(1) Chiral unnatural aromatic amino acids are key intermediates for medicine and natural products. A series of new optically active aromatic unnatural oxo-amino acids were prepared by Friedel-Crafts reaction of z-aspartic anhydride hydrochloride with corresponding aromatics in the presence of anhydrous Aluminum chloride. The products 2a-c, 3, and 4 were .N-acetylated to form the JV-acetyl amino acids. The structures of these compounds were characterized by JH NMR.(2) Chiral Salen metal complexes are widely employed in catalytic asymmetric reaction. We have tried to prepare chiral Salen-Ln complexes and use them in the ring-opening reaction of racemic epoxides. It was shown that these complexes can catalyze the reaction, but no enantioselectivity was observed in our reaction conditions.
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