N-Heterocyclic Carbenes as Asymmetric Organocatalysts: Reaction Development

合成化学用于在分子尺度上制备结构复杂的材料。分子的复杂性通常与手性有关，手性是一种结构的基本性质，使其不能与镜像重叠。例如，你的右手是手性的，因为它不能叠加到它的镜像（你的左手）上；右手被称为左手的对映体。手性也有重要的影响，因为它意味着右手手套不能戴在左手上。手性的概念延伸到分子水平，分子可以以两种形式存在，不同之处在于它们的原子排列使它们成为镜像；事实上，大多数生物化学过程涉及手性分子的相互作用，这些分子可以以不可重叠的镜像（对映体）形式存在。本提案研究了一类简单的手性有机分子的应用，即n -杂环碳烯，因为它们有选择性地催化形成给定物质的单个对映体的能力。模块化的方法来设计和制备这些活性分子，包含必要的功能和结构，以促进催化将被用来在这一领域取得成功。研究了改变n -杂环碳的结构对其反应性的影响，并研究了这些结果在不对称合成和新的化学转化中的应用。

Synthetic chemistry is used for the preparation of structurally complex materials on a molecular scale. Complexity in molecules is often associated with chirality - the fundamental property of a structure that renders it non-superimposable on its mirror image. For example, your right hand is chiral because it cannot be superimposed upon its mirror image (your left hand); the right hand is called the enantiomer of the left hand. Chirality also has important consequences, as it means that a right-handed glove cannot be worn on the left hand. This concept of chirality extends to the molecular level, where molecules can exist in two forms that differ only in that the arrangement of their atoms make them mirror images; indeed the majority of biochemical processes involve the interaction of chiral molecules that can exist in non-superimposable mirror image (enantiomeric) forms. This proposal investigates the application of a simple class of chiral organic molecule, known as N-heterocyclic carbenes, for their ability to catalyse selectively the formation of a single enantiomer of a given substance. A modular approach to the design and preparation of these reactive molecules that contain the necessary function and structure to promote catalysis will be used to succeed in this area. The effect of changing the structure of the N-heterocyclic carbene upon its reactivity will also be probed, and the application of these results to asymmetric synthesis and new chemical transformations investigated.