The Synthesis Of Chiral Epichlorohydrin

Chiral epichlorohydrin is a very important synton in organic synthesis. It is very common and easy to start with chiral epichlorohydrin for the generation of optically active compounds.Compared with some other methods reported, the hydrolytic kinetic resolution (HKR) catalyzed by salen catalysts was chosen for the production of (S)-epichlorohydrin. Firstly, the (Salen)Co(Ⅲ)(OAc) catalyst was synthesized and the e.e.(enantiomeric excess) of the (S)-epichlorohydrin was determined by GC analysis. Secondly, the optimization of the reaction catalyzed by (Salen)Co(Ⅲ)(OAc) was investigated through the mono-factor's experiment. Under the condition that the temperature was 20℃, the water was 0.55 equivalent, and the concentration of the catalyst was 0.5mol%, the e.e. of the (S)-epichlorohydrin would over 99.5% in 10 hours catalyzed by the fresh or the reused (Salen)Co(Ⅲ)(OAc).Finally, some new kinds of Salen catalysts were synthesized, such as [(Salen)Co(Ⅱ)]₂(SnCl₄), [(Salen)Co( Ⅱ )]₂(SnCl₂) , [(Salen)Co( Ⅱ )]₂(FeCl₃) and [(Salen)Co( Ⅱ )]₂(ZnCl₂). The most practical Salen catalysts were picked out through the comparative research for the production of chiral epichlorohydrin.