Catalytic enantioselective addition of enol silanes to ketomalonate mediated by C2-symmetric bisoxazoline Lewis acid complexes

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Frank Reichel, Xiangming Fang, Sulan Yao, Marina Ricci and Karl Anker Jørgensen


Abstract

A catalytic enantioselective addition reaction of silyl enol ethers to ketomalonate in the presence of C2-symmetric copper(II) bisoxazolines as catalysts is presented; the reaction has been studied for different ligands and substrates under various reaction conditions and proceeds in good yield and with ee’s >90% and a procedure for the preparation of an optically active hydroxy acid is shown.


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