Diels–Alder reactions of activated furans to cyclopentenone derivatives: a regiodivergent Diels–Alder approach towards polyfunctionalised cis-hydrindanones

Cycloaddition of activated furans 10 to 4-methoxycyclopent-2-enone was unexpectedly found to take place with a regioselectivity opposed to that predicted by FMO theory. The reaction represents a direct route towards polyfunctionalised cis-hydrindanones which are key intermediates for the synthesis of ottelione A, a potent inhibitor of tubulin polymerisation.