Using Natural Chiral Synthesis Of Chiral Phase-transfer Catalyst

Asymmetric synthesis using chiral phase transfer catalyst is a new method that has just been developed in late years. Bisquaternary ammonium salts appeared in 70s, it's unique structure and characteristic have been set a high value. The aim of this thesis is to synthesize four new chiral quaternary ammonium salts and two bisquaternary ammonium salts from the popular material-L-phenylalanine methyl ester hydrochloride and chloramphenicol, and then we used these chiral quarternary ammonium salts in some substitution reactions and addition reactions in order to research their catalytic action and asymmetric induction.Followings are the main work of this thesis:1. It summerized the development and the recently research work on using chiral quaternary ammonium salts as phase transfer catalyst in these years.2. Using L-phenylalanine methyl ester hydrochloride as beginning materially the reaction of dehydrochloride, substitution , and quaterization, we get four new chiral quaternary ammonium salts as phase transfer catalyst: PTC-1, PTC-2, PTC-3 , and PTC-4.3. Using L-phenylalanine methyl ester hydrochloride as beginning material again, by the reaction of dehydrochloride , substitution, and quaterization, we get two new chiral bisquaternary ammonium salts as phase transfer catalyst: PTC-5 and PTC-6.4. All the chiral quaternary amonium salts synthesized and their intermediates were analyzed and characterized by 1H-NMR , IR and Elemental Anal.5. In order to study the catalysis and asymmetric induction of these chiral quaternary ammonium salts ,we used them as phase transfer catalyst in the reaction of addition and the substitution,6. A mode for the asymmetric induction of the chiral phase transfer catalyst was suggested on the basis of the results of the experiment and the relate theory.