Synthesis And Application Of A New Chiral Proline-like Catalyst In Direct Aldol Reaction

1 . The synthesis of (4S)-phenoxy-(S)-proline and its application in asymmetric Direct Aldol reactions(4S)-Phenoxyl-(S)-proline was synthesized from (4R)-Hydroxy-L-Proline. (4R)-Hydroxy-L-Proline was reacted with ethyl chloroformate/ potassium carbonate in absolute methanol to give 4-hydroxypyrrolidine-l,2-dicarboxylic acid 1-ethyl ester 2-methyl ester which was etherified with phenol/PPh3/DEAD followed by hydrolysis to give the target compound. This compound was applied as a catalyst to asymmetric Direct Aldol reactions. Moderate yields and ee's were abtained.2. The synthesis of 4-(4-methylphenoxy)benzylamine4-(4-Methylphenoxy)benzylamine, an important material for the manufacture of insecticide OMI-88, was synthesized via three different methods: 1, the nickel catalyzed hydrogenation of the corresponding cyanide which was prepared from 4-chlorobenzonitrile by Sandmeyer reaction followed by etherification; 2, By the zinc dust reduction of 4-(4-methylphenoxy)bezaldehyde oxime, which was prepared from 4-bromobenzaldehyde by etherification with p-cresol; 3. 4-(4-methylphenoxy)-bezaldehyde, obtained via the same procedure as in method 2, was reduced to the corresponding to the alcohol followed by treatment with thionyl chloride to give the benzyl chloride. Animation of this chloride with urotropine gave the target compound. The second method is more convenient and more practical than the other two.