Synthesis And Research Of Three Fine Chemicais

In this thesis, the research present situation on the development and synthesis ofpyrimidine heterocyclic compounds and plant growth regulator were reviewed, and5-nitro-guaiacol, hexanoic acid2-(diethylamino)ethyl ester as well as propylthiouracilwere chosed as researh topics.Part one: Synthesis of5-nitro-guaiacol. In this section, through consultingliterature, the advantages and disadvantages of various synthetic methods werecompared and cheap fuming nitric acid and o-acetylguaiacol have been chosen as rawmaterials; the mixture consisting of nitric acid and glacial acid (molar ratio:1:1.6) wasused as nitrating agent, and the total yield of sodium5-nitroguaiacolate was above to60%. Compared with the traditional method, the route presentd here is moreenvironment-friendly, simple and easy to achieve.Part two: Synthesis of hexanoic acid2-(diethylamino) ethyl ester. By comparisonamong different routes, such as chloride method, solid acid catalysis, acidifierscatalytic method, etc., we have selected to use the direct esterification of caproic acidand diethylamino ethanol. Through the optimization of the process, the total yield is96%. Compared with other methods, the route is simple, safe, and low cost.Part three: Synthesis of propylthiouracil. In this section, we selected ethylbutyrylacetate, thiourea, sodium ethoxide and the absolute ethanol as raw materials,synthesizes the propylthiouracil directly by one step. Through the optimization of theprocess, the total yield is85%. Compared with other methods, the route is simple andlow cost.