Synthesis, Crystal Structure and Thermal Stability of the Schiff Base N,N'-bis(2,4-dichlorobenzylidene-3-propylammonium) Amine Chloride

Abstract

New Schiff base compound N,N'-bis(2,4-dichlorobenzylidene-3-propylammonium)amine chloride obtained by a condensation reaction between 3,3’-iminidipropylamine (C<sub>6</sub>H<sub>17</sub>N<sub>3</sub>) and 2,4-dichlorobenzaldehyde (C<sub>7</sub>H<sub>4</sub>Cl<sub>2</sub>O) in 1:2 ratio in methanol. The compound is characterized by elemental analyze (CHN) and FT-IR (Fourier-transform infrared) spectroscopic technique which shows the presence of the imine group resulting from a condensation reaction and two potentiel donor sites. Crystal structure was obtained by single-crystal X-ray diffraction (RX). Compound crystallize in the orthorhombic system, space groupe Pnma with unit cell parameters: a = 7.0681(2) Å, b = 29,7679 (10) Å, c = 11.4545(4) Å, α =β =Ɣ = 90°, V = 2410.06 (14) Å<sup>3 </sup>and Z = 4. Due to a mirror plane through the molecule, the asymmetric unit consists of only half the molecule. In the crystal structure of the compound, the dihedral angle formed between an aromatic ring C08/C06/C07/C10/C13/C09 and the aliphatic group C11/C15/C14/N04/C14/C15/C11 is equal to 77.42°. In addition, the aromatic rings are in the Trans position with the aliphatic group compared to the imine bonds C12-N05 and the angle formed around C12 is 120.78 (11)° whose is sufficient to maintain the cycles in Trans configuration. Thermogravimetric analysis (TG) of the compound shows very good thermal stability and decomposition from 180°C.