项目名称: 过渡金属催化双键不对称氯化方法学研究
项目编号: No.21302231
项目类型: 青年科学基金项目
立项/批准年度: 2014
项目学科: 数理科学和化学
项目作者: 唐真宇
作者单位: 中南大学
项目金额: 25万元
中文摘要: 发展双键不对称氯化反应已经成为对映体选择性合成具有生物活性含氯天然产物的迫切需要。现有双键不对称卤素化主要集中在不对称卤素内酯化和内醚化等反应上,安装两个不对称氯原子的高选择性氯化反应的例子还很少。在主申请人2009年在天然产物(-)Napyradiomycin A1全合成中开发的第一例高选择性双键不对称氯化反应基础上,本课题受生物氯过氧化酶(chloroperoxidase)催化启发,通过设计均相过渡金属催化氧氯化反应条件,争取通过配体筛选和结构调整来实现对双键的不对称氯化。研究方案包括:1.选用钒、钼、锰等金属高价位氧化物为催化剂前体,筛选氧化剂和含氯试剂组合来实现氧氯化条件;2.在催化循环还不明了的情况下,含过渡金属不对称氯化试剂的开发主要通过二配位/三配位配体金属络和物来实现,配体的选择主要来自钒/钼催化不对称氧化反应;3.通过对催化循环的研究,开发过渡金属催化双键不对称氯化反应。
中文关键词: 双键;不对称;氯化;氟化;脱羧
英文摘要: Development of asymmetric chlorination of olefinic bonds has ranked the utmost research subjects for the enantioselective synthesis of chlorine-containing natural products, which possessed unique anti-cancer, anti-flammable and anti-tumor biological properties. Despite the tremendous advance in the development of enantioselective intramolecular halolactonization and haloetherification, asymmetric olefin dichlorination remains challenging problem, which, by today, only two examples were made. Among them, I have developed the first highly selective asymmetric chlorination of an isolated double bond during the total synthesis of (-)napyradiomycin A1 employing a stoichiometric chiral auxiliary. Inspired by the mechanism studies of halogenating enzyme, especially vanadium chloroperoxidase, we proposed an asymmetric chlorination method, which employed the homogeneous transition metal-catalyzed oxychlorination reaction. In this program, we will also screen, design and modify the chiral ligands to succeed the asymmetric oxychlorination of olefins, which covers several aspects: 1. Development of transition metal catalyzed homogeneous racemic oxychlorination of olefins with the appropriate combination of oxidant and chlorine-containing reagent. We will use vanadium, molybdenum and manganese's high valence oxide as catal
英文关键词: Alkene;Asymmetrical;Chlorination;Fluorination;Decarboxylation