[2-(1H-Indol-4-yl)ethyl]dipropylamine

In the title compound, C16H24N2, the aliphatic amine substituent is rotated almost orthogonally [C—C—C—C torsion angle = 75.7 (3)°] out of the plane of the indole unit. The amine N atom has a pyramidal configuration deviating by 0.380 (3) Å from the plane of the adjacent C atoms. All of the aliphatic groups are in extended transoid conformations. In the crystal, molecules form chains along the a axis via N—H⋯N hydrogen bonds.

In the title compound, C 16 H 24 N 2 , the aliphatic amine substituent is rotated almost orthogonally [C-C-C-C torsion angle = 75.7 (3) ] out of the plane of the indole unit. The amine N atom has a pyramidal configuration deviating by 0.380 (3) Å from the plane of the adjacent C atoms. All of the aliphatic groups are in extended transoid conformations. In the crystal, molecules form chains along the a axis via N-HÁ Á ÁN hydrogen bonds.

Related literature
For the synthesis and applications of the title compound, see: Srivastava et al. (1999).  Table 1 Hydrogen-bond geometry (Å , ).
When the mixture reached room temperature, it was filtered and the filtrate was poured in water and extracted with chloroform. The combined extract is washed with 10% brine solution, dried over Na 2 S0 4 and concentrated to afford the crude product, which was filtered through column. The obtained material was distilled to afford the pure product 3.62 g with a 79% yield. The product (0.3 g) was crystallized from methanol (15 ml) at room temperature to give colorless crystals that were used for data collection.

Refinement
Carbon-and nitrogen-bound H atoms were placed in calculated positions and were treated as riding on the parent C and N atoms with C-H = 0.96 (methyl), 0.97 (methylene) and N-H = 0.86 Å, U iso (H) = 1.2 or 1.5 U eq (C,N). The hydrogen atoms for methyl groups were placed in staggered positions. Rigid body restrains were applied to atoms N2, C11, C12 and C13 because of their excessive thermal motion    where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 0.22 e Å −3 Δρ min = −0.12 e Å −3

Special details
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.