Journal of Applied Chemistry Vol. 7 , No. 25 , 2013 77 Journal of Applied Chemistry Synthesis and Characterization of Polysalicylaldehyde (PSA) by Oxidative Polycondensation of Schiff base Compound [(2,4-dichlorophenylimino)methyl]-phenol Aliakbar Dehno Khalaji 1,  , Milad Kazemnejadi 1 , Hossein Mighani 1 and Debasis Das 2  . Corresponding Author: E-mail: alidkhalaji@yahoo.com 1. Introduction The OP method is one of the best methods for preparation of polymer compounds including -OH group and active functional groups such as -NH2, - CHO and –COOH. The main advantage of this method is the use of easily found, cheap, and simple structured oxidants. Until now, many studies on polymerization and reaction mechanisms of polyphenols by oxidative polycondensation method have been reported [1-5]. In this paper, we report the synthesis of PSA from the OP of sal-2,4-Clan as new precursor (Scheme 1). NaOCL KOH OH O NH 2 Cl + N Cl OH O * * n CH 3 OH Cl Cl O Hydrolysis Scheme 1. Chemical structure and preparation of sal-2,4-Clan and PSA 2. Experimental 2.1. Materials and Instruments All solvents and reagents were have been purchased from Merck Co. and used as received. Infrared spectra are recorded using KBr disk on a FT-IR (Perkin– Elmer) spectrometer. 1 H-NMR spectra are measured on a BRUKER DRX-400 AVANCE spectrometer at 400 MHz. All chemical shifts are reported in δ units downfield from TMS. UV-Vis absorption spectra were recorded on a JASCO V-570 spectrophotometer; λmax in nm. Thermal studies have been performed on a Perkin Elmer TG/DTA lab system 1 (Technology by SII) in nitrogen atmosphere with a heating rate of 20 ºC/min in the temperature span of30–750 ºC. 2.2. Preparation of sal-2,4-Clan A solution of 2,4-Dichloroaniline (4.05g, 0.025mol) in 25 mL methanol is added drop-wise to a methanol solution of salycilaldehyde (3.05 g, 0.025 mole) under stirring condition. The reaction mixture is then refluxed for 2 h when the solution color turns yellow and allowed the solution to cool at room temperature over-night. The suitable crystals are filtered, washed 1 Department of Chemistry, Faculty of Science, Golestan University, Gorgan, Iran 2 Department of Chemistry, The University of Burdwan, Burdwan, West Bangal, India Article history: Received: 14 November 2012 Received in revised form: 5 January 2013 Accepted: 23 January 2013 Abstract In this paper, polysalisylaldehyde (PSA) has been synthesized from the oxidative polycondensation (OP) of 2-[(2,4-dichlorophenylimino)methyl]-phenol (sal-2,4-Clan) with NaOCl in an aqueous alkaline medium between 50 and 90°C and characterized by 1 H-NMR, FT-IR, UV-Vis and TGA/DTA techniques. The conversion of PSA was 61.23% in optimum conditions such as [sal-2,4-Clan]0 = 0.02, [KOH]0= 0.1 [NaOCl]0 = 0.12 mol/L at 90°C for 10 h. Additionally, the crystal structure of sal-2,4-Clan has been determined by single-crystal X-ray crystallography. Keywords: Polysalisylaldehyde; Oxidative polycondensation; X-ray crystallography.