Study On The Method Of Synthesizing Series Of Intermediates From N-ethyl-m-toluidine And Other Raw Materials And Preparing Dyes With BIT

The choice of diazo component and coupling component is the key to the synthesis of high-quality azo disperse dyes.Compared with traditional azo disperse dyes with benzene-azo-benzene derivative structure,using heterocyclic compounds as diazo components has higher molar extinction coefficient,color fastness and color gloss,and the introduction of ethyl,ester,methoxy and other substituents when using aniline derivatives as coupling components also significantly affects the dyeing performance.Therefore,the design and development of heterocyclic azo disperse dyes and aniline derivatives have become the focus of research on new dyes.In this thesis,a series of aniline derivatives used as dye intermediates were designed and prepared in accordance with the actual production and market demand of dye chemical enterprises.EMT-1,MAP,EMA and EPA were synthesized by hydroxypropylation and esterification reactions,and EMT-1,EMT-2,MAP-1,EMA-1,EPA-1,EPA-2 a series of intermediates;the influence of solvent type,raw material ratio,reaction temperature,type and amount of acid binding agent on the relative content of the products was investigated,and the complete transformation of the reaction raw materials was achieved,and the reaction conditions were relatively simple and easy to operate,which met the basic requirements for industrial production.Secondly,a disperse dye with heterocyclic compound-azo-aniline derivativs structure using BIT as the diazo component and EMT,EMT-1,EMT-2 and MAP-1 as the coupling components was developed;meanwhile,in response to the problems of excessive strong acid and subsequent treatment difficulties in the industrial production of heterocyclic disperse dyes using BIT as the diazo component,a new method was designed using alcohol ether solvent instead of strong acid as the diazonation medium.A new method was designed to replace the strong acid with alcohol ether solvent as the diazotization medium,and to add fluoroboric acid as the diazotization salt stabilizer,so that part of the organic solvent could be recycled as the next diazotization medium after the diazotization reaction.This thesis also established a preliminary qualitative and quantitative analysis of raw materials,intermediates and dyes by high performance liquid chromatography-mass spectrometry(HPLC-MS),from which the reaction process of intermediates was judged and the optimal process conditions for synthesizing intermediates were determined.The relative contents of the intermediates and dyes were quantified by area normalization method,and the synthesized intermediates and dyes were qualitatively analyzed by high performance liquid chromatography-triple quadrupole mass spectrometry(HPLC-MS),and the mass-to-charge ratio of the excimer ion peaks on the mass spectra were compared with the relative molecular masses of the target products to verify the synthesized target products.The four dyes synthesized were analyzed by UV spectrophotometer,which gave the maximum absorption wavelengths of the four dyes.