發(fā)布時間：2018-01-11 11:23

  本文關鍵詞：路易斯酸催化多取代鏈狀二烯Diels-Alder反應研究　出處：《中國科學技術大學》2017年博士論文　論文類型：學位論文

  更多相關文章： 三氟化硼乙醚 多取代鏈狀二烯 α β-不飽和醛 三(五氟苯基)硼 β-酰基丙烯醛 exo構型 Hetero Diels-Alder

【摘要】：本論文主要研究路易斯酸催化多取代鏈狀雙烯在Diels-Alder反應中的反應性能,主要包括以下三部分內容:1.多取代鏈狀二烯與順/反式構型的α,β-不飽和醛在三氟化硼乙醚催化作用下發(fā)生分子間Diels-Alder反應活性差異的研究。我們在探索合成松胞素(Cytochalasans)路線的過程中發(fā)現(xiàn),開鏈多取代雙烯和α,ββ-不飽和醛的順反異構體的反應活性存在很大的差異。在路易斯酸三氟化硼乙醚催化作用下,具有順式或者反式構型的α,β-不飽和醛與簡單的共軛雙烯類化合物的反應活性相差不大。但是對于反應活性較低的開鏈多取代雙烯,使其與順式構型的α,α,β-三取代的不飽和醛類化合物發(fā)生反應,則會得到高產率、高立體選擇性的endo-構型環(huán)加成產物;而與反式構型的α,α,β-三取代的不飽和醛類化合物完全不反應,利用該反應差異性可以高立體選擇性合成含多取代環(huán)己烯片段的天然產物分子。2.大位阻路易斯酸三(五氟苯基)硼催化多取代鏈狀二烯與α,β-不飽和醛exo選擇性的Diels-Alder反應。在這一研究中,通過對反應條件的探索和優(yōu)化,我們發(fā)現(xiàn)利用大位阻強路易斯酸三(五氟苯基)硼可以催化開鏈多取代共軛雙烯與α,β-不飽和醛發(fā)生分子間的Diels-Alder反應,生成exo構型產物。研究還發(fā)現(xiàn),共軛雙烯含叔丁基二苯基硅基取代基時,產物的立體選擇性最高;另外,α,β-不飽和醛的β-位含缺電子取代基時比含富電子基團時的反應效果好。合成了一系列具有exo構型的環(huán)化產物,部分產物通過單晶衍射和2D-NOSEY核磁解析進行了確認。機理研究中,我們認為催化劑與雙烯中的取代基之間的空間位阻效應大大削弱了形成endo構型過渡態(tài)時的二級軌道重疊效應,促使該反應更容易生成exo構型產物。3.三氟化硼乙醚催化多取代鏈狀二烯與反式構型β-�；┤┑姆肿娱gHetero Diels-Alder 反應。在該工作中,我們發(fā)現(xiàn)路易斯酸三氟化硼乙醚可以催化開鏈多取代共軛雙烯與反式構型的β-�；┤┌l(fā)生分子間Hetero Diels-Alder反應。在底物的篩選過程中,我們發(fā)現(xiàn)如果雙烯化合物中含三異丙基硅基取代基,反應得到較高的產率和立體選擇性。另外,共軛雙烯中C-4位如果含大位阻基團則會降低反應活性,而在C-3位如果含線性結構的烷烴取代基時,則會促進反應進行。而β-�；┤┑摩挛蝗绻セ蛲驶〈鶗r,反應都可以中等或者較高的產率和高選擇性得到雜環(huán)Diels-Alder環(huán)化產物。
[Abstract]:This paper mainly studies the catalysis of Lewis acid substituted diene chain reaction performance in Diels-Alder reaction, the main content includes the following three parts: chain substituted diene with cis / trans 1. alpha, beta unsaturated aldehydes on Diels-Alder molecular reactivity differences occur between three boron trifluoride ether as catalyst. We explore the synthesis of cytochalasin (Cytochalasans) found that the route in the process of open chain multi substituted diene and alpha, beta beta unsaturated aldehyde CIS trans isomer reaction activity there is a big difference. In three Lewis acid boron trifluoride ether catalyzed with cis or trans alpha, beta unsaturated reactive aldehydes with simple conjugated diene compounds have little difference. But for the low reactivity of open chain substituted diene, the CIS configuration of alpha, alpha, beta three substituted unsaturated aldehyde compounds occur The reaction, will be of high yield, high stereoselectivity of endo- type cyclic adducts; and trans alpha, alpha, beta three substituted unsaturated aldehydes without reaction, the reaction difference can be highly stereoselective synthesis of multi substituted cyclohexene fragments of natural product molecules.2. macroligand Lewis acid three (five fluoro phenyl) catalyzed by boron substituted diene chain reaction of Diels-Alder and alpha, beta unsaturated aldehyde selectivity of exo. In this study, by exploring and optimizing the reaction conditions, we found that the use of sterically hindered Lewis acid three (five fluoro phenyl) boron can catalyze the open chain multi substituted conjugated dienes and alpha, beta unsaturated aldehyde Diels-Alder reaction between molecules, generating exo configurations of the products. It is also found that the conjugated diene containing two tert butyl phenyl silicone substituent, the product stereoselectivity is highest; in addition, alpha, beta unsaturated aldehyde The beta - containing electron deficient substituent reaction than the effect of containing electron rich groups. When a series of exo configuration of cyclization product synthesis, part of the product is confirmed by X-ray diffraction and 2D-NOSEY NMR. The mechanism research, we believe that between the catalyst and the substituents take 16-dpa in space resistance effect greatly weakened the formation of Endo configuration transition state two molecular orbital overlap effect, prompting the reaction easier to generate the product of exo configuration.3. three boron trifluoride ether catalyzed by substituted diene chain and trans beta acyl acrolein Hetero Diels-Alder reaction. In this work, we found that three of Lewis acid fluoride boron trifluoride ether can catalyze open chain multi substituted conjugated diene and trans beta acyl acrolein intermolecular Hetero Diels-Alder reaction. In the process of selecting the substrate, we found that if 16-dpa. Three isopropyl substituent containing silicon substrate, high yield and the selectivity of response. In addition, conjugated dienes in C-4 position if the macroligand group will reduce the reaction activity, and in the C-3 if the linear structure of alkane substituent, will promote the reaction. While beta propylene acyl if a beta aldehyde containing ester or ketone carbonyl substituents, the reaction can moderate or high yield and high selectivity are heterocyclic Diels-Alder cyclization product.

【學位授予單位】：中國科學技術大學
【學位級別】：博士
【學位授予年份】：2017
【分類號】：O621.251

【相似文獻】

相關期刊論文 前10條

1 戴立信;，

本文編號：1409340