【作者】 权正军；

【导师】 王喜存；

【作者基本信息】 西北师范大学 ， 高分子化学与物理， 2007， 博士

【摘要】 1893年,意大利化学家Biginelli,P.首次报道,在浓盐酸催化下,利用芳香醛、乙酰乙酸乙酯和尿素三组分“一锅煮法”合成3,4-二氢嘧啶-2-酮衍生物（DHPMs）,这一合成法称为Biginelli反应或Biginelli缩合。自从20世纪90年代以来,此反应受到了人们的广泛关注。大量的催化剂和促进剂被应用于Biginelli缩合反应,缩合所用的醛、乙酰乙酸乙酯和尿素三种原料的范围有了很大的扩展,得到了大量结构新颖的3,4-二氢嘧啶-2-酮类化合物。此外,DHPMs类化合物广谱的生物活性也是近年来人们研究和关注的热点之一。本论文综述了Biginelli反应的研究进展,发展了合成3,4-二氢嘧啶-2-酮类化合物、N3位功能化3,4-二氢嘧啶-2-酮衍生物、5H-噻唑并[3,2-a]嘧啶和二甲基化3,4-二氢嘧啶-2-硫酮衍生物的新方法。这些方法操作简便、产率高、区域选择性好,多数反应是在环境友好的条件下完成的,符合绿色化学的要求。主要研究内容和结果如下:1.合成了聚乙二醇（PEG）支载的磺酸催化剂（PEG-OSO₃H）,研究了其在Biginelli反应中的应用,共合成了15个DHPMs类化合物。该法与文献方法相比,具有反应时间短、后处理简便及催化剂可循环使用等优点。2.合成了DVB交联聚苯乙烯固载PEG树脂支载的磺酸（PS-PEG-OSO₃H）催化剂,研究了其在Biginelli反应中的应用,合成了15个DHPMs类化合物。反应结束后,只需简单的过滤,就可将产物和催化剂分离,并且催化剂可循环使用多次。3.在KF/Al₂O₃催化下,DHPMs与α,β-不饱和羰基化合物发生Michael加成反应,合成了22种新型的N3位功能化的DHPMs衍生物。该法具有反应条件温和、后处理简单、反应区域选择性高、没有副产物等优点。研究结果表明:DHPMs类化合物可与α,β-不饱和羰基化合物发生Michael加成反应,产物只有N3位功能化的DHPMs,而没有N1位的产物。化合物3-（2-甲氧甲酰基-乙基）-6-甲基-2-硫羰基-4-（4-氯苯基）-1,2,3,4-四氢嘧啶-5-甲酸乙酯的X-单晶衍射确证了加成产物的结构。4.发展了一种以PEG-400为反应介质K₂CO₃为碱的反应体系中,DHPMs与α,β-不饱和羰基化合物反应合成N3位功能化DHPMs的新方法。该法以PEG-400为反应介质,且PEG可循环利用,避免了反应过程中有毒溶剂的使用,从而减少了对环境的污染。在此反应体系中,2-氨基-5-芳氧亚甲基-1,3,4-噻二唑与丙烯酸酯反应,意外的得到环合产物—5H,6H-[1,3,4]噻二唑并[1,2-a]嘧啶-7-酮类衍生物。5.在水介质中完成了3,4-二氢嘧啶-2-硫酮与溴代丙酮的缩合反应,合成了10种新型的噻唑并[3,2-a]嘧啶类化合物。该法反应时间短、产率高,且不使用任何有机溶剂。6.以碳酸二甲酯（DMC）为甲基化试剂,弱碱MgO和四丁基溴化胺（TBAB）为催化剂,微波辐射下,研究了3,4-二氢嘧啶-2-硫酮的甲基化反应,得到8种二甲基化的DHPMs衍生物,其中7种为新化合物。DMC的使用避免了剧毒烷基化试剂—碘甲烷或硫酸二甲酯的使用,微波技术的使用极大的缩短了反应时间。因此,该法具有反应选择性好、产率适中、反应时间短和环境友好等优点。更多还原

【Abstract】 Although the acid-catalyzed one-pot condensation of aldehyde,β-ketoester,and urea to afford 3,4-dihydropyrimidinones（DHPMs）,named as the Biginelli reaction from the name of its inventor,has been known for more than a century,the Biginelli-type 3,4-dihydropyrimidinones（DHPMs）were largely ignored in the early part of the 20th century. In the past decades,the scope of the original cyclocondensation reaction was gradually extended by variation of all three building blocks,allowing access to a large number of structurelly diversified multifunctionalized DHPMs.These nonplanar heterocyclic compounds have received considerable attention from the pharmaceutical industry because of their interesting multifaceted pharmacological profiles.In this thesis,the development of the Biginelli reaction.are reviewed and a seres of new methods for the synthesis of 3,4-dihydropyrimidines,N3-functionalized dihydropyrimidines, 5H-thiazolo[3,2-a]pyrimidines and dimethylated 3,4-dihydropyrimidin-thiones are described. These methods have the advantages of simple operation,high yield and high regioselectivity. More than,many reactions were carried out under environmently friendly conditions.The research results are summarized below:1.An efficient and environmentally friendly protocol for the synthesis of 3,4-dihydropyrimidones via the Biginelli-type condensation reaction using poly（ethylene glycol）bounded sulfonic acid as the catalyst under microwave has been developed.The funetionalized poly（ethylene glycol）acted simultaneously as catalyst and solvent in the condensation reaction.The work up was easily operated and the products were obtained in good to excellent yields and high purities.2.A new polymer supported sulfonic acid was prepared by the coupling reaction of crosslinked polystyrene-supported poly（ethylene glycol）with chlorosulfonic.This reagent was used to efficiently perform Biginelli reactions of aldehydes,β-ketoester compounds and urea or thiourea.This resulted in simple one-pot synthesis of the corresponding 3,4-dihydropyrimidinones.This reagent has advantages of simple operation,regeneration and reuse. 3.A simple and efficient method for the synthesis of N3-functionalized 3,4-dihydropyrimidinones by aza-Michael addition reactions of 3,4-dihydropyrimidinones toα,β-ethylenic compounds catalyzed by KF/Al₂O₃ is described.The advantages of this method are high regioselectivity,high purity,and the use of a cheaper,milder,and efficient catalyst for the hetero-Michael addition reaction.4.Poly（ethylene glycol）（PEG）is found to be an inexpensive,non-toxic,environmentally friendly reaction media for the Michael addition of 3,4-dihydropyrimidinones toα;β-ethylenic compounds to give N3-functionalized dihydropyrimidinones.Under the similar reaction conditions,2-amino-5-aryloxymethyl-1,3,4-thiadiazoles reacted with methyl acrylate to give unexpected products 5H,6H-[1,3,4]thiadiazolo[1,2-a]pyrimidine-7-ones through tandem Michael addition and intramolecular cyclization.5.5H-Thiazolo[3,2-a]pyrimidine can be efficiently prepared by the reaction of dihydropyrimidine-2-thione withα-bromoacetone,in water media.The easy and efficacy of this method provide an attractive route for the synthesis of 5H-thiazolo[3,2-a]pyrimidine derivatives.To the best of our knowledge,there has not been reported on the preparation of 5H-thiazolo[3,2-a]pyrimidine derivatives through reaction of dihydropyrimidine-thione withα-bromoacetone in aqueous media.6.An environmentally benign procedure for preparing dimethylated dihydropyrimidin-thiones has been developed by the reaction of dihydropyrimidin-thiones with dimethyl carbonate,a non-toxic and environmentally friendly reagent.The methylated of dihydropyrimidin-thiones is catalysted by MgO and TBAB under microwave.This protocol avoids the use of strong bases and highly toxic agents such as methyl halides or dimethyl sulfate.Additionally,the possible role of MgO/TBAB in the reaction is also presented.更多还原