Catalysis with C9 Ethers of Cupreine and Cupreidine

The derivative 12 was also applied successfully in the reaction of racemic Baylis-HiUman carbonates with cyanoesters [46], in the preparation of a 3-hydroxy-2-methylene-pentanoate as a starting material for the formal total synthesis of 

4 Cinchona Alkaloids with an Ether or Ester Croup at C9 133 

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