Tetrahedron

Zirconocene-catalyzed epoxy ester-ortho ester rearrangement: A new method for the protection of polyfunctionalized carboxylic acids and the asymmetric synthesis of …

P Wipf, W Xu, H Kim, H Takahashi

Index: Wipf, Peter; Wenjing, Xu; Hongyong, Kim; Takahashi, Hidenori Tetrahedron, 1997 , vol. 53, # 48 p. 16575 - 16596

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Citation Number: 37

Abstract

In situ prepared Cp2 (Cl) Zr⊛ catalyzes the formation of ortho eśters from epoxy esters. Acid- sensitive α-amino and α-hydroxy acid derivatives are converted in high yield to 2, 7, 8- trioxabicyclo [3.2. 1] octanes (ABO-esters) using this protocol. This strategy is complementary to the OBO-ester technology, and orthogonal methods for the deprotection of ABO-and OBO-esters have been developed. The syntheses of the mushroom components ...