Synthesis of Fused Tricyclic Systems from Cycloalkadienones via Diels–Alder Reaction: Sharpless Oxidation of bis Adducts

Abstract

The Diels–Alder reaction between 2,7‐cyclooctadienone and cyclopentadiene goes to completion to produce a bis adduct and mono adduct under InCl₃ conditions. 2,6‐Cycloheptadienone undergoes sequential Diels–Alder reactions in the presence of AlCl₃ with cyclohexadiene and cyclopentadiene to produce the bis adduct. The bis adducts were oxidatively cleaved to produce the [5.8.5] and [5.7.6] tricyclic systems.

Keywords:

• cycloalkadienones
• cyclohexadiene
• cyclopentadiene
• Diels–Alder reaction
• tricyclic systems

Acknowledgement

M. K. thanks CSIR, New Delhi, for a fellowship.