Study On The C-O, S-N Coupling Reaction Of Pyrimidinthiones With Alcohols And Morpholine Under Electrochemical Conditions

In 1893,Italian chemist Biginelli has discovered a multi-component reaction that can produce these multifunctional dihydropyrimidones（DHPM）in a simple one-pot process,which is an important organic synthesis intermediate.This structure has multiple reactive sites.In contrast,C2-DHPMs derivatives have more interesting pharmacological properties（such as calcium channel modulators,antihypertensive active agents）than other derivatives.These pharmacological properties cause people’s great interest.Although some synthetic methods have been established for C2-DHPMs derivatives,methods for synthesizing C2-DHPM derivatives under electrochemical conditions have been rarely reported.Therefore,we have developed a metal-free catalyst and oxidant-free C-O and S-N coupling reaction of3,4-dihydropyrimidine-2（1H）-thiones with alcohol and morpholine under electrochemical conditions,a variety of C2-functional pyrimidine derivatives have been synthesized.The main content of this thesis consists of the following three parts:1.A brief review of the research progress in the formation of C-O/C-N/C-S coupling reactions under electrochemical conditions.2.The synthesis method of desulfurization coupling reaction between3,4-dihydropyrimidinethione and alcohols under electrochemical conditions to construct C-O bond was explored.This reaction uses a cheap and easily available alcohol as the reaction solvent and substrate under a constant current.Under mild reaction conditions,a series of 2-alkoxypyrimidine compounds were synthesized in good yields without metal catalysts and additional oxidants.It provides a green method for the synthesis of ether compounds by desulfurization coupling.3.The S-N coupling oxidation aromatization reaction of3,4-dihydropyrimidinthione with morpholine under electrochemical conditions was studied to give the series of 2-S-N functionalized pyrimidine products were synthesized with good yields.The structures of these compounds were characterized by ¹H NMR,¹³C NMR,HRMS.