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

For the synthesis of bis­amides, see: Apurba *et al.* (2002[@bb1]); Fry *et al.* (2010[@bb5]). For similar bis­amide crystal structures, see: Booysen *et al.* (2009[@bb2]). For applications of bis­amides as catalysts, see: Maurya *et al.* (2003[@bb7]); Liu *et al.* (2011[@bb6]).

Experimental   {#sec2}
==============

 {#sec2.1}

### Crystal data   {#sec2.1.1}

C~16~H~16~N~2~O~4~*M* *~r~* = 300.31Triclinic,*a* = 4.6311 (3) Å*b* = 5.0435 (3) Å*c* = 15.2957 (9) Åα = 89.091 (4)°β = 83.315 (4)°γ = 85.956 (4)°*V* = 353.94 (4) Å^3^*Z* = 1Mo *K*α radiationμ = 0.10 mm^−1^*T* = 296 K0.34 × 0.24 × 0.11 mm

### Data collection   {#sec2.1.2}

Bruker APEXII CCD diffractometerAbsorption correction: gaussian (*SADABS*; Bruker, 2009[@bb4]) *T* ~min~ = 0.966, *T* ~max~ = 0.9899142 measured reflections1535 independent reflections924 reflections with *I* \> 2σ(*I*)*R* ~int~ = 0.033

### Refinement   {#sec2.1.3}

*R*\[*F* ^2^ \> 2σ(*F* ^2^)\] = 0.049*wR*(*F* ^2^) = 0.143*S* = 1.011535 reflections100 parametersH-atom parameters constrainedΔρ~max~ = 0.13 e Å^−3^Δρ~min~ = −0.16 e Å^−3^

 {#d5e471}

Data collection: *APEX2* (Bruker, 2009[@bb4]); cell refinement: *SAINT* (Bruker, 2009[@bb4]); data reduction: *SAINT*; program(s) used to solve structure: *SHELXS97* (Sheldrick, 2008[@bb8]); program(s) used to refine structure: *SHELXL97* (Sheldrick, 2008[@bb8]); molecular graphics: *DIAMOND* (Brandenburg, 2006[@bb3]); software used to prepare material for publication: *publCIF* (Westrip, 2010[@bb9]).

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

###### 

Click here for additional data file.

Crystal structure: contains datablock(s) I, global. DOI: [10.1107/S1600536812051963/lr2096sup1.cif](http://dx.doi.org/10.1107/S1600536812051963/lr2096sup1.cif)

###### 

Click here for additional data file.

Structure factors: contains datablock(s) I. DOI: [10.1107/S1600536812051963/lr2096Isup2.hkl](http://dx.doi.org/10.1107/S1600536812051963/lr2096Isup2.hkl)

###### 

Click here for additional data file.

Supplementary material file. DOI: [10.1107/S1600536812051963/lr2096Isup3.cml](http://dx.doi.org/10.1107/S1600536812051963/lr2096Isup3.cml)

Additional supplementary materials: [crystallographic information](http://scripts.iucr.org/cgi-bin/sendsupfiles?lr2096&file=lr2096sup0.html&mime=text/html); [3D view](http://scripts.iucr.org/cgi-bin/sendcif?lr2096sup1&Qmime=cif); [checkCIF report](http://scripts.iucr.org/cgi-bin/paper?lr2096&checkcif=yes)

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: [LR2096](http://scripts.iucr.org/cgi-bin/sendsup?lr2096)).

The authors gratefully acknowledge Professor Manfredo Hörner, Department of Chemistry, Universidade Federal de Santa Maria, Brazil, for his support and help with the X-ray measurements. They also thank PRONEX FAPERGS/CNPq 10/0009--2 and PRONEM FAPERGS/CNPq 11/2026--4 for funding this study.

Comment
=======

Nitrogenated compound amines, imines and amides are part of a broad class of molecules having a pharmacological and technological profile (Fry *et al.* 2010). Bisamides can be synthesized from a reaction between a diamine and an acylhalide under reflux (Apurba *et al.* 2002 ; Fry *et al.* 2010). Some synthesized bisamides have had their crystal structure determined (Booysen *et al.* 2009). However, others have been synthesized and applied to several reactions, such as the hydroformylation of phenol (Maurya *et al.* 2003) and due to the simplicity of the synthesis of these compounds, they have being applied to coupling reactions, such as the Suzuki reaction (Liu *et al.* 2011). The asymmetric unit is formed by one half of the molecule and the whole molecule is generated through a crystallographic center of symmetry placed in the mid-point of the C-C bond of the ethane bridging moiety (Fig. 1). Intramolecular and intermolecular classical hydrogen bond interactions are observed in the solid state. Each molecule participates in intermolecular hydrogen bond interactions with two other neighboring molecules through N^ii^--H0^ii^···O1 with a distance of 2.210 Å (symmetry code: (ii) -1 + *x*, 1 + *y*, *z*). The intramolecular hydrogen bonding systems forms six membered rings, showing a shorter distance of 1.763 Å (O2···H1--O1). These hydrogen bonding may contribute to the stabilization of the crystal structure (Fig. 2).

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

Ethylenediamine (0.1 mol, 6.6 ml) was added to a solution containing methyl salicylate (0.2 mol, 25.7 ml). The mixture was refluxed for 7 h. The reaction product was washed with ethyl acetate (3 times in 30 ml) and dried over CaCl~2~. After recrystallization from hexane, a yellow solid was obtained (23.1 g, 77%).

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

H atoms attached to aromatic C atoms were positioned with idealized geometry and were refined isotropic with *U*~eq~(H) set to 1.2 times of the *U*~eq~(C) using a riding model with C--H = 0.93 Å. H atoms attached to N atoms and to the ethylene fragment were located in difference Fourier maps. Their positional and isotropic displacement parameters were refined.

Figures
=======

![Molecular projection showing the asymmetric unit represented in dark colors. Ellipsoid probability: 50%. Symmetry codes: (i) 2--x, 1--y, 2--z](e-69-0o201-fig1){#Fap1}

![Packing diagram view showing the intramolecular e intermolecular hydrogen bond interactions. Some hydrogen atoms were omitted for clarity. (ii) -1 + x, 1 + y, z](e-69-0o201-fig2){#Fap2}

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

  ----------------------- ---------------------------------------
  C~16~H~16~N~2~O~4~      *Z* = 1
  *M~r~* = 300.31         *F*(000) = 158
  Triclinic, *P*1         *D*~x~ = 1.409 Mg m^−3^
  Hall symbol: -P 1       Mo *K*α radiation, λ = 0.71073 Å
  *a* = 4.6311 (3) Å      Cell parameters from 1575 reflections
  *b* = 5.0435 (3) Å      θ = 2.7--25.8°
  *c* = 15.2957 (9) Å     µ = 0.10 mm^−1^
  α = 89.091 (4)°         *T* = 296 K
  β = 83.315 (4)°         Block, colourless
  γ = 85.956 (4)°         0.34 × 0.24 × 0.11 mm
  *V* = 353.94 (4) Å^3^   
  ----------------------- ---------------------------------------

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

  ---------------------------------------------------------- -------------------------------------
  Bruker APEXII CCD diffractometer                           1535 independent reflections
  Radiation source: fine-focus sealed tube                   924 reflections with *I* \> 2σ(*I*)
  Graphite monochromator                                     *R*~int~ = 0.033
  φ and ω scans                                              θ~max~ = 27.1°, θ~min~ = 2.7°
  Absorption correction: gaussian (*SADABS*; Bruker, 2009)   *h* = −5→5
  *T*~min~ = 0.966, *T*~max~ = 0.989                         *k* = −6→6
  9142 measured reflections                                  *l* = −19→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*\[*F*^2^ \> 2σ(*F*^2^)\] = 0.049   Hydrogen site location: inferred from neighbouring sites
  *wR*(*F*^2^) = 0.143                  H-atom parameters constrained
  *S* = 1.01                            *w* = 1/\[σ^2^(*F*~o~^2^) + (0.0644*P*)^2^ + 0.0596*P*\] where *P* = (*F*~o~^2^ + 2*F*~c~^2^)/3
  1535 reflections                      (Δ/σ)~max~ \< 0.001
  100 parameters                        Δρ~max~ = 0.13 e Å^−3^
  0 restraints                          Δρ~min~ = −0.16 e Å^−3^
  ------------------------------------- -------------------------------------------------------------------------------------------------

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

  -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
  Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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~   
  O1    0.4041 (3)   1.1108 (3)   0.79344 (10)   0.0718 (5)           
  H1    0.4677       1.0900       0.8411         0.108\*              
  O2    0.7318 (3)   0.9317 (3)   0.90207 (9)    0.0629 (5)           
  N     1.0113 (3)   0.5534 (3)   0.87856 (10)   0.0507 (5)           
  H0    1.0709       0.4248       0.8433         0.061\*              
  C1    0.7459 (4)   0.7361 (3)   0.76153 (11)   0.0426 (5)           
  C2    0.5357 (4)   0.9263 (4)   0.73646 (12)   0.0496 (5)           
  C3    0.4584 (5)   0.9234 (5)   0.65190 (15)   0.0676 (6)           
  H3    0.3184       1.0495       0.6352         0.081\*              
  C4    0.5845 (5)   0.7384 (4)   0.59253 (14)   0.0649 (6)           
  H4    0.5312       0.7405       0.5357         0.078\*              
  C5    0.7895 (5)   0.5493 (5)   0.61620 (14)   0.0655 (6)           
  H5    0.8742       0.4220       0.5760         0.079\*              
  C6    0.8674 (5)   0.5507 (4)   0.69979 (13)   0.0589 (6)           
  H6    1.0068       0.4226       0.7156         0.071\*              
  C7    0.8293 (4)   0.7466 (4)   0.85175 (12)   0.0448 (5)           
  C8    1.1112 (4)   0.5513 (4)   0.96491 (12)   0.0523 (5)           
  H8A   1.1517       0.7304       0.9796         0.063\*              
  H8B   1.2913       0.4402       0.9636         0.063\*              
  ----- ------------ ------------ -------------- -------------------- --

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

  ---- ------------- ------------- ------------- -------------- -------------- --------------
       *U*^11^       *U*^22^       *U*^33^       *U*^12^        *U*^13^        *U*^23^
  O1   0.0882 (11)   0.0606 (9)    0.0622 (9)    0.0348 (8)     −0.0120 (8)    −0.0122 (7)
  O2   0.0780 (10)   0.0543 (9)    0.0545 (9)    0.0202 (7)     −0.0125 (7)    −0.0214 (7)
  N    0.0591 (10)   0.0484 (10)   0.0439 (9)    0.0123 (8)     −0.0115 (7)    −0.0116 (7)
  C1   0.0458 (10)   0.0388 (10)   0.0426 (10)   0.0022 (8)     −0.0050 (8)    −0.0043 (8)
  C2   0.0569 (11)   0.0402 (10)   0.0501 (11)   0.0053 (9)     −0.0049 (9)    −0.0011 (9)
  C3   0.0806 (15)   0.0620 (14)   0.0601 (13)   0.0147 (12)    −0.0198 (12)   0.0036 (11)
  C4   0.0828 (16)   0.0679 (15)   0.0459 (12)   −0.0029 (12)   −0.0165 (11)   −0.0007 (11)
  C5   0.0820 (15)   0.0642 (14)   0.0490 (12)   0.0113 (12)    −0.0094 (11)   −0.0158 (10)
  C6   0.0696 (13)   0.0567 (13)   0.0488 (12)   0.0176 (10)    −0.0111 (10)   −0.0120 (10)
  C7   0.0458 (10)   0.0420 (10)   0.0456 (10)   0.0040 (8)     −0.0041 (8)    −0.0085 (8)
  C8   0.0540 (11)   0.0563 (12)   0.0477 (11)   0.0058 (9)     −0.0154 (8)    −0.0091 (9)
  ---- ------------- ------------- ------------- -------------- -------------- --------------

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

  ------------------- ------------- --------------------- -------------
  O1---C2             1.349 (2)     C3---C4               1.365 (3)
  O1---H1             0.8206        C3---H3               0.9300
  O2---C7             1.245 (2)     C4---C5               1.372 (3)
  N---C7              1.334 (2)     C4---H4               0.9300
  N---C8              1.449 (2)     C5---C6               1.369 (3)
  N---H0              0.8600        C5---H5               0.9300
  C1---C6             1.383 (2)     C6---H6               0.9300
  C1---C2             1.400 (3)     C8---C8^i^            1.511 (4)
  C1---C7             1.478 (2)     C8---H8A              0.9700
  C2---C3             1.382 (3)     C8---H8B              0.9700
                                                          
  C2---O1---H1        109.5         C6---C5---C4          119.07 (19)
  C7---N---C8         122.58 (15)   C6---C5---H5          120.5
  C7---N---H0         118.6         C4---C5---H5          120.5
  C8---N---H0         118.8         C5---C6---C1          122.21 (18)
  C6---C1---C2        117.95 (17)   C5---C6---H6          118.9
  C6---C1---C7        123.62 (16)   C1---C6---H6          118.9
  C2---C1---C7        118.42 (15)   O2---C7---N           120.36 (17)
  O1---C2---C3        119.21 (17)   O2---C7---C1          120.87 (16)
  O1---C2---C1        121.37 (17)   N---C7---C1           118.78 (15)
  C3---C2---C1        119.42 (17)   N---C8---C8^i^        112.0 (2)
  C4---C3---C2        120.98 (19)   N---C8---H8A          109.2
  C4---C3---H3        119.5         C8^i^---C8---H8A      109.2
  C2---C3---H3        119.5         N---C8---H8B          109.2
  C3---C4---C5        120.4 (2)     C8^i^---C8---H8B      109.2
  C3---C4---H4        119.8         H8A---C8---H8B        107.9
  C5---C4---H4        119.8                               
                                                          
  C6---C1---C2---O1   178.94 (18)   C2---C1---C6---C5     0.3 (3)
  C7---C1---C2---O1   −2.0 (3)      C7---C1---C6---C5     −178.7 (2)
  C6---C1---C2---C3   −0.3 (3)      C8---N---C7---O2      −1.8 (3)
  C7---C1---C2---C3   178.77 (19)   C8---N---C7---C1      178.24 (17)
  O1---C2---C3---C4   −179.4 (2)    C6---C1---C7---O2     173.61 (19)
  C1---C2---C3---C4   −0.2 (4)      C2---C1---C7---O2     −5.4 (3)
  C2---C3---C4---C5   0.6 (4)       C6---C1---C7---N      −6.5 (3)
  C3---C4---C5---C6   −0.6 (4)      C2---C1---C7---N      174.55 (17)
  C4---C5---C6---C1   0.2 (4)       C7---N---C8---C8^i^   80.7 (3)
  ------------------- ------------- --------------------- -------------

Symmetry code: (i) −*x*+2, −*y*+1, −*z*+2.

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

  ----------------- --------- --------- ----------- ---------------
  *D*---H···*A*     *D*---H   H···*A*   *D*···*A*   *D*---H···*A*
  O1---H1···O2      0.82      1.76      2.495 (2)   148
  N---H0···O1^ii^   0.86      2.21      2.993 (2)   151
  ----------------- --------- --------- ----------- ---------------

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

###### Hydrogen-bond geometry (Å, °)

  *D*---H⋯*A*    *D*---H   H⋯*A*   *D*⋯*A*     *D*---H⋯*A*
  -------------- --------- ------- ----------- -------------
  O1---H1⋯O2     0.82      1.76    2.495 (2)   148
  N---H0⋯O1^i^   0.86      2.21    2.993 (2)   151

Symmetry code: (i) .
