Abstract
The naturally occurring monoterpene Japanese Hop Ether has been synthesised in 14 steps in an overall yield of 29%. The key step of the synthesis, an intramolecular Pauson-Khand reaction, has been shown to proceed in good to excellent yield under mild N -oxide promotion conditions and with complete retention of alkene stereochemistry (for both cis - and trans -alkenes) in the product cyclopentenone.
Key words
amine N -oxides - cyclopentenones - natural products - Pauson-Khand cyclizations - stereoselectivity
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