<span style="font-size:11.0pt;line-height:115%; font-family:"Calibri","sans-serif";mso-ascii-theme-font:minor-latin;mso-fareast-font-family: "Times New Roman";mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font: minor-latin;mso-bidi-font-family:Calibri;mso-bidi-theme-font:minor-latin; mso-ansi-language:EN-US;mso-fareast-language:EN-US;mso-bidi-language:AR-SA">Synthesis of 3-aryl- and hetaryl-azo- 2-carbethoxy-4,6-dimethylthieno- [2,3-<i>b</i>]pyridines and their application on polyester fibres as disperse dyes</span>

Abstract

<span style="font-size:11.0pt;line-height:115%; font-family:" calibri","sans-serif";mso-ascii-theme-font:minor-latin;mso-fareast-font-family:="" "times="" new="" roman";mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:="" minor-latin;mso-bidi-font-family:calibri;mso-bidi-theme-font:minor-latin;="" mso-ansi-language:en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">2-chloro-3-cyano-4,6-dimethylpyridine obtained from 3-cyano-4,6-dimethyl-2-pyridone by treatment with phosphorus pentachloride in refluxing phosphorus oxychloride was reacted with ethyl thioglyocollate in refluxing methanol containing anhydrous sodium carbonate to get 3-amino-2-carbethoxy- 4,6-dimethylthieno[2,3-<i>b</i>]pyridine. 3-Amino-2-carbethoxy thieno[2,3-<i>b</i>]pyridine derivative thus obtained was di.azotized and coupled with N,N-dialkylanilines and heterocyclic hydroxy couplers to result 3-aryl- and hetaryl-aw-2-carbethoxy-4,6-dimethylthieno[2,3-<i>b</i>]pyridines. These azo dyes when applied on polyester fibres as disperse dyes gave yellow to red violet shades with excellent pick up, moderate light fastness and good to very good sublimation fastness.</span>