Synthesis And Study Of Thiazole Orange (TO)

In this thesis, various methods of synthetizing Thiazole Orange (TO) were compared. The study shows that the structure modification sites of TO are in the nitrogen atoms on the quinoline ring of the benzothiazole and the thiazole ring. Deriving to this two nitrogen atoms can obtain different thiazole orange. Based on this study, we modified TO and improved the efficiency for these methods:(1) Using2-mercaptobenzothiazole and p-tolyl methyl sulfonate as the raw materials, we brought methyl in the nitrogen atom of benzothiazole ring and synthetized3-methyl-2-methylthio benzothiazoliu p-toluenesulfonate. Using4-methyl-quinoline and1,3-dibromopropane as raw materials, we brought3-bromopropyl in the nitrogen atom of the quinoline ring and synthetized4-methyl-l-(3-bromopropyl) quinoline hydrobromic. Finally, we used iodine ion to substitute p-toluenesulfonic acid ion. But the displacement efficiency was not high resulting in low yield.So this method needed to improve.We synthetized3-methyl-2-methylthio benzothiazoliu hydroiodic directly avoiding the final ion exchange process and improving the yield.(2) In above-mentioned methods, thiol was produced in the final step. We used2-methyl-benzothiazole as the raw material, brought methyl in the thiazole ring and synthetized2,3-dimethyl-benzo thiazole iodized. We used4-chloroquinazoline as the raw material, brought3-bromopropyl in the ring and synthetize4-chloro-l-(3-bromopropyl) quinoline hydrobromic.