Stereoselective intramolecular Nicholas reaction using epoxides as nucleophiles

FRP Crisóstomo, T Martín, VS Martín

Index: Crisostomo, Fernando R. P.; Martin, Tomas; Martin, Victor S. Organic Letters, 2004 , vol. 6, # 4 p. 565 - 568

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Citation Number: 22

Abstract

The intramolecular nucleophilic attack of the epoxides on the exo-Co2 (CO) 6-propargylic cations provided cyclic ethers in good yields. The use of substrates with stereochemically defined oxiranes provided polysubstituted tetrahydropyrans and oxepanes with a high degree of stereocontrol. The cyclization is sensitive to the nature of the protecting group used at the primary alcohol, the use of tert-butyl carbonates being highly effective in terms ...