New Chiral Br??nsted Acids for Asymmetric Synthesis

用于不对称合成的新型手性布朗斯台德酸

基本信息

批准号：
8636482
负责人：
WILLIAM Dean WULFF
金额：
$ 26.32万
依托单位：
MICHIGAN STATE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-04-01 至 2017-03-31
项目状态：
已结题

项目摘要

DESCRIPTION (provided by applicant): The vaulted biaryl ligands VANOL and VAPOL form a unique polyborate anion with a boroxinate core and is beginning to be recognized as a very unique and versatile platform for asymmetric catalysis. As an ion-pair with a protonated imine, this chiral anion will effect the aziridination of imines with diazo compounds with very high yields, diastereoselectivity and enanatioselectivity. Mechanistic investigations including natural abundance kinetic isotope studies will be undertaken to understand how the boroxinate catalyst is formed and how it functions in a variety of reactions including aziridination reactions. The boroxinate core is anionic and has seven oxygens which all bear some of the negative charge and it is possible that it serves as a template in which more than one substrate can H-bond with the boroxinate core at the same time and this helps to determine the transition state. Computations will be persued in an effort to understand how the substrates interact with the boroxinate core in the transition state of the aziridination and other reactions. In addition to the unique structure of this boroxinate catalyst, its utility is greatly enhanced by the fact that it can be assembled by the substrate from the ligand, a boron source, two equivalents of an alcohol or phenol and three equivalents of water. The diverse array of catalysts that can be generated by this process is thus virtually limitless. Investigations will also be carried out to determine the effectiveness of this boroxinate catalyst in other reactions including the Darzens reaction, [3+2] cycloadditions, aminoallylation of aldehydes, and the Ugi reaction.

描述（由申请人提供）：拱形联芳基配体 VANOL 和 VAPOL 形成具有硼酸核心的独特聚硼酸根阴离子，并开始被认为是用于不对称催化的非常独特且通用的平台。作为与质子化亚胺的离子对，该手性阴离子将以非常高的产率、非对映选择性和对映选择性实现亚胺与重氮化合物的氮丙啶化。将进行包括自然丰度动力学同位素研究在内的机理研究，以了解硼氧酸酯催化剂是如何形成的以及它如何在包括氮丙啶化反应在内的各种反应中发挥作用。硼酸核心是阴离子的，有七个氧原子，它们都带有一些负电荷，它可能作为模板，其中多个底物可以同时与硼酸核心形成氢键，这有助于确定过渡状态。我们将进行计算，以了解在氮丙啶化和其他反应的过渡态中底物如何与硼氧酸酯核心相互作用。除了这种硼氧酸酯催化剂的独特结构之外，它的实用性还大大提高，因为它可以由配体、硼源、两当量的醇或苯酚和三当量的水组成的底物组装而成。因此，该过程可产生的催化剂种类繁多，实际上是无限的。还将进行研究以确定这种硼氧酸酯催化剂在其他反应中的有效性，包括 Darzens 反应、[3+2] 环加成、醛的氨基烯丙基化和 Ugi 反应。

项目成果

期刊论文数量（14）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Catalytic asymmetric synthesis of alkynyl aziridines: both enantiomers of cis-aziridines from one enantiomer of the catalyst.

炔基氮丙啶的催化不对称合成：由催化剂的一种对映体合成顺式氮丙啶的两种对映体。

DOI：
发表时间：
2014-10-20
期刊：
影响因子：
0
作者：
Guan, Yong;López;Lu, Zhenjie;Zhang, Yu;Desai, Aman A;Patwardhan, Aniruddha P;Dai, Yijing;Vetticatt, Mathew J;Wulff, William D
通讯作者：
Wulff, William D

Multicomponent catalytic asymmetric aziridination of aldehydes.

醛的多组分催化不对称氮丙啶化。