中文题名: | 铜催化的不对称硼氢化及其串联反应研究 |
姓名: | |
保密级别: | 公开 |
论文语种: | 中文 |
学科代码: | 070303 |
学科专业: | |
学生类型: | 硕士 |
学位: | 理学硕士 |
学位类型: | |
学位年度: | 2019 |
校区: | |
学院: | |
研究方向: | 不对称催化硼氢化反应的研究 |
第一导师姓名: | |
第一导师单位: | |
提交日期: | 2019-06-27 |
答辩日期: | 2019-05-28 |
外文题名: | Cu-Catalyzed Asymmetric Hydroboration and Cascade reaction |
中文关键词: | 手性有机硼化物 ; 铜催化 ; 不对称催化硼氢化 ; 不对称催化硼烷化 ; 萘基烯丙基胺化合物 ; 1.2-二氢喹啉化合物 |
中文摘要: |
手性有机硼化合物是一类重要的有机合成中间体,广泛应用于生物化学,材料科学,生命健康,医疗制药等领域;因此,合成有机硼化合物具有十分重要的研究意义和广阔的应用前景。金属铜催化的不对称硼氢化反应因其高效性、操作简单、环境友好等优点,近年来已经发展成为合成手性有机硼化合物的重要方法之一。经过几十年的努力,人们已经发展出了许多种催化体系,并将其应用于直链烯烃、环状烯烃以及杂原子烯烃等多种类型底物的不对称催化硼氢化反应,获得了优异的对映选择性。近年来,不对称催化硼氢化反应发展迅速,已经很好的解决了多种底物类型的不对称催化硼氢化反应,催化体系的类型也层见迭出,尽管如此,链状烯丙基取代底物的不对称硼氢化反应仍鲜有报道。另外不对称硼烷化反应作为不对称催化硼氢化串联反应,逐渐成为另一种高效合成手性硼化物的方法,该反应能够一锅法合成具有多手性中心的手性有机硼化物,受到了人们的广泛关注,已发展成为合成手性有机硼化物的有效途径。
本论文旨在实现萘基烯丙基胺类化合物的不对称硼氢化反应以及1,2-二氢喹啉类底物的高效不对称硼烷化反应,筛选出适用于两类底物的最优反应条件,高效高对映选择性地合成手性有机硼化合物。
本论文主要分为两部分:
第一部分:金属铜催化的萘基烯丙基胺化合物的不对称催化硼氢化反应研究。近年来不对称催化硼氢化反应发展迅速,选择合适的催化体系能够很好地解决很多种类型底物的不对称催化硼氢化。但是,有关链状烯丙基类底物的不对称催化硼氢化研究的报道仍然较少;至今为止,萘基烯丙基胺化合物的不对称硼氢化还没有报道过。我们研究发现,利用CuCl和(S,Rp)-JosiPhos-2配体组成催化剂能够高效、高对映选择性地催化一系列具有不同N-保护基团及不同取代基的萘基烯丙基化合物,对映选择性高达96% ee。另外,手性氨基硼化产物能够通过简单的反应高效地转化为重要的手性氨基醇类化合物。
第二部分:金属铜催化的1,2-二氢喹啉化合物的不对称催化硼烷化反应研究。基于对第一部分工作的反应机理研究,我们尝试对1,2-二氢喹啉化合物进行不对称催化硼烷化反应。以CuI和(S,S)-Ph-BPE的络合物为催化剂,对一系列具有不同N-保护基团和不同取代基的1,2-二氢喹啉化合物进行不对称硼烷化研究,获得了优异的非对映选择性和对映选择性(dr > 99:1; ee值高达99.9%)。该研究不仅为多手性中心硼化物的高效合成提供了一条新途径,也将对不对称催化硼烷化研究起到一定的推动作用。
﹀
|
外文摘要: |
Chiral organoboronates play an important role in many research fields, such as synthetic chemistry, materials science, and chemical biology. Additionally, they are the key intermediates in the synthesis of many pharmaceuticals or agrochemicals. Therefore, synthesis of chiral organoboron compounds attracts considerable attention from chemsists over recent years. Cu-Catalyzed asymmetric hydroboration has been developed as one of the most efficient, operation-simple, environmentally friendly methods to obtain enantiomerically enriched organoboronates.
In the past decades, a number of metal catalysts have been developed and excellent activity and enantioselectivity have also been achieved. However, allylic compounds have been rarely investigated in the asymmetric hydroboration. Especially, asymmetric hydroboration of naphthylallylic carbamates remains unexplored so far. Furthermore, copper-catalyzed asymmetric borylalkylation of alkenes has been regarded as another significant approach to access organoboronates with two chiral centers and has also attracted great research interest of chemists recent years.
This dissertation aims to develop efficient catalysts which can exhibit high efficiency and excellent enantioselectivity in the asymmetric hydroboration of naphthylallylic compounds and the enantioselective boylalkylation of 1,2-dihydroquinolines to provide an efficient method for the synthesis of chiral organoboron compounds.
The thesis is composed of two parts:
In the first part, the asymmetric hydroboration of naphthylallylic compounds is investigated. An enantioselective hydroboration of naphthylallylic carbamates under mild conditions has been first realized by using a copper catalyst with a chiral Josiphos ligand to produce a variety of chiral organoboron compounds achieving excellent enantioselectivities (up to 96% ee), which can be readily converted to the corresponding enantio-rich amino alcohols and other useful molecules.
In the second part, copper-catalyzed asymmetric borylalkylation of 1,2-dihydroquinolines is explored. On the basis of the first part of work, we propose a possible catalytic cycle for the hydroboration. Consequently, using 1,2-dihydroquinolines as substrates, we make an attempt to replace methanol with other electrophiles in asymmetric hydroboration. The results show that the complex of copper and (S,S)-Ph-BPE can successfully catalyze the asymmetric borylalklyation of 1,2-dihydroquinolines providing the corresponding organoboron compounds bearing two chiral centers with excellent diastereoselectivities and enantioselectivities (dr > 99:1 and up to 99.9% ee), This research not only provides an efficient and highly enantioselective approach for synthesis of chiral organoboron compounds but also promotes the development of the copper-catalyzed asymmetric carboboration.
﹀
|
参考文献总数: | 69 |
馆藏号: | 硕070303/19011 |
开放日期: | 2020-07-09 |