N-Butyl-4-chlorobenzamide

In the title benzamide derivative, C11H14ClNO, the chlorobenzene and butylamine groups are each planar, with mean deviations from the planes of 0.013 and 0.030 Å, respectively, and a dihedral angle of 2.54 (9)° between the two planes. In the crystal structure, N—H⋯O hydrogen bonds link molecules in rows along a. Short intermolecular Cl⋯Cl interactions [3.4225 (5) Å] link these rows into sheets in the ac plane. Additional weak C—H⋯O and C—H⋯π interactions generate a three-dimensional network.

In the title benzamide derivative, C 11 H 14 ClNO, the chlorobenzene and butylamine groups are each planar, with mean deviations from the planes of 0.013 and 0.030 Å , respectively, and a dihedral angle of 2.54 (9) between the two planes. In the crystal structure, N-HÁ Á ÁO hydrogen bonds link molecules in rows along a. Short intermolecular ClÁ Á ÁCl interactions [3.4225 (5) Å ] link these rows into sheets in the ac plane. Additional weak C-HÁ Á ÁO and C-HÁ Á Á interactions generate a three-dimensional network.

Comment
The benzanilide core is present in compounds with such a wide range of biological activities that it has been called a privileged structure. N-substituted benzamides are well known anticancer compounds and the mechanism of action for N-substituted benzamide-induced apoptosis has been studied, using declopramide as a lead compound (Olsson et al., 2002). Nsubstituted benzamides inhibit the activity of nuclear factor-B and nuclear factor of activated T cells activity while inducing activator protein 1 activity in T lymphocytes (Lindgren et al., 2001). Various N-substituted benzamides exhibit potent antiemetic activity (Vega-noverola et al., 1989), while heterocyclic analogs of benzanilide derivatives are potassium channel activators (Calderone et al., 2006). o-Aryloxylation of N-substituted benzamides induced by the copper(II)/trimethylamine N-oxide system has been studied (Reinaud et al., 1991). N-Alkylated 2-nitrobenzamides are intermediates in the synthesis of dibenzo[b,e][1,4]diazepines (Zhichkin et al., 2007) and N-Acyl-2-nitrobenzamides are precursors of 2,3-disubstitued 3H-quinazoline-4-ones (Beccalli et al., 2005). A one-pot conversion of 2-nitro-n-arylbenzamides to 2,3-dihydro-1H-quinazoline-4-ones has also been reported (Yoo et al., 2005). The anomalous dual fluorescence of benzanilides has been assigned to the two lowest benzanilide singlet states (Lewis & Long, 1998) As part of our work on the structure of benzanildes and related compounds, we report here the structure of the title benzamide derivative, I, Fig. 1. The C1···C7/Cl system is planar with a maximum deviation of 0.0161 (7) Å from the least squares plane. The carbonyl oxygen atom O1 is displaced by 0.6102 (10) Å from this plane. The butylamine N1/C8···C11 fragment is also planar, maximum deviation 0.0365 (7) Å for C9. The dihedral angle between these two planes is 2.54 (9)°.
Bond distances within the molecule are normal (Allen et al., 1987) and similar to those found in the structures of related 4-chlorobenzamide derivatives (Saeed et al., 2008, Hempel et al., 2005. In the crystal structure N1-HN1···O1 hydrogen bonds, Table 1, link molecules into rows along a. Cl1···Cl1 interactions at 3.4225 (5) Å bridge these rows to form sheets in the ac plane, Fig. 2. The sheets are interconnected by weak C3-H3···O1 hydrogen bonds and C8-H8···π interactions involving the C2···C7 benzene ring to generate a three dimensional network, The H atom bound to N1 was located in a difference electron density map and refined freely with an isotropic displacement parameter. All other H-atoms were refined using a riding model with d(C-H) = 0.95 Å, U iso = 1.2U eq (C) for aromatic, 0.99Å, U iso = 1.2U eq (C) for CH 2 , and 0.98 Å, U iso = 1.5U eq (C) for CH 3 H atoms. Fig. 1. The structure of I showing the atom numbering with displacement ellipsoids drawn at the 50% probability level.

Special details
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 > 2sigma(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 )