| The fluorescent brightener derivated from stilbene is one of the most important fluorescent whitening agents, which is famous for its large kinds and producing capacity in fluorescent whitening agent industry. At present, stilbene derivatives account for over percent of eighty in total producing capacity of influorescent whitening agents, which are extensively used for whitening textile, paper, detergent and plastics.This topic has studied the synthesis of bis-benzoxazolyl-stilbene fluorescent brightener and its intermediates. The kind of fluorescent brightener belongs to flat ones, and has extremely high brightening strength and better application property used in synthetic fiber and plastics, especially in polyester fiber. Nowadays the resource of the products mainly depends on import in our country. So it possessed good benefit and economic value to explore a new path for synthesizing the products.This paper has reviewed the synthesis development of bis-benzoxazolyl-stilbene in recent years, and analysed their merits as well as shortcomings and feasibility. The result shows that all the synthesis methods comprise the condensation reaction of stilbene-4,4'-bis-formic acid with o-amino phenol or its deprivatives. However, The synthesis conditions of stilbene^,4'-bis-formic acid is severe. The product yield is lower, and the cost is higher. Besides that, large quantity of poisonous solvent is used in the condensation reaction, which must be recovered and reutilized. From the mentioned above, we have designed the full synthesis route for bis-benzoxazolyl-stilbene which starts from the basic organic materials, and highlighted studying its unite reactions. The optimal technology conditions have been determined. The synthesized intermediates and product have been identified by IR, 1HNMR and element analysis etc.. The results agree to document saying and actual samples. Meanwhile, new synthesis methods for some intermediates have been studied.
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