【作者】 孙绍光；

【导师】 刘群；

【作者基本信息】 东北师范大学 ， 无机化学， 2007， 博士

【摘要】 碳碳键形成和官能团的转化反应是构建有机分子骨架最重要、最基本的反应。Baylis-Hillman反应(以下简称为BH反应)是近年来引起有机化学家广泛兴趣的重要的碳碳键形成反应之一。BH反应系催化剂作用下活化烯(炔)烃和亲电体的偶联反应。因为该反应具有原子经济性、形成多官能团产物等特点,已成为有效地形成碳碳键的重要方法之一。该反应能在较温和的条件下实现各种亲电体和活化烯烃化合物α-位的偶联反应。作为该反应的重要组成部分,活化烯烃由于其本身的结构特征,具有与一般烯烃不同的独特的性质,是非常重要的有机合成中间体。人们已经对该类化合物进行了相当深入的研究,但是对β-位含有取代基,尤其是含有β,β’-双供电子基团的活化烯烃的性质和应用研究还有少。这类烯烃化合物由于受到供电子基团的影响,具有一些不同于一般活化烯烃化合物的独特性质。因此,深入研究具有供电子基团的活化烯烃的各种性质,扩展它们在有机合成化学中的应用具有十分重要的意义。过去的一百年时间里,α-羰基二硫缩烯酮已经成为了一类重要的有机合成中间体。就其结构而言,α-羰基二硫缩烯酮类化合物可视为一类β?位含有两个供电子烷硫基的活化的烯烃。结合上述BH反应的成键特点以及碳碳键形成反应的重要性,本论文拟以β-位上连有双供电子基团的烯类化合物为研究对象,着重研究了这类化合物和各种醛及睛类的三组分反应、与吡啶甲醛的BH反应及产物的应用和芳香醇类的碳碳偶联反应,具体研究内容简述如下:1.首次实现在四氯化钛催化作用下,双烷硫基活化的烯酮类化合物和各种芳香醛及腈类的三组分反应,得到一系列重要的氮杂BH类型产物。该反应首先经历了活化烯烃和醛的BH反应,然后所得的烯丙基醇进一步和乙腈等发生分子间的Ritter反应。该反应具有条件温和、产率较高、产物分子中含有多种官能团等特点。2.研究环烷硫基活化的极化烯酮和糠醛的BH反应,实验结果发现生成的BH加成物没有直接和活化烯烃,而是得到了异常的碳正离子重排后再和活化烯烃反应的产物;并将该反应应用到含有2-呋喃基的BH加成产物,得到了一类结构比较新颖的2, 5-二取代呋喃类化合物。3.首次实现烷硫基活化的烯烃类化合物和吡啶甲醛的BH反应,该反应实现说明了吡啶和四氯化钛配位后能较好对生成的烯丙醇去活化,而不能继续和极化烯或者腈类反应。当用α-氰基二硫缩烯酮和2-吡啶醛反应时,其加成产物可以经过分子内的热环化反应合成具有生物、药物活性的中氮茚衍生物。进一步实验证明这类中氮茚具有很高的亲核性,能在十分温和的条件下和醛酮发生偶联反应,从而合成了一系列含有中氮茚结构单元的三芳基化合物。4.利用烷硫基活化的活化烯烃化合物中的α-碳具有较强亲核性的特点,实现了一系列α-EWG二硫缩烯酮化合物与醇的偶联反应。实验证明,该偶联反应在路易斯酸和质子酸的作用下均能够获得较为理想的结果。实验结果从分说明了这类活化烯烃的α?位具有较强的亲核性。更多还原

【Abstract】 The carbon-carbon bond formation and the functional group transformations are most fundamental reactions for the construction of a molecular framework and hence represent a forefront of research in organic chemistry. The Baylis-Hillman (BH) reaction, the coupling of activated alkenes with carbon electrophiles under relatively mild conditions, is emerging as one of the most valuable carbon-carbon bond forming reaction in recent years. Since the BH reaction possesses the two most requirements, atom economy and generation of useful functional groups,it qualifies to be the list of efficient synthetic reactions. The BH reaction is the coupling reaction of different electrophiles and theα-position of activated alkenes under mild conditions. This reaction possesses three components: activated alkenes, electrophiles and catalyst which produces fused functional groups molecular. As an essential component of the BH reaction, alkenes especially activated alkenes are a kind of very important building blocks in organic synthesis, and have been applied in various fields. While the alkenes which bearβ-substituent(s), especially with electron-donatingβ,β’-disubstituents could have some special characters due to the effect of electron-donating groups (EDGs) and electron-withdrawing groups (EWGs). In contrast to the extensive studies on the common activated alkenes, the investigations on the electron-donating activated alkenes remained few researches. So, it seems to be very important to deeply study the characters and extend applications of this kind of alkenes with EDGs.α-Οxoketene dithioacetals are a kind of versatile intermediates used in organic synthesis during the past decades. It is a type of activated alkenes, which bear double donating alkylthio groups atβ?position. Our recent work focused on the property and synthetic application of this kind of activated alkene. In connection with the characteristic of BH reaction and the importance of carbon-carbon bond formation, we will investigate the three components reaction of alkylthio groups activated alkenes, different aldehydes and nitriles; the BH reaction of pyridine aldehyde and alkylthio groups activated alkenes including the application of the adducts; the carbon-carbon bond coupling reaction of alcohols and polarized ketene dithioacetals. The following statements are the brief of my work. Mediated with titanium (IV) chloride (TiCl4), a series of Aza-Baylis-Hillman reaction adducts were obtained vir three components reaction of bisalkylthio activated polarized alkene, different arylaldehyde and nitrile. This type of reaction is a sequence of Baylis-Hillman reaction and the active adducts was then conformed a Ritter fashion reaction. This reaction covers the mild reaction condition, high yield and the products bearing fused functional groups, etc.When furfural or thiophene-2-carbaldehyde was taken as electrophile, the similar BH type reaction could not give the Aza-BH reaction products. The active alcohol was first produced, and a more stable carbocation was formed after an abnormal rearrangement by the catalyst, which was captured by the activated alkene.The BH reaction of alkylthio activated activated alkenes and picolinaldehyde was realized. The experimental results illuminate that the pyridine can cooperate with titanium and deactivated the corresponding adducts which could not react with activated alkene or nitriles any more. When the BH adducts is derived from the reaction ofα?CN-β,β?bisethylthioketene acetal and picolinaldehyde, it can be converted into potential biological and medicinal active indolizine derivatives after intramolecular themal cyclization reaction. More important, the obtained ethylthio activated indolizine is a type of highly activated carbon nucleophiles. It can be reacted with aldehydes or ketones under very mild conditions to afford a series of triaryl compounds containing indolizine nucleus.The coupling reaction of a series ofα-EWG ketene dithioacetals and alcohols was carried out base on the strong nucleophilicα-position of the tested ketene dithioacetals. The experimental results prove that the reaction can catalyze by either Lewis acid or protonic acid and show high nucleophilic abilities of theα?position of these polarized alkenes.更多还原