Abstract
In recent years, the development of chiral auxiliaries has been attracting much attention. Although many of these are usually derived from natural chiral compounds, limitations in their structural modification are sometimes an obstacle to achieve an efficient asymmetric process. This problem would be solved by using non-natural chiral compounds due to their two favorable characteristics in contrast to natural products and their derivatives : 1) Both enantiomers are readily available and can be used in asymmetric reactions. 2) The structure can be freely designed.
In the preparation of well-designed, non-natural chiral auxiliaries, the optical resolution of their racemic modifications is thought to be one of the most practical methods. In this context, the development of an efficient method for the optical resolution of a racemic modification is considered to be essential. We have been carrying out a study which was coherent with the design, optical resolution, and application of non-natural chiral auxiliaries. In this review we would like to describe our recent results concerning the development of new non-natural chiral auxiliaries as well as their application to asymmetric syntheses.
