摘要:芳基硼酸的化学转化经历了几十年的发展,目前已经实现C-B键向C-C键、C-O键、C-N键、C-S键、C-X键转化。其中Suzuki偶联反应已经得到了学术界和工业界的广泛应用,正因为此Akira Suzuki教授和Richard F. Heck教授以及Ei-ichi Negishi教授一起分享了2010年的诺贝尔化学奖。与构建C-C时常采用金属钯为催化剂不同,在C-O键、C-N键和C-S键的形成反应中多采用金属铜盐作为催化剂,且反应条件温和,这较传统的 Ullmann偶联反应已有了较大改进,也必将在今后的合成化学中占有重要地位。但是目前芳基硼酸的转化也面临一些局限性,比如在C-C键的形成反应中多数关注的是C-Csp2,对于C-Csp3的形成过程研究的较少。鉴于铜催化剂的廉价易得和丰富的反应化学,我们期望能够通过本论文的研究实现芳基硼酸的高效烷基化反应,进一步拓展芳基硼酸的反应化学。我们以α-溴代乙腈为烷基化试剂,在吡啶亚胺作为配体条件下,在阳离子铜催化下,以中等收率得到了芳基硼酸进行氰甲基化的产物,反应还需进一步优化。在论文研究开展的过程中,意外地发现α-溴代乙腈不仅是腈甲基化试剂,还可以作为溴化试剂高效的实现芳基硼酸的溴化反应,我们通过配体调节,当以1,10-菲咯啉作为配体,氯化亚铜作为催化剂时,反应以中等到优秀的收率得到了芳基硼酸溴化产物。62063
毕业论文关键词:芳基硼酸,铜,腈甲基化,溴化
Copper-catalyzed Cyanomethylation and Bromination of Aryl Boronic Acids
Abstract:C-B bond represents one of the most versatile chemical bond in organic synthesis, which could be transformed to C-C, C-O, C-N, and C-S bond under mild reaction conditions. Until now, a variety of transformations have been achieved based on this chemistry. Among them, Suzuki–Miyaura coupling reaction has been widely employed both academically and industrially. In contrary to the construction of C-C bond, in which palladium catalyst is broadly used, building of C-O, C-N, and C-S bonds from the corresponding C-B bond are mostly conducted with copper salts as catalyst. Although this field has achieved great improvement in the last decades, some limitations are still existed in C-B chemistry, for instance, fewer examples focuses on the construction of C-Csp3 from C-B compared to C-Csp2 bonds. Due to the abundance and easy availability of copper catalyst along with its robust chemistry, we expect to develop a copper-catalyzed system to realize efficient transformation of C-B to C-Csp3 bonds in this dissertation. With α-bromoacetonitrile as the alkylation reagent, we obtained the cyanomethylation product with pyridine-imine as the ligand in moderate yield, which need to be further optimized. During the investigation of the cyanomethylation of phenyl boronic acid, we discovered a catalytic system to transfer C-B bond to C-Br bond unexpectedly. With the choice of 1,10-phenanthroline as the ligand and copper chloride as the catalyst, we obtained the bromination products in moderate to excellent yields.
Key words:Aryl boronic acid, Copper, Cyanomethylation, Bromination
1. 前言
1.1 引言.1
1.2 C-B键向C-C键的转1
1.2.1 C-B向C-Csp转化,芳基硼酸的氰基化反应 .1
1.2.2 C-B向C-Csp2转化,Suzuki 交叉偶联反应2
1.2.3 C-B向C-Csp3转化.4
1.3 C-B键向C-X键的转化.5
1.3.1 C-B键向C-O键的转化5
1.3.2 C-B键向C-N键的转化7
1.3.3 C-B键向C-S键的转化8
1.3.4 C-B键向C-X键的转化8
1.4 论文立意.10
2. 实验部分
2.1 仪器和试剂10
2.1.1 本实验所用试剂 11
2.1.2 本实验所用仪器12