ABSTRACT
Optically pure α-substituted propanoic acids and their derivatives represent as an important kind of organic building blocks and key intermediates,which has been widely used in the synthesis of chiral drugs.Some of them have been used directly as nonsteroidal anti-inflammatory drugs (NSAIDs),such as ibuprofen,naproxen,ketoprofen and so on.Dihydroartemisinic acid (DHAA),the same structure as the α-substituted propanic acids,is a key intermediate for the synthesis of artemisinin,the most effective and current used anti-malarial drug.Therefore,the asymmetric synthesis of α-substituted propanoic acids is always a hot topic for chemical scientists.Asymmetric catalytic hydrogenation attracts more and more attentions because of its atom economy and efficiency.This dissertation will disclose the asymmetric synthesis of α-substituted propanoic acids using transition metal-complex as a chiral catalyst.