2010 年 68 巻 1 号 p. 19-32
The catalytic synthesis of chiral molecules is of crucial importance in fine chemistry in order to ensure the supply of useful and valuable organic compounds. The importance of this research topic has stimulated chemists worldwide to develop numerous methods of asymmetric catalysis, although the process of developing new catalysts involves tedious effort even when modern methods are used. One way to overcome the time-consuming aspect of the process would be to use the technology of combinatorial chemistry for the discovery and optimization of catalysts. For efficient exploration of novel asymmetric catalysts using the combinatorial approach, a convenient technology of high-throughput screening (HTS) is required for analyzing both catalytic activity (chemical yield) and enantiomeric excess.
With the aim of investigating novel asymmetric catalysts using a library of chiral ligands, we have developed a new high-throughput screening (HTS) by coupling a circular dichroism (CD) detection with a reaction on solid-phase catalysts. Using the “solid-phase catalysis/CD-HTS”, several kinds of new asymmetric catalysts were discovered including an imidazoline-aminophenol-Cu catalyst. A novel catalytic asymmetric Friedel-Crafts/Henry reaction was successfully developed by the imidazoline-aminophenol-Cu catalyst to construct three contiguous acyclic stereocenters.