Tetrahedron

The synthesis of 8a-methoxy-2H, 6H-chromen-6-ones and corresponding 2H-chromenes by a unique process utilising phenolic oxidation

A Pelter, A Hussain, G Smith, RS Ward

Index: Pelter, Andrew; Hussain, Amjad; Smith, Gareth; Ward, Robert S. Tetrahedron, 1997 , vol. 53, # 11 p. 3879 - 3916

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Citation Number: 32

Abstract

(Z)-1-Hydroxy-3-(3′-hydroxyphenyl) prop-2-enes undergo phenolic oxidation by phenyliodonium diacetate (PIDA) in methanol to give 8a-methoxy-2H, 6H-dihydrochromen-6- ones. These are reduced by DIBAL-H to 2-substituted-Δ3, 4-chromenes, the overall process being a unique heterocyclic synthesis in which the heteroatom is not initially attached to a benzene ring, but is introduced from a side chain. Parallel oxidations using cis-l-hydroxy-3 ...