1         118.92 (15)    O1---C11---C12          114.31 (14)
  C3---C2---H2         120.5          N1---C12---C11          121.72 (15)
  C1---C2---H2         120.5          N1---C12---H12          119.1
  C2---C3---C4         121.39 (16)    C11---C12---H12         119.1
  C2---C3---H3         119.3          N1---C13---C14          119.82 (15)
  C4---C3---H3         119.3          N1---C13---C18          121.02 (14)
  C3---C4---C5         118.72 (14)    C14---C13---C18         119.14 (15)
  C3---C4---C7         122.55 (16)    C15---C14---C13         120.36 (16)
  C5---C4---C7         118.72 (15)    C15---C14---H14         119.8
  C10---C5---C4        118.70 (15)    C13---C14---H14         119.8
  C10---C5---C6        122.33 (16)    C14---C15---C16         120.19 (16)
  C4---C5---C6         118.97 (14)    C14---C15---H15         119.9
  C1---C6---C5         119.65 (15)    C16---C15---H15         119.9
  C1---C6---H6         120.2          C17---C16---C15         120.98 (17)
  C5---C6---H6         120.2          C17---C16---H16         119.5
  C8---C7---C4         120.72 (17)    C15---C16---H16         119.5
  C8---C7---H7         119.6          C16---C17---C18         119.89 (16)
  C4---C7---H7         119.6          C16---C17---H17         120.1
  C7---C8---C9         120.65 (17)    C18---C17---H17         120.1
  C7---C8---H8         119.7          N2---C18---C17          119.67 (14)
  C9---C8---H8         119.7          N2---C18---C13          120.91 (14)
  C10---C9---C8        120.38 (18)    C17---C18---C13         119.43 (14)
  C10---C9---H9        119.8                                  
                                                              
  C11---O1---C1---C6   −119.60 (16)   C18---N2---C11---O1     178.93 (14)
  C11---O1---C1---C2   65.9 (2)       C18---N2---C11---C12    −0.3 (2)
  C6---C1---C2---C3    2.0 (3)        C1---O1---C11---N2      1.5 (2)
  O1---C1---C2---C3    176.20 (15)    C1---O1---C11---C12     −179.20 (15)
  C1---C2---C3---C4    −1.1 (3)       C13---N1---C12---C11    0.3 (2)
  C2---C3---C4---C5    −0.7 (2)       N2---C11---C12---N1     −0.2 (3)
  C2---C3---C4---C7    −179.77 (16)   O1---C11---C12---N1     −179.53 (15)
  C3---C4---C5---C10   −178.29 (16)   C12---N1---C13---C14    178.37 (16)
  C7---C4---C5---C10   0.8 (2)        C12---N1---C13---C18    0.1 (2)
  C3---C4---C5---C6    1.7 (2)        N1---C13---C14---C15    −178.25 (17)
  C7---C4---C5---C6    −179.25 (15)   C18---C13---C14---C15   0.0 (3)
  C2---C1---C6---C5    −1.1 (3)       C13---C14---C15---C16   −0.4 (3)
  O1---C1---C6---C5    −175.37 (14)   C14---C15---C16---C17   −0.2 (3)
  C10---C5---C6---C1   179.15 (16)    C15---C16---C17---C18   1.1 (3)
  C4---C5---C6---C1    −0.8 (2)       C11---N2---C18---C17    −179.07 (14)
  C3---C4---C7---C8    178.35 (17)    C11---N2---C18---C13    0.8 (2)
  C5---C4---C7---C8    −0.7 (3)       C16---C17---C18---N2    178.38 (15)
  C4---C7---C8---C9    −0.2 (3)       C16---C17---C18---C13   −1.5 (2)
  C7---C8---C9---C10   1.0 (3)        N1---C13---C18---N2     −0.7 (2)
  C8---C9---C10---C5   −0.9 (3)       C14---C13---C18---N2    −178.94 (15)
  C4---C5---C10---C9   0.0 (3)        N1---C13---C18---C17    179.13 (15)
  C6---C5---C10---C9   −179.97 (18)   C14---C13---C18---C17   0.9 (2)
  -------------------- -------------- ----------------------- --------------
